body {
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background-color: #111; /* 深夜模式背景 */
}

#game-container {
    position: relative;
    width: 800px;
    height: 600px;
    border: 1px solid #333;
    background-color: #222;
}

#circle {
    position: absolute;
    width: 40px; /* 圆形直径放大为 40px */
    height: 40px;
    border-radius: 50%;
    background-color: blue;
}

.square {
    position: absolute;
    width: 20px;
    height: 20px;
    background-color: red;
}

#timer {
    position: absolute;
    top: 10px;
    left: 10px;
    color: white;
}

#level {
    position: absolute;
    top: 10px;
    right: 10px;
    color: white;
}

#congratulations {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 36px;
    color: green;
    z-index: 10;
}