diff --git a/.cursor/rules/dyolink-overview.mdc b/.cursor/rules/dyolink-overview.mdc
index 581523d..08edc17 100644
--- a/.cursor/rules/dyolink-overview.mdc
+++ b/.cursor/rules/dyolink-overview.mdc
@@ -24,6 +24,8 @@ Monorepo: `backend/` (NestJS + Prisma), `frontend/` (Next.js + next-intl), `infr
 
 All user-visible strings: `frontend/messages/en.json`, `fa.json`, `nl.json` — add keys to **all three**.
 
+Dates/times/numbers: `frontend/src/lib/i18n/format.ts` + `useLocale()`. **Form date fields:** `AppDateInput` only (no native `<input type="date">`); wire format `YYYY-MM-DD`. **Filter selects:** `FORM_SELECT_CLASS` from `components/shared/formSelectStyles.ts` (chevron via `globals.css`). **Tables:** `components/ui/shared/Table.tsx` — use `text-start`/`text-end`/`text-center`, never physical `text-left`/`text-right`. Appointments: `ScheduleDayPicker`. Skill: `.cursor/skills/i18n-formatting/SKILL.md`.
+
 ## Treatment / appointment colors
 
 Treatment-type colors and labels: `components/shared/treatmentTypeDisplay.ts` + `catalog-type-colors.ts`. UI badges: `components/ui/treatment/TreatmentTypeBadge.tsx`.
diff --git a/.cursor/rules/frontend-components.mdc b/.cursor/rules/frontend-components.mdc
index 2714891..f338867 100644
--- a/.cursor/rules/frontend-components.mdc
+++ b/.cursor/rules/frontend-components.mdc
@@ -51,3 +51,14 @@ Reference: `app/.../treatment/page.tsx` + `components/ui/treatment/TreatmentWork
 1. Check `components/ui/shared/` for an existing primitive.
 2. Check the feature's `ui/{feature}/` folder for an existing pattern.
 3. Add i18n keys to en, fa, and nl.
+
+## Shared form & table primitives
+
+| Need | Use |
+|------|-----|
+| Date filter / due date field | `AppDateInput` (`ui/shared/`) — not `<input type="date">` |
+| Filter or inline `<select>` | `FORM_SELECT_CLASS` from `components/shared/formSelectStyles.ts` |
+| Tiny select (sort dir, etc.) | `FORM_SELECT_COMPACT_CLASS` |
+| Desktop data table | `Table` (`ui/shared/Table.tsx`) — logical alignment only |
+
+Styles for `.form-select` chevrons live in `styles/globals.css`. Do not duplicate chevron icons on raw selects.
diff --git a/.cursor/skills/i18n-formatting/SKILL.md b/.cursor/skills/i18n-formatting/SKILL.md
new file mode 100644
index 0000000..086c398
--- /dev/null
+++ b/.cursor/skills/i18n-formatting/SKILL.md
@@ -0,0 +1,80 @@
+# i18n formatting (dates, times, numbers)
+
+Use when adding or changing user-visible dates/times/numbers, RTL layout, or locale-specific pickers.
+
+## Display formatting
+
+- Module: `frontend/src/lib/i18n/format.ts`
+- Hook: `frontend/src/lib/hooks/useAppFormatters.ts` (`useLocale()` inside)
+- **Never** use raw `toLocaleDateString` / `toLocaleTimeString` / bare `Intl.DateTimeFormat(undefined, …)` in UI.
+
+| Helper | Use for |
+|--------|---------|
+| `formatAppDate` | Date-only labels |
+| `formatAppTime` | Time-only labels |
+| `formatAppDateTime` | Combined stamp |
+| `formatAppTimeRange` | Appointment ranges |
+| `formatAppTableDate` | Table cells |
+| `formatAppNumber` | Counts, amounts (grouped) |
+| `formatAppInteger` | Calendar year/day — no comma grouping |
+| `formatAppPickerDateLabel` | Calendar trigger button label |
+| `APP_DATE.*` | Shared preset option objects |
+
+## Form controls (dates & selects)
+
+| Piece | Location / use |
+|-------|----------------|
+| **`AppDateInput`** | All form/filter date fields — **every locale**; masked typing + calendar popup; wire value `YYYY-MM-DD` or empty |
+| **`FORM_DATE_INPUT_CLASS`** | Visual shell for date input (same padding/inset as selects; no CSS chevron) |
+| **`FORM_SELECT_CLASS`** | Native `<select>` filters/fields — `ps-3 pe-10`, chevron from `globals.css` |
+| **`FORM_SELECT_COMPACT_CLASS`** | Tiny selects (e.g. sort direction `↓`/`↑`) — symmetric `px-2`, no chevron gutter |
+| **`Dropdown`** | Labeled form select — only where already used; prefer `FORM_SELECT_CLASS` for new filters |
+| **`CompactSelect`** | Year/month/day sub-selects inside calendar panels |
+
+**`AppDateInput` behavior**
+
+- `fa`: Jalali display `YYYY/MM/DD` (Persian digits), parse/mask in `persianCalendar.ts`
+- `en` / `nl`: Gregorian display `YYYY-MM-DD`, parse/mask in `dateInputFormat.ts`
+- Calendar icon at **`end-3`** (matches select chevron inset); text uses **`text-start`** (logical — right in RTL, left in LTR)
+- Popup: **`CalendarDayPartsPanel`** (shared with schedule picker)
+- **Do not** add native `<input type="date">` — one component for all locales
+
+**Select chevron**
+
+- Defined once in `frontend/src/styles/globals.css` on `.form-select:not(.form-select-no-chevron)`
+- RTL: `background-position: left 0.75rem center`; LTR: `right 0.75rem center`
+- `text-align: start` on selects
+
+## Calendar / appointment pickers
+
+| Component | Use for |
+|-----------|---------|
+| `ScheduleDayPicker` | Appointments strip — nav arrows + today toggle + expandable panel |
+| `CalendarDaySelect` | Navigator wrapper (arrows + panel) |
+| `CalendarDayPartsPanel` | Year / month / day row — used by schedule picker and `AppDateInput` |
+
+Persian (`fa`): Jalali calendar + `arabext` digits via Intl (`usesPersianCalendar`). Internal model stays **`Date` at local midnight** (Gregorian) — APIs unchanged.
+
+- Conversion: `frontend/src/lib/i18n/persianCalendar.ts`
+- Gregorian typing: `frontend/src/lib/i18n/dateInputFormat.ts`
+- Gregorian month labels: `schedule.monthJanuary` … message keys
+
+## RTL
+
+- `dir` / `lang` on `<html>` from `app/[locale]/layout.tsx`
+- `isRtlLocale` in `frontend/src/i18n/routing.ts`
+- Use **logical** CSS: `text-start`, `text-end`, `ps-*`, `pe-*`, `ms-*`, `me-*`
+- **`Table`**: default `[&_th]:text-start [&_td]:text-start`; override with `text-center` or `text-end` on cells — **never** `text-left` / `text-right` on headers (causes header/body column drift in RTL)
+- Minimal overrides in `globals.css` — avoid double-mirroring (no extra `row-reverse` on shells that already inherit `direction: rtl`)
+
+## i18n strings
+
+- User-facing copy: `frontend/messages/{en,fa,nl}.json` — all three locales.
+
+## Verify
+
+```bash
+cd frontend && npx tsc --noEmit
+```
+
+Manual: switch to Persian — Cases date filters, Tasks filter row (single line + sort visible), Staff/Orgs table columns aligned; switch to English — date fields match adjacent dropdown alignment.
diff --git a/AGENTS.md b/AGENTS.md
index 7154132..dfe31c4 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -38,6 +38,8 @@ frontend/src/
 
 **Example thin page:** `app/.../treatment/page.tsx` → imports `TreatmentWorkspace` from `components/ui/treatment/`.
 
+**i18n formatting:** Display dates/times/numbers via `lib/i18n/format.ts` + `useLocale()`. Form dates: **`AppDateInput`** (all locales — same component, masked typing + calendar popup). Appointments strip: **`ScheduleDayPicker`**. Filter `<select>`s: **`FORM_SELECT_CLASS`**; data tables: **`Table`** with logical `text-start`/`text-end` (not `text-left`/`text-right`). Skill: `.cursor/skills/i18n-formatting/SKILL.md`.
+
 **Treatment tab:** Preview and editable form are **separate** until the user clicks **Load into workspace** on a history item. See `.cursor/skills/treatment-workspace/SKILL.md` before changing that flow.
 
 **Treatment lab rules (quick ref):**
@@ -75,6 +77,7 @@ Errors: `AppException` + `ErrorCode` → frontend `getUserFacingError()`. Never
 | `.cursor/skills/lab-notifications/` | Tab badges: LabCaseActivity, tab-counts API, read cursors |
 | `.cursor/skills/frontend-structure/` | Moving components, auditing folder layout |
 | `.cursor/skills/api-errors/` | New backend errors + frontend translations |
+| `.cursor/skills/i18n-formatting/` | Dates, times, numbers, Jalali picker, RTL formatting |
 
 ## Subagents (Task tool)
 
diff --git a/frontend/src/app/[locale]/(dashboard)/layout.tsx b/frontend/src/app/[locale]/(dashboard)/layout.tsx
index d16b2c1..7879d56 100644
--- a/frontend/src/app/[locale]/(dashboard)/layout.tsx
+++ b/frontend/src/app/[locale]/(dashboard)/layout.tsx
@@ -72,7 +72,7 @@ export default function DashboardLayout({ children }: { children: React.ReactNod
 
   return (
     <ToastProvider>
-      <div className="flex h-[100dvh] app-web-bg text-text-primary">
+      <div className="app-dashboard-shell flex h-[100dvh] app-web-bg text-text-primary">
       {sidebarOpen ? (
         <button
           type="button"
diff --git a/frontend/src/app/[locale]/layout.tsx b/frontend/src/app/[locale]/layout.tsx
index adb377f..5fffee5 100644
--- a/frontend/src/app/[locale]/layout.tsx
+++ b/frontend/src/app/[locale]/layout.tsx
@@ -4,11 +4,12 @@ import { getMessages, setRequestLocale } from 'next-intl/server';
 import { hasLocale } from 'next-intl';
 import { notFound } from 'next/navigation';
 import Script from 'next/script';
+import { Noto_Sans_Arabic, Vazirmatn } from 'next/font/google';
 import '@/styles/globals.css';
 import '@/styles/background-web.css';
 import { AuthProvider } from '@/lib/hooks/useAuth';
 import { THEME_STORAGE_KEY } from '@/lib/theme';
-import { routing, localeHtmlLang } from '@/i18n/routing';
+import { routing, isRtlLocale, localeHtmlLang } from '@/i18n/routing';
 import { LocaleSync } from '@/components/i18n/LocaleSync';
 
 export const metadata: Metadata = {
@@ -25,6 +26,18 @@ export function generateStaticParams() {
   return routing.locales.map((locale) => ({ locale }));
 }
 
+const vazirmatn = Vazirmatn({
+  subsets: ['arabic'],
+  variable: '--font-vazirmatn',
+  display: 'swap',
+});
+
+const notoSansArabic = Noto_Sans_Arabic({
+  subsets: ['arabic'],
+  variable: '--font-noto-sans-arabic',
+  display: 'swap',
+});
+
 export default async function LocaleLayout({
   children,
   params,
@@ -42,9 +55,20 @@ export default async function LocaleLayout({
   const messages = await getMessages();
 
   const themeInit = `(function(){try{var k=${JSON.stringify(THEME_STORAGE_KEY)};var t=localStorage.getItem(k);document.documentElement.setAttribute('data-theme',t==='light'||t==='dark'?t:'dark');}catch(e){document.documentElement.setAttribute('data-theme','dark');}})();`;
+  const dir = isRtlLocale(locale) ? 'rtl' : 'ltr';
+  const fontSans = isRtlLocale(locale)
+    ? 'var(--font-vazirmatn), var(--font-noto-sans-arabic), system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif'
+    : 'system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif';
 
   return (
-    <html lang={localeHtmlLang(locale)} dir="ltr" suppressHydrationWarning>
+    <html
+      lang={localeHtmlLang(locale)}
+      dir={dir}
+      data-locale={locale}
+      className={`${vazirmatn.variable} ${notoSansArabic.variable}`}
+      style={{ ['--font-sans' as never]: fontSans }}
+      suppressHydrationWarning
+    >
       <body>
         <Script id="theme-init" strategy="beforeInteractive">
           {themeInit}
diff --git a/frontend/src/components/appointments/appointmentTime.ts b/frontend/src/components/appointments/appointmentTime.ts
index 5010c6f..4ce0872 100644
--- a/frontend/src/components/appointments/appointmentTime.ts
+++ b/frontend/src/components/appointments/appointmentTime.ts
@@ -1,3 +1,5 @@
+import { formatAppMinuteOfDay } from '@/lib/i18n/format';
+
 /** Normalize to local midnight; invalid input falls back to today. */
 export function startOfLocalDay(d: Date): Date {
   if (Number.isNaN(d.getTime())) {
@@ -45,9 +47,8 @@ export function isSameLocalCalendarDay(a: Date, b: Date): boolean {
   );
 }
 
-export function formatHourLabel(hour: number): string {
-  const d = new Date(2000, 0, 1, hour, 0, 0, 0);
-  return d.toLocaleTimeString(undefined, { hour: 'numeric', hour12: true });
+export function formatHourLabel(hour: number, locale: string): string {
+  return formatAppMinuteOfDay(hour * 60, locale);
 }
 
 /** Local midnight + delta calendar days. */
diff --git a/frontend/src/components/lab/caseDetailUtils.ts b/frontend/src/components/lab/caseDetailUtils.ts
index bf477b2..91cd188 100644
--- a/frontend/src/components/lab/caseDetailUtils.ts
+++ b/frontend/src/components/lab/caseDetailUtils.ts
@@ -1,5 +1,6 @@
 import type { LabCaseDetail } from '@/types/cases';
 import type { CaseToothChartProsthesisRow } from '@/components/ui/lab/CaseToothChartPanel';
+import { formatAppDateTime } from '@/lib/i18n/format';
 
 export function formatPatientName(patient: { firstName: string; lastName: string }) {
   return `${patient.firstName} ${patient.lastName}`.trim();
@@ -7,10 +8,7 @@ export function formatPatientName(patient: { firstName: string; lastName: string
 
 export function formatCaseDateTime(value: string | null, locale: string) {
   if (!value) return '—';
-  return new Intl.DateTimeFormat(locale, {
-    dateStyle: 'medium',
-    timeStyle: 'short',
-  }).format(new Date(value));
+  return formatAppDateTime(value, locale, { dateStyle: 'medium', timeStyle: 'short' });
 }
 
 export function buildCaseProsthesisRows(labCase: LabCaseDetail): CaseToothChartProsthesisRow[] {
diff --git a/frontend/src/components/lab/labCaseDueDateDisplay.ts b/frontend/src/components/lab/labCaseDueDateDisplay.ts
index 6eab896..05bf3e5 100644
--- a/frontend/src/components/lab/labCaseDueDateDisplay.ts
+++ b/frontend/src/components/lab/labCaseDueDateDisplay.ts
@@ -1,4 +1,5 @@
 import type { BadgeVariant } from '@/components/ui/shared/Badge';
+import { formatAppDate, APP_DATE } from '@/lib/i18n/format';
 
 export function toDateInputValue(iso: string | null | undefined): string {
   if (!iso) return '';
@@ -18,13 +19,7 @@ export function formatLabCaseDueDate(
   locale: string,
 ): string | null {
   if (!iso) return null;
-  const date = new Date(iso);
-  if (Number.isNaN(date.getTime())) return null;
-  return new Intl.DateTimeFormat(locale, {
-    year: 'numeric',
-    month: 'short',
-    day: 'numeric',
-  }).format(date);
+  return formatAppDate(iso, locale, APP_DATE.short);
 }
 
 /** Whole calendar days from today (UTC) until due date. Negative = overdue. */
diff --git a/frontend/src/components/shared/formSelectStyles.ts b/frontend/src/components/shared/formSelectStyles.ts
index cb78b11..a635485 100644
--- a/frontend/src/components/shared/formSelectStyles.ts
+++ b/frontend/src/components/shared/formSelectStyles.ts
@@ -1,5 +1,12 @@
 export const FORM_SELECT_CLASS =
-  'form-select rounded border border-border bg-background-card text-text-primary px-2 py-1 text-sm disabled:opacity-60 focus:outline-none focus:ring-2 focus:ring-primary/35';
+  'form-select appearance-none rounded border border-border bg-background-card text-text-primary ps-3 pe-10 py-1 text-sm disabled:opacity-60 focus:outline-none focus:ring-2 focus:ring-primary/35';
+
+/** Same shell as select fields but without the CSS chevron (date picker uses a button icon). */
+export const FORM_DATE_INPUT_CLASS = `${FORM_SELECT_CLASS} form-select-no-chevron text-start`;
+
+/** Tiny selects (e.g. sort direction) — symmetric padding, no chevron gutter. */
+export const FORM_SELECT_COMPACT_CLASS =
+  'form-select form-select-no-chevron appearance-none rounded border border-border bg-background-card text-text-primary px-2 py-1 text-sm text-center disabled:opacity-60 focus:outline-none focus:ring-2 focus:ring-primary/35';
 
