#mainscreen {
    position: relative;
    overflow: hidden;
    width: 100%;
    padding-top: 56.25%;
    border: 1px solid black;
    border-top: 0;
    background-image: url(https://img.youtube.com/vi/_3RVP9fcmJI/maxresdefault.jpg);
    background-size: cover;
  }

  #mainscreen iframe {
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    right: 0;
    width: 100%;
    height: 100%;
  }
 
  #controls {
    position: relative;
    width: 100%;
    border-top: 0;
    height: 61px;
    font-family: "Helvetica Neue", Helvetica, sans-serif;
    border: 1px solid black;
    border-top: 0;
  }

  #video{
      display: none;
  }

  #play{
    text-align: center;
    height: 60px;
    padding-top: 19px;
  }

  #stop{

  }

  #cams{
      display: none;
  }

  .cam {
    width: 25%;
    height: 60px;
    border-right: 1px solid black;
    cursor: pointer;
    text-align: center;
    padding-top: 19px;
    display: inline-block;
    vertical-align: top;
  }

  .cam:hover, #play:hover, #stop:hover{
    background-color: #EEEEEE;
    cursor: pointer;
  }

  #cam3 {
    border-right: 0;
  }

  .bi{
      font-size: 25px;
      padding-top: 0;
      margin-top: -5px;
      display: inline-block;
  }