refactor: major architecture improvements

Security:
- Remove exposed NocoDB token from client code
- Add .env.example for environment variables

Shared Components:
- Carousel: touch/keyboard navigation, accessibility
- ChartCard: reusable chart container
- EmptyState: for no-data scenarios
- FilterControls: collapsible filter panel with reset button
- StatCard: metric display with change indicator
- ToggleSwitch: accessible radio-style toggle

Architecture:
- Create src/config/chartConfig.js for shared chart options
- Extract ChartJS registration to single location
- Reduce code duplication in Dashboard and Comparison

UX Improvements:
- Add empty state when filters return no data
- Add Reset Filters button to filter controls
- Add skeleton loader CSS utilities
- Improve focus states for accessibility
- Use shared components in Dashboard and Comparison

src/App.css

@@ -72,6 +72,78 @@ body {
   font-size: 0.875rem;
 }
 
+.error-container button:hover {
+  background: var(--text-secondary);
+}
+
+/* Empty State */
+.empty-state {
+  display: flex;
+  flex-direction: column;
+  align-items: center;
+  justify-content: center;
+  padding: 48px 24px;
+  text-align: center;
+  color: var(--text-secondary);
+}
+
+.empty-state-icon {
+  font-size: 3rem;
+  margin-bottom: 16px;
+  opacity: 0.5;
+}
+
+.empty-state-title {
+  font-size: 1.125rem;
+  font-weight: 600;
+  color: var(--text-primary);
+  margin-bottom: 8px;
+}
+
+.empty-state-message {
+  font-size: 0.875rem;
+  color: var(--text-muted);
+  max-width: 300px;
+  margin-bottom: 20px;
+}
+
+.empty-state-action {
+  padding: 10px 20px;
+  background: var(--primary);
+  color: white;
+  border: none;
+  border-radius: 8px;
+  font-weight: 500;
+  font-size: 0.875rem;
+  cursor: pointer;
+  transition: all 0.2s;
+}
+
+.empty-state-action:hover {
+  background: #1d4ed8;
+}
+
+/* Skeleton Loader */
+.skeleton {
+  background: linear-gradient(90deg, var(--border) 25%, var(--bg) 50%, var(--border) 75%);
+  background-size: 200% 100%;
+  animation: skeleton-loading 1.5s infinite;
+  border-radius: 4px;
+}
+
+@keyframes skeleton-loading {
+  0% { background-position: 200% 0; }
+  100% { background-position: -200% 0; }
+}
+
+.skeleton-text {
+  height: 1em;
+  margin-bottom: 0.5em;
+}
+
+.skeleton-text.lg { height: 2em; width: 60%; }
+.skeleton-text.sm { height: 0.75em; width: 40%; }
+
 /* Navigation */
 .nav-bar {
   background: var(--surface);
@@ -280,6 +352,25 @@ body {
   margin-bottom: 20px;
 }
 
+.chart-card-header {
+  display: flex;
+  justify-content: space-between;
+  align-items: center;
+  margin-bottom: 16px;
+  gap: 12px;
+  flex-wrap: wrap;
+}
+
+.chart-card-header h2 {
+  margin: 0;
+}
+
+.chart-card-actions {
+  display: flex;
+  gap: 8px;
+  align-items: center;
+}
+
 .chart-container {
   height: 280px;
   position: relative;
@@ -349,6 +440,12 @@ table tbody tr:hover {
   margin: 0;
 }
 
+.controls-header-actions {
+  display: flex;
+  align-items: center;
+  gap: 8px;
+}
+
 .controls h3 {
   font-size: 0.75rem;
   font-weight: 500;
@@ -357,6 +454,23 @@ table tbody tr:hover {
   letter-spacing: 0.05em;
 }
 
+.controls-reset {
+  background: transparent;
+  border: 1px solid var(--border);
+  color: var(--text-muted);
+  padding: 4px 12px;
+  border-radius: 6px;
+  font-size: 0.75rem;
+  font-weight: 500;
+  cursor: pointer;
+  transition: all 0.2s;
+}
+
+.controls-reset:hover {
+  border-color: var(--danger);
+  color: var(--danger);
+}
+
 .controls-toggle {
   display: none;
   background: none;
@@ -661,6 +775,16 @@ table tbody tr:hover {
 }
 
 /* Carousel - elegant card slider */
+.carousel {
+  outline: none;
+}
+
+.carousel:focus-visible {
+  outline: 2px solid var(--primary);
+  outline-offset: 4px;
+  border-radius: 8px;
+}
+
 .carousel-container {
   position: relative;
   margin: 0 -6px;

src/components/Comparison.js

@@ -1,22 +1,10 @@
 import React, { useState, useMemo, useCallback, useRef } from 'react';
 import { Line, Bar } from 'react-chartjs-2';
-import {
-  Chart as ChartJS,
-  CategoryScale,
-  LinearScale,
-  PointElement,
-  LineElement,
-  BarElement,
-  Title,
-  Tooltip,
-  Legend,
-  Filler
-} from 'chart.js';
-import ChartDataLabels from 'chartjs-plugin-datalabels';
+import { EmptyState, FilterControls } from './shared';
+import { chartColors, createBaseOptions } from '../config/chartConfig';
 import {
   filterDataByDateRange,
   calculateMetrics,
-  formatCurrency,
   formatCompact,
   formatCompactCurrency,
   umrahData,
@@ -26,17 +14,6 @@ import {
   getLatestYear
 } from '../services/dataService';
 
