.iframe-container {
  overflow: hidden;
  padding-top: 100%;
  position: relative;
}
 
.iframe-container iframe {
   border: 0;
   height: 100%;
   left: 0;
   position: absolute;
   top: 0;
   width: 100%;
}
 
/* 4x3 Aspect Ratio */
.iframe-container-4x3 {
  padding-top: 100%;
}