/* ========================================
   BLUESTONE DESIGN SYSTEM
   Verze 1.0 - Leden 2025
   Hlavní barva: #424A5D
   ======================================== */

/* ===== CSS RESET ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* ===== CSS PROMĚNNÉ - BAREVNÁ PALETA ===== */
:root {
    /* Hlavní modrošedá paleta */
    --blue-950: #1a1d26;
    --blue-900: #2a2f3d;
    --blue-800: #353b4d;
    --blue-700: #424A5D;  /* HLAVNÍ BARVA */
    --blue-600: #525c72;
    --blue-500: #6b7689;
    --blue-400: #8892a6;
    --blue-300: #a8b1c3;
    --blue-200: #c8d0de;
    --blue-100: #e4e8f0;
    --blue-50: #f4f6f9;
    
    /* Neutrální šedé */
    --gray-900: #1f2937;
    --gray-800: #374151;
    --gray-700: #4b5563;
    --gray-600: #6b7280;
    --gray-500: #9ca3af;
    --gray-400: #d1d5db;
    --gray-300: #e5e7eb;
    --gray-200: #f3f4f6;
    --gray-100: #f9fafb;
    --white: #ffffff;
    
    /* Akcentové barvy - tlumené varianty */
    --cyan-accent: #06b6d4;      /* Komunikace */
    --indigo-accent: #6366f1;    /* Schůzky */
    --amber-accent: #f59e0b;     /* Poznámky */
    --emerald-accent: #10b981;   /* Úkoly */
    --rose-accent: #f43f5e;      /* Důležité/Nebezpečí */
    --violet-accent: #8b5cf6;    /* Speciální */
    
    /* Systémové barvy */
    --primary: var(--blue-700);
    --primary-hover: var(--blue-800);
    --primary-light: var(--blue-100);
    --border-default: var(--blue-200);
    --border-hover: var(--blue-300);
    --background-primary: var(--blue-50);
    --background-secondary: var(--white);
    
    /* Stíny - jemnější s modravým nádechem */
    --shadow-sm: 0 1px 3px rgba(66, 74, 93, 0.08);
    --shadow-md: 0 2px 6px rgba(66, 74, 93, 0.10);
    --shadow-lg: 0 4px 12px rgba(66, 74, 93, 0.12);
    --shadow-xl: 0 8px 24px rgba(66, 74, 93, 0.15);
    
    /* Typografie */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Inter', Roboto, Arial, sans-serif;
    --font-size-xs: 11px;
    --font-size-sm: 12px;
    --font-size-base: 13px;
    --font-size-md: 14px;
    --font-size-lg: 15px;
    --font-size-xl: 16px;
    --font-size-2xl: 18px;
    --font-size-3xl: 24px;
    --font-size-4xl: 32px;
    
    /* Spacing */
    --spacing-xs: 4px;
    --spacing-sm: 8px;
    --spacing-md: 12px;
    --spacing-lg: 16px;
    --spacing-xl: 20px;
    --spacing-2xl: 24px;
    --spacing-3xl: 32px;
    --spacing-4xl: 48px;
    
    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 8px;
    --radius-xl: 12px;
    --radius-full: 9999px;
}

/* ===== ZÁKLADNÍ STYLY ===== */
body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--blue-700);
    background-color: var(--background-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== KONTEJNERY A LAYOUT ===== */
.container {
    background: var(--background-secondary);
    border-radius: var(--radius-lg);
    padding: var(--spacing-3xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-default);
}

.section {
    margin-bottom: var(--spacing-3xl);
}

/* ===== TYPOGRAFIE ===== */
h1, h2, h3, h4, h5, h6 {
    color: var(--blue-900);
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
    letter-spacing: -0.02em;
}

h1 {
    font-size: var(--font-size-4xl);
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    background: linear-gradient(135deg, var(--blue-700) 0%, var(--blue-500) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

h2 {
    font-size: var(--font-size-3xl);
    padding-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--blue-100);
    margin-bottom: var(--spacing-xl);
}

h3 {
    font-size: var(--font-size-xl);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--blue-600);
    font-weight: 700;
}

p {
    margin-bottom: var(--spacing-lg);
    line-height: 1.7;
    color: var(--blue-600);
}

