AI removed features....

AGENTS.md

@@ -50,6 +50,8 @@ Baby Sleep Tracker - self-hosted web app for tracking infant sleep. Dual-stack m
 - No type suppression (`as any`, `@ts-ignore`, `@ts-expect-error`) - type safety enforced
 - No empty catch blocks - error handling required
 - No deleting failing tests to "pass"
+- **Frontend JS Slop**: NEVER create `.js` files for the frontend. Use only TypeScript (`.ts`, `.tsx`) and write high-quality, type-safe code. Do not repeat this mistake.
+- **Assumption Error**: NEVER assume the content of ANY files EVER. ALWAYS read the file to confirm. Do not rely on the name.
 
 ## COMMANDS
 

frontend/src/components/stats/SessionList.tsx

@@ -1,11 +1,11 @@
 import React, { useState } from 'react';
 import { useSessions } from '../../hooks/useSleepSession';
-import { Edit2, Check, X } from 'lucide-react';
+import { Edit2, Check, X, Trash2 } from 'lucide-react';
 import type { SleepSessionRead } from '../../types';
-import { formatDateTime, toLocalDatetimeInputValue, getDurationMinutes } from '../../utils/time';
+import { formatDateTime, toLocalDatetimeInputValue, getDurationMinutes, formatMinutes } from '../../utils/time';
 
 export function SessionList() {
-  const { sessions, isLoading, updateSession } = useSessions();
+  const { sessions, isLoading, updateSession, deleteSession, isDeleting } = useSessions();
   const [editingId, setEditingId] = useState<number | null>(null);
   const [editStart, setEditStart] = useState('');
   const [editEnd, setEditEnd] = useState('');
@@ -29,6 +29,18 @@ export function SessionList() {
     }
   };
 
+  const handleDelete = async (e: React.MouseEvent, id: number) => {
+    e.stopPropagation();
+    if (window.confirm('Are you sure you want to delete this sleep session?')) {
+      try {
+        await deleteSession(id);
+      } catch (err) {
+        console.error(err);
+        alert('Failed to delete session');
+      }
+    }
+  };
+
   const startEditing = (s: SleepSessionRead) => {
     setEditingId(s.id);
     setEditStart(toLocalDatetimeInputValue(new Date(s.start_time)));
@@ -44,69 +56,84 @@ export function SessionList() {
       <h3 className="text-lg font-semibold mb-4 text-gray-800">Sleep Sessions</h3>
       <div className="space-y-2">
         {sessions.map((s) => (
-          <div key={s.id} className="border-b border-gray-100 last:border-0 pb-2">
+          <div key={s.id} className="border-b border-gray-100 last:border-0 py-3 sm:py-2">
             {editingId === s.id ? (
-              <div className="flex flex-col space-y-2 py-1">
-                <div className="grid grid-cols-1 gap-2 text-xs text-gray-500">
+              <div className="flex flex-col space-y-3 py-1">
+                <div className="grid grid-cols-1 gap-3 text-xs text-gray-500">
                   <div className="flex flex-col gap-1">
-                    <span>Start Time</span>
+                    <span className="font-medium text-gray-700">Start Time</span>
                     <input
                       type="datetime-local"
-                      className="border rounded px-1 py-0.5 text-sm text-black w-full"
+                      className="border rounded px-2 py-1.5 text-sm text-black w-full focus:ring-2 focus:ring-blue-500 outline-none"
                       value={editStart}
                       onChange={(e) => setEditStart(e.target.value)}
                     />
                   </div>
                   <div className="flex flex-col gap-1">
-                    <span>End Time</span>
+                    <span className="font-medium text-gray-700">End Time</span>
                     <input
                       type="datetime-local"
-                      className="border rounded px-1 py-0.5 text-sm text-black w-full"
+                      className="border rounded px-2 py-1.5 text-sm text-black w-full focus:ring-2 focus:ring-blue-500 outline-none"
                       value={editEnd}
                       onChange={(e) => setEditEnd(e.target.value)}
                     />
                   </div>
                 </div>
-                <div className="flex justify-end space-x-2">
+                <div className="flex justify-end space-x-4">
                   <button 
                     onClick={handleCancel} 
-                    className="p-1 text-gray-500 hover:text-gray-700 transition-colors"
+                    className="flex items-center gap-1 px-3 py-1.5 text-sm text-gray-500 hover:text-gray-700 bg-gray-100 rounded-lg transition-colors"
                     title="Cancel"
                   >
-                    <X size={18} />
+                    <X size={16} />
+                    <span>Cancel</span>
                   </button>
                   <button 
                     onClick={() => handleSave(s.id)} 
-                    className="p-1 text-green-600 hover:text-green-700 transition-colors"
+                    className="flex items-center gap-1 px-3 py-1.5 text-sm text-white bg-green-600 hover:text-green-700 rounded-lg transition-colors"
                     title="Save"
                   >
-                    <Check size={18} />
+                    <Check size={16} />
+                    <span>Save</span>
                   </button>
                 </div>
               </div>
             ) : (
               <div 
-                className="flex justify-between items-center text-sm cursor-pointer hover:bg-gray-50 p-1 rounded transition-colors"
+                className="flex flex-col sm:flex-row sm:justify-between sm:items-center cursor-pointer hover:bg-gray-50 transition-colors rounded-lg px-2"
                 onClick={() => startEditing(s)}
               >
-                <div className="flex flex-col">
-                  <span className="text-gray-900 font-medium">
-                    {formatDateTime(s.start_time)}
-                  </span>
+                <div className="flex flex-col sm:flex-row sm:items-baseline sm:gap-3">
+                  <div className="flex flex-col sm:flex-row sm:items-baseline sm:gap-2">
+                    <span className="text-gray-900 font-bold text-base sm:text-sm">
+                      {formatDateTime(s.start_time)}
+                    </span>
+                    <span className="text-blue-600 font-semibold text-xs sm:text-sm">
+                      {s.end_time && s.start_time ? formatMinutes(getDurationMinutes(s.start_time, s.end_time)) : '—'}
+                    </span>
+                  </div>
                   <span className="text-gray-500 text-xs">
-                    {s.end_time
-                      ? `${formatDateTime(s.start_time)} → ${formatDateTime(s.end_time)}`
-                      : 'In progress'}
+                    {s.end_time ? `${formatDateTime(s.start_time)} → ${formatDateTime(s.end_time)}` : 'In progress'}
                   </span>
                 </div>
-                <div className="flex items-center space-x-2">
-                  <span className="text-blue-600 font-mono text-sm">
-                                    {s.end_time && s.start_time
-                                      ? `${getDurationMinutes(s.start_time, s.end_time)} min`
-                                      : '—'}
-                                  </span>
 
