function colors (element,clasa) {

while (element.tagName.toUpperCase() != 'TR' && element != null) {
      element = document.all ? element.parentElement : element.parentNode;
    //element.className = newClassName;
    }

     if (element.className=='silver' || element.className=='Checked') {
     //clasa='silver';
     }
     else {
       element.className = clasa;
     }

}




<!--
function HR (element,clasa) {
 // newClassName="unChecked"


  while (element.tagName.toUpperCase() != 'TR' && element != null) {

  element = document.all ? element.parentElement : element.parentNode;



  //element.className = newClassName;
  }

   if (element.className=='Checked') {
   element.className = clasa;
   }
   else {
   element.className = 'Checked';
   }
}




var ty = true;
var ara = new Array('plava1','plava2');
var m=0;
function CA (element){
m=0;

   for (var i=0;i<document.sub.elements.length;i++)
  {
       var e = document.sub.elements[i];

        e.checked = ty;



        if (!ty) {
          HR(e,ara[m]);
          //alert(i + " ---- " +ara[i]);
        m++;
        if (m==2) {
          m=0;
        }
        }
        else {
          HR(e,'Checked');
        }
  }
  if (ty) {
    ty=false;
  }
  else {
    ty=true;
  }
}
//-->

staro = new Object();
var starabarva="";
var fre = 1;
function kliknivSivo (element,clasa){

if (fre==2) {

HR2(staro,starabarva);
}



  HR2(element,'silver');

if (fre==1) {
fre=2;
}

if (staro!=element) {
staro=element;
starabarva="plava1";

}



}


function UNcheckAll (element,clasa){
m=0;

   for (var i=0;i<document.sub.elements.length;i++)
  {
       var e = document.sub.elements[i];
          HR2(e,ara[m]);
        m++;
        if (m==2) {
          m=0;
        }

  }
  HR2(element,'silver');

}


function HR2 (element,clasa) {
  while (element.tagName.toUpperCase() != 'TR' && element != null) {

  element = document.all ? element.parentElement : element.parentNode;



  //element.className = newClassName;
  }
if (element.className != 'Checked') {


element.className = clasa;
}
}