/* ===== TLAČÍTKA - ZÁKLADNÍ STYL ===== */
.btn {
    /* Základní vlastnosti */
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: 12px 20px;
    
    /* Vzhled */
    background-color: var(--white);
    color: var(--blue-700);
    border: 1px solid var(--blue-200);
    border-radius: var(--radius-md);
    
    /* Typografie */
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    text-decoration: none;
    
    /* Interakce */
    cursor: pointer;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
    
    /* Reset */
    outline: none;
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
}

/* Hover stav */
.btn:hover {
    background-color: var(--blue-50);
    border-color: var(--blue-300);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* Aktivní/Stisknutý stav */
.btn:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

/* Focus stav */
.btn:focus-visible {
    outline: 2px solid var(--blue-400);
    outline-offset: 2px;
}

/* ===== VARIANTY TLAČÍTEK ===== */

/* Aktivní tlačítko */
.btn.active {
    background-color: var(--blue-700);
    color: var(--white);
    border-color: var(--blue-700);
}
.btn.active:hover {
    background-color: var(--blue-800);
    border-color: var(--blue-800);
}

/* Primární tlačítko */
.btn.primary {
    background-color: var(--blue-700);
    color: var(--white);
    border-color: var(--blue-700);
    box-shadow: var(--shadow-md);
}
.btn.primary:hover {
    background-color: var(--blue-800);
    border-color: var(--blue-800);
    box-shadow: var(--shadow-lg);
}

/* Sekundární tlačítko */
.btn.secondary {
    background-color: var(--blue-100);
    color: var(--blue-700);
    border-color: var(--blue-200);
}
.btn.secondary:hover {
    background-color: var(--blue-200);
    border-color: var(--blue-300);
}

/* Recording/Nebezpečný stav */
.btn.recording,
.btn.danger-active {
    background-color: var(--rose-accent);
    color: var(--white);
    border-color: var(--rose-accent);
    animation: pulse 1.5s infinite;
}

@keyframes pulse {
    0%, 100% { 
        opacity: 1;
        box-shadow: 0 0 0 0 rgba(244, 63, 94, 0.4);
    }
    50% { 
        opacity: 0.9;
        box-shadow: 0 0 0 8px rgba(244, 63, 94, 0);
    }
}

/* ===== VELIKOSTI TLAČÍTEK ===== */
.btn.large {
    padding: 16px 32px;
    font-size: var(--font-size-md);
    border-radius: var(--radius-lg);
}

.btn.small {
    padding: 8px 14px;
    font-size: var(--font-size-xs);
}

.btn.tiny {
    padding: 6px 10px;
    font-size: 10px;
    text-transform: none;
}

/* Pouze ikona */
.btn.icon-only {
    padding: 10px;
    min-width: 40px;
    justify-content: center;
}

.btn.icon-only.small {
    padding: 8px;
    min-width: 32px;
}

/* ===== KATEGORIE S BAREVNÝM AKCENTEM ===== */
.btn.komunikace::before,
.btn.schuzka::before,
.btn.poznamka::before,
.btn.ukol::before,
.btn.special::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    transition: width 0.2s ease;
}

.btn.komunikace::before { background-color: var(--cyan-accent); }
.btn.schuzka::before { background-color: var(--indigo-accent); }
.btn.poznamka::before { background-color: var(--amber-accent); }
.btn.ukol::before { background-color: var(--emerald-accent); }
.btn.special::before { background-color: var(--violet-accent); }

.btn.komunikace:hover::before,
.btn.schuzka:hover::before,
.btn.poznamka:hover::before,
.btn.ukol:hover::before,
.btn.special:hover::before {
    width: 6px;
}

/* ===== IKONY ===== */
.icon {
    color: var(--blue-500);
    font-style: normal;
    filter: none;
    opacity: 0.9;
    transition: all 0.2s ease;
}

