#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: 100px 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%;
}