 /** Lab task status control — larger tap target on small screens. */
 export const LAB_TASK_STATUS_SELECT_CLASS = `${FORM_SELECT_CLASS} h-[44px] w-full py-2 text-base font-medium sm:h-9 sm:py-1 sm:text-sm sm:max-w-none`;
diff --git a/frontend/src/components/staff/workingHours.ts b/frontend/src/components/staff/workingHours.ts
index f4f646c..9e7413f 100644
--- a/frontend/src/components/staff/workingHours.ts
+++ b/frontend/src/components/staff/workingHours.ts
@@ -1,3 +1,5 @@
+import { formatAppMinuteOfDay } from '@/lib/i18n/format';
+
 export const MINUTES_PER_DAY = 24 * 60;
 export const SCHEDULE_SLOT_MINUTES = 15;
 
@@ -50,9 +52,8 @@ export function timeInputToMinutes(value: string): number | null {
   return h * 60 + m;
 }
 
-export function formatMinuteLabel(minute: number): string {
-  const d = new Date(2000, 0, 1, Math.floor(minute / 60), minute % 60, 0, 0);
-  return d.toLocaleTimeString(undefined, { hour: 'numeric', minute: '2-digit', hour12: true });
+export function formatMinuteLabel(minute: number, locale: string): string {
+  return formatAppMinuteOfDay(minute, locale);
 }
 
 export function emptyWorkingHoursEditorDays(): WorkingHoursEditorDay[] {
diff --git a/frontend/src/components/today/chart-day-labels.ts b/frontend/src/components/today/chart-day-labels.ts
index 1a5b173..2186d95 100644
--- a/frontend/src/components/today/chart-day-labels.ts
+++ b/frontend/src/components/today/chart-day-labels.ts
@@ -1,16 +1,14 @@
 'use client';
 
 import { useMemo } from 'react';
+import { useLocale } from 'next-intl';
+import { APP_DATE, createAppDateFormatter } from '@/lib/i18n/format';
 
 export function useTodayDayLabelFormatter() {
+  const locale = useLocale();
   return useMemo(
-    () =>
-      new Intl.DateTimeFormat(undefined, {
-        weekday: 'short',
-        month: 'short',
-        day: 'numeric',
-      }),
-    [],
+    () => createAppDateFormatter(locale, APP_DATE.chartDay),
+    [locale],
   );
 }
 
diff --git a/frontend/src/components/treatment/caseSendLabel.ts b/frontend/src/components/treatment/caseSendLabel.ts
index c2856c9..99af62e 100644
--- a/frontend/src/components/treatment/caseSendLabel.ts
+++ b/frontend/src/components/treatment/caseSendLabel.ts
@@ -1,4 +1,5 @@
 import type { LinkedOrganizationOption, TreatmentCaseSendInfo } from '@/types/treatment';
+import { formatAppDateTime } from '@/lib/i18n/format';
 
 export type CaseSendLabelT = (
   key: 'sentToAt' | 'fallbackOrgName',
@@ -13,16 +14,17 @@ export function formatCaseSentLines(
     orgs?: LinkedOrganizationOption[];
   } | undefined,
   t: CaseSendLabelT,
+  locale: string,
 ): string[] {
   if (sends?.length) {
     return sends.map((s) => {
-      const at = new Date(s.sentAt).toLocaleString();
+      const at = formatAppDateTime(s.sentAt, locale, { dateStyle: 'medium', timeStyle: 'short' });
       return t('sentToAt', { orgName: s.organizationName, datetime: at });
     });
   }
 
   if (fallback?.sentAt && fallback.organizationIds.length > 0) {
-    const at = new Date(fallback.sentAt).toLocaleString();
+    const at = formatAppDateTime(fallback.sentAt, locale, { dateStyle: 'medium', timeStyle: 'short' });
     const nameById = new Map(fallback.orgs?.map((o) => [o.id, o.name]) ?? []);
     return fallback.organizationIds.map((id) => {
       const name = nameById.get(id) ?? t('fallbackOrgName');
@@ -41,7 +43,8 @@ export function formatCaseSentSummary(
     orgs?: LinkedOrganizationOption[];
   } | undefined,
   t: CaseSendLabelT,
+  locale: string,
 ): string | null {
-  const lines = formatCaseSentLines(sends, fallback, t);
+  const lines = formatCaseSentLines(sends, fallback, t, locale);
   return lines.length > 0 ? lines.join(' · ') : null;
 }
diff --git a/frontend/src/components/ui/appointments/AppointmentOverlapPopover.tsx b/frontend/src/components/ui/appointments/AppointmentOverlapPopover.tsx
index 9b6763d..b3eb84e 100644
--- a/frontend/src/components/ui/appointments/AppointmentOverlapPopover.tsx
+++ b/frontend/src/components/ui/appointments/AppointmentOverlapPopover.tsx
@@ -1,7 +1,7 @@
 'use client';
 
 import { useEffect, useRef } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { DialogCloseButton } from '@/components/ui/shared/DialogCloseButton';
 import {
   purposeBannerStyle,
@@ -9,6 +9,7 @@ import {
 } from '@/components/appointments/appointmentPurposeStyles';
 import type { AppointmentRecord } from '@/types/appointment';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
+import { formatAppTimeRange } from '@/lib/i18n/format';
 
 type AppointmentOverlapPopoverProps = {
   appointments: AppointmentRecord[];
@@ -18,11 +19,8 @@ type AppointmentOverlapPopoverProps = {
   onClose: () => void;
 };
 
-function formatTimeRange(apt: AppointmentRecord): string {
-  const start = new Date(apt.startAt);
-  const end = new Date(apt.endAt);
-  const opts: Intl.DateTimeFormatOptions = { hour: 'numeric', minute: '2-digit' };
-  return `${start.toLocaleTimeString(undefined, opts)} – ${end.toLocaleTimeString(undefined, opts)}`;
+function formatTimeRange(apt: AppointmentRecord, locale: string): string {
+  return formatAppTimeRange(apt.startAt, apt.endAt, locale);
 }
 
 export function AppointmentOverlapPopover({
@@ -32,6 +30,7 @@ export function AppointmentOverlapPopover({
   onSelect,
   onClose,
 }: AppointmentOverlapPopoverProps) {
+  const locale = useLocale();
   const t = useTranslations('appointments');
   const panelRef = useRef<HTMLDivElement>(null);
 
@@ -99,7 +98,7 @@ export function AppointmentOverlapPopover({
                 <p className="text-xs font-medium truncate">
                   {apt.patient.firstName} {apt.patient.lastName}
                 </p>
-                <p className="text-[11px] opacity-90 tabular-nums">{formatTimeRange(apt)}</p>
+                <p className="text-[11px] opacity-90 tabular-nums">{formatTimeRange(apt, locale)}</p>
                 <p className="text-[10px] opacity-80 truncate">
                   {purposeLabel(apt.purpose, treatmentCatalog)}
                 </p>
diff --git a/frontend/src/components/ui/appointments/AppointmentScheduleGrid.tsx b/frontend/src/components/ui/appointments/AppointmentScheduleGrid.tsx
index ba3b7cd..bbbae55 100644
--- a/frontend/src/components/ui/appointments/AppointmentScheduleGrid.tsx
+++ b/frontend/src/components/ui/appointments/AppointmentScheduleGrid.tsx
@@ -1,7 +1,7 @@
 'use client';
 
 import { useMemo, useState } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import type { AppointmentColumnProvider, AppointmentRecord } from '@/types/appointment';
 import {
   SCHEDULE_SLOT_MINUTES,
@@ -96,6 +96,7 @@ export function AppointmentScheduleGrid({
   onAppointmentClick,
   onAppointmentOutsideHours,
 }: AppointmentScheduleGridProps) {
+  const locale = useLocale();
   const t = useTranslations('appointments');
   const [overlapPopover, setOverlapPopover] = useState<OverlapPopoverState | null>(null);
 
@@ -218,7 +219,7 @@ export function AppointmentScheduleGrid({
                     className="absolute left-0 right-0 text-[11px] text-text-muted flex items-start justify-end pr-1.5 pt-0.5 border-b border-border/50"
                     style={{ top, height }}
                   >
-                    {formatMinuteLabel(hour * 60)}
+                    {formatMinuteLabel(hour * 60, locale)}
                   </div>
                 );
               })}
@@ -263,7 +264,7 @@ export function AppointmentScheduleGrid({
                                 : slotDisabled
                                   ? t('slotCannotCreate')
                                   : t('slotBookAt', {
-                                      time: formatMinuteLabel(slotStartMinute),
+                                      time: formatMinuteLabel(slotStartMinute, locale),
                                     })
                           }
                           className={`absolute left-0 right-0 border-b border-border/50 transition-colors ${
diff --git a/frontend/src/components/ui/billing/BillingPage.tsx b/frontend/src/components/ui/billing/BillingPage.tsx
index 729da84..685147e 100644
--- a/frontend/src/components/ui/billing/BillingPage.tsx
+++ b/frontend/src/components/ui/billing/BillingPage.tsx
@@ -2,6 +2,7 @@
 'use client';
 
 import { useMemo, useState } from 'react';
+import { useLocale } from 'next-intl';
 import { Pencil } from 'lucide-react';
 import { Button } from '@/components/ui/shared/Button';
 import { Badge } from '@/components/ui/shared/Badge';
@@ -10,6 +11,7 @@ import { Table } from '@/components/ui/shared/Table';
 import { SearchBar } from '@/components/ui/shared/SearchBar';
 import { useAuth } from '@/lib/hooks/useAuth';
 import { hasPermission } from '@/components/shared/permissions';
+import { formatAppNumber } from '@/lib/i18n/format';
 
 type InvoiceStatus = 'paid' | 'unpaid' | 'overdue';
 
@@ -44,9 +46,11 @@ interface StatCardProps {
   count: number;
   amount: number;
   color: StatCardColor;
+  locale: string;
 }
 
 export function BillingPage() {
+  const locale = useLocale();
   const { currentOrganization } = useAuth();
   const [search, setSearch] = useState('');
   const [statusFilter, setStatusFilter] = useState<(typeof statusFilters)[number]>('all');
@@ -89,10 +93,10 @@ export function BillingPage() {
       </div>
 
       <div className="grid grid-cols-2 xl:grid-cols-4 gap-3 sm:gap-4">
-        <StatCard title="Total Invoices" count={stats.total.count} amount={stats.total.amount} color="blue" />
-        <StatCard title="Unpaid Invoices" count={stats.unpaid.count} amount={stats.unpaid.amount} color="yellow" />
-        <StatCard title="Paid Invoices" count={stats.paid.count} amount={stats.paid.amount} color="green" />
-        <StatCard title="Overdue Invoices" count={stats.overdue.count} amount={stats.overdue.amount} color="red" />
+        <StatCard title="Total Invoices" count={stats.total.count} amount={stats.total.amount} color="blue" locale={locale} />
+        <StatCard title="Unpaid Invoices" count={stats.unpaid.count} amount={stats.unpaid.amount} color="yellow" locale={locale} />
+        <StatCard title="Paid Invoices" count={stats.paid.count} amount={stats.paid.amount} color="green" locale={locale} />
+        <StatCard title="Overdue Invoices" count={stats.overdue.count} amount={stats.overdue.amount} color="red" locale={locale} />
       </div>
 
       <SearchBar
@@ -138,28 +142,28 @@ export function BillingPage() {
         <Table
           headers={
             <tr>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Invoice ID
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Patient name
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Date
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Service
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Total amount
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Paid
               </th>
-              <th className="px-6 py-3 text-center text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-center text-xs font-medium text-text-muted uppercase tracking-wider">
                 Status
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 Action
               </th>
             </tr>
@@ -168,18 +172,18 @@ export function BillingPage() {
             <>
               {filteredInvoices.map((invoice) => (
                 <tr key={invoice.id} className="hover:bg-background-secondary/45">
-                  <td className="px-6 py-1.5 text-sm font-medium text-text-primary">{invoice.id}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-primary">{invoice.patient}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-secondary">{invoice.date}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-primary">{invoice.service}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-primary">${invoice.amount}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-primary">${invoice.paid}</td>
-                  <td className="px-6 py-1.5 text-center align-middle">
+                  <td className="text-sm font-medium text-text-primary">{invoice.id}</td>
+                  <td className="text-sm text-text-primary">{invoice.patient}</td>
+                  <td className="text-sm text-text-secondary">{invoice.date}</td>
+                  <td className="text-sm text-text-primary">{invoice.service}</td>
+                  <td className="text-sm text-text-primary">${invoice.amount}</td>
+                  <td className="text-sm text-text-primary">${invoice.paid}</td>
+                  <td className="text-center align-middle">
                     <Badge variant={statusColors[invoice.status]} className="capitalize">
                       {invoice.status}
                     </Badge>
                   </td>
-                  <td className="px-6 py-1.5">
+                  <td>
                     <InvoiceEditButton canEditBilling={canEditBilling} />
                   </td>
                 </tr>
@@ -276,7 +280,7 @@ function InvoicePagination({ className = '' }: { className?: string }) {
   );
 }
 
-function StatCard({ title, count, amount, color }: StatCardProps) {
+function StatCard({ title, count, amount, color, locale }: StatCardProps) {
   const colors: Record<StatCardColor, string> = {
     blue: '!bg-purpose-visit-bg !text-purpose-visit-fg !border-purpose-visit-border',
     yellow: '!bg-badge-warning-bg !text-badge-warning-fg !border-badge-warning-border',
@@ -287,9 +291,9 @@ function StatCard({ title, count, amount, color }: StatCardProps) {
   return (
     <Card className={`min-w-0 ${colors[color]}`}>
       <p className="text-xs sm:text-sm font-medium leading-snug">{title}</p>
-      <p className="text-xl sm:text-2xl font-bold mt-1 tabular-nums">{count}</p>
+      <p className="text-xl sm:text-2xl font-bold mt-1 tabular-nums">{formatAppNumber(count, locale)}</p>
       <p className="text-xs sm:text-sm font-medium mt-1 tabular-nums truncate">
-        ${amount.toLocaleString()}
+        ${formatAppNumber(amount, locale)}
       </p>
     </Card>
   );
diff --git a/frontend/src/components/ui/lab/CaseDetailPanel.tsx b/frontend/src/components/ui/lab/CaseDetailPanel.tsx
index 4aad002..4356838 100644
--- a/frontend/src/components/ui/lab/CaseDetailPanel.tsx
+++ b/frontend/src/components/ui/lab/CaseDetailPanel.tsx
@@ -247,7 +247,7 @@ export function CaseDetailPanel({
                             onAssignTask(task.id, e.target.value ? e.target.value : null)
                           }
                           aria-label={t('assigneeLabel')}
-                          className={`${FORM_SELECT_CLASS} max-w-[9.5rem] rounded-md px-2 py-0.5 text-xs`}
+                          className={`${FORM_SELECT_CLASS} max-w-[9.5rem] rounded-md py-0.5 text-xs`}
                         >
                           <option value="">{t('assigneeUnassigned')}</option>
                           {assignableStaff.map((staff) => (
diff --git a/frontend/src/components/ui/lab/CasesPage.tsx b/frontend/src/components/ui/lab/CasesPage.tsx
index 3fa349f..5d8bddd 100644
--- a/frontend/src/components/ui/lab/CasesPage.tsx
+++ b/frontend/src/components/ui/lab/CasesPage.tsx
@@ -25,6 +25,7 @@ import { Button } from '@/components/ui/shared/Button';
 import { MobileDetailBackButton } from '@/components/ui/shared/MobileDetailBackButton';
 import { FORM_SELECT_CLASS } from '@/components/shared/formSelectStyles';
 import { SearchBar } from '@/components/ui/shared/SearchBar';
+import { AppDateInput } from '@/components/ui/shared/AppDateInput';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
 import type {
   AssignableTaskStaff,
@@ -267,7 +268,7 @@ export function CasesPage() {
     }
   }
 
-  const filterSelectClass = `${FORM_SELECT_CLASS} w-full rounded-md px-3 py-2`;
+  const filterSelectClass = `${FORM_SELECT_CLASS} w-full min-w-0 rounded-md py-1.5 text-xs sm:py-2 sm:text-sm`;
 
   return (
     <div className="space-y-4">
@@ -333,11 +334,10 @@ export function CasesPage() {
 
             <label className="space-y-1">
               <span className="text-xs font-medium text-text-muted">{t('filterSentFrom')}</span>
-              <input
-                type="date"
+              <AppDateInput
                 value={sentFrom}
-                onChange={(e) => {
-                  setSentFrom(e.target.value);
+                onChange={(next) => {
+                  setSentFrom(next);
                   setPage(1);
                 }}
                 className={filterSelectClass}
@@ -346,11 +346,10 @@ export function CasesPage() {
 