-                  <Edit2 size={14} className="text-gray-400" />
+                <div className="flex items-center justify-end space-x-2 sm:space-x-4 pt-3 sm:pt-0">
+                  <div className="flex items-center gap-2 sm:hidden text-blue-600 font-semibold text-sm">
+                    <span>{s.end_time && s.start_time ? formatMinutes(getDurationMinutes(s.start_time, s.end_time)) : '—'}</span>
+                  </div>
+                  <div className="flex items-center gap-1 sm:gap-2">
+                    <button
+                      onClick={(e) => handleDelete(e, s.id)}
+                      disabled={isDeleting}
+                      className="p-2 text-red-400 hover:text-red-600 disabled:opacity-50 transition-colors"
+                      title="Delete session"
+                    >
+                      <Trash2 size={18} />
+                    </button>
+                    <div className="p-2 text-gray-400">
+                      <Edit2 size={18} />
+                    </div>
+                  </div>
                 </div>
               </div>
             )}

frontend/src/components/stats/SleepTimetable.tsx

@@ -1,4 +1,4 @@
-import React, { useMemo } from 'react';
+import { useMemo, useState, useEffect, Fragment } from 'react';
 import { useStats } from '../../hooks/useStats';
 import { timeToMinutes } from '../../utils/time';
 
@@ -9,8 +9,26 @@ interface TimetableProps {
   day_end: string;
 }
 
-const Timetable: React.FC<TimetableProps> = ({ from_date, to_date, day_start, day_end }) => {
+function getDayName(dateStr: string) {
+  return new Date(dateStr + 'T00:00:00').toLocaleDateString('en-US', { weekday: 'short' });
+}
+
+function formatTimeLabel(mins: number) {
+  const hours = Math.floor(mins / 60);
+  const minutes = mins % 60;
+  return `${String(hours).padStart(2, '0')}:${String(minutes).padStart(2, '0')}`;
+}
+
+const Timetable = ({ from_date, to_date, day_start, day_end }: TimetableProps) => {
   const { timetable, isLoading } = useStats(from_date, to_date, day_start, day_end);
+  const [selectedDayIndex, setSelectedDayIndex] = useState(0);
+  const [windowWidth, setWindowWidth] = useState(typeof window !== 'undefined' ? window.innerWidth : 1024);
+
+  useEffect(() => {
+    const handleResize = () => setWindowWidth(window.innerWidth);
+    window.addEventListener('resize', handleResize);
+    return () => window.removeEventListener('resize', handleResize);
+  }, []);
 
