h1 {
    color: red;
    text-align: center;
}

.center-text {
    text-align: center;
    color: green;
}

.end_comment {
    font-size: 24px;
    text-align: center;
    color: blue;
}

button {
    width: 250px;
    height: 50px;
    font-size: 18px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 10px;
    display: block;
    margin: 50px auto;  /* 上下50px、左右自動 */
}

button:hover {
    background-color: #45a049;
    transform: scale(1.1);
}