             <label className="space-y-1">
               <span className="text-xs font-medium text-text-muted">{t('filterSentTo')}</span>
-              <input
-                type="date"
+              <AppDateInput
                 value={sentTo}
-                onChange={(e) => {
-                  setSentTo(e.target.value);
+                onChange={(next) => {
+                  setSentTo(next);
                   setPage(1);
                 }}
                 className={filterSelectClass}
diff --git a/frontend/src/components/ui/lab/TaskCaseGroupHeader.tsx b/frontend/src/components/ui/lab/TaskCaseGroupHeader.tsx
index 45c481c..7fd1a18 100644
--- a/frontend/src/components/ui/lab/TaskCaseGroupHeader.tsx
+++ b/frontend/src/components/ui/lab/TaskCaseGroupHeader.tsx
@@ -5,6 +5,7 @@ import { Badge } from '@/components/ui/shared/Badge';
 import { LabCaseDueDateBadge } from '@/components/lab/LabCaseDueDateBadge';
 import type { CaseTaskGroup } from '@/components/lab/taskListGrouping';
 import { countCaseTaskProgress } from '@/components/lab/taskListGrouping';
+import { formatAppDate, APP_DATE } from '@/lib/i18n/format';
 
 function formatPatientName(patient: { firstName: string; lastName: string }) {
   return `${patient.firstName} ${patient.lastName}`.trim();
@@ -20,11 +21,7 @@ export function TaskCaseGroupHeader({ caseGroup, locale }: TaskCaseGroupHeaderPr
   const progress = countCaseTaskProgress(caseGroup);
 
   const sentLabel = caseGroup.caseSentAt
-    ? new Intl.DateTimeFormat(locale, {
-        year: 'numeric',
-        month: 'short',
-        day: 'numeric',
-      }).format(new Date(caseGroup.caseSentAt))
+    ? formatAppDate(caseGroup.caseSentAt, locale, APP_DATE.short)
     : null;
 
   return (
diff --git a/frontend/src/components/ui/lab/TaskRow.tsx b/frontend/src/components/ui/lab/TaskRow.tsx
index a6d09a7..759d5c8 100644
--- a/frontend/src/components/ui/lab/TaskRow.tsx
+++ b/frontend/src/components/ui/lab/TaskRow.tsx
@@ -12,6 +12,7 @@ import {
   labTaskStatusVariant,
 } from '@/components/lab/labTaskStatusDisplay';
 import { LabCaseDueDateBadge } from '@/components/lab/LabCaseDueDateBadge';
+import { formatAppDate, APP_DATE } from '@/lib/i18n/format';
 import { notifyTabBadgesChanged } from '@/lib/tabBadgeUtils';
 import {
   formatToothList,
@@ -64,11 +65,7 @@ export function TaskRow({
   const canEditStatus = canEditLabTaskStatus(task, currentUserId, canEdit);
   const assignedToOther =
     Boolean(task.assignee) && task.assignee!.id !== currentUserId;
-  const taskDate = new Intl.DateTimeFormat(locale, {
-    year: 'numeric',
-    month: 'short',
-    day: 'numeric',
-  }).format(new Date(task.createdAt));
+  const taskDate = formatAppDate(task.createdAt, locale, APP_DATE.short);
 
   const rowClassName = [
     flatMode ? undefined : 'border-b border-border/40 last:border-b-0',
diff --git a/frontend/src/components/ui/lab/TasksPage.tsx b/frontend/src/components/ui/lab/TasksPage.tsx
index 5cc44e1..17b7c75 100644
--- a/frontend/src/components/ui/lab/TasksPage.tsx
+++ b/frontend/src/components/ui/lab/TasksPage.tsx
@@ -4,7 +4,7 @@ import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { useTranslations } from 'next-intl';
 import { Button } from '@/components/ui/shared/Button';
 import { Checkbox } from '@/components/ui/shared/Checkbox';
-import { FORM_SELECT_CLASS } from '@/components/shared/formSelectStyles';
+import { FORM_SELECT_CLASS, FORM_SELECT_COMPACT_CLASS } from '@/components/shared/formSelectStyles';
 import { SearchBar } from '@/components/ui/shared/SearchBar';
 import { TaskCaseGroupHeader } from '@/components/ui/lab/TaskCaseGroupHeader';
 import { TaskProsthesisGroupHeader } from '@/components/ui/lab/TaskProsthesisGroupHeader';
@@ -286,7 +286,7 @@ export function TasksPage() {
     [canEdit, loadTasks, setError, showError, showSuccess, statusFilter, t, tErrors],
   );
 
-  const filterSelectClass = `${FORM_SELECT_CLASS} w-full min-h-[44px] rounded-md px-2 py-2 text-base sm:min-h-0 sm:py-1.5 sm:text-sm`;
+  const filterSelectClass = `${FORM_SELECT_CLASS} w-full min-w-0 rounded-md py-1.5 text-xs sm:py-2 sm:text-sm`;
 
   const sortHintKey = useMemo(() => {
     switch (sortBy) {
@@ -366,7 +366,8 @@ export function TasksPage() {
           onChange={(v) => applyFilterChange(() => setSearch(v))}
           placeholder={t('searchPlaceholder')}
         />
-        <div className="grid gap-2 sm:grid-cols-2 lg:grid-cols-4">
+        <div className="overflow-x-auto">
+          <div className="grid min-w-[44rem] grid-cols-4 gap-2">
           <label className="space-y-1">
             <span className="text-xs text-text-muted">{t('filterClinic')}</span>
             <select
@@ -411,16 +412,16 @@ export function TasksPage() {
               ))}
             </select>
           </label>
-          <label className="space-y-1">
+          <label className="space-y-1 min-w-0">
             <span className="text-xs text-text-muted">{t('sortBy')}</span>
-            <div className="flex gap-1.5">
+            <div className="grid grid-cols-[minmax(0,1fr)_auto] gap-1">
               <select
                 value={sortBy}
                 onChange={(e) => {
                   setSortBy(e.target.value as TaskSortField);
                   clearFocus();
                 }}
-                className={`${filterSelectClass} min-w-0 flex-1`}
+                className={`${filterSelectClass} min-w-0`}
               >
                 <option value="date">{t('sortDate')}</option>
                 <option value="dueDate">{t('sortDueDate')}</option>
@@ -432,7 +433,7 @@ export function TasksPage() {
               <select
                 value={sortDir}
                 onChange={(e) => setSortDir(e.target.value as 'asc' | 'desc')}
-                className={`${FORM_SELECT_CLASS} w-14 shrink-0 rounded-md px-2 py-1.5 text-sm`}
+                className={`${FORM_SELECT_COMPACT_CLASS} w-11 shrink-0 rounded-md py-1.5 text-sm`}
                 aria-label={t('sortDirection')}
               >
                 <option value="desc">↓</option>
@@ -440,6 +441,7 @@ export function TasksPage() {
               </select>
             </div>
           </label>
+          </div>
         </div>
         <div className="flex flex-wrap items-center gap-x-4 gap-y-2">
           <Checkbox
diff --git a/frontend/src/components/ui/organizations/InvitationHistoryDialog.tsx b/frontend/src/components/ui/organizations/InvitationHistoryDialog.tsx
index b8fd245..d5273e0 100644
--- a/frontend/src/components/ui/organizations/InvitationHistoryDialog.tsx
+++ b/frontend/src/components/ui/organizations/InvitationHistoryDialog.tsx
@@ -1,6 +1,6 @@
 'use client';
 
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { DialogCloseButton } from '@/components/ui/shared/DialogCloseButton';
 import { Card } from '@/components/ui/shared/Card';
 import {
@@ -12,12 +12,7 @@ import { CopyInvitationLinkButton } from '@/components/ui/organizations/CopyInvi
 import type { OrganizationInvitationHistoryItemDto } from '@/lib/api/organization';
 import { Badge } from '@/components/ui/shared/Badge';
 import { organizationConnectionStatusVariant } from '@/components/organizations/connectionStatusVariant';
-
-function formatTableDate(value: string): string {
-  const d = new Date(value);
-  if (Number.isNaN(d.getTime())) return '—';
-  return d.toLocaleDateString();
-}
+import { formatAppTableDate } from '@/lib/i18n/format';
 
 type InvitationHistoryDialogProps = {
   open: boolean;
@@ -38,6 +33,7 @@ export function InvitationHistoryDialog({
   copyingInvitationId,
   onCopy,
 }: InvitationHistoryDialogProps) {
+  const locale = useLocale();
   const t = useTranslations('organizations');
 
   function formatInvitationStatusLabel(
@@ -82,7 +78,7 @@ export function InvitationHistoryDialog({
                       <div className="min-w-0">
                         <p className="font-medium text-text-primary truncate">{inv.organizationName}</p>
                         <p className="text-sm text-text-secondary truncate mt-0.5">{inv.ownerEmail}</p>
-                        <p className="text-xs text-text-muted mt-1">{formatTableDate(inv.createdAt)}</p>
+                        <p className="text-xs text-text-muted mt-1">{formatAppTableDate(inv.createdAt, locale)}</p>
                       </div>
                       <Badge variant={organizationConnectionStatusVariant(inv.status)} fixedWidth={false}>
                         {formatInvitationStatusLabel(inv.status)}
@@ -105,19 +101,19 @@ export function InvitationHistoryDialog({
               <Table
                 headers={
                   <tr>
-                    <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+                    <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                       {t('tableOrganization')}
                     </th>
-                    <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+                    <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                       {t('tableOwnerEmail')}
                     </th>
-                    <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+                    <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                       {t('tableDate')}
                     </th>
-                    <th className="px-6 py-3 text-center text-xs font-medium text-text-muted uppercase tracking-wider">
+                    <th className="text-center text-xs font-medium text-text-muted uppercase tracking-wider">
                       {t('tableStatus')}
                     </th>
-                    <th className="px-6 py-3 text-right text-xs font-medium text-text-muted uppercase tracking-wider">
+                    <th className="text-end text-xs font-medium text-text-muted uppercase tracking-wider">
                       {t('tableInvitationLink')}
                     </th>
                   </tr>
@@ -126,17 +122,17 @@ export function InvitationHistoryDialog({
                   <>
                     {items.map((inv) => (
                       <tr key={inv.id} className="hover:bg-background-secondary/45">
-                        <td className="px-6 py-1.5 text-sm text-text-primary">{inv.organizationName}</td>
-                        <td className="px-6 py-1.5 text-sm text-text-secondary">{inv.ownerEmail}</td>
-                        <td className="px-6 py-1.5 text-sm text-text-secondary">
-                          {formatTableDate(inv.createdAt)}
+                        <td className="text-sm text-text-primary">{inv.organizationName}</td>
+                        <td className="text-sm text-text-secondary">{inv.ownerEmail}</td>
+                        <td className="text-sm text-text-secondary">
+                          {formatAppTableDate(inv.createdAt, locale)}
                         </td>
-                        <td className="px-6 py-1.5 text-center align-middle">
+                        <td className="text-center align-middle">
                           <Badge variant={organizationConnectionStatusVariant(inv.status)} fixedWidth={false}>
                             {formatInvitationStatusLabel(inv.status)}
                           </Badge>
                         </td>
-                        <td className="px-6 py-1.5 text-right align-middle">
+                        <td className="text-end align-middle">
                           <CopyInvitationLinkButton
                             invitation={inv}
                             copied={copiedId === inv.id}
diff --git a/frontend/src/components/ui/organizations/OrganizationsPage.tsx b/frontend/src/components/ui/organizations/OrganizationsPage.tsx
index 81c889d..7a3d3fc 100644
--- a/frontend/src/components/ui/organizations/OrganizationsPage.tsx
+++ b/frontend/src/components/ui/organizations/OrganizationsPage.tsx
@@ -2,7 +2,7 @@
 
 import { useCallback, useEffect, useState } from 'react';
 import { useSearchParams } from 'next/navigation';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { useToast } from '@/lib/hooks/useToast';
 import { Check, Trash2, UserPlus, X } from 'lucide-react';
 import { useAuth } from '@/lib/hooks/useAuth';
@@ -26,6 +26,7 @@ import { SearchBar } from '@/components/ui/shared/SearchBar';
 import { Table } from '@/components/ui/shared/Table';
 import { getUserFacingError } from '@/components/shared/formatApiError';
 import { useRouter } from '@/i18n/navigation';
+import { formatAppTableDate } from '@/lib/i18n/format';
 
 function formatOrganizationStatusLabel(status: string): string {
   if (!status) return status;
@@ -33,15 +34,10 @@ function formatOrganizationStatusLabel(status: string): string {
   return lower.charAt(0).toUpperCase() + lower.slice(1);
 }
 
-function formatTableDate(value: string): string {
-  const d = new Date(value);
-  if (Number.isNaN(d.getTime())) return '\u2014';
-  return d.toLocaleDateString();
-}
-
 type TableMode = 'existing' | 'search';
 
 export function OrganizationsPage() {
+  const locale = useLocale();
   const t = useTranslations('organizations');
   const tErrors = useTranslations('errors');
   const tNav = useTranslations('nav');
@@ -58,6 +54,11 @@ export function OrganizationsPage() {
     [tCommon, tErrors],
   );
 
+  const formatTableDate = useCallback(
+    (value: string) => formatAppTableDate(value, locale),
+    [locale],
+  );
+
   const formatConnectionStatusLabel = useCallback(
     (row: CounterpartItemDto, currentOrganizationId: string): string => {
       if (row.status === 'PENDING') {
@@ -389,19 +390,19 @@ export function OrganizationsPage() {
       <Table
         headers={
             <tr>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 {t('tableOrganization')}
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 {t('tableOwnerEmail')}
               </th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">
                 {t('tableDate')}
               </th>
-              <th className="px-6 py-3 text-center text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-center text-xs font-medium text-text-muted uppercase tracking-wider">
                 {t('tableStatus')}
               </th>
-              <th className="px-6 py-3 text-right text-xs font-medium text-text-muted uppercase tracking-wider">
+              <th className="text-end text-xs font-medium text-text-muted uppercase tracking-wider">
                 {t('tableAction')}
               </th>
             </tr>
@@ -410,14 +411,14 @@ export function OrganizationsPage() {
           <>
             {loading || (mode === 'search' && searching) ? (
               <tr>
-                <td colSpan={5} className="px-6 py-8 text-sm text-text-secondary">
+                <td colSpan={5} className="py-8 text-sm text-text-secondary">
                   {tCommon('loadingEllipsis')}
                 </td>
               </tr>
             ) : mode === 'existing' ? (
               existingRows.length === 0 ? (
                 <tr>
-                  <td colSpan={5} className="px-6 py-8 text-sm text-text-secondary">
+                  <td colSpan={5} className="py-8 text-sm text-text-secondary">
                     {t('emptyConnections')}
                   </td>
                 </tr>
@@ -434,19 +435,19 @@ export function OrganizationsPage() {
 
                   return (
                     <tr key={row.id} className="hover:bg-background-secondary/45">
-                      <td className="px-6 py-1.5 text-sm font-medium text-text-primary">
+                      <td className="text-sm font-medium text-text-primary">
                         {row.organizationName}
                       </td>
-                      <td className="px-6 py-1.5 text-sm text-text-secondary">{row.ownerEmail}</td>
-                      <td className="px-6 py-1.5 text-sm text-text-secondary">
+                      <td className="text-sm text-text-secondary">{row.ownerEmail}</td>
+                      <td className="text-sm text-text-secondary">
                         {formatTableDate(row.createdAt)}
                       </td>
-                      <td className="px-6 py-1.5 text-center align-middle">
+                      <td className="text-center align-middle">
                         <Badge variant={organizationConnectionStatusVariant(row.status)} fixedWidth={false}>
                           {formatConnectionStatusLabel(row, currentOrganization.id)}
                         </Badge>
                       </td>
-                      <td className="px-6 py-1.5 text-right">
+                      <td className="text-end">
                         <div className="inline-flex items-center gap-2">
                           {invitationTarget && (
                             <CopyInvitationLinkButton
@@ -503,13 +504,13 @@ export function OrganizationsPage() {
             ) : searchResults.length > 0 ? (
               searchResults.map((r) => (
                 <tr key={r.id} className="hover:bg-background-secondary/45">
-                  <td className="px-6 py-1.5 text-sm font-medium text-text-primary">{r.name}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-secondary">{r.owner.email}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-secondary">{t('statusToday')}</td>
-                  <td className="px-6 py-1.5 text-center align-middle">
+                  <td className="text-sm font-medium text-text-primary">{r.name}</td>
+                  <td className="text-sm text-text-secondary">{r.owner.email}</td>
+                  <td className="text-sm text-text-secondary">{t('statusToday')}</td>
+                  <td className="text-center align-middle">
                     <Badge variant="default" fixedWidth={false}>{t('statusFound')}</Badge>
                   </td>
-                  <td className="px-6 py-1.5 text-right">
+                  <td className="text-end">
                     <button
                       type="button"
                       className="p-2 rounded-md text-text-secondary hover:bg-background-card/80 hover:text-text-primary disabled:text-text-muted disabled:opacity-50"
@@ -527,7 +528,7 @@ export function OrganizationsPage() {
               ))
             ) : (
               <tr>
-                <td colSpan={5} className="px-6 py-6">
+                <td colSpan={5} className="py-6">
                   <div className="flex flex-col gap-3">
                     <p className="text-sm text-text-secondary">
                       {t('noDirectoryResults')}
diff --git a/frontend/src/components/ui/patient/PatientAppointmentHistory.tsx b/frontend/src/components/ui/patient/PatientAppointmentHistory.tsx
index b1825ee..9eb91a8 100644
--- a/frontend/src/components/ui/patient/PatientAppointmentHistory.tsx
+++ b/frontend/src/components/ui/patient/PatientAppointmentHistory.tsx
@@ -1,9 +1,9 @@
 'use client';
 
 import { useEffect, useState } from 'react';
-import { useTranslations } from 'next-intl';
-import { formatTimeForInput } from '@/components/appointments/appointmentTime';
+import { useLocale, useTranslations } from 'next-intl';
 import { purposeLabel } from '@/components/appointments/appointmentPurposeStyles';
+import { APP_DATE, formatAppDate, formatAppTimeRange } from '@/lib/i18n/format';
 import { getUserFacingError } from '@/components/shared/formatApiError';
 import { TreatmentTypeBadge } from '@/components/ui/treatment/TreatmentTypeBadge';
 import { patientsApi } from '@/lib/api/patients';
@@ -15,20 +15,12 @@ interface PatientAppointmentHistoryProps {
   patientId: string;
 }
 