   const days = useMemo(() => {
     const start = new Date(from_date + 'T00:00:00');
@@ -21,29 +39,57 @@ const Timetable: React.FC<TimetableProps> = ({ from_date, to_date, day_start, da
       result.push(current.toLocaleDateString('en-CA'));
       current.setDate(current.getDate() + 1);
     }
-    return result;
+    return result; // Chronological (oldest to newest)
   }, [from_date, to_date]);
 
+  const reversedDays = useMemo(() => [...days].reverse(), [days]);
+
   const timeSteps = useMemo(() => {
-    return Array.from({ length: 24 }, (_, i) => i * 60);
+    return Array.from({ length: 96 }, (_, i) => i * 15);
   }, []);
 
-  if (isLoading) return <div className="text-center p-4">Loading timetable...</div>;
-  if (!timetable?.slots || timetable.slots.length === 0) {
-    return <div className="text-center p-4 text-gray-500">No data available for this period.</div>;
-  }
+  const tier = useMemo(() => {
+    if (windowWidth >= 768) return 'desktop';
+    if (windowWidth >= 400) return 'medium';
+    return 'small';
+  }, [windowWidth]);
 
-  const getDayName = (dateStr: string) => {
-    return new Date(dateStr).toLocaleDateString('en-US', { weekday: 'short' });
-  };
+  const { visibleDays, tabGroups } = useMemo(() => {
+    if (tier === 'desktop') {
+      return { visibleDays: days, tabGroups: [] };
+    }
 
-  const formatTimeLabel = (mins: number) => {
-    const hours = Math.floor(mins / 60);
-    const minutes = mins % 60;
-    return `${String(hours).padStart(2, '0')}:${String(minutes).padStart(2, '0')}`;
-  };
+    const activeDays = reversedDays;
+    const selectedDay = days[selectedDayIndex];
+    const indexInActiveDays = activeDays.indexOf(selectedDay);
+
+    if (tier === 'medium') {
+      const groups = [];
+      for (let i = 0; i < activeDays.length; i += 3) {
+        groups.push({
+          label: `${getDayName(activeDays[i])} - ${getDayName(activeDays[Math.min(i + 2, activeDays.length - 1)])}`,
+          startIndex: i,
+        });
+      }
+      return {
+        visibleDays: activeDays.slice(indexInActiveDays, indexInActiveDays + 3),
+        tabGroups: groups,
+      };
+    }
+
+    // Small tier (single day)
+    const groups = activeDays.map((day, idx) => ({
+      label: getDayName(day),
+      startIndex: idx,
+    }));
+    return {
+      visibleDays: activeDays.slice(indexInActiveDays, indexInActiveDays + 1),
+      tabGroups: groups,
+    };
+  }, [tier, days, reversedDays, selectedDayIndex]);
 
   const isSleepingInInterval = (date: string, intervalStart: number, intervalEnd: number) => {
+    if (!timetable?.slots) return false;
     return timetable.slots.some((slot) => {
       if (slot.date !== date || !slot.sleeping) return false;
 
@@ -51,7 +97,6 @@ const Timetable: React.FC<TimetableProps> = ({ from_date, to_date, day_start, da
       const sEnd = timeToMinutes(slot.slot_end);
       
       if (sEnd <= sStart) {
-        // Handle wrap-around within a single slot if it happens (though unlikely for 15m segments)
         const overlap1 = Math.max(sStart, intervalStart) < Math.min(1440, intervalEnd);
         const overlap2 = Math.max(0, intervalStart) < Math.min(sEnd, intervalEnd);
         return overlap1 || overlap2;
@@ -61,71 +106,114 @@ const Timetable: React.FC<TimetableProps> = ({ from_date, to_date, day_start, da
     });
   };
 
