#videos a {
  display: block;
  width: 25%;
  margin-bottom: 20px;
  box-sizing: border-box;
  padding: 0 10px;
  float: left;
  cursor: pointer;
  text-decoration: none;
  outline: 0;
}

#videos a:hover {
  opacity: 0.7;
}

#videos a img {
  width: 100%;
  height: auto;
}

#overlay {
  background: rgba(0,0,0,0.8);
  position:fixed;
  top: 0;
  right: 0;
  left:0;
  bottom: 0;
  width: 100%;
  height: 100%;
  z-index: 99999;
  display: none;
}

#overlay .modal {
  background: #fff;
  border-radius: 5px;
  width: 90%;
  margin: 40px auto;
  max-width: 800px;
  min-height: 100px;
  position: relative;
  padding: 30px 20px 15px;
}

#overlay .modal #close {
  position: absolute;
  top: 5px;
  right: 5px;
  cursor: pointer;
}

#overlay iframe {
    width: 100%;
    height: 300px;
}