body {
    font-family: sans-serif;
    background-color: #f0f0f0;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0;
}

#game-wrapper {
    position: relative; /* ゲームオーバー画面を重ねるため */
}

canvas {
    background-color: #fff;
    border: 1px solid #ccc;
    cursor: none; /* マウスカーソルを非表示にする */
    display: block; /* canvas下の余白を消す */
}

#gameOverScreen {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.7);
    color: white;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

#gameOverScreen.hidden {
    display: none;
}

.ui-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 800px;
    padding: 10px;
    box-sizing: border-box;
}