-ChartJS.register(
-  CategoryScale, LinearScale, PointElement, LineElement,
-  BarElement, Title, Tooltip, Legend, Filler, ChartDataLabels
-);
-
-const chartColors = {
-  primary: '#2563eb',
-  muted: '#94a3b8',
-  grid: '#f1f5f9'
-};
-
 // Generate preset dates for a given year
 const generatePresetDates = (year) => ({
   'jan': { start: `${year}-01-01`, end: `${year}-01-31` },
@@ -70,7 +47,6 @@ function Comparison({ data, showDataLabels }) {
   const [filters, setFilters] = useState({ district: 'all', museum: 'all' });
   const [chartMetric, setChartMetric] = useState('revenue');
   const [chartGranularity, setChartGranularity] = useState('week');
-  const [controlsExpanded, setControlsExpanded] = useState(true);
   const [activeChart, setActiveChart] = useState(0);
   const [activeCard, setActiveCard] = useState(0);
   
@@ -159,6 +135,9 @@ function Comparison({ data, showDataLabels }) {
 
   const prevMetrics = useMemo(() => calculateMetrics(prevData), [prevData]);
   const currMetrics = useMemo(() => calculateMetrics(currData), [currData]);
+  
+  const hasData = prevData.length > 0 || currData.length > 0;
+  const resetFilters = () => setFilters({ district: 'all', museum: 'all' });
 
   const calcChange = (prev, curr) => prev === 0 ? (curr > 0 ? Infinity : 0) : ((curr - prev) / prev * 100);
 
@@ -204,31 +183,29 @@ function Comparison({ data, showDataLabels }) {
   const captureRates = quarterData?.captureRate || null;
   const pilgrimCounts = quarterData?.pilgrims || null;
 
-  const changes = {
-    revenue: calcChange(prevMetrics.revenue, currMetrics.revenue),
-    visitors: calcChange(prevMetrics.visitors, currMetrics.visitors),
-    tickets: calcChange(prevMetrics.tickets, currMetrics.tickets),
-    avgRev: calcChange(prevMetrics.avgRevPerVisitor, currMetrics.avgRevPerVisitor),
-    pilgrims: pilgrimCounts ? calcChange(pilgrimCounts.prev || 0, pilgrimCounts.curr || 0) : null,
-    captureRate: captureRates ? calcChange(captureRates.prev || 0, captureRates.curr || 0) : null
-  };
-
   // Build cards array dynamically
   const metricCards = useMemo(() => {
+    const revenueChange = calcChange(prevMetrics.revenue, currMetrics.revenue);
+    const visitorsChange = calcChange(prevMetrics.visitors, currMetrics.visitors);
+    const ticketsChange = calcChange(prevMetrics.tickets, currMetrics.tickets);
+    const avgRevChange = calcChange(prevMetrics.avgRevPerVisitor, currMetrics.avgRevPerVisitor);
+    const pilgrimsChange = pilgrimCounts ? calcChange(pilgrimCounts.prev || 0, pilgrimCounts.curr || 0) : null;
+    const captureRateChange = captureRates ? calcChange(captureRates.prev || 0, captureRates.curr || 0) : null;
+
     const cards = [
-      { title: 'Revenue', prev: prevMetrics.revenue, curr: currMetrics.revenue, change: changes.revenue, isCurrency: true },
-      { title: 'Visitors', prev: prevMetrics.visitors, curr: currMetrics.visitors, change: changes.visitors },
-      { title: 'Tickets', prev: prevMetrics.tickets, curr: currMetrics.tickets, change: changes.tickets },
-      { title: 'Avg Rev/Visitor', prev: prevMetrics.avgRevPerVisitor, curr: currMetrics.avgRevPerVisitor, change: changes.avgRev, isCurrency: true }
+      { title: 'Revenue', prev: prevMetrics.revenue, curr: currMetrics.revenue, change: revenueChange, isCurrency: true },
+      { title: 'Visitors', prev: prevMetrics.visitors, curr: currMetrics.visitors, change: visitorsChange },
+      { title: 'Tickets', prev: prevMetrics.tickets, curr: currMetrics.tickets, change: ticketsChange },
+      { title: 'Avg Rev/Visitor', prev: prevMetrics.avgRevPerVisitor, curr: currMetrics.avgRevPerVisitor, change: avgRevChange, isCurrency: true }
     ];
     if (pilgrimCounts) {
-      cards.push({ title: 'Pilgrims', prev: pilgrimCounts.prev, curr: pilgrimCounts.curr, change: changes.pilgrims, pendingMessage: 'Data not published yet' });
+      cards.push({ title: 'Pilgrims', prev: pilgrimCounts.prev, curr: pilgrimCounts.curr, change: pilgrimsChange, pendingMessage: 'Data not published yet' });
     }
     if (captureRates) {
-      cards.push({ title: 'Capture Rate', prev: captureRates.prev, curr: captureRates.curr, change: changes.captureRate, isPercent: true, pendingMessage: 'Data not published yet' });
+      cards.push({ title: 'Capture Rate', prev: captureRates.prev, curr: captureRates.curr, change: captureRateChange, isPercent: true, pendingMessage: 'Data not published yet' });
     }
     return cards;
-  }, [prevMetrics, currMetrics, changes, pilgrimCounts, captureRates]);
+  }, [prevMetrics, currMetrics, pilgrimCounts, captureRates]);
 
   const handleCardTouchStart = (e) => {
     touchStartCard.current = e.touches[0].clientX;
@@ -345,34 +322,12 @@ function Comparison({ data, showDataLabels }) {
     };
   }, [data, prevData, currData, ranges, chartMetric, getMetricValue]);
 