-function formatAppointmentDate(value: string): string {
-  const date = new Date(value);
-  if (Number.isNaN(date.getTime())) {
-    return value;
-  }
-  return date.toLocaleDateString(undefined, {
-    weekday: 'short',
-    year: 'numeric',
-    month: 'short',
-    day: 'numeric',
-  });
+function formatAppointmentDate(value: string, locale: string): string {
+  return formatAppDate(value, locale, APP_DATE.withWeekday);
 }
 
 export function PatientAppointmentHistory({ patientId }: PatientAppointmentHistoryProps) {
+  const locale = useLocale();
   const t = useTranslations('patients');
   const tErrors = useTranslations('errors');
   const [items, setItems] = useState<PatientAppointmentHistoryItem[]>([]);
@@ -91,12 +83,10 @@ export function PatientAppointmentHistory({ patientId }: PatientAppointmentHisto
               <div className="flex flex-col gap-1 sm:flex-row sm:items-start sm:justify-between">
                 <div className="min-w-0">
                   <p className="text-sm font-medium text-text-primary">
-                    {formatAppointmentDate(item.startAt)}
+                    {formatAppointmentDate(item.startAt, locale)}
                   </p>
                   <p className="text-sm text-text-secondary">
-                    {formatTimeForInput(new Date(item.startAt))}
-                    {' – '}
-                    {formatTimeForInput(new Date(item.endAt))}
+                    {formatAppTimeRange(item.startAt, item.endAt, locale)}
                   </p>
                 </div>
                 <div className="flex flex-col gap-1.5 sm:items-end">
diff --git a/frontend/src/components/ui/shared/AppDateInput.tsx b/frontend/src/components/ui/shared/AppDateInput.tsx
new file mode 100644
index 0000000..ebd4dcc
--- /dev/null
+++ b/frontend/src/components/ui/shared/AppDateInput.tsx
@@ -0,0 +1,175 @@
+'use client';
+
+import { useEffect, useId, useRef, useState } from 'react';
+import { useLocale } from 'next-intl';
+import { CalendarDays } from 'lucide-react';
+import { parseDateInput, startOfLocalDay, toDateInputValue } from '@/components/appointments/appointmentTime';
+import { FORM_DATE_INPUT_CLASS } from '@/components/shared/formSelectStyles';
+import { CalendarDayPartsPanel } from '@/components/ui/shared/CalendarDayPartsPanel';
+import {
+  formatIsoAsGregorianDateInput,
+  maskGregorianDateTyping,
+  parseGregorianDateInputText,
+} from '@/lib/i18n/dateInputFormat';
+import { usesPersianCalendar } from '@/lib/i18n/format';
+import {
+  formatIsoAsPersianDateInput,
+  maskJalaliDateTyping,
+  parsePersianDateInputText,
+} from '@/lib/i18n/persianCalendar';
+
+export type AppDateInputProps = {
+  id?: string;
+  value: string;
+  onChange: (value: string) => void;
+  onBlur?: (value: string) => void;
+  disabled?: boolean;
+  className?: string;
+};
+
+/**
+ * Locale-aware date field — wire value is always `YYYY-MM-DD` or empty.
+ * Visual shell matches native `.form-select` (padding, text alignment, icon inset).
+ */
+export function AppDateInput({
+  id,
+  value,
+  onChange,
+  onBlur,
+  disabled = false,
+  className = '',
+}: AppDateInputProps) {
+  const locale = useLocale();
+  const persian = usesPersianCalendar(locale);
+  const panelId = useId();
+  const rootRef = useRef<HTMLDivElement>(null);
+  const [text, setText] = useState('');
+  const [panelOpen, setPanelOpen] = useState(false);
+
+  useEffect(() => {
+    setText(
+      persian ? formatIsoAsPersianDateInput(value) : formatIsoAsGregorianDateInput(value),
+    );
+  }, [persian, value]);
+
+  useEffect(() => {
+    if (!panelOpen) return;
+
+    function onPointerDown(event: MouseEvent) {
+      if (!rootRef.current?.contains(event.target as Node)) {
+        setPanelOpen(false);
+      }
+    }
+
+    function onKeyDown(event: KeyboardEvent) {
+      if (event.key === 'Escape') {
+        setPanelOpen(false);
+      }
+    }
+
+    document.addEventListener('mousedown', onPointerDown);
+    document.addEventListener('keydown', onKeyDown);
+    return () => {
+      document.removeEventListener('mousedown', onPointerDown);
+      document.removeEventListener('keydown', onKeyDown);
+    };
+  }, [panelOpen]);
+
+  const panelAnchorDate = value ? parseDateInput(value) : startOfLocalDay(new Date());
+  const placeholder = persian ? '۱۴۰۴/۰۴/۲۲' : '2026-07-13';
+  const fieldClass = `${FORM_DATE_INPUT_CLASS} w-full ${className}`.trim();
+
+  function formatDisplay(iso: string): string {
+    return persian ? formatIsoAsPersianDateInput(iso) : formatIsoAsGregorianDateInput(iso);
+  }
+
+  function maskTyping(raw: string): string {
+    return persian ? maskJalaliDateTyping(raw) : maskGregorianDateTyping(raw);
+  }
+
+  function parseTyping(raw: string): string | null {
+    return persian ? parsePersianDateInputText(raw) : parseGregorianDateInputText(raw);
+  }
+
+  function commitText(nextText: string): string {
+    const trimmed = nextText.trim();
+    if (!trimmed) {
+      onChange('');
+      setText('');
+      return '';
+    }
+    const iso = parseTyping(trimmed);
+    if (iso) {
+      onChange(iso);
+      setText(formatDisplay(iso));
+      return iso;
+    }
+    setText(value ? formatDisplay(value) : '');
+    return value;
+  }
+
+  function handlePanelChange(day: Date) {
+    const iso = toDateInputValue(day);
+    onChange(iso);
+    setText(formatDisplay(iso));
+  }
+
+  return (
+    <div ref={rootRef} className="relative w-full">
+      <input
+        id={id}
+        type="text"
+        inputMode="numeric"
+        autoComplete="off"
+        value={text}
+        disabled={disabled}
+        placeholder={placeholder}
+        onChange={(e) => setText(maskTyping(e.target.value))}
+        onBlur={() => {
+          const committed = commitText(text);
+          onBlur?.(committed);
+        }}
+        onKeyDown={(e) => {
+          if (e.key === 'Enter') {
+            const committed = commitText(text);
+            onBlur?.(committed);
+            (e.target as HTMLInputElement).blur();
+          }
+        }}
+        className={fieldClass}
+      />
+      <button
+        type="button"
+        disabled={disabled}
+        aria-expanded={panelOpen}
+        aria-controls={`${panelId}-parts`}
+        aria-label={panelOpen ? undefined : 'Open calendar'}
+        onClick={() => {
+          if (!disabled) setPanelOpen((open) => !open);
+        }}
+        className="pointer-events-auto absolute top-1/2 end-3 flex h-4 w-4 -translate-y-1/2 items-center justify-center text-text-muted hover:text-text-primary focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/35 disabled:opacity-60"
+      >
+        <CalendarDays className="h-4 w-4 icon-flat" aria-hidden />
+      </button>
+
+      {panelOpen && !disabled ? (
+        <div
+          id={`${panelId}-parts`}
+          role="dialog"
+          className="absolute left-0 right-0 top-full z-50 mt-1 rounded-[var(--radius-md)] border border-border bg-background-secondary p-3 shadow-lg"
+        >
+          <CalendarDayPartsPanel
+            panelId={panelId}
+            value={panelAnchorDate}
+            onChange={handlePanelChange}
+            closePanelOnDaySelect
+            onAfterSelect={(day) => {
+              setPanelOpen(false);
+              onBlur?.(toDateInputValue(day));
+            }}
+          />
+        </div>
+      ) : null}
+    </div>
+  );
+}
diff --git a/frontend/src/components/ui/shared/CalendarDayPartsPanel.tsx b/frontend/src/components/ui/shared/CalendarDayPartsPanel.tsx
new file mode 100644
index 0000000..1140946
--- /dev/null
+++ b/frontend/src/components/ui/shared/CalendarDayPartsPanel.tsx
@@ -0,0 +1,166 @@
+'use client';
+
+import { useLocale, useTranslations } from 'next-intl';
+import { formatAppInteger, usesPersianCalendar } from '@/lib/i18n/format';
+import {
+  formatPersianMonthLabel,
+  getLocalPersianParts,
+  jalaliDaysInMonth,
+  persianPartsToLocalDate,
+  persianYearRange,
+} from '@/lib/i18n/persianCalendar';
+import { startOfLocalDay } from '@/components/appointments/appointmentTime';
+import { CompactSelect } from '@/components/ui/shared/CompactSelect';
+
+const MONTH_KEYS = [
+  'monthJanuary',
+  'monthFebruary',
+  'monthMarch',
+  'monthApril',
+  'monthMay',
+  'monthJune',
+  'monthJuly',
+  'monthAugust',
+  'monthSeptember',
+  'monthOctober',
+  'monthNovember',
+  'monthDecember',
+] as const;
+
+function daysInMonth(year: number, month: number): number {
+  return new Date(year, month + 1, 0).getDate();
+}
+
+function buildLocalDay(year: number, month: number, day: number): Date {
+  return new Date(year, month, day, 0, 0, 0, 0);
+}
+
+function yearRange(anchor: Date): number[] {
+  const anchorYear = anchor.getFullYear();
+  const years: number[] = [];
+  for (let y = anchorYear - 10; y <= anchorYear + 2; y += 1) {
+    years.push(y);
+  }
+  return years;
+}
+
+export type CalendarDayPartsPanelProps = {
+  panelId: string;
+  value: Date;
+  onChange: (day: Date) => void;
+  closePanelOnDaySelect?: boolean;
+  onAfterSelect?: (day: Date) => void;
+};
+
+/** Year / month / day dropdown row — shared by schedule picker and date fields. */
+export function CalendarDayPartsPanel({
+  panelId,
+  value,
+  onChange,
+  closePanelOnDaySelect = false,
+  onAfterSelect,
+}: CalendarDayPartsPanelProps) {
+  const locale = useLocale();
+  const t = useTranslations('schedule');
+  const normalizedValue = startOfLocalDay(value);
+  const persian = usesPersianCalendar(locale);
+  const jalaliParts = persian ? getLocalPersianParts(normalizedValue) : null;
+  const gregorianYear = normalizedValue.getFullYear();
+  const gregorianMonth = normalizedValue.getMonth();
+  const gregorianDay = normalizedValue.getDate();
+  const years =
+    persian && jalaliParts ? persianYearRange(jalaliParts.year) : yearRange(normalizedValue);
+  const selectedYear = jalaliParts?.year ?? gregorianYear;
+  const selectedMonth = jalaliParts?.month ?? gregorianMonth;
+  const selectedDay = jalaliParts?.day ?? gregorianDay;
+  const dayCount = persian
+    ? jalaliDaysInMonth(selectedYear, selectedMonth)
+    : daysInMonth(selectedYear, selectedMonth);
+
+  function applyParts(year: number, month: number, day: number, closePanel = false) {
+    const maxDay = persian ? jalaliDaysInMonth(year, month) : daysInMonth(year, month);
+    const clampedDay = Math.min(Math.max(1, day), maxDay);
+    onChange(
+      persian
+        ? persianPartsToLocalDate(year, month, clampedDay)
+        : buildLocalDay(year, month, clampedDay),
+    );
+    if (closePanel) {
+      const nextDay = persian
+        ? persianPartsToLocalDate(year, month, clampedDay)
+        : buildLocalDay(year, month, clampedDay);
+      onAfterSelect?.(nextDay);
+    }
+  }
+
+  function formatPanelYear(year: number): string {
+    return persian ? formatAppInteger(year, locale) : String(year);
+  }
+
+  function formatPanelDay(day: number): string {
+    return persian ? formatAppInteger(day, locale) : String(day);
+  }
+
+  return (
+    <div className="grid grid-cols-3 gap-2">
+      <div>
+        <label htmlFor={`${panelId}-year`} className="mb-1 block text-xs font-medium text-text-muted">
+          {t('year')}
+        </label>
+        <CompactSelect
+          id={`${panelId}-year`}
+          value={selectedYear}
+          onChange={(e) => applyParts(Number(e.target.value), selectedMonth, selectedDay)}
+        >
+          {years.map((year) => (
+            <option key={year} value={year}>
+              {formatPanelYear(year)}
+            </option>
+          ))}
+        </CompactSelect>
+      </div>
+
+      <div>
+        <label htmlFor={`${panelId}-month`} className="mb-1 block text-xs font-medium text-text-muted">
+          {t('month')}
+        </label>
+        <CompactSelect
+          id={`${panelId}-month`}
+          value={selectedMonth}
+          onChange={(e) => applyParts(selectedYear, Number(e.target.value), selectedDay)}
+        >
+          {persian
+            ? Array.from({ length: 12 }, (_, i) => i + 1).map((month) => (
+                <option key={month} value={month}>
+                  {formatPersianMonthLabel(selectedYear, month)}
+                </option>
+              ))
+            : MONTH_KEYS.map((key, index) => (
+                <option key={key} value={index}>
+                  {t(key)}
+                </option>
+              ))}
+        </CompactSelect>
+      </div>
+
+      <div>
+        <label htmlFor={`${panelId}-day`} className="mb-1 block text-xs font-medium text-text-muted">
+          {t('day')}
+        </label>
+        <CompactSelect
+          id={`${panelId}-day`}
+          value={selectedDay}
+          onChange={(e) =>
+            applyParts(selectedYear, selectedMonth, Number(e.target.value), closePanelOnDaySelect)
+          }
+        >
+          {Array.from({ length: dayCount }, (_, i) => i + 1).map((day) => (
+            <option key={day} value={day}>
+              {formatPanelDay(day)}
+            </option>
+          ))}
+        </CompactSelect>
+      </div>
+    </div>
+  );
+}
diff --git a/frontend/src/components/ui/shared/CalendarDaySelect.tsx b/frontend/src/components/ui/shared/CalendarDaySelect.tsx
new file mode 100644
index 0000000..5a14db3
--- /dev/null
+++ b/frontend/src/components/ui/shared/CalendarDaySelect.tsx
@@ -0,0 +1,188 @@
+'use client';
+
+import { useEffect, useId, useRef, useState } from 'react';
+import { useLocale, useTranslations } from 'next-intl';
+import { ChevronDown, ChevronLeft, ChevronRight } from 'lucide-react';
+import { isRtlLocale } from '@/i18n/routing';
+import { formatAppPickerDateLabel } from '@/lib/i18n/format';
+import { CalendarDayPartsPanel } from '@/components/ui/shared/CalendarDayPartsPanel';
+import { addCalendarDays, compareLocalDayStart, startOfLocalDay } from '@/components/appointments/appointmentTime';
+import { Checkbox } from '@/components/ui/shared/Checkbox';
+
+export type CalendarDaySelectProps = {
+  value: Date;
+  onChange: (day: Date) => void;
+  label?: string;
+  emptyLabel?: string;
+  isEmpty?: boolean;
+  showHeader?: boolean;
+  showTodayToggle?: boolean;
+  showNavArrows?: boolean;
+  disabled?: boolean;
+  className?: string;
+  triggerClassName?: string;
+  id?: string;
+  onBlur?: () => void;
+  closePanelOnDaySelect?: boolean;
+};
+
+export function CalendarDaySelect({
+  value,
+  onChange,
+  label,
+  emptyLabel,
+  isEmpty = false,
+  showHeader = false,
+  showTodayToggle = false,
+  showNavArrows = false,
+  disabled = false,
+  className,
+  triggerClassName,
+  id,
+  onBlur,
+  closePanelOnDaySelect = true,
+}: CalendarDaySelectProps) {
+  const locale = useLocale();
+  const rtl = isRtlLocale(locale);
+  const t = useTranslations('schedule');
+  const PrevIcon = rtl ? ChevronRight : ChevronLeft;
+  const NextIcon = rtl ? ChevronLeft : ChevronRight;
+  const panelId = useId();
+  const rootRef = useRef<HTMLDivElement>(null);
+  const [panelOpen, setPanelOpen] = useState(false);
+
+  const normalizedValue = startOfLocalDay(value);
+  const today = startOfLocalDay(new Date());
+  const isTodaySelected = !isEmpty && compareLocalDayStart(normalizedValue, today) === 0;
+  const resolvedLabel = label ?? t('defaultLabel');
+  const labelText = isEmpty
+    ? (emptyLabel ?? t('chooseDate'))
+    : formatAppPickerDateLabel(normalizedValue, locale);
+
+  useEffect(() => {
+    if (!panelOpen) return;
+
+    function onPointerDown(event: MouseEvent) {
+      if (!rootRef.current?.contains(event.target as Node)) {
+        setPanelOpen(false);
+        onBlur?.();
+      }
+    }
+
+    function onKeyDown(event: KeyboardEvent) {
+      if (event.key === 'Escape') {
+        setPanelOpen(false);
+        onBlur?.();
+      }
+    }
+
+    document.addEventListener('mousedown', onPointerDown);
+    document.addEventListener('keydown', onKeyDown);
+    return () => {
+      document.removeEventListener('mousedown', onPointerDown);
+      document.removeEventListener('keydown', onKeyDown);
+    };
+  }, [onBlur, panelOpen]);
+
+  const triggerButton = (
+    <button
+      type="button"
+      id={id}
+      disabled={disabled}
+      onClick={() => {
+        if (disabled) return;
+        setPanelOpen((open) => !open);
+      }}
+      aria-expanded={panelOpen}
+      aria-controls={panelId}
+      aria-haspopup="dialog"
+      className={
+        triggerClassName ??
+        `flex flex-1 min-w-0 items-center justify-center gap-3 rounded-[var(--radius-sm)] px-2 py-1.5 text-sm font-medium text-text-primary tabular-nums hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35 disabled:cursor-not-allowed disabled:opacity-60 ${
+          isEmpty ? 'text-text-muted' : ''
+        }`
+      }
+    >
+      <span className="truncate">{labelText}</span>
+      <ChevronDown
+        className={`h-3.5 w-3.5 shrink-0 text-text-muted icon-flat transition-transform ${panelOpen ? 'rotate-180' : ''}`}
+        aria-hidden
+      />
+    </button>
+  );
+
+  return (
+    <div ref={rootRef} className={`relative w-full ${className ?? 'max-w-md'}`}>
+      {showHeader ? (
+        <div className="mb-2 flex items-center justify-between gap-3">
+          <p className="text-sm font-medium text-text-secondary">{resolvedLabel}</p>
+          {showTodayToggle ? (
+            <Checkbox
+              checked={isTodaySelected}
+              onChange={(checked) => {
+                if (checked) {
+                  onChange(today);
+                  setPanelOpen(false);
+                }
+              }}
+              label={t('today')}
+              className="shrink-0"
+            />
+          ) : null}
+        </div>
+      ) : null}
+
+      <div
+        className={`flex items-center gap-1 rounded-[var(--radius-md)] border border-border bg-background-secondary/90 px-1 py-1 shadow-[inset_0_1px_0_rgba(255,255,255,0.02)] ${
+          showNavArrows ? '' : 'py-0.5'
+        }`}
+      >
+        {showNavArrows ? (
+          <button
+            type="button"
+            disabled={disabled}
+            onClick={() => onChange(addCalendarDays(normalizedValue, -1))}
+            className="shrink-0 rounded-[var(--radius-sm)] p-2 text-text-muted hover:text-text-primary hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35 disabled:opacity-60"
+            aria-label={t('previousDay')}
+          >
+            <PrevIcon className="h-4 w-4 icon-flat" />
+          </button>
+        ) : null}
+
+        {triggerButton}
+
+        {showNavArrows ? (
+          <button
+            type="button"
+            disabled={disabled}
+            onClick={() => onChange(addCalendarDays(normalizedValue, 1))}
+            className="shrink-0 rounded-[var(--radius-sm)] p-2 text-text-muted hover:text-text-primary hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35 disabled:opacity-60"
+            aria-label={t('nextDay')}
+          >
+            <NextIcon className="h-4 w-4 icon-flat" />
+          </button>
+        ) : null}
+      </div>
+
+      {panelOpen && !disabled ? (
+        <div
+          id={panelId}
+          role="dialog"
+          aria-label={t('chooseDate')}
+          className="absolute left-0 right-0 top-full z-50 mt-2 rounded-[var(--radius-md)] border border-border bg-background-secondary p-3 shadow-lg"
+        >
+          <CalendarDayPartsPanel
+            panelId={panelId}
+            value={normalizedValue}
+            onChange={onChange}
+            closePanelOnDaySelect={closePanelOnDaySelect}
+            onAfterSelect={(day) => {
+              setPanelOpen(false);
+              onBlur?.();
+            }}
+          />
+        </div>
+      ) : null}
+    </div>
+  );
+}
diff --git a/frontend/src/components/ui/shared/CompactSelect.tsx b/frontend/src/components/ui/shared/CompactSelect.tsx
new file mode 100644
index 0000000..fb18885
--- /dev/null
+++ b/frontend/src/components/ui/shared/CompactSelect.tsx
@@ -0,0 +1,15 @@
+'use client';
+
+type CompactSelectProps = React.SelectHTMLAttributes<HTMLSelectElement>;
+
+/** Compact styled `<select>` — chevron from global `.form-select` styles. */
+export function CompactSelect({ className = '', children, ...props }: CompactSelectProps) {
+  return (
+    <select
+      className={`form-select w-full appearance-none rounded-[var(--radius-sm)] border border-border bg-background-card/90 text-text-primary text-sm ps-3 pe-10 py-1.5 focus:outline-none focus:ring-2 focus:ring-primary/35 focus:border-border-strong disabled:cursor-not-allowed disabled:opacity-60 ${className}`}
+      {...props}
+    >
+      {children}
+    </select>
+  );
+}
diff --git a/frontend/src/components/ui/shared/Dropdown.tsx b/frontend/src/components/ui/shared/Dropdown.tsx
index 25c3cc6..00f93ea 100644
--- a/frontend/src/components/ui/shared/Dropdown.tsx
+++ b/frontend/src/components/ui/shared/Dropdown.tsx
@@ -1,6 +1,5 @@
 'use client';
 
