/* 回到顶部 */
.topBtn {
  position: fixed;
  bottom: 10%;
  right: 10%;
  z-index: 9;
  width: 40px;
}
/* 左侧导航栏 */
.menu {
  position: fixed;
  top: 40%;
  right:10px;
  z-index: 9;
  width: 50px;
  background-color: mintcream;
  opacity: 0.7;
  border-radius: 10px;
}
.menu > div {
  margin: 10px auto;
  width: 30px;
}
.menu > div:hover,
.topBtn:hover {
  cursor: pointer;
}

#content {
  margin: 0 auto;
  width: 90%;
  max-width: 1000px;
  background-color: mintcream;
  color: rgb(0, 0, 0);
  position: relative;
  z-index: 1;
  padding: 20px 10px;
}

.footer {
  padding: 50px 0 120px;
  text-align: center;
  color: rgb(110, 110, 110);
  font-weight: 600;
  font-size: 18px;
  width: 95%;
  margin: 0 auto;
}
img{
  max-width: 100%;
}