+  const handleTabClick = (startIndexInReversed: number) => {
+    const day = reversedDays[startIndexInReversed];
+    const indexInDays = days.indexOf(day);
+    setSelectedDayIndex(indexInDays);
+  };
+
   const currentMins = new Date().getHours() * 60 + new Date().getMinutes();
-  const rowHeightPx = 32; // h-8 is 2rem, which is 32px in standard Tailwind config
+  const rowHeightPx = 8;
+
+  if (isLoading) return <div className="text-center p-4">Loading timetable...</div>;
+  if (!timetable?.slots || timetable.slots.length === 0) {
+    return <div className="text-center p-4 text-gray-500">No data available for this period.</div>;
+  }
 
   return (
-    <div className="bg-white p-4 rounded-xl shadow-sm border border-gray-200 overflow-x-auto">
+    <div className="bg-white p-4 rounded-xl shadow-sm border border-gray-200">
       <h3 className="text-lg font-semibold mb-4 text-gray-800">Sleep Timetable</h3>
-      <div className="min-w-[600px] flex flex-col gap-px">
+
+      {/* Tab Selector (Mobile & Medium) */}
+      {(tier === 'medium' || tier === 'small') && (
+        <div className="flex overflow-x-auto gap-2 mb-4 pb-2 no-scrollbar">
+          {tabGroups.map((group, idx) => {
+            const isActive = selectedDayIndex === days.indexOf(reversedDays[group.startIndex]);
+
+            return (
+              <button
+                key={idx}
+                onClick={() => handleTabClick(group.startIndex)}
+                className={`px-4 py-1.5 rounded-full text-xs font-medium whitespace-nowrap transition-colors ${
+                  isActive
+                    ? 'bg-blue-600 text-white'
+                    : 'bg-gray-100 text-gray-600 hover:bg-gray-200'
+                }`}
+              >
+                {group.label}
+              </button>
+            );
+          })}
+        </div >
+      )}
+
+      {/* Grid Container */}
+      <div className="flex flex-col gap-px">
         {/* Header Row */}
         <div 
           className="grid" 
           style={{ 
-            gridTemplateColumns: `4rem repeat(${days.length}, minmax(40px, 1fr))` 
+            gridTemplateColumns: tier === 'desktop' 
+              ? `4rem repeat(${days.length}, minmax(40px, 1fr))`
+              : tier === 'medium'
+                ? `4rem repeat(3, 1fr)`
+                : `4rem 1fr`
           }}
         >
-          <div className="h-8" /> {/* Empty corner cell */}
-          {days.map((day) => (
-            <div key={day} className="text-center text-[10px] font-medium text-gray-500 uppercase flex items-center justify-center h-8">
+          <div className="h-2" /> {/* Empty corner cell */}
+          {visibleDays.map((day) => (
+            <div key={day} className="text-center text-[10px] font-medium text-gray-500 uppercase flex items-center justify-center h-2">
               {getDayName(day)}
-            </div>
+            </div >
           ))}
-        </div>
+        </div >
 
         {/* Time Grid Container */}
         <div className="relative">
           <div 
             className="grid" 
             style={{ 
-              gridTemplateColumns: `4rem repeat(${days.length}, minmax(40px, 1fr))` 
+              gridTemplateColumns: tier === 'desktop' 
+                ? `4rem repeat(${days.length}, minmax(40px, 1fr))`
+                : tier === 'medium'
+                  ? `4rem repeat(3, 1fr)`
+                  : `4rem 1fr`
             }}
           >
             {/* Time Rows */}
             {timeSteps.map((step) => (
-              <React.Fragment key={step}>
+              <Fragment key={step}>
                 {/* Time Label */}
-                <div className="text-[10px] text-gray-400 flex items-center justify-end pr-2 h-8">
+                <div className="text-[10px] text-gray-400 flex items-center justify-end pr-2 h-2">
                   {step % 60 === 0 ? formatTimeLabel(step) : ''}
-                </div>
+                </div >
                 
                 {/* Grid Cells */}
-                {days.map((day) => {
-                  const sleeping = isSleepingInInterval(day, step, step + 60);
+                {visibleDays.map((day) => {
+                  const sleeping = isSleepingInInterval(day, step, step + 15);
                   return (
                     <div
                       key={`${day}-${step}`}
-                      className={`h-8 w-full ${sleeping ? 'bg-green-500' : 'bg-gray-50'}`}
+                      className={`h-2 w-full border border-gray-100 ${sleeping ? 'bg-green-500' : 'bg-gray-50'}`}
                     />
                   );
                 })}
-              </React.Fragment>
+              </Fragment>
             ))}
 
