.back:hover{
  animation: rotation 2.5s infinite linear;
}

@keyframes rotation {
  0% {
    transform: rotate(-50deg);
  }
  50% {
    transform: rotate(50deg);
  }
  100% {
    transform: rotate(-50deg);
  }
}
body{
    background-image: url('https://ygdrzil.neocities.org/videos/tvbg.jpg');
    background-size: 1310px;
}
#Documentaries {
   width:720px;
   position:relative;
   margin-top:-220px;
   margin-left:90px;

  }
  .tvbutton {
      background:none;
      border:none;
      position:absolute;
      }


   #btv {
      margin-top:-680px;
      
      padding-left:790px;     
      }
     
  .tvbutton:active {
    filter: brightness(80%);
    }    
      
      
  .slides {
  display: none;
}    
      
  #docus {     
    margin-top:-695px;
    margin-left:235px;
    overflow:hidden;
    }
    

    
   #docus iframe {
      height:345px;
      width:460px;
      border-radius:50px;
     }