iframe { width: 625px; height: 846px; border: 1px solid red; }

p.buttons { height: 3em; }
p.buttons span { display: block; width: 166px; height: 30px; background:url("gfx/button-facebook-bg.gif") 0% 0% no-repeat #fff; }
p.buttons span a { display: block; width: 162px; height: 27px; line-height: 27px; }
p.buttons span a:link, p.buttons span a:visited { color: #fff; background:url("gfx/button-facebook.gif") 0% 0% no-repeat #E9005C; }
p.buttons span a:active, p.buttons span a:hover { color: #fff; background:url("gfx/button-facebook.gif") 0% 0% no-repeat #B9003D; }
p.buttons span a span { display: block; width: 162px; height: 27px; line-height: 27px; position: absolute; top: 0; left: 0; }