feat: vylepšená podpora themes

client/src/App.scss

@@ -87,42 +87,6 @@
   --luncher-shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.5), 0 4px 6px -4px rgb(0 0 0 / 0.4);
 }
 
-// Modrý motiv – světlý
-[data-luncher-color="blue"][data-bs-theme="light"] {
-  --luncher-primary: #2563eb;
-  --luncher-primary-hover: #1d4ed8;
-  --luncher-primary-light: #dbeafe;
-  --luncher-action-icon: #2563eb;
-  --luncher-success: #2563eb;
-}
-
-// Modrý motiv – tmavý
-[data-luncher-color="blue"][data-bs-theme="dark"] {
-  --luncher-primary: #3b82f6;
-  --luncher-primary-hover: #60a5fa;
-  --luncher-primary-light: #172554;
-  --luncher-action-icon: #3b82f6;
-  --luncher-success: #3b82f6;
-}
-
-// Fialový motiv – světlý
-[data-luncher-color="purple"][data-bs-theme="light"] {
-  --luncher-primary: #7c3aed;
-  --luncher-primary-hover: #6d28d9;
-  --luncher-primary-light: #ede9fe;
-  --luncher-action-icon: #7c3aed;
-  --luncher-success: #7c3aed;
-}
-
-// Fialový motiv – tmavý
-[data-luncher-color="purple"][data-bs-theme="dark"] {
-  --luncher-primary: #a78bfa;
-  --luncher-primary-hover: #c4b5fd;
-  --luncher-primary-light: #2e1065;
-  --luncher-action-icon: #a78bfa;
-  --luncher-success: #a78bfa;
-}
-
 // ============================================
 // BASE STYLES
 // ============================================
@@ -263,32 +227,6 @@ body {
     transform: rotate(15deg);
   }
 
-  // Přizpůsobení pro NavDropdown (palette ikona)
-  &.nav-item.dropdown {
-    .dropdown-toggle {
-      background: transparent;
-      border: none;
-      color: var(--luncher-navbar-text);
-      padding: 8px 12px;
-      font-size: 1.1rem;
-      display: flex;
-      align-items: center;
-
-      &::after {
-        display: none;
-      }
-
-      &:hover {
-        background: rgba(255, 255, 255, 0.1);
-        transform: scale(1.1);
-      }
-
-      &:focus {
-        outline: none;
-        box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.3);
-      }
-    }
-  }
 }
 
 // ============================================

client/src/components/Header.tsx

@@ -2,7 +2,8 @@ import { useEffect, useState } from "react";
 import { Navbar, Nav, NavDropdown, Modal, Button } from "react-bootstrap";
 import { useAuth } from "../context/auth";
 import SettingsModal from "./modals/SettingsModal";
-import { useSettings, ThemePreference, ColorTheme } from "../context/settings";
+import { useSettings, ThemePreference } from "../context/settings";
+import HuePicker from "./HuePicker";
 import FeaturesVotingModal from "./modals/FeaturesVotingModal";
 import PizzaCalculatorModal from "./modals/PizzaCalculatorModal";
 import RefreshMenuModal from "./modals/RefreshMenuModal";
@@ -13,7 +14,7 @@ import { useNavigate } from "react-router";
 import { STATS_URL, OBJEDNANI_URL } from "../AppRoutes";
 import { FeatureRequest, getVotes, updateVote, LunchChoices, getChangelogs } from "../../../types";
 import { FontAwesomeIcon } from "@fortawesome/react-fontawesome";
-import { faSun, faMoon, faPalette } from "@fortawesome/free-solid-svg-icons";
+import { faSun, faMoon } from "@fortawesome/free-solid-svg-icons";
 import { formatDateString } from "../Utils";
 
 const LAST_SEEN_CHANGELOG_KEY = "lastChangelogDate";
@@ -40,25 +41,7 @@ export default function Header({ choices, dayIndex }: Props) {
     const [clearMockModalOpen, setClearMockModalOpen] = useState<boolean>(false);
     const [featureVotes, setFeatureVotes] = useState<FeatureRequest[] | undefined>([]);
 
