:root {
    --bg-color: #0a0a1a;
    --grid-color: #1a1a3a;
    --snake-head: #00ff88;
    --snake-body: #00cc66;
    --food-normal: #ff6b6b;
    --food-special: #ffd93d;
    --score-text: #00ffff;
    --accent: #ff00ff;
    --text-color: #ffffff;
    --obstacle-color: #555577;
}

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

body {
    font-family: 'Courier New', monospace;
    background: var(--bg-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--text-color);
    overflow: hidden;
    position: relative;
}

body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: repeating-linear-gradient(
        0deg,
        transparent,
        transparent 2px,
        rgba(0, 255, 255, 0.03) 2px,
        rgba(0, 255, 255, 0.03) 4px
    );
    pointer-events: none;
    z-index: 1000;
}

.game-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 12px;
    padding: 8px;
    width: 100vw;
    height: 100vh;
    min-height: 100vh;
    box-sizing: border-box;
}

.title {
    font-size: 24px;
    text-align: center;
    color: var(--snake-head);
    text-shadow:
        0 0 10px var(--snake-head),
        0 0 20px var(--snake-head),
        0 0 40px var(--snake-head);
    animation: titleGlow 2s ease-in-out infinite alternate;
    letter-spacing: 2px;
}

@keyframes titleGlow {
    from {
        text-shadow:
            0 0 10px var(--snake-head),
            0 0 20px var(--snake-head),
            0 0 40px var(--snake-head);
    }
    to {
        text-shadow:
            0 0 5px var(--snake-head),
            0 0 10px var(--snake-head),
            0 0 20px var(--snake-head);
    }
}

.score-board {
    display: flex;
    gap: 40px;
    font-size: 12px;
    color: var(--score-text);
    text-shadow: 0 0 10px var(--score-text);
}

.score-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 5px;
}

.score-label {
    font-size: 10px;
    color: var(--accent);
}

.score-value {
    font-size: 16px;
}

.canvas-wrapper {
    position: relative;
    border: 3px solid var(--accent);
    box-shadow:
        0 0 20px var(--accent),
        inset 0 0 20px rgba(255, 0, 255, 0.2);
    border-radius: 4px;
}

canvas {
    display: block;
    background: var(--bg-color);
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: rgba(10, 10, 26, 0.9);
    gap: 20px;
    opacity: 1;
    transition: opacity 0.3s;
}

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

.overlay-title {
    font-size: 18px;
    color: var(--snake-head);
    text-shadow: 0 0 10px var(--snake-head);
}

.overlay-score {
    font-size: 14px;
    color: var(--score-text);
}

.overlay-hint {
    font-size: 10px;
    color: var(--accent);
    animation: blink 1s infinite;
}

@keyframes blink {
    0%, 50% { opacity: 1; }
    51%, 100% { opacity: 0.3; }
}

.controls {
    display: flex;
    gap: 20px;
    margin-top: 10px;
}

.btn {
    font-family: 'Courier New', monospace;
    font-size: 10px;
    padding: 12px 20px;
    border: 2px solid var(--snake-head);
    background: transparent;
    color: var(--snake-head);
    cursor: pointer;
    text-shadow: 0 0 5px var(--snake-head);
    box-shadow: 0 0 10px rgba(0, 255, 136, 0.3);
    transition: all 0.2s;
}

.btn:hover {
    background: var(--snake-head);
    color: var(--bg-color);
    box-shadow: 0 0 20px var(--snake-head);
}

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

.btn.secondary {
    border-color: var(--accent);
    color: var(--accent);
    text-shadow: 0 0 5px var(--accent);
    box-shadow: 0 0 10px rgba(255, 0, 255, 0.3);
}

.btn.secondary:hover {
    background: var(--accent);
    color: var(--bg-color);
    box-shadow: 0 0 20px var(--accent);
}

.instructions {
    font-size: 8px;
    color: var(--grid-color);
    text-align: center;
    margin-top: 10px;
    line-height: 1.8;
}

.new-high {
    color: var(--food-special) !important;
    text-shadow: 0 0 10px var(--food-special) !important;
    animation: newHigh 0.5s ease-in-out infinite alternate;
}

@keyframes newHigh {
    from { transform: scale(1); }
    to { transform: scale(1.1); }
}

.shake {
    animation: shake 0.5s ease-in-out;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    20% { transform: translateX(-10px); }
    40% { transform: translateX(10px); }
    60% { transform: translateX(-10px); }
    80% { transform: translateX(10px); }
}

.combo-display {
    position: absolute;
    top: 5px;
    right: 5px;
    font-size: 14px;
    color: #ff00ff;
    text-shadow: 0 0 10px #ff00ff;
    opacity: 0;
    transition: opacity 0.2s;
    pointer-events: none;
}

.combo-display.show {
    opacity: 1;
    animation: comboPulse 0.3s ease-out;
}

@keyframes comboPulse {
    0% { transform: scale(1.5); }
    100% { transform: scale(1); }
}

@media (max-width: 440px) {
    .title {
        font-size: 16px;
    }
    .score-board {
        gap: 20px;
        font-size: 10px;
    }
    .score-value {
        font-size: 14px;
    }
    .btn {
        font-size: 8px;
        padding: 10px 15px;
    }
    .instructions {
        font-size: 7px;
    }
}