/* ==================== CSS Variables ==================== */
:root {
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --accent-color: #4facfe;
    --success-color: #00f5a0;
    --warning-color: #ffb347;
    --danger-color: #ff6b6b;
    --dark-color: #2c3e50;
    --light-color: #ecf0f1;
    --bg-primary: #0f0f23;
    --bg-secondary: #1a1a2e;
    --bg-tertiary: #16213e;
    --text-primary: #ffffff;
    --text-secondary: #b8c6db;
    --border-color: rgba(255, 255, 255, 0.1);
    --shadow-color: rgba(0, 0, 0, 0.3);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --border-radius: 12px;
    --game-width: 300px;
    --game-height: 600px;
    --piece-size: 30px;
}

/* ==================== Reset & Base Styles ==================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Noto Sans SC', 'Orbitron', sans-serif;
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 50%, var(--bg-tertiary) 100%);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    font-size: 14px;
    line-height: 1.6;
}

/* ==================== Game Container ==================== */
.game-container {
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    position: relative;
}

/* ==================== Header ==================== */
.game-header {
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(10px);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
}

.game-title {
    font-family: 'Orbitron', monospace;
    font-size: 1.8rem;
    font-weight: 900;
    background: linear-gradient(45deg, var(--accent-color), var(--primary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.game-title i {
    color: var(--accent-color);
    -webkit-text-fill-color: var(--accent-color);
}

.header-controls {
    display: flex;
    gap: 0.5rem;
}

.header-btn {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 0.5rem 1rem;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 0.3rem;
    font-size: 0.9rem;
}

.header-btn:hover {
    background: rgba(255, 255, 255, 0.2);
    transform: translateY(-2px);
}

/* ==================== Main Game Area ==================== */
.game-main {
    flex: 1;
    display: flex;
    gap: 2rem;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
    align-items: flex-start;
    justify-content: center;
}

.game-area {
    flex: 0 0 auto;
    display: flex;
    justify-content: center;
    align-items: center;
    margin-right: 1rem;
}

.canvas-wrapper {
    position: relative;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: 0 20px 40px var(--shadow-color);
}

.game-canvas {
    width: var(--game-width);
    height: var(--game-height);
    background: linear-gradient(180deg, #0a0a0a 0%, #1a1a1a 100%);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    position: relative;
    overflow: hidden;
}

/* ==================== Game Overlay ==================== */
.game-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    z-index: 10;
    cursor: pointer;
}

.game-overlay.hidden {
    opacity: 0;
    pointer-events: none;
}

.overlay-content {
    text-align: center;
    color: var(--text-primary);
}

.overlay-content i {
    font-size: 4rem;
    color: var(--accent-color);
    margin-bottom: 1rem;
    animation: pulse 2s infinite;
    transition: var(--transition);
}

.game-overlay:hover .overlay-content i {
    transform: scale(1.1);
    color: var(--success-color);
}

.overlay-content p {
    font-size: 1.2rem;
    margin-bottom: 1rem;
}

.controls-hint {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    margin-top: 1rem;
}

.controls-hint span {
    display: flex;
    align-items: center;
    gap: 0.3rem;
    justify-content: center;
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ==================== Sidebar ==================== */
.game-sidebar {
    width: 300px;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
    flex-shrink: 0;
}

/* Next Piece Panel */
.next-piece-panel {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    text-align: center;
}

.next-piece-panel h3 {
    font-size: 1rem;
    margin-bottom: 1rem;
    color: var(--text-secondary);
/* Project: GameHub */
    font-family: 'Orbitron', monospace;
}

.next-shape-preview {
    width: 120px;
    height: 120px;
    background: linear-gradient(180deg, #0a0a0a 0%, #1a1a1a 100%);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    margin: 0 auto;
/* Email: 2952671670@qq.com */
    position: relative;
    overflow: hidden;
}

/* Game Stats */
.game-stats {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.stat-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.stat-item:last-child {
    border-bottom: none;
}

.stat-label {
    font-size: 0.9rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.stat-value {
    font-family: 'Orbitron', monospace;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--accent-color);
}

/* Control Panel */
.control-panel {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.control-btn {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    border: none;
    border-radius: var(--border-radius);
    padding: 0.8rem 1.5rem;
    color: var(--text-primary);
    font-size: 0.9rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    position: relative;
    overflow: hidden;
}

.control-btn:before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s;
}

.control-btn:hover:before {
    left: 100%;
}

.control-btn:hover {
    transform: translateY(-2px);
/* Contact: 2952671670@qq.com */
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.2);
}

.control-btn:active {
    transform: translateY(0);
}

.control-btn:disabled {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-secondary);
    cursor: not-allowed;
    transform: none;
}

.control-btn.primary {
    background: linear-gradient(135deg, var(--success-color), var(--accent-color));
}

.control-btn.secondary {
    background: linear-gradient(135deg, var(--warning-color), #ff8a65);
}

/* Game Tips */
.game-tips {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.tip-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

kbd {
    background: rgba(255, 255, 255, 0.1);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 0.2rem 0.4rem;
    font-family: 'Orbitron', monospace;
    font-size: 0.7rem;
    min-width: 24px;
    text-align: center;
}

/* ==================== Game Pieces ==================== */
.piece, .square {
    position: absolute;
    width: var(--piece-size);

/* Developer: SinceraXY from CUPB */

    height: var(--piece-size);
    border: 1px solid rgba(255, 255, 255, 0.3);
    border-radius: 3px;
    transition: all 0.1s ease;
}