.btn:hover .icon {
    opacity: 1;
    transform: scale(1.1);
}

.btn.active .icon,
.btn.primary .icon,
.btn.recording .icon {
    color: var(--white);
    opacity: 1;
}

/* Prioritní kolečka */
.priority-dot {
    display: inline-block;
    width: 12px;
    height: 12px;
    border-radius: 50%;
    margin-right: 8px;
    position: relative;
}

.priority-dot::after {
    content: '';
    position: absolute;
    inset: -2px;
    border-radius: 50%;
    border: 2px solid transparent;
    transition: border-color 0.2s ease;
}

.btn:hover .priority-dot::after {
    border-color: currentColor;
    opacity: 0.3;
}

.priority-high .priority-dot { background-color: var(--rose-accent); }
.priority-normal .priority-dot { background-color: var(--amber-accent); }
.priority-low .priority-dot { background-color: var(--emerald-accent); }

/* ===== FORMULÁŘOVÉ PRVKY ===== */

/* Textové pole */
.input,
.textarea {
    width: 100%;
    padding: var(--spacing-md) var(--spacing-lg);
    border: 2px solid var(--blue-200);
    border-radius: var(--radius-md);
    font-family: var(--font-family);
    font-size: var(--font-size-md);
    color: var(--blue-900);
    background-color: var(--white);
    transition: all 0.2s ease;
    resize: vertical;
}

.textarea {
    min-height: 200px;
    line-height: 1.6;
}

.input:focus,
.textarea:focus {
    outline: none;
    border-color: var(--blue-400);
    background-color: var(--blue-50);
    box-shadow: 0 0 0 3px rgba(66, 74, 93, 0.1);
}

.input::placeholder,
.textarea::placeholder {
    color: var(--blue-300);
}

/* Vyhledávací pole */
.search-input {
    padding: 12px 20px 12px 44px;
    font-size: var(--font-size-md);
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='20' height='20' viewBox='0 0 24 24' fill='none' stroke='%236b7689' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Ccircle cx='11' cy='11' r='8'%3E%3C/circle%3E%3Cpath d='m21 21-4.35-4.35'%3E%3C/path%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: 14px center;
}

/* ===== INFORMAČNÍ BLOKY ===== */

/* Status bar */
.status-bar {
    padding: 14px 20px;
    background-color: var(--blue-100);
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    color: var(--blue-700);
    border: 1px solid var(--blue-200);
    text-align: center;
    font-weight: 500;
}

.status-bar.success {
    background-color: #d1fae5;
    color: var(--emerald-accent);
    border-color: #a7f3d0;
}

.status-bar.error {
    background-color: #fee2e2;
    color: var(--rose-accent);
    border-color: #fecaca;
}

.status-bar.info {
    background-color: var(--blue-100);
    color: var(--blue-700);
    border-color: var(--blue-200);
}

/* Storage info */
.storage-info {
    padding: 12px 18px;
    background: linear-gradient(135deg, var(--blue-50) 0%, var(--white) 100%);
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    color: var(--blue-600);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 1px solid var(--blue-200);
}

.storage-info strong {
    color: var(--blue-700);
    font-weight: 700;
}

/* ===== KOMPONENTY ===== */

/* Toggle/Rozbalovací sekce */
.toggle-section {
    padding: 14px 20px;
    background-color: var(--blue-50);
    border: 1px solid var(--blue-200);
    border-radius: var(--radius-md);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: var(--font-size-md);
    font-weight: 600;
    color: var(--blue-700);
    transition: all 0.2s ease;
}

.toggle-section:hover {
    background-color: var(--blue-100);
    border-color: var(--blue-300);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.toggle-arrow {
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    color: var(--blue-500);
}

.toggle-section.expanded .toggle-arrow {
    transform: rotate(180deg);
}

/* Historie položka */
.history-item {
    background-color: var(--white);
    border: 1px solid var(--blue-200);
    border-radius: var(--radius-md);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-md);
    border-left: 4px solid var(--blue-300);
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

