a.glo{
 color:#ffffff;
 padding: 10px 20px;
 width:100px;
 text-decoration:none;
 text-align:center;
 margin:20px auto;
 background-image: linear-gradient(to left,transparent,transparent 50%,#00c6ff 50%,#00c6ff);
 background-position: 100% 0;
 background-size: 200% 100%;
 transition: all .25s ease-in;
 font: 400 20px;
 border: 2px solid #00C6FF;
}
a.glo:hover {
background-position: 0 0;
color:#fff;
}