Class Properties
gl-bg-bottom
background-position: bottom;
gl-bg-center
background-position: center;
gl-bg-left
background-position: left;
gl-bg-left-bottom
background-position: left bottom;
gl-bg-left-top
background-position: left top;
gl-bg-right
background-position: right;
gl-bg-right-bottom
background-position: right bottom;
gl-bg-right-top
background-position: right top;
gl-bg-top
background-position: top;