-import { ChevronDown } from 'lucide-react';
 import React, { forwardRef, useId } from 'react';
 
 interface DropdownProps extends React.SelectHTMLAttributes<HTMLSelectElement> {
@@ -24,32 +23,23 @@ export const Dropdown = forwardRef<HTMLSelectElement, DropdownProps>(
           </label>
         )}
 
-        <div className="relative">
-          <select
-            ref={ref}
-            id={selectId}
-            className={`
-              form-select w-full appearance-none rounded-[var(--radius-md)] border
-              ${error ? 'border-red-500' : 'border-border'}
-              bg-background-card text-text-primary
-              pl-4 pr-14 py-2.5 sm:py-2 text-base sm:text-sm
-              focus:outline-none focus:ring-2 focus:ring-primary/35 focus:border-border-strong
-              disabled:opacity-50 disabled:cursor-not-allowed
-              transition-all duration-200 shadow-[inset_0_1px_0_rgba(255,255,255,0.02)]
-              ${className}
-            `}
-            {...props}
-          >
-            {children}
-          </select>
-
-          <div
-            className="pointer-events-none absolute inset-y-0 right-5 flex items-center text-text-muted"
-            aria-hidden
-          >
-            <ChevronDown className="h-4 w-4 icon-flat" />
-          </div>
-        </div>
+        <select
+          ref={ref}
+          id={selectId}
+          className={`
+            form-select w-full appearance-none rounded-[var(--radius-md)] border
+            ${error ? 'border-red-500' : 'border-border'}
+            bg-background-card text-text-primary
+            ps-3 pe-10 py-2.5 sm:py-2 text-base sm:text-sm
+            focus:outline-none focus:ring-2 focus:ring-primary/35 focus:border-border-strong
+            disabled:opacity-50 disabled:cursor-not-allowed
+            transition-all duration-200 shadow-[inset_0_1px_0_rgba(255,255,255,0.02)]
+            ${className}
+          `}
+          {...props}
+        >
+          {children}
+        </select>
 
         {error && (
           <p className="mt-1 text-sm text-red-500">
diff --git a/frontend/src/components/ui/shared/ScheduleDayPicker.tsx b/frontend/src/components/ui/shared/ScheduleDayPicker.tsx
index 09f67ef..a7c78cc 100644
--- a/frontend/src/components/ui/shared/ScheduleDayPicker.tsx
+++ b/frontend/src/components/ui/shared/ScheduleDayPicker.tsx
@@ -1,10 +1,6 @@
 'use client';
 
-import { useEffect, useId, useRef, useState } from 'react';
-import { useTranslations } from 'next-intl';
-import { ChevronDown, ChevronLeft, ChevronRight } from 'lucide-react';
-import { addCalendarDays, compareLocalDayStart, startOfLocalDay } from '@/components/appointments/appointmentTime';
-import { Checkbox } from '@/components/ui/shared/Checkbox';
+import { CalendarDaySelect } from '@/components/ui/shared/CalendarDaySelect';
 
 interface ScheduleDayPickerProps {
   value: Date;
@@ -14,47 +10,6 @@ interface ScheduleDayPickerProps {
   showTodayToggle?: boolean;
 }
 
-const MONTH_KEYS = [
-  'monthJanuary',
-  'monthFebruary',
-  'monthMarch',
-  'monthApril',
-  'monthMay',
-  'monthJune',
-  'monthJuly',
-  'monthAugust',
-  'monthSeptember',
-  'monthOctober',
-  'monthNovember',
-  'monthDecember',
-] as const;
-
-function daysInMonth(year: number, month: number): number {
-  return new Date(year, month + 1, 0).getDate();
-}
-
-function buildLocalDay(year: number, month: number, day: number): Date {
-  return new Date(year, month, day, 0, 0, 0, 0);
-}
-
-function yearRange(anchor: Date): number[] {
-  const anchorYear = anchor.getFullYear();
-  const startYear = anchorYear - 10;
-  const endYear = anchorYear + 2;
-  const years: number[] = [];
-  for (let y = startYear; y <= endYear; y += 1) {
-    years.push(y);
-  }
-  return years;
-}
-
-const selectClassName = `
-  w-full appearance-none rounded-[var(--radius-sm)] border border-border
-  bg-background-card/90 text-text-primary text-sm
-  pl-2 pr-7 py-1.5
-  focus:outline-none focus:ring-2 focus:ring-primary/35 focus:border-border-strong
-`;
-
 /**
  * Calendar day navigator (arrows + year/month/day panel).
  * Does not restrict past dates — parent pages enforce read-only vs editable for schedule grids/forms.
@@ -65,215 +20,14 @@ export function ScheduleDayPicker({
   label,
   showTodayToggle = true,
 }: ScheduleDayPickerProps) {
-  const t = useTranslations('schedule');
-  const panelId = useId();
-  const rootRef = useRef<HTMLDivElement>(null);
-  const [panelOpen, setPanelOpen] = useState(false);
-
-  const normalizedValue = startOfLocalDay(value);
-  const today = startOfLocalDay(new Date());
-  const isTodaySelected = compareLocalDayStart(normalizedValue, today) === 0;
-  const resolvedLabel = label ?? t('defaultLabel');
-
-  const labelText = normalizedValue.toLocaleDateString(undefined, {
-    weekday: 'short',
-    month: 'short',
-    day: 'numeric',
-    year: 'numeric',
-  });
-
-  const years = yearRange(normalizedValue);
-  const selectedYear = normalizedValue.getFullYear();
-  const selectedMonth = normalizedValue.getMonth();
-  const selectedDay = normalizedValue.getDate();
-  const dayCount = daysInMonth(selectedYear, selectedMonth);
-
-  function applyParts(year: number, month: number, day: number, closePanel = false) {
-    const maxDay = daysInMonth(year, month);
-    onChange(buildLocalDay(year, month, Math.min(Math.max(1, day), maxDay)));
-    if (closePanel) {
-      setPanelOpen(false);
-    }
-  }
-
-  useEffect(() => {
-    if (!panelOpen) return;
-
-    function onPointerDown(event: MouseEvent) {
-      if (!rootRef.current?.contains(event.target as Node)) {
-        setPanelOpen(false);
-      }
-    }
-
-    function onKeyDown(event: KeyboardEvent) {
-      if (event.key === 'Escape') {
-        setPanelOpen(false);
-      }
-    }
-
-    document.addEventListener('mousedown', onPointerDown);
-    document.addEventListener('keydown', onKeyDown);
-    return () => {
-      document.removeEventListener('mousedown', onPointerDown);
-      document.removeEventListener('keydown', onKeyDown);
-    };
-  }, [panelOpen]);
-
   return (
-    <div ref={rootRef} className="relative w-full max-w-md">
-      <div className="mb-2 flex items-center justify-between gap-3">
-        <p className="text-sm font-medium text-text-secondary">{resolvedLabel}</p>
-        {showTodayToggle ? (
-          <Checkbox
-            checked={isTodaySelected}
-            onChange={(checked) => {
-              if (checked) {
-                onChange(today);
-                setPanelOpen(false);
-              }
-            }}
-            label={t('today')}
-            className="shrink-0"
-          />
-        ) : null}
-      </div>
-      <div className="flex items-center gap-1 rounded-[var(--radius-md)] border border-border bg-background-secondary/90 px-1 py-1 shadow-[inset_0_1px_0_rgba(255,255,255,0.02)]">
-        <button
-          type="button"
-          onClick={() => onChange(addCalendarDays(normalizedValue, -1))}
-          className="shrink-0 rounded-[var(--radius-sm)] p-2 text-text-muted hover:text-text-primary hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35"
-          aria-label={t('previousDay')}
-        >
-          <ChevronLeft className="h-4 w-4 icon-flat" />
-        </button>
-
-        <button
-          type="button"
-          onClick={() => setPanelOpen((open) => !open)}
-          aria-expanded={panelOpen}
-          aria-controls={panelId}
-          aria-haspopup="dialog"
-          className="flex flex-1 min-w-0 items-center justify-center gap-3 rounded-[var(--radius-sm)] px-2 py-1.5 text-sm font-medium text-text-primary tabular-nums hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35"
-        >
-          <span className="truncate">{labelText}</span>
-          <ChevronDown
-            className={`h-3.5 w-3.5 shrink-0 text-text-muted icon-flat transition-transform ${panelOpen ? 'rotate-180' : ''}`}
-            aria-hidden
-          />
-        </button>
-
-        <button
-          type="button"
-          onClick={() => onChange(addCalendarDays(normalizedValue, 1))}
-          className="shrink-0 rounded-[var(--radius-sm)] p-2 text-text-muted hover:text-text-primary hover:bg-background-card/80 focus:outline-none focus:ring-2 focus:ring-primary/35"
-          aria-label={t('nextDay')}
-        >
-          <ChevronRight className="h-4 w-4 icon-flat" />
-        </button>
-      </div>
-
-      {panelOpen && (
-        <div
-          id={panelId}
-          role="dialog"
-          aria-label={t('chooseDate')}
-          className="absolute left-0 right-0 top-full z-50 mt-2 rounded-[var(--radius-md)] border border-border bg-background-secondary p-3 shadow-lg"
-        >
-          <div className="grid grid-cols-3 gap-2">
-            <div>
-              <label
-                htmlFor={`${panelId}-year`}
-                className="mb-1 block text-xs font-medium text-text-muted"
-              >
-                {t('year')}
-              </label>
-              <div className="relative">
-                <select
-                  id={`${panelId}-year`}
-                  value={selectedYear}
-                  onChange={(e) =>
-                    applyParts(Number(e.target.value), selectedMonth, selectedDay)
-                  }
-                  className={selectClassName}
-                >
-                  {years.map((year) => (
-                    <option key={year} value={year}>
-                      {year}
-                    </option>
-                  ))}
-                </select>
-                <ChevronDown
-                  className="pointer-events-none absolute right-1.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-text-muted icon-flat"
-                  aria-hidden
-                />
-              </div>
-            </div>
-
-            <div>
-              <label
-                htmlFor={`${panelId}-month`}
-                className="mb-1 block text-xs font-medium text-text-muted"
-              >
-                {t('month')}
-              </label>
-              <div className="relative">
-                <select
-                  id={`${panelId}-month`}
-                  value={selectedMonth}
-                  onChange={(e) =>
-                    applyParts(selectedYear, Number(e.target.value), selectedDay)
-                  }
-                  className={selectClassName}
-                >
-                  {MONTH_KEYS.map((key, index) => (
-                    <option key={key} value={index}>
-                      {t(key)}
-                    </option>
-                  ))}
-                </select>
-                <ChevronDown
-                  className="pointer-events-none absolute right-1.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-text-muted icon-flat"
-                  aria-hidden
-                />
-              </div>
-            </div>
-
-            <div>
-              <label
-                htmlFor={`${panelId}-day`}
-                className="mb-1 block text-xs font-medium text-text-muted"
-              >
-                {t('day')}
-              </label>
-              <div className="relative">
-                <select
-                  id={`${panelId}-day`}
-                  value={selectedDay}
-                  onChange={(e) =>
-                    applyParts(
-                      selectedYear,
-                      selectedMonth,
-                      Number(e.target.value),
-                      true,
-                    )
-                  }
-                  className={selectClassName}
-                >
-                  {Array.from({ length: dayCount }, (_, i) => i + 1).map((day) => (
-                    <option key={day} value={day}>
-                      {day}
-                    </option>
-                  ))}
-                </select>
-                <ChevronDown
-                  className="pointer-events-none absolute right-1.5 top-1/2 h-3.5 w-3.5 -translate-y-1/2 text-text-muted icon-flat"
-                  aria-hidden
-                />
-              </div>
-            </div>
-          </div>
-        </div>
-      )}
-    </div>
+    <CalendarDaySelect
+      value={value}
+      onChange={onChange}
+      label={label}
+      showHeader
+      showTodayToggle={showTodayToggle}
+      showNavArrows
+    />
   );
 }
diff --git a/frontend/src/components/ui/shared/Sidebar.tsx b/frontend/src/components/ui/shared/Sidebar.tsx
index 4fc1000..4b2763f 100644
--- a/frontend/src/components/ui/shared/Sidebar.tsx
+++ b/frontend/src/components/ui/shared/Sidebar.tsx
@@ -1,7 +1,7 @@
 'use client';
 
