.access_map-block_iframe {
  position: relative;
  width: 640px;
  margin-left: auto;
  margin-right: auto;
  padding-bottom: 36.25%;
  height: 0;
  overflow: hidden;
}

.access_map-block_iframe iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

@media only screen and (max-width: 640px) {
  .access_map-block_iframe {
    width: 100%;
    padding-bottom: 96.25%;
  }
}