-    // Zjistíme aktuální efektivní téma (pro zobrazení správné ikony)
-    const [effectiveTheme, setEffectiveTheme] = useState<'light' | 'dark'>('light');
-
-    useEffect(() => {
-        const updateEffectiveTheme = () => {
-            if (settings?.themePreference === 'system') {
-                const isDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
-                setEffectiveTheme(isDark ? 'dark' : 'light');
-            } else {
-                setEffectiveTheme(settings?.themePreference || 'light');
-            }
-        };
-
-        updateEffectiveTheme();
-
-        const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
-        mediaQuery.addEventListener('change', updateEffectiveTheme);
-        return () => mediaQuery.removeEventListener('change', updateEffectiveTheme);
-    }, [settings?.themePreference]);
+    const effectiveDark = settings?.effectiveDark ?? false;
 
     useEffect(() => {
         if (auth?.login) {
@@ -110,8 +93,7 @@ export default function Header({ choices, dayIndex }: Props) {
     }
 
     const toggleTheme = () => {
-        // Přepínáme mezi light a dark (ignorujeme system pro jednoduchost)
-        const newTheme: ThemePreference = effectiveTheme === 'dark' ? 'light' : 'dark';
+        const newTheme: ThemePreference = effectiveDark ? 'light' : 'dark';
         settings?.setThemePreference(newTheme);
     }
 
@@ -195,21 +177,16 @@ export default function Header({ choices, dayIndex }: Props) {
                 <button
                     className="theme-toggle"
                     onClick={toggleTheme}
-                    title={effectiveTheme === 'dark' ? 'Přepnout na světlý režim' : 'Přepnout na tmavý režim'}
+                    title={effectiveDark ? 'Přepnout na světlý režim' : 'Přepnout na tmavý režim'}
                     aria-label="Přepnout světlý/tmavý režim"
                 >
-                    <FontAwesomeIcon icon={effectiveTheme === 'dark' ? faSun : faMoon} />
+                    <FontAwesomeIcon icon={effectiveDark ? faSun : faMoon} />
                 </button>
-                <NavDropdown
-                    align="end"
-                    title={<FontAwesomeIcon icon={faPalette} />}
-                    id="color-theme-dropdown"
-                    className="theme-toggle"
-                >
-                    <NavDropdown.Item active={settings?.colorTheme === 'green'} onClick={() => settings?.setColorTheme('green' as ColorTheme)}>🟢 Zelený</NavDropdown.Item>
-                    <NavDropdown.Item active={settings?.colorTheme === 'blue'} onClick={() => settings?.setColorTheme('blue' as ColorTheme)}>🔵 Modrý</NavDropdown.Item>
-                    <NavDropdown.Item active={settings?.colorTheme === 'purple'} onClick={() => settings?.setColorTheme('purple' as ColorTheme)}>🟣 Fialový</NavDropdown.Item>
-                </NavDropdown>
+                <HuePicker
+                    accentHue={settings?.accentHue ?? 142}
+                    isDark={effectiveDark}
+                    onChange={hue => settings?.setAccentHue(hue)}
+                />
                 <NavDropdown align="end" title={auth?.login} id="basic-nav-dropdown">
                     <NavDropdown.Item onClick={() => setSettingsModalOpen(true)}>Nastavení</NavDropdown.Item>
                     <NavDropdown.Item onClick={() => setRefreshMenuModalOpen(true)}>Přenačtení menu</NavDropdown.Item>