+  const baseOptions = useMemo(() => createBaseOptions(showDataLabels), [showDataLabels]);
   const chartOptions = {
-    responsive: true,
-    maintainAspectRatio: false,
+    ...baseOptions,
     plugins: {
-      legend: { position: 'top', align: 'end', labels: { boxWidth: 12, padding: 12, font: { size: 11 } } },
-      tooltip: { backgroundColor: '#1e293b', padding: 12, cornerRadius: 8 },
-      datalabels: {
-        display: showDataLabels,
-        color: '#1e293b',
-        font: { size: 10, weight: 600 },
-        anchor: 'end',
-        align: 'end',
-        offset: 4,
-        padding: 4,
-        backgroundColor: 'rgba(255, 255, 255, 0.85)',
-        borderRadius: 3,
-        formatter: (value) => {
-          if (value == null) return '';
-          if (value >= 1000000) return (value / 1000000).toFixed(2) + 'M';
-          if (value >= 1000) return (value / 1000).toFixed(2) + 'K';
-          if (value < 100 && value > 0) return value.toFixed(2);
-          return Math.round(value).toLocaleString();
-        }
-      }
-    },
-    scales: {
-      x: { grid: { display: false }, ticks: { font: { size: 10 }, color: '#94a3b8' } },
-      y: { grid: { color: chartColors.grid }, ticks: { font: { size: 10 }, color: '#94a3b8' }, border: { display: false } }
+      ...baseOptions.plugins,
+      legend: { position: 'top', align: 'end', labels: { boxWidth: 12, padding: 12, font: { size: 11 } } }
     }
   };
 
@@ -383,17 +338,9 @@ function Comparison({ data, showDataLabels }) {
         <p>Year-over-year analysis — same period, different years</p>
       </div>
 
-      <div className={`controls ${controlsExpanded ? 'expanded' : 'collapsed'}`}>
-        <div className="controls-header" onClick={() => setControlsExpanded(!controlsExpanded)}>
-          <h3>Select Period</h3>
-          <button className="controls-toggle">
-            {controlsExpanded ? '▲ Hide' : '▼ Show'}
-          </button>
-        </div>
-        <div className="controls-body">
-        <div className="control-row">
-          <div className="control-group">
-            <label>Preset</label>
+      <FilterControls title="Select Period" onReset={resetFilters}>
+        <FilterControls.Row>
+          <FilterControls.Group label="Preset">
             <select value={preset} onChange={e => handlePresetChange(e.target.value)}>
               <option value="custom">Custom</option>
               <option value="jan">January</option>
@@ -416,38 +363,30 @@ function Comparison({ data, showDataLabels }) {
               <option value="h2">H2</option>
               <option value="full">Full Year</option>
             </select>
-          </div>
+          </FilterControls.Group>
           {preset === 'custom' && (
             <>
-              <div className="control-group">
-                <label>From</label>
+              <FilterControls.Group label="From">
                 <input type="date" value={startDate} onChange={e => setStartDate(e.target.value)} />
-              </div>
-              <div className="control-group">
-                <label>To</label>
+              </FilterControls.Group>
+              <FilterControls.Group label="To">
                 <input type="date" value={endDate} onChange={e => setEndDate(e.target.value)} />
-              </div>
+              </FilterControls.Group>
             </>
           )}
-          <div className="control-group">
-            <label>District</label>
+          <FilterControls.Group label="District">
             <select value={filters.district} onChange={e => setFilters({...filters, district: e.target.value, museum: 'all'})}>
               <option value="all">All Districts</option>
-              {districts.map(d => (
-                <option key={d} value={d}>{d}</option>
-              ))}
+              {districts.map(d => <option key={d} value={d}>{d}</option>)}
             </select>
-          </div>
-          <div className="control-group">
-            <label>Museum</label>
+          </FilterControls.Group>
+          <FilterControls.Group label="Museum">
             <select value={filters.museum} onChange={e => setFilters({...filters, museum: e.target.value})}>
               <option value="all">All Museums</option>
-              {availableMuseums.map(m => (
-                <option key={m} value={m}>{m}</option>
-              ))}
+              {availableMuseums.map(m => <option key={m} value={m}>{m}</option>)}
             </select>
-          </div>
-        </div>
+          </FilterControls.Group>
+        </FilterControls.Row>
         <div className="period-display">
           <div className="period-box">
             <div className="label">{ranges.prev.start.substring(0, 4)}</div>
@@ -458,9 +397,18 @@ function Comparison({ data, showDataLabels }) {
             <div className="dates">{formatDate(ranges.curr.start)} → {formatDate(ranges.curr.end)}</div>
           </div>
         </div>
-        </div>
-      </div>
+      </FilterControls>
 
