How could I wrap a border around another border and have them both use inset drop-shadows (like double matting in a picture frame)?
You can accomplish this using the :before
and :after
pseudo-elements. See jsFiddle demos at end of answer.
<div class="frame"><img src="../img/logo.png"></div>
.frame {
display:inline-block;
position:relative;
margin:20px;
z-index:5;
padding:10px;
background:#376b90;
}
.frame:before {
position:absolute;
content:".";
display:block;
font-size:0;
color:transparent;
/* Change left, right, top, bottom, and box-shadow to position */
left:0;
top:0;
right:0;
bottom:0;
box-shadow:inset 0 0 3px 2px black;
}
.frame:after {
position:absolute;
content:".";
display:block;
font-size:0;
color:transparent;
/* Change left, right, top, bottom, and box-shadow to position */
left:5px;
top:5px;
right:5px;
bottom:5px;
box-shadow:inset 0 0 3px 2px black;
}