client/src/components/HuePicker.scss

@@ -0,0 +1,138 @@
+.hue-picker-dropdown {
+  .dropdown-toggle {
+    background: transparent !important;
+    border: none !important;
+    color: var(--luncher-navbar-text) !important;
+    padding: 8px 12px;
+    font-size: 1.1rem;
+    display: flex;
+    align-items: center;
+    cursor: pointer;
+    border-radius: var(--luncher-radius-sm);
+    transition: var(--luncher-transition);
+
+    &::after {
+      display: none;
+    }
+
+    &:hover {
+      background: rgba(255, 255, 255, 0.1) !important;
+      transform: scale(1.1);
+    }
+
+    &:focus {
+      outline: none;
+      box-shadow: 0 0 0 2px rgba(255, 255, 255, 0.3) !important;
+    }
+  }
+}
+
+.hue-picker-panel {
+  padding: 0 !important;
+  min-width: 240px;
+
+  .hue-picker-inner {
+    padding: 14px 16px;
+  }
+
+  .hue-picker-label {
+    font-size: 0.75rem;
+    font-weight: 600;
+    text-transform: uppercase;
+    letter-spacing: 0.5px;
+    color: var(--luncher-text-secondary);
+    margin-bottom: 12px;
+  }
+}
+
+.hue-slider {
+  -webkit-appearance: none;
+  appearance: none;
+  width: 100%;
+  height: 12px;
+  border-radius: 6px;
+  background: linear-gradient(
+    to right,
+    hsl(0 70% 50%), hsl(30 70% 50%), hsl(60 70% 50%), hsl(90 70% 50%),
+    hsl(120 70% 50%), hsl(150 70% 50%), hsl(180 70% 50%), hsl(210 70% 50%),
+    hsl(240 70% 50%), hsl(270 70% 50%), hsl(300 70% 50%), hsl(330 70% 50%), hsl(360 70% 50%)
+  );
+  outline: none;
+  cursor: pointer;
+  margin-bottom: 14px;
+
+  &::-webkit-slider-thumb {
+    -webkit-appearance: none;
+    appearance: none;
+    width: 20px;
+    height: 20px;
+    border-radius: 50%;
+    background: white;
+    border: 2px solid rgba(0, 0, 0, 0.25);
+    cursor: pointer;
+    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
+    transition: transform 0.15s ease;
+
+    &:hover {
+      transform: scale(1.15);
+    }
+  }
+
+  &::-moz-range-thumb {
+    width: 20px;
+    height: 20px;
+    border-radius: 50%;
+    background: white;
+    border: 2px solid rgba(0, 0, 0, 0.25);
+    cursor: pointer;
+    box-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
+  }
+}
+
+.hue-presets {
+  display: flex;
+  gap: 8px;
+  margin-bottom: 14px;
+
+  .hue-swatch {
+    width: 26px;
+    height: 26px;
+    border-radius: 50%;
+    border: 2px solid transparent;
+    cursor: pointer;
+    padding: 0;
+    transition: transform 0.15s ease, border-color 0.15s ease;
+    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
+
+    &:hover {
+      transform: scale(1.15);
+    }
+
+    &.active {
+      border-color: var(--luncher-text);
+      transform: scale(1.1);
+    }
+  }
+}
+
+.hue-preview {
+  display: flex;
+  align-items: center;
+  gap: 10px;
+  padding-top: 4px;
+  border-top: 1px solid var(--luncher-border);
+
+  .hue-preview-chip {
+    width: 32px;
+    height: 32px;
+    border-radius: var(--luncher-radius-sm);
+    flex-shrink: 0;
+    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
+    transition: background 0.2s ease;
+  }
+
+  span {
+    font-size: 0.8rem;
+    color: var(--luncher-text-secondary);
+  }
+}

client/src/components/HuePicker.tsx

@@ -0,0 +1,71 @@
+import { Dropdown } from 'react-bootstrap';
+import { FontAwesomeIcon } from '@fortawesome/react-fontawesome';
+import { faPalette } from '@fortawesome/free-solid-svg-icons';
+import './HuePicker.scss';
+
+const PRESETS = [
+  { hue: 142, label: 'Zelená' },
+  { hue: 217, label: 'Modrá' },
+  { hue: 263, label: 'Fialová' },
+  { hue: 0, label: 'Červená' },
+  { hue: 28, label: 'Oranžová' },
+  { hue: 340, label: 'Růžová' },
+];
+
+type Props = {
+  accentHue: number;
+  isDark: boolean;
+  onChange: (hue: number) => void;
+};
+
+function swatchColor(hue: number, isDark: boolean): string {
+  return `hsl(${hue} 70% ${isDark ? 55 : 38}%)`;
+}
+
+export default function HuePicker({ accentHue, isDark, onChange }: Props) {
+  return (
+    <Dropdown align="end" autoClose="outside" className="hue-picker-dropdown">
+      <Dropdown.Toggle
+        as="button"
+        className="theme-toggle"
+        aria-label="Barva zvýraznění"
+        title="Barva zvýraznění"
+      >
+        <FontAwesomeIcon icon={faPalette} />
+      </Dropdown.Toggle>
+      <Dropdown.Menu className="hue-picker-panel">
+        <div className="hue-picker-inner">
+          <div className="hue-picker-label">Barva zvýraznění</div>
+          <input
+            type="range"
+            min={0}
+            max={360}
+            value={accentHue}
+            onChange={e => onChange(parseInt(e.target.value, 10))}
+            className="hue-slider"
+            aria-label="Odstín barvy zvýraznění"
+          />
+          <div className="hue-presets">
+            {PRESETS.map(p => (
+              <button
+                key={p.hue}
+                className={`hue-swatch${accentHue === p.hue ? ' active' : ''}`}
+                style={{ background: swatchColor(p.hue, isDark) }}
+                title={p.label}
+                onClick={() => onChange(p.hue)}
+                aria-label={p.label}
+              />
+            ))}
+          </div>
+          <div className="hue-preview">
+            <div
+              className="hue-preview-chip"
+              style={{ background: swatchColor(accentHue, isDark) }}
+            />
+            <span>Aktuální barva zvýraznění</span>
+          </div>
+        </div>
+      </Dropdown.Menu>
+    </Dropdown>
+  );
+}

