var scrollPct, prevStep, nextStep, interStep
steps=new Array();steps[0]=new Array(0,102,153);steps[1]=new Array(255,0,0);steps[2]=new Array(255,255,0);steps[3]=new Array(0,255,0);steps[4]=new Array(0,255,255);steps[5]=new Array(0,0,255);steps[6]=new Array(255,0,255);steps[7]=new Array(255,0,0);
function newColor(chan) {var i=Math.floor(steps[prevStep][chan]+interStep*(steps[nextStep][chan]-steps[prevStep][chan]));return i;}
function scrollFunk() {scrollPct=(steps.length-1)*document.body.scrollTop/(document.body.scrollHeight-document.body.clientHeight);
prevStep=Math.floor(scrollPct);nextStep=Math.ceil(scrollPct);interStep=scrollPct-prevStep;
var newRGB="rgb("+newColor(0)+","+newColor(1)+","+newColor(2)+")";var invRGB="rgb("+(255-newColor(0))+","+(255-newColor(1))+","+(255-newColor(2))+")";
if (document.body.style.scrollbarTrackColor != null) {document.body.style.scrollbarFaceColor=newRGB;document.body.style.scrollbarTrackColor=invRGB;}}
window.onscroll=scrollFunk;