 import { memo, useMemo } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { Link, usePathname } from '@/i18n/navigation';
 import {
   LayoutDashboard,
@@ -31,6 +31,7 @@ import {
   counterpartOrganizationType,
   organizationTypeIcon,
 } from '@/components/shared/organizationTypeIcon';
+import { isRtlLocale } from '@/i18n/routing';
 
 type MenuItem = {
   name: string;
@@ -46,6 +47,8 @@ type SidebarProps = {
 };
 
 function Sidebar({ mobileOpen = false, onClose }: SidebarProps) {
+  const locale = useLocale();
+  const rtl = isRtlLocale(locale);
   const t = useTranslations('nav');
   const tCommon = useTranslations('common');
   const pathname = usePathname();
@@ -98,8 +101,8 @@ function Sidebar({ mobileOpen = false, onClose }: SidebarProps) {
 
   return (
     <aside
-      className={`fixed inset-y-0 left-0 z-50 w-56 min-w-56 shrink-0 bg-background-secondary/95 border-r border-border text-text-primary flex flex-col backdrop-blur-sm transition-transform duration-200 ease-out lg:relative lg:translate-x-0 lg:z-auto ${
-        mobileOpen ? 'translate-x-0' : '-translate-x-full lg:translate-x-0'
+      className={`app-sidebar fixed inset-y-0 left-0 z-50 w-56 min-w-56 shrink-0 bg-background-secondary/95 border-r border-border text-text-primary flex flex-col backdrop-blur-sm transition-transform duration-200 ease-out lg:relative lg:translate-x-0 lg:z-auto ${
+        mobileOpen ? 'translate-x-0' : rtl ? 'translate-x-full lg:translate-x-0' : '-translate-x-full lg:translate-x-0'
       }`}
     >
       <div className="h-[71px] px-4 flex items-center justify-between gap-2">
diff --git a/frontend/src/components/ui/shared/Table.tsx b/frontend/src/components/ui/shared/Table.tsx
index 81f05e7..4653bba 100644
--- a/frontend/src/components/ui/shared/Table.tsx
+++ b/frontend/src/components/ui/shared/Table.tsx
@@ -6,11 +6,12 @@ interface TableProps {
   footer?: ReactNode;
 }
 
+/** Shared data table — logical alignment (`text-start` / `text-end`) for LTR and RTL. */
 export function Table({ headers, body, footer }: TableProps) {
   return (
     <div className="surface-card overflow-hidden">
       <div className="overflow-x-auto">
-        <table className="w-full min-w-[36rem] [&_th]:px-3 sm:[&_th]:px-6 [&_td]:px-3 sm:[&_td]:px-6">
+        <table className="w-full min-w-[36rem] border-collapse [&_th]:px-3 sm:[&_th]:px-6 [&_th]:py-3 [&_th]:text-start [&_td]:px-3 sm:[&_td]:px-6 [&_td]:py-1.5 [&_td]:text-start [&_th.text-center]:text-center [&_td.text-center]:text-center [&_th.text-end]:text-end [&_td.text-end]:text-end">
           <thead className="bg-background-secondary/70 border-b border-border">
             {headers}
           </thead>
diff --git a/frontend/src/components/ui/staff/StaffPage.tsx b/frontend/src/components/ui/staff/StaffPage.tsx
index 0e19b7b..96ec08f 100644
--- a/frontend/src/components/ui/staff/StaffPage.tsx
+++ b/frontend/src/components/ui/staff/StaffPage.tsx
@@ -657,12 +657,12 @@ export function StaffPage() {
         <Table
           headers={
             <tr>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableName')}</th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableEmail')}</th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableRole')}</th>
-              <th className="px-6 py-3 text-center text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableStatus')}</th>
-              <th className="px-6 py-3 text-left text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableAccess')}</th>
-              <th className="px-6 py-3 text-center text-xs font-medium text-text-muted uppercase tracking-wider w-36">
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableName')}</th>
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableEmail')}</th>
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableRole')}</th>
+              <th className="text-center text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableStatus')}</th>
+              <th className="text-xs font-medium text-text-muted uppercase tracking-wider">{t('tableAccess')}</th>
+              <th className="text-center text-xs font-medium text-text-muted uppercase tracking-wider w-36">
                 {t('tableAction')}
               </th>
             </tr>
@@ -671,16 +671,16 @@ export function StaffPage() {
             <>
               {members.map((m) => (
                 <tr key={m.id} className="hover:bg-background-secondary/45">
-                  <td className="px-6 py-1.5 text-sm text-text-primary">{m.name}</td>
-                  <td className="px-6 py-1.5 text-sm text-text-secondary">{m.email}</td>
-                  <td className="px-6 py-1.5 text-sm">
+                  <td className="text-sm text-text-primary">{m.name}</td>
+                  <td className="text-sm text-text-secondary">{m.email}</td>
+                  <td className="text-sm">
                     {m.isOwner ? (
                       <span className="text-primary font-medium">{t('roleOwner')}</span>
                     ) : (
                       <span className="text-text-secondary">{t('roleStaff')}</span>
                     )}
                   </td>
-                  <td className="px-6 py-1.5 align-middle text-center">
+                  <td className="align-middle text-center">
                     {m.isOwner || m.invitationStatus === 'ACTIVE' ? (
                       <Badge variant="success">{t('statusActive')}</Badge>
                     ) : m.invitationStatus === 'PENDING' ? (
@@ -691,7 +691,7 @@ export function StaffPage() {
                       <Badge variant="danger">{t('statusExpired')}</Badge>
                     )}
                   </td>
-                  <td className="px-6 py-1.5 text-sm text-text-secondary max-w-md">
+                  <td className="text-sm text-text-secondary max-w-md">
                     {m.isOwner ? (
                       <span className="text-text-muted">{t('allFeatures')}</span>
                     ) : (
@@ -700,7 +700,7 @@ export function StaffPage() {
                       </span>
                     )}
                   </td>
-                  <td className="px-6 py-1.5 align-middle text-center">
+                  <td className="align-middle text-center">
                     {!m.isOwner && (
                       <div className="flex min-h-[36px] items-center justify-center gap-1 mx-auto w-fit">
                         {canShareStaffInviteLink(m) && (
diff --git a/frontend/src/components/ui/today/TodayPage.tsx b/frontend/src/components/ui/today/TodayPage.tsx
index da0d6c2..0d294dd 100644
--- a/frontend/src/components/ui/today/TodayPage.tsx
+++ b/frontend/src/components/ui/today/TodayPage.tsx
@@ -1,7 +1,7 @@
 'use client';
 
 import { useMemo } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { Link } from '@/i18n/navigation';
 import { useAuth } from '@/lib/hooks/useAuth';
 import { getUserFacingError } from '@/components/shared/formatApiError';
@@ -10,8 +10,10 @@ import { TodayLoadErrorBanner } from '@/components/ui/today/TodayLoadErrorBanner
 import { TodaySectionErrorFallback } from '@/components/ui/today/TodaySectionErrorFallback';
 import { TodayWidgetErrorBoundary } from '@/components/ui/today/TodayWidgetErrorBoundary';
 import { useTodaySummary } from '@/lib/hooks/useTodaySummary';
+import { formatAppTime } from '@/lib/i18n/format';
 
 export function TodayPage() {
+  const locale = useLocale();
   const t = useTranslations('today');
   const tErrors = useTranslations('errors');
   const { currentOrganization } = useAuth();
@@ -32,10 +34,7 @@ export function TodayPage() {
         {data?.generatedAt && !isInitialLoad ? (
           <p className="text-xs text-text-muted">
             {t('lastUpdated', {
-              time: new Intl.DateTimeFormat(undefined, {
-                hour: 'numeric',
-                minute: '2-digit',
-              }).format(new Date(data.generatedAt)),
+              time: formatAppTime(data.generatedAt, locale),
             })}
           </p>
         ) : null}
diff --git a/frontend/src/components/ui/today/TodayUpcomingAppointments.tsx b/frontend/src/components/ui/today/TodayUpcomingAppointments.tsx
index 42c228e..c602b60 100644
--- a/frontend/src/components/ui/today/TodayUpcomingAppointments.tsx
+++ b/frontend/src/components/ui/today/TodayUpcomingAppointments.tsx
@@ -1,11 +1,11 @@
 'use client';
 
 import { useEffect, useState } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { ChevronRight } from 'lucide-react';
 import { Link } from '@/i18n/navigation';
 import { Card } from '@/components/ui/shared/Card';
-import { formatTimeForInput } from '@/components/appointments/appointmentTime';
+import { formatAppTimeRange } from '@/lib/i18n/format';
 import { purposeLabel } from '@/components/appointments/appointmentPurposeStyles';
 import { treatmentAppointmentHref } from '@/components/shared/treatmentSelection';
 import { treatmentTypeColor } from '@/components/shared/treatmentTypeDisplay';
@@ -27,6 +27,7 @@ export function TodayUpcomingAppointments({
   loading = false,
   isInitialLoad = false,
 }: TodayUpcomingAppointmentsProps) {
+  const locale = useLocale();
   const t = useTranslations('today');
   const { currentOrganization } = useAuth();
   const [treatmentCatalog, setTreatmentCatalog] = useState<TreatmentCatalogEntry[]>([]);
@@ -89,9 +90,7 @@ export function TodayUpcomingAppointments({
         <div className="min-h-0 flex-1 overflow-x-hidden overflow-y-auto">
           <ul className="divide-y divide-border/40">
             {appointments.map((appointment) => {
-              const start = new Date(appointment.startAt);
-              const end = new Date(appointment.endAt);
-              const timeLabel = `${formatTimeForInput(start)} – ${formatTimeForInput(end)}`;
+              const timeLabel = formatAppTimeRange(appointment.startAt, appointment.endAt, locale);
               const purposeIndex = treatmentCatalog.findIndex(
                 (entry) => entry.code === appointment.purpose,
               );
diff --git a/frontend/src/components/ui/treatment/AppointmentsStrip.tsx b/frontend/src/components/ui/treatment/AppointmentsStrip.tsx
index 0faec15..47ef79c 100644
--- a/frontend/src/components/ui/treatment/AppointmentsStrip.tsx
+++ b/frontend/src/components/ui/treatment/AppointmentsStrip.tsx
@@ -1,6 +1,6 @@
 'use client';
 
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { CalendarDays } from 'lucide-react';
 import { Card } from '@/components/ui/shared/Card';
 import { ScheduleDayPicker } from '@/components/ui/shared/ScheduleDayPicker';
@@ -11,6 +11,7 @@ import {
 } from '@/components/shared/treatmentTypeDisplay';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
 import type { TreatmentAppointment } from '@/types/treatment';
+import { APP_DATE, formatAppTimeRange } from '@/lib/i18n/format';
 
 interface AppointmentsStripProps {
   stripHidden: boolean;
@@ -35,6 +36,7 @@ export function AppointmentsStrip({
   treatmentCatalog,
   loading = false,
 }: AppointmentsStripProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
 
   if (stripHidden) {
@@ -84,15 +86,7 @@ export function AppointmentsStrip({
         )}
         {appointments.map((a) => {
           const sel = a.id === selectedAppointmentId;
-          const start = new Date(a.startAt);
-          const end = new Date(a.endAt);
-          const timeLabel = `${start.toLocaleTimeString(undefined, {
-            hour: 'numeric',
-            minute: '2-digit',
-          })} – ${end.toLocaleTimeString(undefined, {
-            hour: 'numeric',
-            minute: '2-digit',
-          })}`;
+          const timeLabel = formatAppTimeRange(a.startAt, a.endAt, locale);
           const purposeLabel = treatmentTypeLabelFromCatalog(a.purpose, treatmentCatalog);
           const purposeIndex = treatmentCatalog.findIndex((e) => e.code === a.purpose);
           return (
@@ -104,7 +98,7 @@ export function AppointmentsStrip({
               padding="none"
               style={treatmentTypeBannerStyle(a.purpose, purposeIndex < 0 ? 0 : purposeIndex)}
               className={`
-                text-left rounded-[var(--radius-sm)] px-3 py-2 w-full sm:w-auto sm:min-w-[200px] sm:max-w-[280px] transition-shadow min-h-[52px]
+                text-start rounded-[var(--radius-sm)] px-3 py-2 w-full sm:w-auto sm:min-w-[200px] sm:max-w-[280px] transition-shadow min-h-[52px]
                 focus:outline-none focus-visible:ring-2 focus-visible:ring-primary/45
                 ${sel ? 'ring-2 ring-primary ring-offset-2 ring-offset-background-secondary shadow-[inset_0_1px_0_rgba(255,255,255,0.06)]' : 'hover:brightness-110'}
               `}
diff --git a/frontend/src/components/ui/treatment/CaseSentLabel.tsx b/frontend/src/components/ui/treatment/CaseSentLabel.tsx
index f36df8a..0169b33 100644
--- a/frontend/src/components/ui/treatment/CaseSentLabel.tsx
+++ b/frontend/src/components/ui/treatment/CaseSentLabel.tsx
@@ -1,6 +1,6 @@
 'use client';
 
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { formatCaseSentLines } from '@/components/treatment/caseSendLabel';
 import type { LabCaseSendInfo, LinkedOrganizationOption } from '@/types/treatment';
 
@@ -16,6 +16,7 @@ interface CaseSentLabelProps {
 }
 
 export function CaseSentLabel({ treatmentCase, orgs, className = 'text-xs text-text-muted' }: CaseSentLabelProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
   const organizationIds =
     treatmentCase.sendToOrganizationIds ??
@@ -24,7 +25,7 @@ export function CaseSentLabel({ treatmentCase, orgs, className = 'text-xs text-t
     organizationIds,
     sentAt: treatmentCase.sentAt ?? null,
     orgs,
-  }, t);
+  }, t, locale);
 
   if (lines.length === 0) return null;
 
diff --git a/frontend/src/components/ui/treatment/LabCasesDispatchPanel.tsx b/frontend/src/components/ui/treatment/LabCasesDispatchPanel.tsx
index c6f4a54..b9b2dfa 100644
--- a/frontend/src/components/ui/treatment/LabCasesDispatchPanel.tsx
+++ b/frontend/src/components/ui/treatment/LabCasesDispatchPanel.tsx
@@ -5,6 +5,7 @@ import { useTranslations } from 'next-intl';
 import { Button } from '@/components/ui/shared/Button';
 import { Checkbox } from '@/components/ui/shared/Checkbox';
 import { isDetailReadyForLabDispatch, isLabCaseCompleted } from '@/components/treatment/treatmentDetailRules';
+import { AppDateInput } from '@/components/ui/shared/AppDateInput';
 import { toDateInputValue } from '@/components/lab/labCaseDueDateDisplay';
 import { FORM_SELECT_CLASS } from '@/components/shared/formSelectStyles';
 import { LinkedOrganizationSearchCombobox } from '@/components/ui/treatment/LinkedOrganizationSearchCombobox';
@@ -283,20 +284,17 @@ export function LabCasesDispatchPanel({
             {t('dueDateLabel')}{' '}
             <span className="font-normal text-text-muted">({t('dueDateOptional')})</span>
           </label>
-          <input
+          <AppDateInput
             id={dueDateInputId}
-            type="date"
             value={inputValue}
             disabled={!canEditDueDate}
-            onChange={(e) => {
-              if (!sent) {
-                updateActiveLabCase({ dueDate: e.target.value || null });
-              }
+            onChange={(next) => {
+              updateActiveLabCase({ dueDate: next || null });
             }}
-            onBlur={(e) => {
-              if (sent) void handleSentDueDateBlur(e.target.value);
+            onBlur={(committed) => {
+              if (sent) void handleSentDueDateBlur(committed);
             }}
-            className={`${FORM_SELECT_CLASS} w-full max-w-[11rem] rounded-md px-2 py-1.5 text-sm`}
+            className={`${FORM_SELECT_CLASS} w-full max-w-[11rem] rounded-md py-1.5 text-sm`}
           />
         </div>
         {sent && caseFullyComplete && activeLabCase.dueDate ? (
diff --git a/frontend/src/components/ui/treatment/LabDispatchAttentionPanel.tsx b/frontend/src/components/ui/treatment/LabDispatchAttentionPanel.tsx
index 1cd3731..eeab54a 100644
--- a/frontend/src/components/ui/treatment/LabDispatchAttentionPanel.tsx
+++ b/frontend/src/components/ui/treatment/LabDispatchAttentionPanel.tsx
@@ -1,6 +1,6 @@
 'use client';
 
