* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 50%, #0f3460 100%);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
}

.game-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    position: relative;
}

.game-header h1 {
    color: #00d4ff;
    font-size: 2.5rem;
    text-shadow: 0 0 20px #00d4ff, 0 0 40px #00d4ff;
    letter-spacing: 8px;
}

.game-content {
    display: flex;
    gap: 20px;
    align-items: flex-start;
}

.side-panel {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.hold-box, .next-box, .stats-box {
    background: rgba(0, 0, 0, 0.6);
    border: 2px solid #00d4ff;
    border-radius: 10px;
    padding: 15px;
    box-shadow: 0 0 15px rgba(0, 212, 255, 0.3);
}

.hold-box h3, .next-box h3 {
    color: #00d4ff;
    text-align: center;
    margin-bottom: 10px;
    font-size: 1rem;
    letter-spacing: 3px;
}

#holdCanvas, #nextCanvas {
    display: block;
    margin: 0 auto;
    background: rgba(0, 0, 0, 0.5);
    border-radius: 5px;
}

.main-board {
    position: relative;
}

#gameCanvas {
    display: block;
    background: rgba(0, 0, 0, 0.8);
    border: 3px solid #00d4ff;
    border-radius: 5px;
    box-shadow: 0 0 30px rgba(0, 212, 255, 0.5), inset 0 0 50px rgba(0, 0, 0, 0.5);
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    border-radius: 5px;
}

.overlay h2 {
    color: #ff6b6b;
    font-size: 2rem;
    margin-bottom: 20px;
    text-shadow: 0 0 10px #ff6b6b;
}

.overlay p {
    color: #fff;
    margin-bottom: 20px;
    font-size: 1.2rem;
}

.overlay button {
    padding: 15px 40px;
    font-size: 1.2rem;
    background: linear-gradient(135deg, #00d4ff, #0099cc);
    color: #fff;
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.overlay button:hover {
    transform: scale(1.1);
    box-shadow: 0 0 20px #00d4ff;
}

.hidden {
    display: none !important;
}

.stats-box {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-label {
    color: #888;
    font-size: 0.8rem;
    letter-spacing: 2px;
}

.stat-value {
    color: #00d4ff;
    font-size: 1.5rem;
    font-weight: bold;
    text-shadow: 0 0 10px #00d4ff;
}

.start-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.95);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    z-index: 100;
}

.start-screen h2 {
    color: #00d4ff;
    font-size: 3rem;
    margin-bottom: 20px;
    text-shadow: 0 0 30px #00d4ff;
    letter-spacing: 10px;
}

.start-screen > p {
    color: #888;
    margin-bottom: 30px;
    font-size: 1.2rem;
}

.controls-info {
    background: rgba(0, 212, 255, 0.1);
    padding: 20px 40px;
    border-radius: 10px;
    margin-bottom: 30px;
    border: 1px solid rgba(0, 212, 255, 0.3);
}

.controls-info p {
    color: #fff;
    margin: 8px 0;
    font-size: 1rem;
}

.start-screen button {
    padding: 20px 60px;
    font-size: 1.5rem;
    background: linear-gradient(135deg, #00d4ff, #0099cc);
    color: #fff;
    border: none;
    border-radius: 40px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 3px;
    font-weight: bold;
}

.start-screen button:hover {
    transform: scale(1.1);
    box-shadow: 0 0 30px #00d4ff;
}

.mobile-controls {
    display: none;
    gap: 10px;
    flex-wrap: wrap;
    justify-content: center;
    margin-top: 20px;
}

.control-btn {
    width: 60px;
    height: 60px;
    font-size: 1.5rem;
    background: linear-gradient(135deg, #00d4ff, #0099cc);
    color: #fff;
    border: none;
    border-radius: 15px;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    justify-content: center;
    align-items: center;
}

.control-btn:active {
    transform: scale(0.9);
    background: #0099cc;
}

/* Responsive Design */
@media (max-width: 768px) {
    .game-header h1 {
        font-size: 1.8rem;
        letter-spacing: 5px;
    }
    
    .game-content {
        flex-direction: column;
        align-items: center;
    }
    
    .side-panel {
        flex-direction: row;
        justify-content: center;
    }
    
    .left-panel {
        order: 2;
    }
    
    .main-board {
        order: 1;
    }
    
    .right-panel {
        order: 3;
    }
    
    #gameCanvas {
        width: 240px;
        height: 480px;
    }
    
    .mobile-controls {
        display: flex;
    }
    
    .start-screen h2 {
        font-size: 2rem;
    }
    
    .controls-info {
        padding: 15px 25px;
    }
    
    .controls-info p {
        font-size: 0.9rem;
    }
}

@media (max-width: 480px) {
    body {
        padding: 10px;
    }
    
    .game-header h1 {
        font-size: 1.5rem;
    }
    
    #gameCanvas {
        width: 200px;
        height: 400px;
    }
    
    .control-btn {
        width: 50px;
        height: 50px;
        font-size: 1.2rem;
    }
    
    .hold-box, .next-box, .stats-box {
        padding: 10px;
    }
    
    #holdCanvas {
        width: 60px;
        height: 60px;
    }
    
    #nextCanvas {
        width: 60px;
        height: 180px;
    }
}

/* Animation for line clear */
@keyframes lineClear {
    0% {
        background: #fff;
        transform: scaleX(1);
    }
    50% {
        background: #00d4ff;
        transform: scaleX(1.1);
    }
    100% {
        background: transparent;
        transform: scaleX(0);
    }
}

/* Ghost piece effect */
.ghost-piece {
    opacity: 0.3;
}