:root {
    --bg-color: #050510;
    --letterbox-color: #000;
    --accent-color: #4ff;
    --text-color: #fff;
    --font-family: 'Courier New', Courier, monospace; /* Retro aesthetic */
}

body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    background-color: var(--letterbox-color);
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: var(--font-family);
    user-select: none;
}

#game-container {
    position: relative;
    width: 800px; /* Base size, updated by JS */
    height: 600px;
    background-color: var(--bg-color);
    box-shadow: 0 0 50px rgba(0, 20, 40, 0.5);
    overflow: hidden;
}

#game-canvas {
    display: block;
    width: 100%;
    height: 100%;
}

#ui-layer {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
}

#score {
    position: absolute;
    top: 20px;
    right: 30px;
    font-size: 3rem;
    font-weight: bold;
    color: rgba(255, 255, 255, 0.2);
    transition: transform 0.1s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

#score.bump {
    transform: scale(1.5);
    color: var(--accent-color);
}

#tutorial {
    position: absolute;
    bottom: 30px;
    width: 100%;
    text-align: center;
    font-size: 1.2rem;
    color: rgba(255, 255, 255, 0.3);
    letter-spacing: 2px;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.3; }
    50% { opacity: 0.6; }
}