<style>
    div {
        border-width: 21px 30px 30px 21px;
        width: 75px;
        height: 75px;
        margin: 10px;
        border-image-source: url(resources/border-image.png);
        border-image-slice: 21 30 30 21 fill;
        border-image-width: 1;
        border-image-repeat: repeat;
    }
</style>
<div></div>
This should look like the above, only scaled up by a factor of 2:
<div style="zoom: 2;"></div>