.img-zh {
  background-image: url("../static/chinese-active.png");
  width: 16px;
  height: 16px;
}
.img-en {
  background-image: url("../static/english.png");
  width: 16px;
  height: 16px;
}
.btn:hover {
  background: #1B6C9C;
  color: #FFFFFF;
  .img-en {
    background-image: url("../static/english-active.png");
    width: 16px;
    height: 16px;
  }
}
.left-div{
  width: 468px;
  height: 100%
}
.title{
  display: flex;
  align-items: center;
  justify-content: flex-start;
  height: 116px;
  img {
    width: 80px;
    height: 80px;
    margin-right: 30px;
  }
  span {
    display: inline-block;
    font-family: Source Han Sans;
    font-size: 80px;
    font-weight: bold;
    line-height: normal;
    letter-spacing: 0.08em;
    font-variation-settings: "opsz" auto;
    font-feature-settings: "kern" on;
  }
  .first {
    color: #53882C;
  }
  .second {
    color: #9DC92A;
  }
}
.subTitle {
  width: 468px;
  height: 93px;
  font-family: Source Han Sans;
  font-size: 64px;
  font-weight: bold;
  line-height: normal;
  letter-spacing: 0em;
  font-variation-settings: "opsz" auto;
  font-feature-settings: "kern" on;
  color: #265B7B;
  margin-top: 25px; 
}
.line{
  width: 32px;
  height: 4px;
  opacity: 1;
  background: rgba(108, 109, 102, 0.7);
  /* // margin: 73px 0px 46px 0px; */
  margin: 69px 0px 58px 6px;
}
.slogan {
  display: flex;
  font-family: RTWS YaYuan G0v1;
  font-size: 42px;
  font-weight: normal;
  line-height: normal;
  letter-spacing: 0.12em;
  font-variation-settings: "opsz" auto;
  margin-left: 6px;
  span:first-child {
    color: #265B7B;
  }
  span:nth-child(2) {
    display: inline-block;
    width: 20px;
    height: 29px;
    margin: -12px 6.11px 0 2px;
  }
  .rotate-sup {
    display: inline-block;
    color: #E46E2F;
    font-size: 26px;
    transform: rotateZ(12.38deg);
    transform-origin: bottom left;
  }
  span:last-child {
    color: #9DC92A;
  }
}
.formula {
  height: 35px;
  font-family: Source Han Sans;
  font-size: 24px;
  font-weight: normal;
  line-height: normal;
  letter-spacing: 0.2em;
  font-variation-settings: "opsz" auto;
  font-feature-settings: "kern" on;
  color: #333333;
  margin-top: 21px; 
  margin-left: 6px;
  sup {
    font-size: 14px;
  }
  span:last-child {
    margin-left: -4px;
  }
}