+      {!hasData ? (
+        <EmptyState 
+          icon="📈"
+          title="No data for this period"
+          message="No records found for the selected date range and filters."
+          action={resetFilters}
+          actionLabel="Reset Filters"
+        />
+      ) : (
+      <>
       {/* Desktop: Grid layout */}
       <div className="comparison-grid desktop-only">
         {metricCards.map((card, i) => (
@@ -661,6 +609,8 @@ function Comparison({ data, showDataLabels }) {
           ))}
         </div>
       </div>
+      </>
+      )}
     </div>
   );
 }

src/components/Dashboard.js

@@ -1,19 +1,7 @@
-import React, { useState, useMemo, useRef } from 'react';
+import React, { useState, useMemo } from 'react';
 import { Line, Doughnut, Bar } from 'react-chartjs-2';
-import {
-  Chart as ChartJS,
-  CategoryScale,
-  LinearScale,
-  PointElement,
-  LineElement,
-  BarElement,
-  ArcElement,
-  Title,
-  Tooltip,
-  Legend,
-  Filler
-} from 'chart.js';
-import ChartDataLabels from 'chartjs-plugin-datalabels';
+import { Carousel, EmptyState, FilterControls, StatCard } from './shared';
+import { chartColors, createBaseOptions } from '../config/chartConfig';
 import {
   filterData,
   calculateMetrics,
@@ -29,38 +17,24 @@ import {
   getMuseumsForDistrict
 } from '../services/dataService';
 
-ChartJS.register(
-  CategoryScale, LinearScale, PointElement, LineElement,
-  BarElement, ArcElement, Title, Tooltip, Legend, Filler,
-  ChartDataLabels
-);
-
-const chartColors = {
-  primary: '#2563eb',
-  secondary: '#7c3aed',
-  tertiary: '#0891b2',
-  muted: '#cbd5e1',
-  grid: '#f1f5f9'
+const defaultFilters = {
+  year: 'all',
+  district: 'all',
+  museum: 'all',
+  quarter: 'all'
 };
 
 function Dashboard({ data, showDataLabels }) {
-  const [filters, setFilters] = useState({
-    year: 'all',
-    district: 'all',
-    museum: 'all',
-    quarter: 'all'
-  });
-  const [filtersExpanded, setFiltersExpanded] = useState(true);
+  const [filters, setFilters] = useState(defaultFilters);
   const [activeStatCard, setActiveStatCard] = useState(0);
   const [activeChart, setActiveChart] = useState(0);
   const [trendGranularity, setTrendGranularity] = useState('week');
 
-  // Touch handlers for carousels
-  const touchStartStat = useRef(null);
-  const touchStartChart = useRef(null);
-
   const filteredData = useMemo(() => filterData(data, filters), [data, filters]);
   const metrics = useMemo(() => calculateMetrics(filteredData), [filteredData]);
+  const hasData = filteredData.length > 0;
+
+  const resetFilters = () => setFilters(defaultFilters);
 
   // Stat cards for carousel
   const statCards = useMemo(() => [
@@ -70,38 +44,11 @@ function Dashboard({ data, showDataLabels }) {
     { title: 'Avg Rev/Visitor', value: formatCurrency(metrics.avgRevPerVisitor) }
   ], [metrics]);
 
-  const handleStatTouchStart = (e) => { touchStartStat.current = e.touches[0].clientX; };
-  const handleStatTouchEnd = (e) => {
-    if (!touchStartStat.current) return;
-    const diff = touchStartStat.current - e.changedTouches[0].clientX;
-    if (Math.abs(diff) > 50) {
-      if (diff > 0 && activeStatCard < statCards.length - 1) setActiveStatCard(activeStatCard + 1);
-      else if (diff < 0 && activeStatCard > 0) setActiveStatCard(activeStatCard - 1);
-    }
-    touchStartStat.current = null;
-  };
-
-  // Chart carousel - define charts array
-  const dashboardCharts = useMemo(() => [
-    { id: 'revenue-trend', label: 'Revenue Trend' },
-    { id: 'visitors-museum', label: 'Visitors' },
-    { id: 'revenue-museum', label: 'Revenue' },
-    { id: 'quarterly-yoy', label: 'Quarterly' },
-    { id: 'district', label: 'District' },
-    { id: 'capture-rate', label: 'Capture Rate' }
-  ], []);
-
-  const handleChartTouchStart = (e) => { touchStartChart.current = e.touches[0].clientX; };
-  const handleChartTouchEnd = (e) => {
-    if (!touchStartChart.current) return;
-    const diff = touchStartChart.current - e.changedTouches[0].clientX;
-    const maxCharts = filters.museum === 'all' ? dashboardCharts.length : dashboardCharts.length - 2;
-    if (Math.abs(diff) > 50) {
-      if (diff > 0 && activeChart < maxCharts - 1) setActiveChart(activeChart + 1);
-      else if (diff < 0 && activeChart > 0) setActiveChart(activeChart - 1);
-    }
-    touchStartChart.current = null;
-  };
+  // Chart carousel labels
+  const chartLabels = useMemo(() => {
+    const labels = ['Revenue Trend', 'Visitors', 'Revenue', 'Quarterly', 'District', 'Capture Rate'];
+    return filters.museum === 'all' ? labels : labels.filter((_, i) => i !== 1 && i !== 2);
+  }, [filters.museum]);
 
   // Dynamic lists from data
   const years = useMemo(() => getUniqueYears(data), [data]);
@@ -306,7 +253,7 @@ function Dashboard({ data, showDataLabels }) {
         }
       ]
     };
-  }, [data, filters.district, filters.museum]);
+  }, [data, filters.district, filters.museum, showDataLabels]);
 
   // Quarterly table
   const quarterlyTable = useMemo(() => {
@@ -335,38 +282,7 @@ function Dashboard({ data, showDataLabels }) {
     });
   }, [data, filters.district, filters.museum]);
 
