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

body {
    background: #000011;
    font-family: 'Courier New', monospace;
    color: #fff;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    overflow: hidden;
}

.game-container {
    text-align: center;
    position: relative;
}

.ui {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr 1fr;
    gap: 20px;
    padding: 10px 20px;
    background: rgba(0, 0, 0, 0.7);
    border-radius: 10px 10px 0 0;
    font-size: 16px;
    font-weight: bold;
    text-align: center;
}

#gameCanvas {
    border: 2px solid #333;
    background: linear-gradient(45deg, #000011, #001122);
    display: block;
}

.instructions {
    background: rgba(0, 0, 0, 0.8);
    padding: 15px;
    border-radius: 0 0 10px 10px;
    font-size: 14px;
    line-height: 1.5;
}

.instructions p {
    margin: 5px 0;
}

.score {
    color: #00ff88;
}

.health {
    color: #ff4444;
}

.level {
    color: #ffaa00;
}

.enemies {
    color: #88aaff;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.7; }
}

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