#overlay    {  background:rgba(255,0,0,1);
               text-align:center;
               padding:115px 0px;
               opacity:0;
    color: #fff;
               -webkit-transition: opacity .25s ease;
-moz-transition: opacity .25s ease;
position: absolute;
z-index: 1000;
width: 100%;
height: 100%;
}

.og-grid li a:hover #overlay {
               opacity:1;}