-  const dataLabelDefaults = {
-    display: showDataLabels,
-    color: '#1e293b',
-    font: { size: 10, weight: 600 },
-    anchor: 'end',
-    align: 'end',
-    offset: 4,
-    padding: 4,
-    backgroundColor: 'rgba(255, 255, 255, 0.85)',
-    borderRadius: 3,
-    formatter: (value) => {
-      if (value == null) return '';
-      if (value >= 1000000) return (value / 1000000).toFixed(2) + 'M';
-      if (value >= 1000) return (value / 1000).toFixed(2) + 'K';
-      if (value < 100 && value > 0) return value.toFixed(2);
-      return Math.round(value).toLocaleString();
-    }
-  };
-
-  const baseOptions = {
-    responsive: true,
-    maintainAspectRatio: false,
-    plugins: {
-      legend: { display: false },
-      tooltip: { backgroundColor: '#1e293b', padding: 12, cornerRadius: 8, titleFont: { size: 12 }, bodyFont: { size: 11 } },
-      datalabels: dataLabelDefaults
-    },
-    scales: {
-      x: { grid: { display: false }, ticks: { font: { size: 10 }, color: '#94a3b8' } },
-      y: { grid: { color: chartColors.grid }, ticks: { font: { size: 10 }, color: '#94a3b8' }, border: { display: false } }
-    }
-  };
+  const baseOptions = useMemo(() => createBaseOptions(showDataLabels), [showDataLabels]);
 
   return (
     <div className="dashboard">
@@ -375,114 +291,74 @@ function Dashboard({ data, showDataLabels }) {
         <p>Real-time museum analytics from Google Sheets</p>
       </div>
 
-      <div className={`controls ${filtersExpanded ? 'expanded' : 'collapsed'}`}>
-        <div className="controls-header" onClick={() => setFiltersExpanded(!filtersExpanded)}>
-          <h3>Filters</h3>
-          <button className="controls-toggle">{filtersExpanded ? '▲ Hide' : '▼ Show'}</button>
-        </div>
-        <div className="controls-body">
-          <div className="control-row">
-            <div className="control-group">
-              <label>Year</label>
-              <select value={filters.year} onChange={e => setFilters({...filters, year: e.target.value})}>
-                <option value="all">All Years</option>
-                {years.map(y => (
-                  <option key={y} value={y}>{y}</option>
-                ))}
-              </select>
-            </div>
-            <div className="control-group">
-              <label>District</label>
-              <select value={filters.district} onChange={e => setFilters({...filters, district: e.target.value, museum: 'all'})}>
-                <option value="all">All Districts</option>
-                {districts.map(d => (
-                  <option key={d} value={d}>{d}</option>
-                ))}
-              </select>
-            </div>
-            <div className="control-group">
-              <label>Museum</label>
-              <select value={filters.museum} onChange={e => setFilters({...filters, museum: e.target.value})}>
-                <option value="all">All Museums</option>
-                {availableMuseums.map(m => (
-                  <option key={m} value={m}>{m}</option>
-                ))}
-              </select>
-            </div>
-            <div className="control-group">
-              <label>Quarter</label>
-              <select value={filters.quarter} onChange={e => setFilters({...filters, quarter: e.target.value})}>
-                <option value="all">All Quarters</option>
-                <option value="1">Q1</option>
-                <option value="2">Q2</option>
-                <option value="3">Q3</option>
-                <option value="4">Q4</option>
-              </select>
-            </div>
-          </div>
-        </div>
-      </div>
+      <FilterControls title="Filters" onReset={resetFilters}>
+        <FilterControls.Row>
+          <FilterControls.Group label="Year">
+            <select value={filters.year} onChange={e => setFilters({...filters, year: e.target.value})}>
+              <option value="all">All Years</option>
+              {years.map(y => <option key={y} value={y}>{y}</option>)}
+            </select>
+          </FilterControls.Group>
+          <FilterControls.Group label="District">
+            <select value={filters.district} onChange={e => setFilters({...filters, district: e.target.value, museum: 'all'})}>
+              <option value="all">All Districts</option>
+              {districts.map(d => <option key={d} value={d}>{d}</option>)}
+            </select>
+          </FilterControls.Group>
+          <FilterControls.Group label="Museum">
+            <select value={filters.museum} onChange={e => setFilters({...filters, museum: e.target.value})}>
+              <option value="all">All Museums</option>
+              {availableMuseums.map(m => <option key={m} value={m}>{m}</option>)}
+            </select>
+          </FilterControls.Group>
+          <FilterControls.Group label="Quarter">
+            <select value={filters.quarter} onChange={e => setFilters({...filters, quarter: e.target.value})}>
+              <option value="all">All Quarters</option>
+              <option value="1">Q1</option>
+              <option value="2">Q2</option>
+              <option value="3">Q3</option>
+              <option value="4">Q4</option>
+            </select>
+          </FilterControls.Group>
+        </FilterControls.Row>
+      </FilterControls>
 
