You usually use padding to add distance between a border and a content.However, background are spread on padding.
You can still do it with nested element.
html :
<div id="outter">
<div id="inner">
test
</div>
</div>
outter div :
border-style: ridge;
border-color: #567498;
border-spacing:10px;
min-width: 100px;
min-height: 100px;
float:left;
inner div :
width: 100px;
min-height: 100px;
margin: 10px;
background-image: -webkit-gradient(
linear,
left bottom,
left top,
color-stop(0, rgb(39,54,73)),
color-stop(1, rgb(30,42,54))
);
background-image: -moz-linear-gradient(
center bottom,
rgb(39,54,73) 0%,
rgb(30,42,54) 100%
);}