_dom = document.all?(document.getElementById?2:1)
                   :(document.getElementById?4:(document.layers?3:0));

function getWinYOffset(){
  if(_dom==4)            return window.scrollY;
  if(_dom==2 || _dom==1) return document.body.scrollTop;
  if(_dom==3)            return window.pageYOffset;
  return 0;
}
var dist = 0;

function Scd(dist) {
for(var i = getWinYOffset(); i<dist;i += 3) { window.scroll(0,i) }
}

function Scu(dist) {
for(var i=getWinYOffset(); i>=dist;i -= 10) { window.scroll(0,i) }
}

function Sct(dist) {
for(var i=getWinYOffset(); i>=dist;i -= 5) { window.scroll(0,i) }
}