.recommend {
  display: -webkit-box;
  display: -ms-flexbox;
  display: flex;
  -webkit-box-align: center;
  -ms-flex-align: center;
  align-items: center;
  position: relative;
  width: 80%;
  max-width: 1200px;
  margin: 0px auto;
  min-height: calc(100vh - 280px);
}

.recommend .videobox {
  position: relative;
  width: 100%;
  height: 0;
  margin: 50px auto;
  padding-bottom: 56.25%;
}

.recommend .videobox iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}