.first{
  display:flex;
  justify-content:space-between;
  width:100%;
  height:777px;
  margin-top:44px;
}
.first-left{
  width:875px;
  height:100%;
  flex:none;
}
.first-left-top{
  width:100%;
  height:493px;
  flex:none;
}
.first-left-bottom{
  width:100%;
  height:270px;
  flex:none;
}
.first-left{
  display:flex;
  flex-direction:column;
  justify-content:space-between;
}

@media (max-width:1400px){
  .first-left{
    width:61.5vw;
  }
  .first-left-top{
    height:34.59vw;
  }
  .first{
    height:56vw;
    margin-top:3vw;
  }
}
@media (max-width:767px){
  .first{
    height:unset;
    margin-top:5vw;
    display:block;
  }
  .first-left{
    width:100vw;
  }
  .first-left-top{
    height:56.4vw;
  }
}