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { AlertTriangle } from 'lucide-react';
 import { Button } from '@/components/ui/shared/Button';
 import { DetailLabSendBadge } from '@/components/ui/treatment/DetailLabSendBadge';
@@ -9,6 +9,7 @@ import { treatmentTypeLabelFromCatalog } from '@/components/shared/treatmentType
 import type { LabDispatchAttentionItem } from '@/components/treatment/labDispatchAttention';
 import type { LinkedOrganizationOption } from '@/types/treatment';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
+import { APP_DATE, formatAppDate } from '@/lib/i18n/format';
 
 interface LabDispatchAttentionPanelProps {
   items: LabDispatchAttentionItem[];
@@ -27,6 +28,7 @@ export function LabDispatchAttentionPanel({
   onGoToDispatch,
   compact = false,
 }: LabDispatchAttentionPanelProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
 
   if (items.length === 0) {
@@ -54,11 +56,7 @@ export function LabDispatchAttentionPanel({
           const teeth = item.detail.teeth.length
             ? [...item.detail.teeth].sort().join(', ')
             : t('teethNone');
-          const dateLabel = new Date(item.treatmentAt).toLocaleDateString(undefined, {
-            month: 'short',
-            day: 'numeric',
-            year: 'numeric',
-          });
+          const dateLabel = formatAppDate(item.treatmentAt, locale, APP_DATE.short);
 
           return (
             <li
diff --git a/frontend/src/components/ui/treatment/PastTreatmentsPanel.tsx b/frontend/src/components/ui/treatment/PastTreatmentsPanel.tsx
index b1cbad2..5916b3e 100644
--- a/frontend/src/components/ui/treatment/PastTreatmentsPanel.tsx
+++ b/frontend/src/components/ui/treatment/PastTreatmentsPanel.tsx
@@ -1,13 +1,15 @@
 'use client';
 
 import { useMemo, useState } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { Button } from '@/components/ui/shared/Button';
 import { Checkbox } from '@/components/ui/shared/Checkbox';
 import { FORM_SELECT_CLASS } from '@/components/shared/formSelectStyles';
 import { TreatmentHistoryDetailLine } from '@/components/ui/treatment/TreatmentHistoryDetailLine';
 import { DetailLabSendBadge } from '@/components/ui/treatment/DetailLabSendBadge';
 import { filterTreatmentHistoryItems } from '@/components/treatment/treatmentHistoryFilters';
+import { AppDateInput } from '@/components/ui/shared/AppDateInput';
+import { APP_DATE, formatAppDateTime } from '@/lib/i18n/format';
 import type { LinkedOrganizationOption, PastTreatment } from '@/types/treatment';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
 
@@ -25,16 +27,8 @@ interface PastTreatmentsPanelProps {
   compact?: boolean;
 }
 
-function formatHistoryTimestamp(iso: string): string {
-  const date = new Date(iso);
-  return date.toLocaleString(undefined, {
-    weekday: 'short',
-    month: 'short',
-    day: 'numeric',
-    year: 'numeric',
-    hour: 'numeric',
-    minute: '2-digit',
-  });
+function formatHistoryTimestamp(iso: string, locale: string): string {
+  return formatAppDateTime(iso, locale, APP_DATE.history);
 }
 
 export function PastTreatmentsPanel({
@@ -50,6 +44,7 @@ export function PastTreatmentsPanel({
   onSelectTreatment,
   compact = false,
 }: PastTreatmentsPanelProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
   const [notShippedOnly, setNotShippedOnly] = useState(false);
   const [filterDate, setFilterDate] = useState('');
@@ -71,7 +66,7 @@ export function PastTreatmentsPanel({
     setFilterDate('');
   }
 
-  const filterInputClass = `${FORM_SELECT_CLASS} rounded-md px-2 py-1.5 text-xs min-w-[9.5rem]`;
+  const filterInputClass = `${FORM_SELECT_CLASS} rounded-md py-1.5 text-xs min-w-[9.5rem]`;
 
   const filtersBlock = (
     <div
@@ -89,10 +84,9 @@ export function PastTreatmentsPanel({
         <span className="text-xs font-medium text-text-muted whitespace-nowrap">
           {t('historyFilterDate')}
         </span>
-        <input
-          type="date"
+        <AppDateInput
           value={filterDate}
-          onChange={(e) => setFilterDate(e.target.value)}
+          onChange={setFilterDate}
           className={filterInputClass}
         />
       </label>
@@ -156,7 +150,7 @@ export function PastTreatmentsPanel({
                   className="text-xs font-medium text-text-primary tabular-nums"
                   dateTime={treatment.treatmentAt}
                 >
-                  {formatHistoryTimestamp(treatment.treatmentAt)}
+                  {formatHistoryTimestamp(treatment.treatmentAt, locale)}
                 </time>
                 {isLiveDraft ? (
                   <span className="text-[10px] font-medium uppercase tracking-wide text-primary">
diff --git a/frontend/src/components/ui/treatment/TreatmentPreviewCard.tsx b/frontend/src/components/ui/treatment/TreatmentPreviewCard.tsx
index 79da58f..4cf7966 100644
--- a/frontend/src/components/ui/treatment/TreatmentPreviewCard.tsx
+++ b/frontend/src/components/ui/treatment/TreatmentPreviewCard.tsx
@@ -1,7 +1,8 @@
 'use client';
 
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { TreatmentDetailSummaryRow } from '@/components/ui/treatment/TreatmentDetailSummaryRow';
+import { APP_DATE, formatAppDate } from '@/lib/i18n/format';
 import type { LinkedOrganizationOption, PastTreatment } from '@/types/treatment';
 import type { TreatmentCatalogEntry } from '@/types/treatment-catalog';
 
@@ -23,6 +24,7 @@ export function TreatmentPreviewCard({
   orgs,
   embedded = false,
 }: TreatmentPreviewCardProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
 
   return (
@@ -38,12 +40,7 @@ export function TreatmentPreviewCard({
               className="text-xs text-text-muted tabular-nums block"
               dateTime={treatment.treatmentAt}
             >
-              {new Date(treatment.treatmentAt).toLocaleDateString(undefined, {
-                weekday: 'short',
-                year: 'numeric',
-                month: 'short',
-                day: 'numeric',
-              })}
+              {formatAppDate(treatment.treatmentAt, locale, APP_DATE.withWeekday)}
             </time>
           ) : null}
           <div className="space-y-2 max-h-[min(280px,40vh)] overflow-y-auto pr-1">
diff --git a/frontend/src/components/ui/treatment/TreatmentRailSection.tsx b/frontend/src/components/ui/treatment/TreatmentRailSection.tsx
index 19e893e..1a8da3f 100644
--- a/frontend/src/components/ui/treatment/TreatmentRailSection.tsx
+++ b/frontend/src/components/ui/treatment/TreatmentRailSection.tsx
@@ -28,7 +28,7 @@ export function TreatmentRailSection({
       : 'surface-card';
 
   return (
-    <section className={`${shellClass} overflow-hidden`}>
+    <section className={`treatment-rail-section ${shellClass} overflow-hidden`}>
       <button
         type="button"
         onClick={() => setExpanded((open) => !open)}
diff --git a/frontend/src/components/ui/treatment/TreatmentWorkspace.tsx b/frontend/src/components/ui/treatment/TreatmentWorkspace.tsx
index e4e7e0e..284e86d 100644
--- a/frontend/src/components/ui/treatment/TreatmentWorkspace.tsx
+++ b/frontend/src/components/ui/treatment/TreatmentWorkspace.tsx
@@ -1,7 +1,7 @@
 'use client';
 
 import { useCallback, useEffect, useMemo, useRef, useState } from 'react';
-import { useTranslations } from 'next-intl';
+import { useLocale, useTranslations } from 'next-intl';
 import { useRouter } from '@/i18n/navigation';
 import { Button } from '@/components/ui/shared/Button';
 import { Checkbox } from '@/components/ui/shared/Checkbox';
@@ -46,6 +46,7 @@ import { scrollWithinMainScrollContainer } from '@/components/shared/scrollWithi
 import { useMarkTabReadOnVisit, useTabBadgeCounts } from '@/lib/hooks/useTabBadgeCounts';
 import { tabBadgesChangedEventName } from '@/lib/tabBadgeUtils';
 import { notifyTabBadgesChanged } from '@/lib/tabBadgeUtils';
+import { APP_DATE, formatAppDate } from '@/lib/i18n/format';
 import { useAuth } from '@/lib/hooks/useAuth';
 import { getUserFacingError } from '@/components/shared/formatApiError';
 import { useToast } from '@/lib/hooks/useToast';
@@ -284,13 +285,13 @@ export function TreatmentWorkspace({
   currentOrganization,
   initialAppointmentId = null,
 }: TreatmentWorkspaceProps) {
+  const locale = useLocale();
   const t = useTranslations('treatment');
   const tErrors = useTranslations('errors');
   const tPatients = useTranslations('patients');
   const router = useRouter();
   const { user } = useAuth();
   const { showError, showSuccess, messages: toastMessages } = useToast();
-  const locale = user?.language ?? 'en';
   const canView = canViewTreatment(currentOrganization);
   const canEdit = canEditTreatment(currentOrganization);
   useMarkTabReadOnVisit();
@@ -1571,7 +1572,7 @@ export function TreatmentWorkspace({
         </p>
       )}
 
-      <div className="grid grid-cols-1 xl:grid-cols-[minmax(300px,380px)_minmax(0,1fr)] gap-4 items-start">
+      <div className="treatment-layout-grid grid grid-cols-1 xl:grid-cols-[minmax(300px,380px)_minmax(0,1fr)] gap-4 items-start">
         <div className="space-y-3 min-w-0 xl:max-w-[380px]">
           <div className="surface-card p-3 space-y-3">
             <PatientSearchCombobox
@@ -1619,12 +1620,7 @@ export function TreatmentWorkspace({
               <div className="rounded-[var(--radius-md)] border border-primary/40 bg-primary/5 px-3 py-2 space-y-2">
                 <p className="text-xs text-text-primary">
                   {t('browseBanner', {
-                    date: new Date(previewTreatment.treatmentAt).toLocaleDateString(undefined, {
-                      weekday: 'short',
-                      year: 'numeric',
-                      month: 'short',
-                      day: 'numeric',
-                    }),
+                    date: formatAppDate(previewTreatment.treatmentAt, locale, APP_DATE.withWeekday),
                   })}
                 </p>
                 <div className="flex flex-wrap gap-2">
diff --git a/frontend/src/i18n/routing.ts b/frontend/src/i18n/routing.ts
index 9df3ce2..6f8608a 100644
--- a/frontend/src/i18n/routing.ts
+++ b/frontend/src/i18n/routing.ts
@@ -5,6 +5,13 @@ export type AppLocale = (typeof locales)[number];
 
 export const defaultLocale: AppLocale = 'en';
 
