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

body {
    /* 這一行的背景改由程式去設定 */
    /* background-image: url(images/1.jpg); */
    background-size:auto;
    height: 100vh;
    width: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: "Montserrat";
    transition: background-image 1s ease-in-out;
}

.container {
    text-align: center;
    font-size: 24px;
}

select {
    font-size: 24px;
    margin-right: 20px;
}

h1 {
    font-size: 90px;
}

/*class="line" 的作用是讓每個 div 上下分開而且置中*/
.line {
    /* Adjust as needed */
    margin-bottom: 30px;
}

/* button */
.btnClass {
    font-weight: bold;
    font-size: 20px;
    background: #0074d9;
    color: white;
    padding: 12px 30px;
    border: none;
    border-radius: 30px;
    transition: 0.4s;
}

/* button */
.btnClass:hover {
    transform: scale(1.3);
    cursor: pointer;
}

#startBtn {
    display: block;
}

#stopBtn {
    display: none;
}

.textClass {
    background: #eaeef3;
    padding: 12px 30px;
    border: none;
    border-radius: 30px;
    opacity: 0.8;
}