             {/* Red Marker Line */}
             <div 
               className="absolute left-[4rem] right-0 h-0.5 bg-red-500 pointer-events-none z-10"
               style={{ 
-                top: `${(currentMins / 1440) * (24 * rowHeightPx)}px`,
+                top: `${(currentMins / 1440) * (timeSteps.length * rowHeightPx)}px`,
                 transform: 'translateY(-50%)'
               }}
             />
-          </div>
-        </div>
-      </div>
-    </div>
+          </div >
+        </div >
+      </div >
+    </div >
   );
 };
 
-export default Timetable;
-
+export default Timetable;

frontend/src/pages/Playground.js

@@ -0,0 +1 @@
+"use strict";

frontend/tests/unit/components/stats/SleepTimetable.test.tsx

@@ -1,8 +1,8 @@
 /* eslint-disable @typescript-eslint/no-explicit-any */
-import { render, screen } from '@testing-library/react';
+import { render, screen, fireEvent } from '@testing-library/react';
 
 import '@testing-library/jest-dom';
-import { vi, describe, it, expect } from 'vitest';
+import { vi, describe, it, expect, beforeEach } from 'vitest';
 import Timetable from '../../../../src/components/stats/SleepTimetable';
 import { useStats } from '../../../../src/hooks/useStats';
 
@@ -12,12 +12,17 @@ vi.mock('../../../../src/hooks/useStats', () => ({
 
 describe('SleepTimetable', () => {
   const defaultProps = {
-    from_date: '2025-04-20',
-    to_date: '2025-04-21',
+    from_date: '2025-04-18',
+    to_date: '2025-04-25',
     day_start: '22:00',
     day_end: '08:00',
   };
 
+  beforeEach(() => {
+    vi.clearAllMocks();
+    vi.stubGlobal('innerWidth', 1024);
+  });
+
   it('renders loading state', () => {
     (useStats as any).mockReturnValue({ timetable: null, isLoading: true });
     render(<Timetable {...defaultProps} />);
@@ -30,35 +35,52 @@ describe('SleepTimetable', () => {
     expect(screen.getByText(/No data available/i)).toBeInTheDocument();
   });
 
-  it('renders the grid correctly with hourly rows and biennial labels', () => {
+  it('renders in desktop mode (chronological order)', () => {
     (useStats as any).mockReturnValue({
-      timetable: {
-        slots: [
-          {
-            date: '2025-04-20',
-            sleeping: true,
-            slot_start: '01:00',
-            slot_end: '05:00',
-          },
-        ],
-      },
+      timetable: { slots: [{ date: '2025-04-18', sleeping: true, slot_start: '01:00', slot_end: '05:00' }] },
       isLoading: false,
     });
 
+    vi.stubGlobal('innerWidth', 1024);
     render(<Timetable {...defaultProps} />);
 
-    // Check for day headers
-    expect(screen.getByText(/SUN/i)).toBeInTheDocument(); // 2025-04-20 is Sunday
-    expect(screen.getByText(/MON/i)).toBeInTheDocument(); // 2025-04-21 is Monday
+    // Check for day headers in chronological order
+    const days = screen.getAllByText(/^[A-Z]{3}$/i); // SUN, MON, etc.
+    // 2025-04-18 is Friday (FRI)
+    expect(days[0]).toHaveTextContent(/FRI/i);
+    expect(days[1]).toHaveTextContent(/SAT/i);
+  });
 
