/* ============================================
   DESIGN TOKENS
   ============================================ */
:root {
    /* Colors */
    --bg-primary: #0f0f1a;
    --bg-secondary: #1a1a2e;
    --bg-card: rgba(255, 255, 255, 0.05);
    --bg-glass: rgba(255, 255, 255, 0.08);
    
    --text-primary: #ffffff;
    --text-secondary: rgba(255, 255, 255, 0.7);
    --text-muted: rgba(255, 255, 255, 0.5);
    
    --accent-pink: #ff6b9d;
    --accent-purple: #9b59b6;
    --accent-blue: #667eea;
    --accent-orange: #f39c12;
    
    --gradient-love: linear-gradient(135deg, #ff6b9d 0%, #c44569 100%);
    --gradient-deep: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-romance: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
    --gradient-spicy: linear-gradient(135deg, #f39c12 0%, #e74c3c 100%);
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-full: 50%;
    
    /* Shadows */
    --shadow-soft: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-glow: 0 0 40px rgba(255, 107, 157, 0.3);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

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

html, body {
    height: 100%;
    overflow: hidden;
}

body {
    font-family: 'Outfit', sans-serif;
    background: var(--bg-primary);
    background-image: 
        radial-gradient(ellipse at top, rgba(102, 126, 234, 0.15) 0%, transparent 50%),
        radial-gradient(ellipse at bottom, rgba(255, 107, 157, 0.1) 0%, transparent 50%);
    color: var(--text-primary);
    min-height: 100vh;
    min-height: 100dvh;
}

/* ============================================
   SCREENS
   ============================================ */
.screen {
    display: none;
    width: 100%;
    height: 100vh;
    height: 100dvh;
}

.screen.active {
    display: flex;
    flex-direction: column;
}

/* ============================================
   PASSWORD SCREEN
   ============================================ */
#password-screen {
    justify-content: center;
    align-items: center;
    padding: var(--spacing-md);
}

.password-container {
    text-align: center;
    max-width: 360px;
    width: 100%;
}

.logo {
    font-size: 4rem;
    margin-bottom: var(--spacing-sm);
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.password-container h1 {
    font-size: 2rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
    background: var(--gradient-love);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.subtitle {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

.password-input-wrapper {
    display: flex;
    gap: var(--spacing-xs);
    margin-bottom: var(--spacing-sm);
}

#password-input {
    flex: 1;
    padding: var(--spacing-sm);
    border: 2px solid var(--bg-glass);
    border-radius: var(--radius-md);
    background: var(--bg-glass);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 1rem;
    outline: none;
    transition: var(--transition-fast);
}

#password-input:focus {
    border-color: var(--accent-pink);
    box-shadow: 0 0 20px rgba(255, 107, 157, 0.2);
}

#password-input::placeholder {
    color: var(--text-muted);
}

.btn-primary {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--gradient-love);
    border: none;
    border-radius: var(--radius-md);
    color: white;
    font-family: inherit;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-primary:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-glow);
}

.btn-primary:active {
    transform: scale(0.98);
}

.error-text {
    color: #e74c3c;
    font-size: 0.9rem;
    animation: shake 0.5s ease;
}

.hidden {
    display: none !important;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

/* ============================================
   LOBBY SCREEN
   ============================================ */
#lobby-screen {
    padding: var(--spacing-md);
    overflow-y: auto;
}

.lobby-header {
    text-align: center;
    padding: var(--spacing-lg) 0;
}

.lobby-header h1 {
    font-size: 1.8rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.categories-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
    padding-bottom: var(--spacing-xl);
}

/* Category Styles */
.category {
    background: var(--bg-glass);
    border-radius: var(--radius-lg);
    padding: var(--spacing-md);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.1);
}

.category-header {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
    cursor: pointer;
}

.category-emoji {
    font-size: 1.8rem;
}

.category-title {
    font-size: 1.2rem;
    font-weight: 600;
}

.decks-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
    gap: var(--spacing-sm);
}

.deck-card {
    position: relative;
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    text-align: center;
    cursor: pointer;
    transition: var(--transition-normal);
    overflow: hidden;
}

.deck-card::before {
    content: '';
    position: absolute;
    inset: 0;
    opacity: 0.9;
    z-index: 0;
    transition: var(--transition-fast);
}

