.theme-issuu {
  position: relative;
  width: 100%;
  padding-top: 56.25%; // 16 : 9
  height: 0;
  overflow: hidden;
  max-width: 100%;

  iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100% !important;
    height: 100% !important;
  }
}