client/src/context/settings.tsx

@@ -4,22 +4,23 @@ const BANK_ACCOUNT_NUMBER_KEY = 'bank_account_number';
 const BANK_ACCOUNT_HOLDER_KEY = 'bank_account_holder_name';
 const HIDE_SOUPS_KEY = 'hide_soups';
 const THEME_KEY = 'theme_preference';
-const COLOR_THEME_KEY = 'color_theme';
+const ACCENT_HUE_KEY = 'accent_hue';
+const LEGACY_COLOR_THEME_KEY = 'color_theme';
 
 export type ThemePreference = 'system' | 'light' | 'dark';
-export type ColorTheme = 'green' | 'blue' | 'purple';
 
 export type SettingsContextProps = {
   bankAccount?: string,
   holderName?: string,
   hideSoups?: boolean,
   themePreference: ThemePreference,
-  colorTheme: ColorTheme,
+  accentHue: number,
+  effectiveDark: boolean,
   setBankAccountNumber: (accountNumber?: string) => void,
   setBankAccountHolderName: (holderName?: string) => void,
   setHideSoupsOption: (hideSoups?: boolean) => void,
   setThemePreference: (theme: ThemePreference) => void,
-  setColorTheme: (color: ColorTheme) => void,
+  setAccentHue: (hue: number) => void,
 }
 
 type ContextProps = {
@@ -49,16 +50,58 @@ function getInitialTheme(): ThemePreference {
   return 'system';
 }
 
-function getInitialColorTheme(): ColorTheme {
+function getInitialAccentHue(): number {
   try {
-    const saved = localStorage.getItem(COLOR_THEME_KEY) as ColorTheme | null;
-    if (saved && ['green', 'blue', 'purple'].includes(saved)) {
-      return saved;
+    const saved = localStorage.getItem(ACCENT_HUE_KEY);
+    if (saved !== null) {
+      const n = parseInt(saved, 10);
+      if (!isNaN(n) && n >= 0 && n <= 360) return n;
     }
-  } catch (e) {
+    // Migrace ze starého string formátu (green/blue/purple)
+    const old = localStorage.getItem(LEGACY_COLOR_THEME_KEY);
+    if (old === 'blue') return 217;
+    if (old === 'purple') return 263;
+  } catch {
     // localStorage nedostupný
   }
-  return 'green';
+  return 142;
+}
+
+// Převod HSL na relativní jas dle WCAG (pro výpočet kontrastu s bílým textem)
+function hslToRelativeLuminance(h: number, s: number, l: number): number {
+  const sn = s / 100, ln = l / 100;
+  const a = sn * Math.min(ln, 1 - ln);
+  const ch = (n: number) => {
+    const k = (n + h / 30) % 12;
+    return ln - a * Math.max(Math.min(k - 3, 9 - k, 1), -1);
+  };
+  const toLinear = (c: number) => c <= 0.04045 ? c / 12.92 : Math.pow((c + 0.055) / 1.055, 2.4);
+  return 0.2126 * toLinear(ch(0)) + 0.7152 * toLinear(ch(8)) + 0.0722 * toLinear(ch(4));
+}
+
+// Najde nejnižší světlost, při které má barva dostatečný kontrast s bílým textem (WCAG AA 4.5:1)
+function adjustedL(hue: number, sat: number, targetL: number): number {
+  let l = targetL;
+  while (l >= 5) {
+    const lum = hslToRelativeLuminance(hue, sat, l);
+    if (1.05 / (lum + 0.05) >= 4.5) return l;
+    l -= 1;
+  }
+  return l;
+}
+
+function applyAccentColors(hue: number, isDark: boolean): void {
+  const sat = 70;
+  const baseL = adjustedL(hue, sat, isDark ? 55 : 38);
+  const hoverL = isDark ? Math.min(baseL + 10, 80) : Math.max(baseL - 10, 10);
+  const root = document.documentElement;
+  root.style.setProperty('--luncher-primary', `hsl(${hue} ${sat}% ${baseL}%)`);
+  root.style.setProperty('--luncher-primary-hover', `hsl(${hue} ${sat}% ${hoverL}%)`);
+  root.style.setProperty('--luncher-primary-light', isDark
+    ? `hsl(${hue} 60% 12%)`
+    : `hsl(${hue} 60% 92%)`);
+  root.style.setProperty('--luncher-action-icon', `hsl(${hue} ${sat}% ${baseL}%)`);
+  root.style.setProperty('--luncher-success', `hsl(${hue} ${sat}% ${baseL}%)`);
 }
 
