.bg-center { background-repeat: no-repeat; background-position: center center; }
.bg-right  { background-repeat: no-repeat; background-position: center right; }
.bg-left   { background-repeat: no-repeat; background-position: center left; }
.bg-top    { background-repeat: no-repeat; background-position: center top; }
.bg-bottom { background-repeat: no-repeat; background-position: center bottom; }