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

body {
    background: #000;
    min-height: 100vh;
    display: flex;
    justify-content: center;
    align-items: center;
    font-family: 'Courier New', monospace;
    overflow: hidden;
}

#game-container {
    position: relative;
    border-radius: 4px;
    overflow: hidden;
    box-shadow: 0 0 50px rgba(0, 255, 0, 0.3);
}

#gameCanvas {
    display: block;
    cursor: none;
}

#ui {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    padding: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    pointer-events: none;
}

#score {
    font-size: 32px;
    font-weight: bold;
    color: #0f0;
    text-shadow: 0 0 10px #0f0;
    letter-spacing: 5px;
}

#player-score {
    color: #0ff;
    text-shadow: 0 0 10px #0ff;
}

#cpu-score {
    color: #f00;
    text-shadow: 0 0 10px #f00;
}

#level {
    font-size: 18px;
    color: #0f0;
    text-shadow: 0 0 10px #0f0;
}

#message {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 24px;
    color: #0f0;
    text-shadow: 0 0 20px #0f0;
    text-align: center;
}

#start-screen {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.9);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    color: #0f0;
    text-shadow: 0 0 10px #0f0;
}

#start-screen h1 {
    font-size: 64px;
    margin-bottom: 40px;
    letter-spacing: 15px;
    animation: glow 2s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        text-shadow: 0 0 10px #0f0, 0 0 20px #0f0, 0 0 30px #0f0;
    }
    to {
        text-shadow: 0 0 20px #0f0, 0 0 40px #0f0, 0 0 60px #0f0, 0 0 80px #0f0;
    }
}

#start-screen p {
    font-size: 18px;
    margin-bottom: 15px;
    color: #0a0;
}

#start-screen .highlight {
    color: #0ff;
    text-shadow: 0 0 10px #0ff;
}

#start-screen .start-prompt {
    margin-top: 40px;
    font-size: 24px;
    animation: blink 1s ease-in-out infinite;
}

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

#start-screen.hidden {
    display: none;
}