       {/* Desktop: Grid */}
       <div className="stats-grid desktop-only">
-        <div className="stat-card">
-          <h3>Total Revenue</h3>
-          <div className="stat-value">{formatCurrency(metrics.revenue)}</div>
-          {yoyChange !== null && (
-            <div className={`stat-change ${yoyChange >= 0 ? 'positive' : 'negative'}`}>
-              {yoyChange >= 0 ? '↑' : '↓'} {Math.abs(yoyChange).toFixed(1)}% YoY
-            </div>
-          )}
-        </div>
-        <div className="stat-card">
-          <h3>Total Visitors</h3>
-          <div className="stat-value">{formatNumber(metrics.visitors)}</div>
-        </div>
-        <div className="stat-card">
-          <h3>Total Tickets</h3>
-          <div className="stat-value">{formatNumber(metrics.tickets)}</div>
-        </div>
-        <div className="stat-card">
-          <h3>Avg Revenue/Visitor</h3>
-          <div className="stat-value">{formatCurrency(metrics.avgRevPerVisitor)}</div>
-        </div>
+        <StatCard title="Total Revenue" value={formatCurrency(metrics.revenue)} change={yoyChange} />
+        <StatCard title="Total Visitors" value={formatNumber(metrics.visitors)} />
+        <StatCard title="Total Tickets" value={formatNumber(metrics.tickets)} />
+        <StatCard title="Avg Revenue/Visitor" value={formatCurrency(metrics.avgRevPerVisitor)} />
       </div>
 
       {/* Mobile: Stats Carousel */}
       <div className="stats-carousel mobile-only">
-        <div className="carousel-container">
-          <div className="carousel-viewport">
-            <div 
-              className="carousel-track"
-              style={{ transform: `translateX(-${activeStatCard * 100}%)` }}
-              onTouchStart={handleStatTouchStart}
-              onTouchEnd={handleStatTouchEnd}
-            >
-              {statCards.map((card, i) => (
-                <div className="carousel-slide" key={i}>
-                  <div className="stat-card">
-                    <h3>{card.title}</h3>
-                    <div className="stat-value">{card.value}</div>
-                    {card.hasYoy && yoyChange !== null && (
-                      <div className={`stat-change ${yoyChange >= 0 ? 'positive' : 'negative'}`}>
-                        {yoyChange >= 0 ? '↑' : '↓'} {Math.abs(yoyChange).toFixed(1)}% YoY
-                      </div>
-                    )}
-                  </div>
-                </div>
-              ))}
-            </div>
-          </div>
-        </div>
-        <div className="carousel-dots labeled">
+        <Carousel 
+          activeIndex={activeStatCard} 
+          setActiveIndex={setActiveStatCard}
+          labels={statCards.map(c => c.title.replace('Total ', '').replace('Avg ', ''))}
+        >
           {statCards.map((card, i) => (
-            <button key={i} className={`carousel-dot ${activeStatCard === i ? 'active' : ''}`} onClick={() => setActiveStatCard(i)}>
-              <span className="dot-label">{card.title.replace('Total ', '').replace('Avg ', '')}</span>
-            </button>
+            <StatCard 
+              key={i}
+              title={card.title} 
+              value={card.value} 
+              change={card.hasYoy ? yoyChange : null}
+            />
           ))}
-        </div>
+        </Carousel>
       </div>
 
+      {!hasData ? (
+        <EmptyState 
+          icon="📊"
+          title="No data found"
+          message="No records match your current filters. Try adjusting your selection."
+          action={resetFilters}
+          actionLabel="Reset Filters"
+        />
+      ) : (
+      <>
       <div className="chart-card full-width" style={{marginBottom: '16px'}}>
         <h2>Quarterly Comparison: 2024 vs 2025</h2>
         <div className="table-container">
@@ -619,8 +495,6 @@ function Dashboard({ data, showDataLabels }) {
             <div 
               className="carousel-track"
               style={{ transform: `translateX(-${activeChart * 100}%)` }}
-              onTouchStart={handleChartTouchStart}
-              onTouchEnd={handleChartTouchEnd}
             >
               <div className="carousel-slide">
                 <div className="chart-card">
@@ -722,17 +596,19 @@ function Dashboard({ data, showDataLabels }) {
         </div>
 
         <div className="carousel-dots">
-          {(filters.museum === 'all' ? dashboardCharts : dashboardCharts.filter(c => !['visitors-museum', 'revenue-museum'].includes(c.id))).map((chart, i) => (
+          {chartLabels.map((label, i) => (
             <button
-              key={chart.id}
+              key={label}
               className={`carousel-dot ${activeChart === i ? 'active' : ''}`}
               onClick={() => setActiveChart(i)}
             >
-              <span className="dot-label">{chart.label}</span>
+              <span className="dot-label">{label}</span>
             </button>
           ))}
         </div>
       </div>
+      </>
+      )}
     </div>
   );
 }