.type0 { /* T-piece */
    background: linear-gradient(135deg, #a855f7, #7c3aed);
    box-shadow: 0 0 10px rgba(168, 85, 247, 0.3);
}

.type1 { /* I-piece */
    background: linear-gradient(135deg, #06b6d4, #0891b2);
    box-shadow: 0 0 10px rgba(6, 182, 212, 0.3);
}

.type2 { /* L-piece */
    background: linear-gradient(135deg, #f59e0b, #d97706);
    box-shadow: 0 0 10px rgba(245, 158, 11, 0.3);
}

.type3 { /* J-piece */
    background: linear-gradient(135deg, #3b82f6, #2563eb);
    box-shadow: 0 0 10px rgba(59, 130, 246, 0.3);
}

.type4 { /* S-piece */
    background: linear-gradient(135deg, #10b981, #059669);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.3);
}

.type5 { /* Z-piece */
    background: linear-gradient(135deg, #ef4444, #dc2626);
    box-shadow: 0 0 10px rgba(239, 68, 68, 0.3);
}

.type6 { /* O-piece */
    background: linear-gradient(135deg, #eab308, #ca8a04);
    box-shadow: 0 0 10px rgba(234, 179, 8, 0.3);
}

/* ==================== Rules Sidebar ==================== */
.rules-sidebar {
    position: fixed;
    top: 0;
    left: -400px;
    width: 400px;
    height: 100vh;
    background: rgba(255, 255, 255, 0.05);
    backdrop-filter: blur(20px);
    border-right: 1px solid var(--border-color);
    transition: var(--transition);
    z-index: 1000;
    overflow-y: auto;
}

.rules-sidebar.show {
    left: 0;
}

.rules-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: rgba(0, 0, 0, 0.2);
}

.rules-header h2 {
    font-family: 'Orbitron', monospace;
    font-size: 1.3rem;
    color: var(--accent-color);
}

.close-btn {
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 50%;
    width: 32px;
    height: 32px;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-btn:hover {
    background: var(--danger-color);
    transform: rotate(90deg);
}

.rules-content {
    padding: 1.5rem;
}

.rule-section {
    margin-bottom: 2rem;
}

.rule-section h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.rule-section ul {
    list-style: none;
}

.rule-section li {
    padding: 0.5rem 0;
    padding-left: 1rem;
    position: relative;
    color: var(--text-secondary);
}

.rule-section li:before {
    content: '▸';
    position: absolute;
    left: 0;
    color: var(--accent-color);
}

/* ==================== Game Over Modal ==================== */
.game-over-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(5px);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: var(--transition);
    z-index: 2000;
}

.game-over-modal.active {
    opacity: 1;
    pointer-events: all;
}

.modal-content {
    background: linear-gradient(135deg, var(--bg-secondary), var(--bg-tertiary));
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem;
    text-align: center;
    max-width: 400px;
    width: 90%;
    transform: translateY(-20px);
    transition: var(--transition);
}

.game-over-modal.active .modal-content {
    transform: translateY(0);
}

.modal-content h2 {
    font-family: 'Orbitron', monospace;
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: var(--accent-color);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
}

.final-stats {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.final-stat {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.8rem;
    background: rgba(255, 255, 255, 0.05);
    border-radius: var(--border-radius);
}

.final-stat .label {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.final-stat .value {
    font-family: 'Orbitron', monospace;
    font-weight: 700;
    color: var(--accent-color);
}

.modal-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* ==================== Animations ==================== */
@keyframes pulse {
    0%, 100% { transform: scale(1); opacity: 1; }
    50% { transform: scale(1.1); opacity: 0.8; }
}

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

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes glow {
    0%, 100% { box-shadow: 0 0 10px currentColor; }
    50% { box-shadow: 0 0 20px currentColor, 0 0 30px currentColor; }
}

@keyframes lineClear {
    0% { 
        background: rgba(255, 255, 255, 0);
        transform: scaleY(1);
    }
    50% { 
        background: rgba(255, 255, 255, 0.8);
        transform: scaleY(1.1);
    }
    100% { 
        background: rgba(255, 255, 255, 0);
        transform: scaleY(0);
    }
}

@keyframes scorePopup {
    0% {
        transform: translateY(0) scale(1);
        opacity: 0;
    }
    50% {
        transform: translateY(-20px) scale(1.2);
        opacity: 1;
    }
    100% {
        transform: translateY(-40px) scale(1);
        opacity: 0;
    }
}

.piece-clear {
    animation: glow 0.5s ease-in-out;
}

.line-clear-animation {
    animation: lineClear 0.6s ease-out;
}

.score-popup {
    animation: scorePopup 1s ease-out;
}

/* ==================== Responsive Design ==================== */
@media (max-width: 768px) {
    .game-main {
        flex-direction: column;
        padding: 1rem;
        gap: 1rem;
    }
    
    .game-sidebar {
        width: 100%;
        order: -1;
    }
    
    .game-stats {
        flex-direction: row;
        flex-wrap: wrap;
    }
    
    .stat-item {
        flex: 1;
        min-width: 120px;
        border-bottom: none;
        border-right: 1px solid var(--border-color);
        padding: 0.5rem;
        text-align: center;
        flex-direction: column;
        gap: 0.2rem;
    }
    
    .stat-item:last-child {
        border-right: none;
    }
    
    .control-panel {
        flex-direction: row;
    }
    
    .rules-sidebar {
        width: 100%;
        left: -100%;
    }
    
    :root {
        --game-width: 250px;
        --game-height: 500px;
        --piece-size: 25px;
    }
}