.aside_video {
  display: inline-block;
  width: 50vh;
  height: 100vh;
  position: absolute;
  top: 0;
  left: 5vh;
}

.aside_video iframe {
  width: 50vh;
  height: calc(50vh / 16 * 9);
  border: none;
  margin: calc(50vh - calc(50vh / 16 * 9 / 2)) 0;
  border-radius: 1vh;
}

@media screen and (max-width: 100vh) {
  .aside_video {
    width: 50vh;
    height: calc(50vh / 16 * 9);
    position: inherit;
    margin: calc(50% - 25vh);
  }

  .aside_video iframe {
    width: 50vh;
    height: calc(50vh / 16 * 9);
    margin: 0;
  }
}