body {
  background-color: lightgrey;
  width: 100vw;
  display: flex;
  justify-content: center;
  position: relative;
}

.zoomSpace {
  width: 1000px;
  min-height: 500px;
}


/* 移到最上方按鈕 */
.back-to-top {
  position: fixed;
  bottom: 20px;
  right: 20px;
  background-color: #007bff;
  color: white;
  padding: 10px 15px;
  border-radius: 50%;
  text-align: center;
  cursor: pointer;
  box-shadow: 0px 0px 10px rgba(0, 0, 0, 0.1);
  display: none;
  font-weight: 900px;
  /* 初始隱藏按鈕 */
}

.back-to-top:hover {
  background-color: #0056b3;
}

.footer {
  margin-top: 10px;
}

@media screen and (max-width: 500px) {
  .zoomSpace {
    min-height: 500px;
  }
}