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

body {
    background-color: #111;
    color: #fff;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    overflow: hidden;
    height: 100vh;
    width: 100vw;
}

canvas {
    display: block;
}

#ui {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

#score {
    position: absolute;
    top: 20px;
    left: 20px;
    font-size: 24px;
    font-weight: bold;
    opacity: 0.8;
}

#gameOver {
    background: rgba(0, 0, 0, 0.85);
    padding: 40px;
    border-radius: 12px;
    text-align: center;
    pointer-events: auto;
    backdrop-filter: blur(5px);
    border: 1px solid #333;
    box-shadow: 0 10px 30px rgba(0,0,0,0.5);
}

#gameOver.hidden {
    display: none;
}

#gameOver h1 {
    color: #ff4d4d;
    margin-bottom: 10px;
    font-size: 3em;
    text-transform: uppercase;
    letter-spacing: 2px;
}

#gameOver p {
    font-size: 1.5em;
    margin-bottom: 30px;
}

#restartBtn {
    background: #ff4d4d;
    color: white;
    border: none;
    padding: 12px 30px;
    font-size: 1.2em;
    border-radius: 30px;
    cursor: pointer;
    transition: transform 0.2s, background 0.2s;
    text-transform: uppercase;
    font-weight: bold;
}

#restartBtn:hover {
    background: #ff3333;
    transform: scale(1.05);
}

#restartBtn:active {
    transform: scale(0.95);
}