Rozbalovací menu

function rozvin(idecko)
{
var id = parseInt(idecko);
var  odkaz = document.getElementById(id + "odkaz");
odkaz.className= "active";
var div = document.getElementById(idecko);
var elem = div.firstChild;
var v = document.defaultView.getComputedStyle(elem,"").height;
if(elem.style.display = "none")
{
elem.style.display = "";
}
v = parseInt(v);
if(elem.style.visibility == "hidden")
{
elem.style.height = "0px";
elem.style.visibility = "visible";
elem.timeout = window.setInterval(function(){rolout(elem, v)}, 20);
}
}

function rolout(elem, v)
{
var c = document.defaultView.getComputedStyle(elem,"").height
c = parseInt(c);
d = c;
if(d < v/5)
{
d = v/5;
}
var plus = v - d;
plus = Math.sqrt(plus);
plus = parseInt(plus);

if(c == 0)
{
elem.style.height = "20px";
}
else
{
elem.style.height = c + plus + "px";
}
if(c >= v)
{
clearInterval(elem.timeout);
d = 0;
c = 0;
plus = 0;
}
}

function svin(idecko){

var div = document.getElementById(idecko);
var elem = div.firstChild;
//window.alert(elem.timeout);
var v = document.defaultView.getComputedStyle(elem,"").height;
v = parseInt(v);
elem.t = setInterval(function(){rollin(elem, v)}, 15);
var id = parseInt(idecko);
var  odkaz = document.getElementById(id + "odkaz");
odkaz.className= "";

}

function rollin(elem, v)
{
var c = document.defaultView.getComputedStyle(elem,"").height;
c = parseInt(c);
var d = c;
if(d > v/5)
{
d = v/2 + v/3;
}
var plus = v - d;
//plus = Math.sqrt(plus);
plus = parseInt(plus);

if(c < 20 || plus > c)
{
clearInterval(elem.t);
elem.style.height = v + "px";
elem.style.visibility = "hidden";
elem.style.overflow="hidden";
d = 0;
c = 0;
plus = 0;
}
else if(c != 0)
{
elem.style.height = c - plus + "px";
}
}

<div class="podmenu"><ul><li id="2odkaz"  onMouseOver="rozvin('2roleta');">
<a  onMouseOut="svin('2roleta');" //tohle jsem zkoušel dát všude možně ale pořád mi to nefunguje//
  href='http://hydrotechnik.vyvoj.investck.cz/hydrotechnik_info/o_spolecnosti/'>O společnosti</a><div id="2roleta" class="podpodmenu"><ul style="overflow:hidden; visibility:hidden;"><li class="zakulaceni_horni"></li><li class="zakulaceni_dolni"></li></ul></div>