.iframe_container {
 position: relative;
 overflow: auto;
 width: 100%;
 padding-top: 100%;
}

/* Then style the iframe to fit in the container div with full height and width */
.iframe_responsive {
 position: absolute;
 border: 0px;
 top: 0;
 left: 0;
 bottom: 0;
 right: 0;
 width: 100%;
 height: 100%;
}