.deck-card:hover::before {
    opacity: 1;
}

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

.deck-card:active {
    transform: translateY(0) scale(0.98);
}

.deck-card-content {
    position: relative;
    z-index: 1;
}

.deck-card .deck-emoji {
    font-size: 2rem;
    margin-bottom: var(--spacing-xs);
}

.deck-card .deck-name {
    font-size: 0.9rem;
    font-weight: 500;
    line-height: 1.3;
}

.deck-card .deck-count {
    font-size: 0.75rem;
    color: rgba(255, 255, 255, 0.7);
    margin-top: 4px;
}

/* Category Gradients */
.category-love .deck-card::before { background: var(--gradient-love); }
.category-deep .deck-card::before { background: var(--gradient-deep); }
.category-romance .deck-card::before { background: var(--gradient-romance); }
.category-spicy .deck-card::before { background: var(--gradient-spicy); }

/* ============================================
   DECK SCREEN
   ============================================ */
#deck-screen {
    padding: var(--spacing-sm);
}

.deck-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-sm) 0;
    margin-bottom: var(--spacing-sm);
}

.btn-back {
    background: var(--bg-glass);
    border: none;
    color: var(--text-primary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-back:hover {
    background: rgba(255, 255, 255, 0.15);
}

#deck-title {
    font-size: 1.1rem;
    font-weight: 600;
    text-align: center;
    flex: 1;
    padding: 0 var(--spacing-sm);
}

.card-counter {
    background: var(--bg-glass);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* Cards Container */
.cards-container {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    position: relative;
}

.cards-wrapper {
    position: relative;
    width: 100%;
    max-width: 400px;
    height: 100%;
    max-height: 500px;
}

.question-card {
    position: absolute;
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    text-align: center;
    font-size: 1.3rem;
    line-height: 1.5;
    font-weight: 400;
    cursor: grab;
    user-select: none;
    transition: transform 0.3s ease, opacity 0.3s ease;
    touch-action: pan-y;
}

.question-card:active {
    cursor: grabbing;
}

.question-card.current {
    z-index: 10;
}

.question-card.prev {
    transform: translateX(-105%) scale(0.9);
    opacity: 0.5;
    z-index: 5;
}

.question-card.next {
    transform: translateX(105%) scale(0.9);
    opacity: 0.5;
    z-index: 5;
}

.question-card.hidden-left {
    transform: translateX(-200%);
    opacity: 0;
}

.question-card.hidden-right {
    transform: translateX(200%);
    opacity: 0;
}

/* Card Gradients by Category */
.card-love { background: linear-gradient(145deg, rgba(255, 107, 157, 0.2), rgba(196, 69, 105, 0.3)); }
.card-deep { background: linear-gradient(145deg, rgba(102, 126, 234, 0.2), rgba(118, 75, 162, 0.3)); }
.card-romance { background: linear-gradient(145deg, rgba(240, 147, 251, 0.2), rgba(245, 87, 108, 0.3)); }
.card-spicy { background: linear-gradient(145deg, rgba(243, 156, 18, 0.2), rgba(231, 76, 60, 0.3)); }

/* Swipe Hints */
.swipe-hints {
    display: flex;
    justify-content: space-between;
    padding: var(--spacing-sm);
    color: var(--text-muted);
    font-size: 0.8rem;
}

/* Deck Controls */
.deck-controls {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-md);
    padding: var(--spacing-md) 0;
}

.btn-nav {
    width: 50px;
    height: 50px;
    border-radius: var(--radius-full);
    background: var(--bg-glass);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-nav:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: scale(1.1);
}

.btn-nav:active {
    transform: scale(0.95);
}

.btn-shuffle {
    padding: var(--spacing-sm) var(--spacing-md);
    background: var(--bg-glass);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    font-family: inherit;
    font-size: 0.9rem;
    cursor: pointer;
    transition: var(--transition-fast);
}

.btn-shuffle:hover {
    background: rgba(255, 255, 255, 0.15);
}

/* ============================================
   RESPONSIVE
   ============================================ */
@media (min-width: 768px) {
    .decks-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
    }
    
    .question-card {
        font-size: 1.5rem;
    }
    
    .cards-wrapper {
        max-height: 550px;
    }
}

@media (max-height: 600px) {
    .cards-wrapper {
        max-height: 300px;
    }
    
    .question-card {
        font-size: 1.1rem;
        padding: var(--spacing-md);
    }
}