src/components/shared/Carousel.jsx

@@ -0,0 +1,78 @@
+import React, { useRef, useCallback } from 'react';
+
+function Carousel({ 
+  children, 
+  activeIndex, 
+  setActiveIndex, 
+  labels = [],
+  showLabels = true,
+  className = ''
+}) {
+  const touchStart = useRef(null);
+  const itemCount = React.Children.count(children);
+
+  const handleTouchStart = useCallback((e) => {
+    touchStart.current = e.touches[0].clientX;
+  }, []);
+
+  const handleTouchEnd = useCallback((e) => {
+    if (!touchStart.current) return;
+    const diff = touchStart.current - e.changedTouches[0].clientX;
+    if (Math.abs(diff) > 50) {
+      if (diff > 0 && activeIndex < itemCount - 1) {
+        setActiveIndex(activeIndex + 1);
+      } else if (diff < 0 && activeIndex > 0) {
+        setActiveIndex(activeIndex - 1);
+      }
+    }
+    touchStart.current = null;
+  }, [activeIndex, setActiveIndex, itemCount]);
+
+  const handleKeyDown = useCallback((e) => {
+    if (e.key === 'ArrowLeft' && activeIndex > 0) {
+      setActiveIndex(activeIndex - 1);
+    } else if (e.key === 'ArrowRight' && activeIndex < itemCount - 1) {
+      setActiveIndex(activeIndex + 1);
+    }
+  }, [activeIndex, setActiveIndex, itemCount]);
+
+  return (
+    <div className={`carousel ${className}`} onKeyDown={handleKeyDown} tabIndex={0}>
+      <div className="carousel-container">
+        <div className="carousel-viewport">
+          <div 
+            className="carousel-track"
+            style={{ transform: `translateX(-${activeIndex * 100}%)` }}
+            onTouchStart={handleTouchStart}
+            onTouchEnd={handleTouchEnd}
+          >
+            {React.Children.map(children, (child, i) => (
+              <div className="carousel-slide" key={i}>
+                {child}
+              </div>
+            ))}
+          </div>
+        </div>
+      </div>
+      
+      <div className={`carousel-dots ${showLabels ? 'labeled' : ''}`} role="tablist">
+        {Array.from({ length: itemCount }).map((_, i) => (
+          <button
+            key={i}
+            className={`carousel-dot ${activeIndex === i ? 'active' : ''}`}
+            onClick={() => setActiveIndex(i)}
+            role="tab"
+            aria-selected={activeIndex === i}
+            aria-label={labels[i] || `Slide ${i + 1}`}
+          >
+            {showLabels && labels[i] && (
+              <span className="dot-label">{labels[i]}</span>
+            )}
+          </button>
+        ))}
+      </div>
+    </div>
+  );
+}
+
+export default Carousel;

src/components/shared/ChartCard.jsx

@@ -0,0 +1,28 @@
+import React from 'react';
+
+function ChartCard({ 
+  title, 
+  children, 
+  className = '',
+  headerRight = null,
+  fullWidth = false,
+  halfWidth = false
+}) {
+  const sizeClass = fullWidth ? 'full-width' : halfWidth ? 'half-width' : '';
+  
+  return (
+    <div className={`chart-card ${sizeClass} ${className}`}>
+      {(title || headerRight) && (
+        <div className="chart-card-header">
+          {title && <h2>{title}</h2>}
+          {headerRight && <div className="chart-card-actions">{headerRight}</div>}
+        </div>
+      )}
+      <div className="chart-container">
+        {children}
+      </div>
+    </div>
+  );
+}
+
+export default ChartCard;

src/components/shared/EmptyState.jsx

@@ -0,0 +1,24 @@
+import React from 'react';
+
+function EmptyState({ 
+  icon = '📊', 
+  title = 'No data found', 
+  message = 'Try adjusting your filters',
+  action,
+  actionLabel = 'Reset Filters'
+}) {
+  return (
+    <div className="empty-state">
+      <div className="empty-state-icon">{icon}</div>
+      <h3 className="empty-state-title">{title}</h3>
+      <p className="empty-state-message">{message}</p>
+      {action && (
+        <button className="empty-state-action" onClick={action}>
+          {actionLabel}
+        </button>
+      )}
+    </div>
+  );
+}
+
+export default EmptyState;

src/components/shared/FilterControls.jsx

@@ -0,0 +1,53 @@
+import React, { useState } from 'react';
+
+function FilterControls({ 
+  children, 
+  title = 'Filters',
+  defaultExpanded = true,
+  onReset = null,
+  className = ''
+}) {
+  const [expanded, setExpanded] = useState(defaultExpanded);
+
+  return (
+    <div className={`controls ${expanded ? 'expanded' : 'collapsed'} ${className}`}>
+      <div className="controls-header" onClick={() => setExpanded(!expanded)}>
+        <h3>{title}</h3>
+        <div className="controls-header-actions">
+          {onReset && expanded && (
+            <button 
+              className="controls-reset"
+              onClick={(e) => { e.stopPropagation(); onReset(); }}
+            >
+              Reset
+            </button>
+          )}
+          <button className="controls-toggle">
+            {expanded ? '▲ Hide' : '▼ Show'}
+          </button>
+        </div>
+      </div>
+      <div className="controls-body">
+        {children}
+      </div>
+    </div>
+  );
+}
+
+function FilterGroup({ label, children }) {
+  return (
+    <div className="control-group">
+      <label>{label}</label>
+      {children}
+    </div>
+  );
+}
+
+function FilterRow({ children }) {
+  return <div className="control-row">{children}</div>;
+}
+
+FilterControls.Group = FilterGroup;
+FilterControls.Row = FilterRow;
+
+export default FilterControls;

src/components/shared/StatCard.jsx

@@ -0,0 +1,19 @@
+import React from 'react';
+
+function StatCard({ title, value, change = null, changeLabel = 'YoY' }) {
+  const isPositive = change !== null && change >= 0;
+  
+  return (
+    <div className="stat-card">
+      <h3>{title}</h3>
+      <div className="stat-value">{value}</div>
+      {change !== null && (
+        <div className={`stat-change ${isPositive ? 'positive' : 'negative'}`}>
+          {isPositive ? '↑' : '↓'} {Math.abs(change).toFixed(1)}% {changeLabel}
+        </div>
+      )}
+    </div>
+  );
+}
+
+export default StatCard;

