.imagewrapper a img {
border: none;
}

.imagewrapper {
position: relative;
float: left;
}

.imagewrapper span {
position: absolute;
z-index: 2;
height: 6px;
width: 6px;
}

.curve1 {
background: transparent url(images/img-tr.gif) top right no-repeat;
top: 0;
right: 0;
}

.curve2 {
background: transparent url(images/img-tl.gif) top left no-repeat;
top: 0;
left: 0;
}

.curve3 {
background: transparent url(images/img-br.gif) bottom right no-repeat;
bottom: 0;
right: 0;
}

.curve4 {
background: transparent url(images/img-bl.gif) bottom left no-repeat;
bottom: 0;
left: 0;
}