#header header {
    font-size: 60%;
}

.videoWrapper {
  position: relative;
  overflow: hidden;
  width: 100%;
  padding-top: 100%; /* 16:9 Aspect Ratio (divide 9 by 16 = 0.5625) */
}

.videoWrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

sup {
    color: blue;
    cursor: help;
}