.history-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--blue-400) 0%, transparent 100%);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.history-item:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
    border-left-width: 6px;
}

.history-item:hover::before {
    opacity: 1;
}

/* Barevné akcenty pro typy */
.history-item.komunikace { border-left-color: var(--cyan-accent); }
.history-item.schuzka { border-left-color: var(--indigo-accent); }
.history-item.poznamka { border-left-color: var(--amber-accent); }
.history-item.ukol { border-left-color: var(--emerald-accent); }
.history-item.special { border-left-color: var(--violet-accent); }

.history-item-header {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-sm);
    font-size: var(--font-size-sm);
    color: var(--blue-500);
    font-weight: 500;
}

.history-item-preview {
    font-size: var(--font-size-md);
    color: var(--blue-700);
    line-height: 1.6;
}

/* Filter container */
.filter-container {
    background: linear-gradient(135deg, var(--blue-50) 0%, var(--white) 100%);
    padding: var(--spacing-xl);
    border-radius: var(--radius-lg);
    border: 1px solid var(--blue-200);
}

/* ===== SPECIÁLNÍ KOMPONENTY ===== */

/* Indikátor nahrávání */
.indicator {
    width: 10px;
    height: 10px;
    background-color: var(--blue-300);
    border-radius: 50%;
    display: inline-block;
    transition: all 0.3s ease;
}

.indicator.active {
    background-color: var(--rose-accent);
    box-shadow: 0 0 0 2px rgba(244, 63, 94, 0.3);
    animation: blink 1s infinite;
}

@keyframes blink {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

/* Filter tlačítka */
.btn.filter {
    padding: 8px 16px;
    font-size: var(--font-size-sm);
    background-color: var(--white);
    border-color: var(--blue-200);
    text-transform: none;
    border-radius: var(--radius-full);
}

.btn.filter.active {
    background-color: var(--blue-700);
    color: var(--white);
    border-color: var(--blue-700);
}

/* Badge komponenta */
.badge {
    display: inline-flex;
    align-items: center;
    padding: 4px 10px;
    font-size: var(--font-size-xs);
    font-weight: 600;
    border-radius: var(--radius-full);
    background-color: var(--blue-100);
    color: var(--blue-700);
    border: 1px solid var(--blue-200);
}

.badge.success {
    background-color: #d1fae5;
    color: var(--emerald-accent);
    border-color: #a7f3d0;
}

.badge.warning {
    background-color: #fef3c7;
    color: var(--amber-accent);
    border-color: #fde68a;
}

.badge.error {
    background-color: #fee2e2;
    color: var(--rose-accent);
    border-color: #fecaca;
}

/* Card komponenta */
.card {
    background-color: var(--white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-2xl);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--blue-200);
    transition: all 0.3s ease;
}

.card:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-4px);
}

.card-header {
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 1px solid var(--blue-100);
}

.card-title {
    font-size: var(--font-size-xl);
    font-weight: 700;
    color: var(--blue-900);
}

.card-body {
    color: var(--blue-600);
}

/* ===== UTILITY TŘÍDY ===== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--blue-700); }
.text-secondary { color: var(--blue-500); }
.text-success { color: var(--emerald-accent); }
.text-warning { color: var(--amber-accent); }
.text-error { color: var(--rose-accent); }

.bg-primary { background-color: var(--blue-700); }
.bg-light { background-color: var(--blue-50); }
.bg-white { background-color: var(--white); }

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

/* ===== GRID SYSTEM ===== */
.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

@media (max-width: 768px) {
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

/* ===== PŘEPÍNAČ TÉMAT ===== */

/* Inline varianta */
.theme-switcher {
    display: inline-flex;
    gap: 10px;
    padding: 6px;
    background-color: white;
    border-radius: var(--radius-full);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--blue-200);
}

.theme-btn {
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 50%;
    background-color: transparent;
    cursor: pointer;
    padding: 6px;
    transition: all 0.2s ease;
    position: relative;
}