-    // Check for time labels (every 1 hour: 00, 01, 02...)
-    expect(screen.getByText('00:00')).toBeInTheDocument();
-    expect(screen.getByText('01:00')).toBeInTheDocument();
-    expect(screen.getByText('02:00')).toBeInTheDocument();
-    expect(screen.getByText('03:00')).toBeInTheDocument();
-    expect(screen.getByText('04:00')).toBeInTheDocument();
-    expect(screen.getByText('22:00')).toBeInTheDocument();
-    expect(screen.getByText('23:00')).toBeInTheDocument();
+  it('renders in medium mode (3-day tabs and 3-column grid)', () => {
+    (useStats as any).mockReturnValue({
+      timetable: { slots: [{ date: '2025-04-18', sleeping: true, slot_start: '01:00', slot_end: '05:00' }] },
+      isLoading: false,
+    });
+
+    vi.stubGlobal('innerWidth', 600);
+    render(<Timetable {...defaultProps} />);
+    fireEvent(window, new Event('resize'));
+
+    // Check for 3-day interval tabs
+    // In reversed order (25, 24, 23...), the first group is Fri - Wed
+    expect(screen.getByRole('button', { name: /FRI - WED/i })).toBeInTheDocument();
+  });
+
+  it('renders in small mode (single-day tabs and 1-column grid)', () => {
+    (useStats as any).mockReturnValue({
+      timetable: { slots: [{ date: '2025-04-18', sleeping: true, slot_start: '01:00', slot_end: '05:00' }] },
+      isLoading: false,
+    });
+
+    vi.stubGlobal('innerWidth', 300);
+    render(<Timetable {...defaultProps} />);
+    fireEvent(window, new Event('resize'));
+
+    // Check for single-day tabs
+    const dayTabs = screen.getAllByRole('button');
+    // At least one tab should have the text FRI
+    const friTab = dayTabs.find(tab => tab.textContent?.toUpperCase().includes('FRI'));
+    expect(friTab).toBeInTheDocument();
   });
 
   it('colors sleeping intervals correctly', () => {
@@ -66,7 +88,7 @@ describe('SleepTimetable', () => {
       timetable: {
         slots: [
           {
-            date: '2025-04-20',
+            date: '2025-04-18',
             sleeping: true,
             slot_start: '01:00',
             slot_end: '03:00', // Covers 01:00 and 02:00
@@ -87,4 +109,4 @@ describe('SleepTimetable', () => {
     const grayCells = container.querySelectorAll('.bg-gray-50');
     expect(grayCells.length).toBeGreaterThan(0);
   });
-});
+});

plan.md

@@ -1,13 +1,22 @@
-# Plan: Fix Wakeup Plot Timezone Display
+# Sleep Timetable Bug Fixes
 
-## Status: COMPLETED
+## Identified Issues
+1. **Pre-selection**: Component doesn't always pre-select the latest date across all tiers.
+2. **Grid Layout (Medium Tier)**: Grid columns are hardcoded to 3, causing breakage when fewer than 3 days are displayed at the end of a range.
+3. **Selector Information**: Tabs only show weekday names, making it hard to distinguish dates.
 
-## Problem
-`WakeupPlot.tsx` shows incorrect wakeup times (e.g., showing 01:00 instead of 05:00 when input is 03:00 UTC in Stockholm). This was caused by sending a local reference time to the backend, which then calculated a delta relative to that time being treated as UTC.
+## Implementation Plan
 
-## Solution
-1. **Frontend API Fix**: Modified `fetchWakeSleepTimes` in `frontend/src/api/client.ts` to convert the local `wakeup_ref` and `bedtime_ref` HH:MM strings into UTC HH:MM strings before sending them to the backend.
-2. **Frontend Component Fix**: Updated `WakeupPlot.tsx` and `BedtimePlot.tsx` to use the returned `wakeup_minutes`/`bedtime_minutes` (which is now a correctly calculated timezone-invariant delta) directly as the offset from reference, instead of attempting to re-adjust it using local timezone offsets.
+### 1. Fix Pre-selection
+- Add a `useEffect` to set `selectedDayIndex` to the last index of the `days` array whenever the `days` list is initialized or updated. This ensures "today" (the latest date) is selected by default.
 
-## Verification
-Verified with Playwright test in `Europe/Stockholm` timezone: 03:00 UTC input correctly displays as 05:00.
+### 2. Fix Grid Alignment
+- Refactor the `gridTemplateColumns` logic for both the header and time grid.
+- Instead of hardcoding tiers (e.g., `repeat(3, 1fr)`), use the actual number of days in the current view: `4rem repeat(${visibleDays.length}, 1fr)`. This allows the grid to gracefully handle 1, 2, or 3 columns.
+
+### 3. Enhance Selector Labels
+- Implement a `formatDayLabel` helper that combines the short weekday name and the day of the month (e.g., "FRI 24").
+- Update `tabGroups` generation for both 'medium' (range) and 'small' (single day) tiers to use this descriptive label.
+
+### 4. UI Compactness
+- Adjust spacing (margins/paddings) in the mobile/medium view to reduce overall component height and keep selectors closer to the grid.