+// Include future RTL locales here (e.g. 'ar') when added.
+export const rtlLocales = ['fa'] as const satisfies readonly AppLocale[];
+
+export function isRtlLocale(locale: string): boolean {
+  return (rtlLocales as readonly string[]).includes(locale);
+}
+
 export const routing = defineRouting({
   locales,
   defaultLocale,
diff --git a/frontend/src/lib/hooks/useAppFormatters.ts b/frontend/src/lib/hooks/useAppFormatters.ts
new file mode 100644
index 0000000..4343ead
--- /dev/null
+++ b/frontend/src/lib/hooks/useAppFormatters.ts
@@ -0,0 +1,45 @@
+'use client';
+
+import { useMemo } from 'react';
+import { useLocale } from 'next-intl';
+import {
+  APP_DATE,
+  formatAppDate,
+  formatAppDateTime,
+  formatAppNumber,
+  formatAppTableDate,
+  formatAppTime,
+  formatAppTimeRange,
+  createAppDateFormatter,
+} from '@/lib/i18n/format';
+
+export function useAppFormatters() {
+  const locale = useLocale();
+
+  return useMemo(
+    () => ({
+      locale,
+      formatDate: (value: Parameters<typeof formatAppDate>[0], options?: Intl.DateTimeFormatOptions) =>
+        formatAppDate(value, locale, options),
+      formatTime: (value: Parameters<typeof formatAppTime>[0], options?: Intl.DateTimeFormatOptions) =>
+        formatAppTime(value, locale, options),
+      formatDateTime: (
+        value: Parameters<typeof formatAppDateTime>[0],
+        options?: Intl.DateTimeFormatOptions,
+      ) => formatAppDateTime(value, locale, options),
+      formatTimeRange: (
+        start: Parameters<typeof formatAppTimeRange>[0],
+        end: Parameters<typeof formatAppTimeRange>[1],
+        options?: Intl.DateTimeFormatOptions,
+      ) => formatAppTimeRange(start, end, locale, options),
+      formatTableDate: (value: Parameters<typeof formatAppTableDate>[0]) =>
+        formatAppTableDate(value, locale),
+      formatNumber: (value: number, options?: Intl.NumberFormatOptions) =>
+        formatAppNumber(value, locale, options),
+      dateFormatter: (options: Intl.DateTimeFormatOptions = APP_DATE.chartDay) =>
+        createAppDateFormatter(locale, options),
+      presets: APP_DATE,
+    }),
+    [locale],
+  );
+}
diff --git a/frontend/src/lib/i18n/dateInputFormat.ts b/frontend/src/lib/i18n/dateInputFormat.ts
new file mode 100644
index 0000000..aeda0ab
--- /dev/null
+++ b/frontend/src/lib/i18n/dateInputFormat.ts
@@ -0,0 +1,43 @@
+import { toLatinDigits } from '@/lib/i18n/persianCalendar';
+
+/** Force `YYYY-MM-DD` shape while typing (Latin digits). */
+export function maskGregorianDateTyping(raw: string): string {
+  const digits = toLatinDigits(raw).replace(/\D/g, '').slice(0, 8);
+  const segments: string[] = [];
+  if (digits.length > 0) segments.push(digits.slice(0, Math.min(4, digits.length)));
+  if (digits.length > 4) segments.push(digits.slice(4, Math.min(6, digits.length)));
+  if (digits.length > 6) segments.push(digits.slice(6, 8));
+  return segments.join('-');
+}
+
+/** Parse typed Gregorian `YYYY-MM-DD` (slashes OK) → `YYYY-MM-DD` or null. */
+export function parseGregorianDateInputText(raw: string): string | null {
+  const normalized = toLatinDigits(raw.trim()).replace(/\//g, '-');
+  const match = /^(\d{4})-(\d{1,2})-(\d{1,2})$/.exec(normalized);
+  if (!match) return null;
+
+  const year = Number(match[1]);
+  const month = Number(match[2]);
+  const day = Number(match[3]);
+  if (month < 1 || month > 12 || day < 1) return null;
+
+  const date = new Date(year, month - 1, day, 0, 0, 0, 0);
+  if (
+    date.getFullYear() !== year ||
+    date.getMonth() !== month - 1 ||
+    date.getDate() !== day
+  ) {
+    return null;
+  }
+
+  const gm = String(month).padStart(2, '0');
+  const gd = String(day).padStart(2, '0');
+  return `${year}-${gm}-${gd}`;
+}
+
+/** `YYYY-MM-DD` → typed Gregorian field text. */
+export function formatIsoAsGregorianDateInput(iso: string): string {
+  if (!iso) return '';
+  const match = /^(\d{4})-(\d{2})-(\d{2})$/.exec(iso);
+  return match ? iso : '';
+}
diff --git a/frontend/src/lib/i18n/format.ts b/frontend/src/lib/i18n/format.ts
new file mode 100644
index 0000000..b889e59
--- /dev/null
+++ b/frontend/src/lib/i18n/format.ts
@@ -0,0 +1,157 @@
+import { isAppLocale, localeHtmlLang } from '@/i18n/routing';
+import { getLocalPersianParts } from '@/lib/i18n/persianCalendar';
+
+export const FORMAT_EMPTY = '—';
+
+/** BCP 47 tag for Intl APIs (`fa` → `fa-IR`, etc.). */
+export function intlLocale(locale: string): string {
+  return isAppLocale(locale) ? localeHtmlLang(locale) : locale;
+}
+
+export function usesPersianCalendar(locale: string): boolean {
+  return locale === 'fa';
+}
+
+function withPersianCalendar(
+  locale: string,
+  options: Intl.DateTimeFormatOptions,
+): Intl.DateTimeFormatOptions {
+  if (!usesPersianCalendar(locale)) {
+    return options;
+  }
+  return { calendar: 'persian', numberingSystem: 'arabext', ...options };
+}
+
+export function toValidDate(value: Date | string | number | null | undefined): Date | null {
+  if (value == null) return null;
+  const date = value instanceof Date ? value : new Date(value);
+  return Number.isNaN(date.getTime()) ? null : date;
+}
+
+export function createAppDateFormatter(
+  locale: string,
+  options: Intl.DateTimeFormatOptions = {},
+): Intl.DateTimeFormat {
+  return new Intl.DateTimeFormat(intlLocale(locale), withPersianCalendar(locale, options));
+}
+
+export const APP_DATE = {
+  short: { year: 'numeric', month: 'short', day: 'numeric' } satisfies Intl.DateTimeFormatOptions,
+  withWeekday: {
+    weekday: 'short',
+    year: 'numeric',
+    month: 'short',
+    day: 'numeric',
+  } satisfies Intl.DateTimeFormatOptions,
+  dayPicker: {
+    weekday: 'short',
+    month: 'short',
+    day: 'numeric',
+    year: 'numeric',
+  } satisfies Intl.DateTimeFormatOptions,
+  chartDay: { weekday: 'short', month: 'short', day: 'numeric' } satisfies Intl.DateTimeFormatOptions,
+  history: {
+    weekday: 'short',
+    month: 'short',
+    day: 'numeric',
+    year: 'numeric',
+    hour: 'numeric',
+    minute: '2-digit',
+  } satisfies Intl.DateTimeFormatOptions,
+  activity: {
+    month: 'short',
+    day: 'numeric',
+    hour: '2-digit',
+    minute: '2-digit',
+  } satisfies Intl.DateTimeFormatOptions,
+} as const;
+
+export function formatAppDate(
+  value: Date | string | number | null | undefined,
+  locale: string,
+  options: Intl.DateTimeFormatOptions = APP_DATE.short,
+): string {
+  const date = toValidDate(value);
+  if (!date) return FORMAT_EMPTY;
+  return createAppDateFormatter(locale, options).format(date);
+}
+
+export function formatAppTime(
+  value: Date | string | number | null | undefined,
+  locale: string,
+  options: Intl.DateTimeFormatOptions = { hour: 'numeric', minute: '2-digit' },
+): string {
+  const date = toValidDate(value);
+  if (!date) return FORMAT_EMPTY;
+  const timeOptions: Intl.DateTimeFormatOptions = {
+    ...options,
+    ...(usesPersianCalendar(locale) ? { numberingSystem: 'arabext' } : {}),
+  };
+  return new Intl.DateTimeFormat(intlLocale(locale), timeOptions).format(date);
+}
+
+export function formatAppDateTime(
+  value: Date | string | number | null | undefined,
+  locale: string,
+  options: Intl.DateTimeFormatOptions = { dateStyle: 'medium', timeStyle: 'short' },
+): string {
+  const date = toValidDate(value);
+  if (!date) return FORMAT_EMPTY;
+  return new Intl.DateTimeFormat(intlLocale(locale), withPersianCalendar(locale, options)).format(date);
+}
+
+export function formatAppTimeRange(
+  start: Date | string | number,
+  end: Date | string | number,
+  locale: string,
+  options: Intl.DateTimeFormatOptions = { hour: 'numeric', minute: '2-digit' },
+): string {
+  return `${formatAppTime(start, locale, options)} – ${formatAppTime(end, locale, options)}`;
+}
+
+/** Schedule axis labels (hour/minute from midnight). */
+export function formatAppMinuteOfDay(minute: number, locale: string): string {
+  const hours = Math.floor(minute / 60);
+  const minutes = minute % 60;
+  const date = new Date(2000, 0, 1, hours, minutes, 0, 0);
+  return formatAppTime(date, locale, {
+    hour: 'numeric',
+    minute: '2-digit',
+    hour12: !usesPersianCalendar(locale),
+  });
+}
+
+export function formatAppTableDate(
+  value: Date | string | number | null | undefined,
+  locale: string,
+): string {
+  return formatAppDate(value, locale, APP_DATE.short);
+}
+
+export function formatAppNumber(
+  value: number,
+  locale: string,
+  options?: Intl.NumberFormatOptions,
+): string {
+  return new Intl.NumberFormat(intlLocale(locale), options).format(value);
+}
+
+/** Calendar parts (year/day) — no thousands separators. */
+export function formatAppInteger(value: number, locale: string): string {
+  return new Intl.NumberFormat(intlLocale(locale), {
+    useGrouping: false,
+    ...(usesPersianCalendar(locale) ? { numberingSystem: 'arabext' } : {}),
+  }).format(value);
+}
+
+/** ScheduleDayPicker / calendar field trigger label — year without grouping. */
+export function formatAppPickerDateLabel(date: Date, locale: string): string {
+  const formatter = createAppDateFormatter(locale, APP_DATE.dayPicker);
+  const yearNum = usesPersianCalendar(locale)
+    ? getLocalPersianParts(date).year
+    : date.getFullYear();
+  return formatter
+    .formatToParts(date)
+    .map((part) => (part.type === 'year' ? formatAppInteger(yearNum, locale) : part.value))
+    .join('');
+}
diff --git a/frontend/src/lib/i18n/persianCalendar.ts b/frontend/src/lib/i18n/persianCalendar.ts
new file mode 100644
index 0000000..08c74c5
--- /dev/null
+++ b/frontend/src/lib/i18n/persianCalendar.ts
@@ -0,0 +1,214 @@
+/**
+ * Jalali (Persian) calendar — Gregorian `Date` values stay the app’s internal model.
+ * Conversion logic ported from jalaali-js (MIT).
+ */
+
+export type PersianDateParts = {
+  year: number;
+  month: number;
+  day: number;
+};
+
+const BREAKS = [
+  -61, 9, 38, 199, 426, 686, 756, 818, 1111, 1181, 1210, 1635, 2060, 2097, 2192, 2262,
+  2324, 2394, 2456, 3178,
+];
+
+function div(a: number, b: number): number {
+  return Math.trunc(a / b);
+}
+
+function mod(a: number, b: number): number {
+  return a - Math.trunc(a / b) * b;
+}
+
+function g2d(gy: number, gm: number, gd: number): number {
+  let d =
+    div((gy + div(gm - 8, 6) + 100100) * 1461, 4) +
+    div(153 * mod(gm + 9, 12) + 2, 5) +
+    gd -
+    34840408;
+  d = d - div(div(gy + 100100 + div(gm - 8, 6), 100) * 3, 4) + 752;
+  return d;
+}
+
+function d2g(jdn: number): { gy: number; gm: number; gd: number } {
+  let j = 4 * jdn + 139361631;
+  j = j + div(div(4 * jdn + 183187720, 146097) * 3, 4) * 4 - 3908;
+  const i = div(mod(j, 1461), 4) * 5 + 308;
+  const gd = div(mod(i, 153), 5) + 1;
+  const gm = mod(div(i, 153), 12) + 1;
+  const gy = div(j, 1461) - 100100 + div(8 - gm, 6);
+  return { gy, gm, gd };
+}
+
+function jalCal(jy: number, withoutLeap: boolean): { leap?: number; gy: number; march: number } {
+  const bl = BREAKS.length;
+  let gy = jy + 621;
+  let leapJ = -14;
+  let jp = BREAKS[0];
+  let jump = 0;
+  let leap = 0;
+  let n = 0;
+
+  if (jy < jp || jy >= BREAKS[bl - 1]) {
+    throw new Error(`Invalid Jalaali year ${jy}`);
+  }
+
+  for (let i = 1; i < bl; i += 1) {
+    const jm = BREAKS[i];
+    jump = jm - jp;
+    if (jy < jm) break;
+    leapJ = leapJ + div(jump, 33) * 8 + div(mod(jump, 33), 4);
+    jp = jm;
+  }
+  n = jy - jp;
+  leapJ = leapJ + div(n, 33) * 8 + div(mod(n, 33) + 3, 4);
+  if (mod(jump, 33) === 4 && jump - n === 4) leapJ += 1;
+
+  const leapG = div(gy, 4) - div((div(gy, 100) + 1) * 3, 4) - 150;
+  const march = 20 + leapJ - leapG;
+
+  if (withoutLeap) return { gy, march };
+
+  if (jump - n < 6) n = n - jump + div(jump + 4, 33) * 33;
+  leap = mod(mod(n + 1, 33) - 1, 4);
+  if (leap === -1) leap = 4;
+  return { leap, gy, march };
+}
+
+function j2d(jy: number, jm: number, jd: number): number {
+  const r = jalCal(jy, true);
+  return g2d(r.gy, 3, r.march) + (jm - 1) * 31 - div(jm, 7) * (jm - 7) + jd - 1;
+}
+
+function d2j(jdn: number): { jy: number; jm: number; jd: number } {
+  const { gy } = d2g(jdn);
+  let jy = gy - 621;
+  const r = jalCal(jy, false);
+  const jdn1f = g2d(gy, 3, r.march);
+  let k = jdn - jdn1f;
+  let jm: number;
+  let jd: number;
+
+  if (k >= 0) {
+    if (k <= 185) {
+      jm = 1 + div(k, 31);
+      jd = mod(k, 31) + 1;
+      return { jy, jm, jd };
+    }
+    k -= 186;
+  } else {
+    jy -= 1;
+    k += 179;
+    if (r.leap === 1) k += 1;
+  }
+  jm = 7 + div(k, 30);
+  jd = mod(k, 30) + 1;
+  return { jy, jm, jd };
+}
+
+export function gregorianToJalali(gy: number, gm: number, gd: number): [number, number, number] {
+  const { jy, jm, jd } = d2j(g2d(gy, gm, gd));
+  return [jy, jm, jd];
+}
+
+export function jalaliToGregorian(jy: number, jm: number, jd: number): [number, number, number] {
+  const { gy, gm, gd } = d2g(j2d(jy, jm, jd));
+  return [gy, gm, gd];
+}
+
+export function isJalaliLeapYear(jy: number): boolean {
+  const r = jalCal(jy, false);
+  return r.leap === 0;
+}
+
+export function jalaliDaysInMonth(jy: number, jm: number): number {
+  if (jm <= 6) return 31;
+  if (jm <= 11) return 30;
+  return isJalaliLeapYear(jy) ? 30 : 29;
+}
+
+export function getLocalPersianParts(date: Date): PersianDateParts {
+  const [year, month, day] = gregorianToJalali(
+    date.getFullYear(),
+    date.getMonth() + 1,
+    date.getDate(),
+  );
+  return { year, month, day };
+}
+
+export function persianPartsToLocalDate(jy: number, jm: number, jd: number): Date {
+  const [gy, gm, gd] = jalaliToGregorian(jy, jm, jd);
+  return new Date(gy, gm - 1, gd, 0, 0, 0, 0);
+}
+
+export function persianYearRange(anchorYear: number, past = 10, future = 2): number[] {
+  const years: number[] = [];
+  for (let y = anchorYear - past; y <= anchorYear + future; y += 1) {
+    years.push(y);
+  }
+  return years;
+}
+
+const persianMonthFormatter = new Intl.DateTimeFormat('fa-IR-u-ca-persian', {
+  month: 'long',
+  numberingSystem: 'arabext',
+});
+
+/** Jalali month name (Farvardin, …) for picker labels. */
+export function formatPersianMonthLabel(jy: number, jm: number): string {
+  const [gy, gm, gd] = jalaliToGregorian(jy, jm, 15);
+  return persianMonthFormatter.format(new Date(gy, gm - 1, gd));
+}
+
+const ARABEXT_DIGITS = ['۰', '۱', '۲', '۳', '۴', '۵', '۶', '۷', '۸', '۹'] as const;
+
+export function toLatinDigits(value: string): string {
+  return value.replace(/[۰-۹]/g, (ch) => {
+    const index = ARABEXT_DIGITS.indexOf(ch as (typeof ARABEXT_DIGITS)[number]);
+    return index >= 0 ? String(index) : ch;
+  });
+}
+
+export function toArabextDigits(value: string): string {
+  return value.replace(/\d/g, (d) => ARABEXT_DIGITS[Number(d)] ?? d);
+}
+
+/** Parse typed Jalali `YYYY/MM/DD` (Latin or Persian digits) → `YYYY-MM-DD` or null. */
+export function parsePersianDateInputText(raw: string): string | null {
+  const normalized = toLatinDigits(raw.trim()).replace(/-/g, '/');
+  const match = /^(\d{4})\/(\d{1,2})\/(\d{1,2})$/.exec(normalized);
+  if (!match) return null;
+
+  const jy = Number(match[1]);
+  const jm = Number(match[2]);
+  const jd = Number(match[3]);
+  if (jm < 1 || jm > 12 || jd < 1 || jd > jalaliDaysInMonth(jy, jm)) return null;
+
+  const date = persianPartsToLocalDate(jy, jm, jd);
+  const gy = date.getFullYear();
+  const gm = String(date.getMonth() + 1).padStart(2, '0');
+  const gd = String(date.getDate()).padStart(2, '0');
+  return `${gy}-${gm}-${gd}`;
+}
+
+/** `YYYY-MM-DD` → typed Jalali field text e.g. ۱۴۰۴/۰۴/۲۲ */
+export function formatIsoAsPersianDateInput(iso: string): string {
+  if (!iso) return '';
+  const [gy, gm, gd] = iso.split('-').map(Number);
+  if (!gy || !gm || !gd) return '';
+  const { year, month, day } = getLocalPersianParts(new Date(gy, gm - 1, gd, 0, 0, 0, 0));
+  const pad2 = (n: number) => toArabextDigits(String(n).padStart(2, '0'));
+  return `${toArabextDigits(String(year))}/${pad2(month)}/${pad2(day)}`;
+}
+
+/** Force `YYYY/MM/DD` shape while typing (Persian digits in output). */
+export function maskJalaliDateTyping(raw: string): string {
+  const digits = toLatinDigits(raw).replace(/\D/g, '').slice(0, 8);
+  const segments: string[] = [];
+  if (digits.length > 0) segments.push(digits.slice(0, Math.min(4, digits.length)));
+  if (digits.length > 4) segments.push(digits.slice(4, Math.min(6, digits.length)));
+  if (digits.length > 6) segments.push(digits.slice(6, 8));
+  return toArabextDigits(segments.join('/'));
+}
diff --git a/frontend/src/lib/labCaseActivityLabels.ts b/frontend/src/lib/labCaseActivityLabels.ts
index 772c505..4dd40c3 100644
--- a/frontend/src/lib/labCaseActivityLabels.ts
+++ b/frontend/src/lib/labCaseActivityLabels.ts
@@ -1,4 +1,5 @@
 import type { LabCaseActivityItem } from '@/types/lab-case-activity';
+import { APP_DATE, formatAppDateTime } from '@/lib/i18n/format';
 
 type ActivityLabelTranslator = (
   key: string,
@@ -11,12 +12,7 @@ export function formatLabCaseActivityLine(
   locale: string,
 ): string {
   const actor = activity.actorName ?? t('activityUnknownActor');
-  const date = new Date(activity.createdAt).toLocaleString(locale, {
-    month: 'short',
-    day: 'numeric',
-    hour: '2-digit',
-    minute: '2-digit',
-  });
+  const date = formatAppDateTime(activity.createdAt, locale, APP_DATE.activity);
 
   switch (activity.type) {
     case 'CASE_SENT':
diff --git a/frontend/src/styles/globals.css b/frontend/src/styles/globals.css
index 048a7db..ca777a1 100644
--- a/frontend/src/styles/globals.css
+++ b/frontend/src/styles/globals.css
@@ -241,10 +241,34 @@ html[data-theme='light'] {
   color-scheme: light;
 }
 
+/* Minimal RTL layer — refine incrementally. */
+html[dir='rtl'] body {
+  direction: rtl;
+}
+
+/* Sidebar: don't rely on Tailwind rtl: variants. */
+html[dir='rtl'] .app-sidebar {
+  border-right: 0;
+  border-left: 1px solid var(--color-border);
+}
+
+/* Mobile drawer only — desktop sidebar follows flex + document direction. */
+@media (max-width: 1023px) {
+  html[dir='rtl'] .app-sidebar {
+    left: auto;
+    right: 0;
+  }
+}
+
+/* Treatment rail: align header text to the right in RTL. */
+html[dir='rtl'] .treatment-rail-section > button {
+  text-align: right;
+}
+
 body {
   background-color: var(--color-background-primary);
   color: var(--color-text-primary);
-  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
+  font-family: var(--font-sans, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif);
 }
 
 select.form-select,
@@ -254,6 +278,25 @@ select {
   font-size: 1rem;
 }
 
+/* Shared chevron for all `.form-select` — symmetric inset matches `ps-3` text padding. */
+select.form-select:not(.form-select-no-chevron) {
+  appearance: none;
+  -webkit-appearance: none;
+  text-align: start;
+  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
+  background-repeat: no-repeat;
+  background-size: 1rem 1rem;
+  background-position: right 0.75rem center;
+}
+
+html[dir='rtl'] select.form-select:not(.form-select-no-chevron) {
+  background-position: left 0.75rem center;
+}
+
+select.form-select.form-select-no-chevron {
+  background-image: none;
+}
+
 @media (min-width: 640px) {
   select.form-select,
   select {