.theme-btn:hover {
    transform: scale(1.1);
}

.theme-btn.active {
    background-color: var(--blue-50);
}

.theme-btn.active .theme-dot {
    box-shadow: 0 0 0 2px white, 0 0 0 4px var(--blue-400), inset 0 2px 4px rgba(0,0,0,0.1);
}

.theme-dot {
    display: block;
    width: 100%;
    height: 100%;
    border-radius: 50%;
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.1);
    transition: all 0.2s ease;
}

/* Plovoucí varianta */
.theme-switcher-floating {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
}

.theme-toggle-btn {
    width: 52px;
    height: 52px;
    border: none;
    border-radius: 50%;
    background-color: white;
    box-shadow: var(--shadow-xl);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 4px;
    padding: 14px;
    transition: all 0.3s ease;
    flex-wrap: wrap;
    border: 1px solid var(--blue-200);
}

.theme-toggle-btn:hover {
    transform: scale(1.05) rotate(180deg);
    box-shadow: 0 8px 24px rgba(66, 74, 93, 0.2);
}

.theme-toggle-btn .theme-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    flex-shrink: 0;
}

.theme-dropdown {
    position: absolute;
    top: 64px;
    right: 0;
    background-color: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: 10px;
    min-width: 180px;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s ease;
    border: 1px solid var(--blue-200);
}

.theme-switcher-floating:hover .theme-dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.theme-dropdown .theme-btn {
    width: 100%;
    justify-content: flex-start;
    gap: 12px;
    padding: 10px 14px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
}

.theme-dropdown .theme-btn:hover {
    background-color: var(--blue-50);
}

.theme-dropdown .theme-dot {
    width: 20px;
    height: 20px;
    border-radius: 50%;
    flex-shrink: 0;
}

.theme-name {
    font-size: var(--font-size-base);
    color: var(--blue-700);
    font-weight: 500;
}

/* ===== ANIMACE ===== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
}

@keyframes slideInRight {
    from { opacity: 0; transform: translateX(20px); }
    to { opacity: 1; transform: translateX(0); }
}

.animate-fadeIn { animation: fadeIn 0.5s ease-out; }
.animate-slideInLeft { animation: slideInLeft 0.5s ease-out; }
.animate-slideInRight { animation: slideInRight 0.5s ease-out; }

/* ===== DEMO STYLES ===== */
.demo-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 40px 20px;
}

.demo-section {
    background: var(--white);
    border-radius: var(--radius-xl);
    padding: var(--spacing-4xl);
    margin-bottom: var(--spacing-3xl);
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--blue-200);
}

.button-group {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
    margin-bottom: var(--spacing-xl);
    align-items: center;
}

.code-block {
    background-color: var(--blue-950);
    color: #e0e6f1;
    padding: var(--spacing-2xl);
    border-radius: var(--radius-lg);
    font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
    font-size: var(--font-size-sm);
    overflow-x: auto;
    margin: var(--spacing-lg) 0;
    border: 1px solid var(--blue-800);
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

.color-palette {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: var(--spacing-lg);
    margin-bottom: var(--spacing-3xl);
}

.color-box {
    text-align: center;
}

.color-swatch {
    height: 80px;
    border-radius: var(--radius-lg);
    border: 1px solid var(--blue-200);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: var(--font-size-sm);
    font-weight: 600;
    transition: all 0.2s ease;
    position: relative;
    overflow: hidden;
}

.color-swatch::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 100%);
    opacity: 0;
    transition: opacity 0.2s ease;
}

.color-swatch:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.color-swatch:hover::before {
    opacity: 1;
}

.color-name {
    font-size: var(--font-size-sm);
    color: var(--blue-600);
    font-weight: 500;
}

/* ===== RESPONZIVNÍ DESIGN ===== */
@media (max-width: 768px) {
    .demo-container {
        padding: 20px 10px;
    }
    
    .demo-section {
        padding: var(--spacing-2xl);
    }
    
    h1 {
        font-size: var(--font-size-3xl);
    }
    
    h2 {
        font-size: var(--font-size-2xl);
    }
    
    .button-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
}