.top-to-bottom {
    border-width: 1px;
    border-style: solid;
    -webkit-border-image: 
      -webkit-gradient(linear, 0 0, 0 100%, from(#E6E9E9), to(rgba(0, 0, 0, 0))) 1 50%;
    -webkit-border-image: 
      -webkit-linear-gradient(#E6E9E9, rgba(0, 0, 0, 0)) 1 50%;
    -moz-border-image:
      -moz-linear-gradient(#E6E9E9, rgba(0, 0, 0, 0)) 1 50%;    
    -o-border-image:
      -o-linear-gradient(#E6E9E9, rgba(0, 0, 0, 0)) 1 50%;
    border-image:
      linear-gradient(to bottom, #E6E9E9, rgba(0, 0, 0, 0)) 1 50%;
}

.top-border,
.bottom-border {
    border-top: 1px solid #E6E9E9;
}