 function useProvideSettings(): SettingsContextProps {
@@ -66,7 +109,15 @@ function useProvideSettings(): SettingsContextProps {
   const [holderName, setHolderName] = useState<string | undefined>();
   const [hideSoups, setHideSoups] = useState<boolean | undefined>();
   const [themePreference, setTheme] = useState<ThemePreference>(getInitialTheme);
-  const [colorTheme, setColor] = useState<ColorTheme>(getInitialColorTheme);
+  const [accentHue, setHue] = useState<number>(getInitialAccentHue);
+  const [effectiveDark, setEffectiveDark] = useState<boolean>(() => {
+    try {
+      const pref = localStorage.getItem(THEME_KEY) as ThemePreference | null;
+      if (pref === 'dark') return true;
+      if (pref === 'light') return false;
+    } catch { /* noop */ }
+    return window.matchMedia?.('(prefers-color-scheme: dark)').matches ?? false;
+  });
 
   useEffect(() => {
     const accountNumber = localStorage.getItem(BANK_ACCOUNT_NUMBER_KEY);
@@ -112,29 +163,27 @@ function useProvideSettings(): SettingsContextProps {
   }, [themePreference]);
 
   useEffect(() => {
-    localStorage.setItem(COLOR_THEME_KEY, colorTheme);
-    document.documentElement.setAttribute('data-luncher-color', colorTheme);
-  }, [colorTheme]);
-
-  useEffect(() => {
-    const applyTheme = (theme: 'light' | 'dark') => {
-      document.documentElement.setAttribute('data-bs-theme', theme);
+    const applyTheme = (dark: boolean) => {
+      document.documentElement.setAttribute('data-bs-theme', dark ? 'dark' : 'light');
+      setEffectiveDark(dark);
     };
-
     if (themePreference === 'system') {
-      const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
-      applyTheme(mediaQuery.matches ? 'dark' : 'light');
-
-      const handler = (e: MediaQueryListEvent) => {
-        applyTheme(e.matches ? 'dark' : 'light');
-      };
-      mediaQuery.addEventListener('change', handler);
-      return () => mediaQuery.removeEventListener('change', handler);
+      const mq = window.matchMedia('(prefers-color-scheme: dark)');
+      applyTheme(mq.matches);
+      const handler = (e: MediaQueryListEvent) => applyTheme(e.matches);
+      mq.addEventListener('change', handler);
+      return () => mq.removeEventListener('change', handler);
     } else {
-      applyTheme(themePreference);
+      applyTheme(themePreference === 'dark');
     }
   }, [themePreference]);
 
+  // Aplikuje accent barvy při změně hue nebo přepnutí světlý/tmavý
+  useEffect(() => {
+    localStorage.setItem(ACCENT_HUE_KEY, String(accentHue));
+    applyAccentColors(accentHue, effectiveDark);
+  }, [accentHue, effectiveDark]);
+
   function setBankAccountNumber(bankAccount?: string) {
     setBankAccount(bankAccount);
   }
@@ -151,8 +200,8 @@ function useProvideSettings(): SettingsContextProps {
     setTheme(theme);
   }
 
-  function setColorTheme(color: ColorTheme) {
-    setColor(color);
+  function setAccentHue(hue: number) {
+    setHue(hue);
   }
 
   return {
@@ -160,11 +209,12 @@ function useProvideSettings(): SettingsContextProps {
     holderName,
     hideSoups,
     themePreference,
-    colorTheme,
+    accentHue,
+    effectiveDark,
     setBankAccountNumber,
     setBankAccountHolderName,
     setHideSoupsOption,
     setThemePreference,
-    setColorTheme,
+    setAccentHue,
   }
 }