CSS
html, body { height: 100%; padding: 0; margin: 0;}
body {
/* Mozilla Firefox */
background-image: -moz-linear-gradient(top, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%), -moz-linear-gradient(bottom, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%);
/* Opera */
background-image: -o-linear-gradient(top, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%), -o-linear-gradient(bottom, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%);
/* Webkit (Safari/Chrome 10) */
background-image: -webkit-gradient(linear, left top, left bottom, color-stop(0, rgba(255, 255, 255, 0)), color-stop(0.5, rgba(255, 255, 255, 0)), color-stop(0.75, rgba(255, 255, 255, 0)), color-stop(1, #A3EF69)), -webkit-gradient(linear, left bottom, left top, color-stop(0, rgba(255, 255, 255, 0)), color-stop(0.5, rgba(255, 255, 255, 0)), color-stop(0.75, rgba(255, 255, 255, 0)), color-stop(1, #A3EF69));
/* Webkit (Chrome 11+) */
background-image: -webkit-linear-gradient(top, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%), -webkit-linear-gradient(bottom, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%);
/* W3C Markup, IE10 Release Preview */
background-image: linear-gradient(top, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%), linear-gradient(bottom, rgba(255, 255, 255, 0) 0%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0) 75%, #A3EF69 100%);
}