.wrap{
  margin-bottom: 1.5rem;
}
.youtube {
  position: relative;
  height: 0;
  margin-bottom: 20px;
  padding-bottom: 56.25%;
  overflow: hidden;
}
.youtube iframe {
  position: absolute;
  top: 0;
  right: 0;
  width: 100%;
  height: 100%;
}
.wrap img{
  width: 100%;
}
 
/* ココから下がPC表示（600px以上）のレイアウト */
@media screen and (min-width: 600px) {
  .float-right{
    float: right;
    width: 49.5%;
  }
  .float-left{
    float:left;
    width: 49.5%;
  }
  .wrap:after{
    display: block;
    clear: both;
    content: "";
  }
}