CSS: Position loading indicator in the center of the screen

Question

How can I position my loading indicator in the center of the screen. Currently I\'m using a little placeholder and it seems to work fine. However, when I scroll down, the loadin

Answer 1

.loader{
  position: fixed;
  left: 0px;
  top: 0px;
  width: 100%;
  height: 100%;
  z-index: 9999;
  background: url('//upload.wikimedia.org/wikipedia/commons/thumb/e/e5/Phi_fenomeni.gif/50px-Phi_fenomeni.gif') 
              50% 50% no-repeat rgb(249,249,249);
}