src/components/shared/ToggleSwitch.jsx

@@ -0,0 +1,21 @@
+import React from 'react';
+
+function ToggleSwitch({ options, value, onChange, className = '' }) {
+  return (
+    <div className={`toggle-switch ${className}`} role="radiogroup">
+      {options.map((option) => (
+        <button
+          key={option.value}
+          className={value === option.value ? 'active' : ''}
+          onClick={() => onChange(option.value)}
+          role="radio"
+          aria-checked={value === option.value}
+        >
+          {option.label}
+        </button>
+      ))}
+    </div>
+  );
+}
+
+export default ToggleSwitch;

src/components/shared/index.js

@@ -0,0 +1,6 @@
+export { default as Carousel } from './Carousel';
+export { default as ChartCard } from './ChartCard';
+export { default as EmptyState } from './EmptyState';
+export { default as FilterControls } from './FilterControls';
+export { default as StatCard } from './StatCard';
+export { default as ToggleSwitch } from './ToggleSwitch';

src/config/chartConfig.js

@@ -0,0 +1,97 @@
+import {
+  Chart as ChartJS,
+  CategoryScale,
+  LinearScale,
+  PointElement,
+  LineElement,
+  BarElement,
+  ArcElement,
+  Title,
+  Tooltip,
+  Legend,
+  Filler
+} from 'chart.js';
+import ChartDataLabels from 'chartjs-plugin-datalabels';
+
+// Register ChartJS components once
+ChartJS.register(
+  CategoryScale,
+  LinearScale,
+  PointElement,
+  LineElement,
+  BarElement,
+  ArcElement,
+  Title,
+  Tooltip,
+  Legend,
+  Filler,
+  ChartDataLabels
+);
+
+export const chartColors = {
+  primary: '#2563eb',
+  secondary: '#7c3aed',
+  tertiary: '#0891b2',
+  success: '#059669',
+  danger: '#dc2626',
+  muted: '#94a3b8',
+  grid: '#f1f5f9'
+};
+
+export const createDataLabelConfig = (showDataLabels) => ({
+  display: showDataLabels,
+  color: '#1e293b',
+  font: { size: 10, weight: 600 },
+  anchor: 'end',
+  align: 'end',
+  offset: 4,
+  padding: 4,
+  backgroundColor: 'rgba(255, 255, 255, 0.85)',
+  borderRadius: 3,
+  formatter: (value) => {
+    if (value == null) return '';
+    if (value >= 1000000) return (value / 1000000).toFixed(2) + 'M';
+    if (value >= 1000) return (value / 1000).toFixed(2) + 'K';
+    if (value < 100 && value > 0) return value.toFixed(2);
+    return Math.round(value).toLocaleString();
+  }
+});
+
+export const createBaseOptions = (showDataLabels) => ({
+  responsive: true,
+  maintainAspectRatio: false,
+  plugins: {
+    legend: { display: false },
+    tooltip: { 
+      backgroundColor: '#1e293b', 
+      padding: 12, 
+      cornerRadius: 8, 
+      titleFont: { size: 12 }, 
+      bodyFont: { size: 11 } 
+    },
+    datalabels: createDataLabelConfig(showDataLabels)
+  },
+  scales: {
+    x: { 
+      grid: { display: false }, 
+      ticks: { font: { size: 10 }, color: '#94a3b8' } 
+    },
+    y: { 
+      grid: { color: chartColors.grid }, 
+      ticks: { font: { size: 10 }, color: '#94a3b8' }, 
+      border: { display: false } 
+    }
+  }
+});
+
+export const lineDatasetDefaults = {
+  borderWidth: 2,
+  tension: 0.4,
+  fill: true,
+  pointRadius: 0,
+  pointHoverRadius: 4
+};
+
+export const barDatasetDefaults = {
+  borderRadius: 4
+};

src/services/dataService.js

@@ -3,15 +3,12 @@ const SPREADSHEET_ID = '1rdK1e7jmfu-es4Ql0YwDYNBY2OvVihBjYaXTM-MHHqg';
 const SHEET_NAME = 'Consolidated Data';
 const SHEET_URL = `https://docs.google.com/spreadsheets/d/${SPREADSHEET_ID}/gviz/tq?tqx=out:csv&sheet=${encodeURIComponent(SHEET_NAME)}`;
 
-// NocoDB configuration
-// Use relative URL for dev proxy, full URL for production
-const NOCODB_URL = process.env.NODE_ENV === 'production' ? 'http://localhost:8090' : '';
-const NOCODB_TOKEN = 'By-wCdkUm6N9JdfmNpGH2jd6LqEejwOXER7FMkgr';
+// NocoDB configuration - uses environment variables for security
+// Set REACT_APP_NOCODB_URL and REACT_APP_NOCODB_TOKEN in .env.local
+const NOCODB_URL = process.env.REACT_APP_NOCODB_URL || '';
+const NOCODB_TOKEN = process.env.REACT_APP_NOCODB_TOKEN || '';
 
-// Old flat table (for backwards compatibility)
-const NOCODB_TABLE_ID = 'mzcz8ktjybcjc79';
-
-// New normalized tables (Samaya Museums Statistics base)
+// Table IDs (not sensitive - just identifiers)
 const NOCODB_TABLES = {
   districts: 'm8cup7lesbet0sa',
   museums: 'm1c7od7mdirffvu',