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

:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --success-color: #27ae60;
    --warning-color: #f39c12;
    --text-color: #333;
    --light-text: #666;
    --bg-color: #f8f9fa;
    --white: #ffffff;
    --border-color: #e9ecef;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
    --game-bg: #1a1a2e;
    --snake-color: #27ae60;
    --food-color: #e74c3c;
    --grid-color: rgba(255, 255, 255, 0.1);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    min-height: 100vh;
    color: var(--text-color);
}

.game-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 30px;
    background: var(--white);
    padding: 20px 30px;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.game-header h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    font-weight: 700;
}

.back-btn {
    text-decoration: none;
    color: var(--secondary-color);
    font-weight: 600;
    font-size: 1.1rem;
    transition: var(--transition);
    padding: 10px 20px;
    border-radius: 8px;
    border: 2px solid var(--secondary-color);
}

.back-btn:hover {
    background: var(--secondary-color);
    color: var(--white);
    transform: translateX(-5px);
}

.game-content {
    display: grid;
    grid-template-columns: 1fr 400px 1fr;
    gap: 30px;
    align-items: start;
}

.game-info {
    background: var(--white);
    padding: 25px;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.game-info > div {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid var(--border-color);
}

.game-info > div:last-child {
    border-bottom: none;
}

.label {
    font-weight: 600;
    color: var(--text-color);
}

#score, #highScore, #speed {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.game-area {
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}

#gameCanvas {
    background: var(--game-bg);
    border: 4px solid var(--white);
    border-radius: 15px;
    box-shadow: var(--shadow);
    position: relative;
}

.game-over-screen, .start-screen {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: rgba(255, 255, 255, 0.95);
    padding: 40px;
    border-radius: 15px;
    text-align: center;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
    backdrop-filter: blur(10px);
    z-index: 10;
}

.game-over-screen.hidden, .start-screen.hidden {
    display: none;
}

.game-over-screen h2, .start-screen h2 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-size: 2rem;
}

.game-over-screen p, .start-screen p {
    margin-bottom: 10px;
    color: var(--light-text);
    font-size: 1.1rem;
}

.game-btn {
    background: var(--accent-color);
    color: var(--white);
    border: none;
    padding: 12px 30px;
    border-radius: 25px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    margin-top: 20px;
}

.game-btn:hover {
    background: #c0392b;
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(231, 76, 60, 0.3);
}

.game-controls {
    background: var(--white);
    padding: 25px;
    border-radius: 15px;
    box-shadow: var(--shadow);
}

.controls-section h3 {
    color: var(--primary-color);
    margin-bottom: 20px;
    text-align: center;
    font-weight: 600;
}

.control-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
    max-width: 150px;
    margin: 0 auto 15px;
}

.control-btn {
    background: var(--secondary-color);
    color: var(--white);
    border: none;
    padding: 12px;
    border-radius: 8px;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
}

.control-btn:hover, .control-btn:active {
    background: var(--primary-color);
    transform: scale(0.95);
}

.control-btn[data-direction="up"] {
    grid-column: 2;
}

.control-btn[data-direction="left"] {
    grid-column: 1;
    grid-row: 2;
}

.control-btn[data-direction="down"] {
    grid-column: 2;
    grid-row: 2;
}

.control-btn[data-direction="right"] {
    grid-column: 3;
    grid-row: 2;
}

.control-hint {
    text-align: center;
    color: var(--light-text);
    font-size: 0.9rem;
    margin-bottom: 20px;
}

.game-actions {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.action-btn {
    background: var(--warning-color);
    color: var(--white);
    border: none;
    padding: 10px 20px;
    border-radius: 8px;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.action-btn:hover {
    background: #e67e22;
    transform: translateY(-1px);
}

.game-instructions {
    grid-column: 1 / -1;
    background: var(--white);
    padding: 25px;
    border-radius: 15px;
    box-shadow: var(--shadow);
    margin-top: 20px;
}

.game-instructions h3 {
    color: var(--primary-color);
    margin-bottom: 15px;
    font-weight: 600;
}

.game-instructions ul {
    list-style: none;
    padding: 0;
}

.game-instructions li {
    padding: 8px 0;
    color: var(--light-text);
    position: relative;
    padding-left: 25px;
}

.game-instructions li::before {
    content: "🎮";
    position: absolute;
    left: 0;
    top: 8px;
}

.new-high-score {
    color: var(--success-color) !important;
    animation: pulse 2s infinite;
}

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

.paused-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--white);
    font-size: 2rem;
    font-weight: bold;
    border-radius: 15px;
    backdrop-filter: blur(5px);
}

@media (max-width: 768px) {
    .game-content {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    #gameCanvas {
        width: 100%;
        max-width: 350px;
        height: 350px;
    }
    
    .game-header {
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }
    
    .game-header h1 {
        font-size: 2rem;
    }
    
    .game-over-screen, .start-screen {
        padding: 30px 20px;
        width: 90%;
        max-width: 300px;
    }
    
    .control-grid {
        max-width: 120px;
    }
    
    .control-btn {
        padding: 8px;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .game-container {
        padding: 10px;
    }
    
    #gameCanvas {
        max-width: 280px;
        height: 280px;
    }
    
    .game-header h1 {
        font-size: 1.8rem;
    }
    
    .game-over-screen, .start-screen {
        padding: 20px 15px;
    }
    
    .game-over-screen h2, .start-screen h2 {
        font-size: 1.5rem;
    }
}