body{
    background-image:url(img/IMG_7126.JPG);
    background-attachment: fixed;        /* 背景固定 */
    background-size: cover;              /* 覆蓋整個畫面 */
    background-repeat: no-repeat;        /* 不重複 */
    background-position: center center;
}
.whitebox{
  width: 200px;
  height: 100px;
  background-color: transparent;
  border: 2px solid transparent;
  margin: 20px auto;
}
.first{
    margin: 20px auto;
    padding: 20px;
    max-width: 600px;
     background-color: rgba(0, 0, 0, 0.5);
    text-align: center;
    color: rgb(174, 231, 15);
    font-size: 24px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(255,255,255,0.2);
}
.second{
    margin: 20px auto;
    padding: 20px;
    max-width: 600px;
     background-color: rgba(0, 0, 0, 0.5);
    text-align: center;
    color: rgb(15, 231, 213);
    font-size: 24px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(255,255,255,0.2);
}