html,body{
  background-color: #F7F8FF;
  width: 100vw;
}

.upgrade-img-box{
  height: calc(100vh - 172px);
  margin: 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
  max-width: 1920px;
}

.upgrade-img ,.upgrade-phone-img{
  width: 100%;
  height: auto;
}

.footer {
  width: 100%;
  height: 162px;
  padding-top: 20px;
  position: relative;
  z-index: 1;
  
}

.footer ul {
  width: 100vw;
  line-height: 28px;
  margin: 0 auto;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 14px;
  font-family: MicrosoftYaHei;
  font-weight: 400;
  color: #999999;
  flex-wrap: wrap;
  padding: 0 10px;
}

.footer li:nth-child(2n) {
  width: 2px;
  height: 12px;
  border: 1px solid #979797;
  margin: 0 10px;
}

.footer li.li-hover,.footer-img>img{
  cursor: pointer;
}

.footer li.li-hover:hover{
  color: #ec3c14;
}

.footer-img{
  width: 100%;
  margin: 0 auto;
  padding:  20px;
  display: flex;
  justify-content: center;
}

.footer-img1{
  width: 52px;
  height: 52px;
}

.footer-img2{
  width: 136px;
  height: 50px;
  margin: 0 10px;
}

.footer-img3{
  width: 134px;
  height: 47px;
}