I presume that your problem with background-image
is that it would be inefficient with a source for each image inside a stylesheet. My suggestion is to set the source inline:
<div style = 'background-image: url(image.gif)'></div>
div {
background-repeat: no-repeat;
background-position: 50%;
border-radius: 50%;
width: 100px;
height: 100px;
}