.rounded {
 position: relative;
 padding: 5px 0;
}

.tl, .tr, .bl, .br {
 position: absolute;
 height: 5px;
 width: 5px;
 background-repeat: no-repeat;
}
.tt, .bb {
 position: absolute;
 height: 5px;
 width: 790px;
 left: 5px;
 right: 5px;
}

.tl {
 background-position: top left;
 top: 0;
 left: 0;
}
.tt { top: 0;}
.tr {
 background-position: top right;
 top: 0;
 right: 0;
}
.bl {
 background-position: bottom left;
 bottom: 0;
 left: 0;
}
.bb { bottom: 0;}
.br {
 background-position: bottom right;
 bottom: 0;
 right: 0;
}