div {
width: 150px;
height: 150px;
background-color: #fff;
box-shadow: 120px 80px 40px 20px #0ff;
/* in order: x offset, y offset, blur size, spread size, color */
/* blur size and spread size are optional (they default to 0) */
}
element {
box-shadow:none;
}
element:hover, element:active {
box-shadow: inset 0 0 10px #(color of the glow you want);
}