function hideDiv(){
hidearea = document.getElementById("hidvid");
tag = hidearea.getElementsByTagName("div");
for(x=0;x<tag.length; x++){
tag[x].style.display = "none";
}
tag = document.getElementsByName("but");
for(x=0;x<tag.length; x++){
tag[x].style.background = "transparent";
}
}
function navbut(id){
var ge=document.getElementById(id);
var gebut=document.getElementById(id + 'but');
hideDiv();
ge.style.display = "block";
gebut.style.background = '#CDBD92';
}

function addLoadEvent(func) {
var oldonload = window.onload;
if (typeof window.onload != 'function') {
window.onload = func;
} else {
window.onload = function() {
if (oldonload) {oldonload();}
func();
}
}
}
addLoadEvent(function() {
hidearea = document.getElementById("hidvid");
tag = hidearea.getElementsByTagName("div");
for(x=0;x<tag.length; x++){
tag[x].style.display = "none";
document.getElementById('part1').style.display = "block";}
tag = document.getElementsByName("but");
for(x=0;x<tag.length; x++){
tag[x].style.background = "transparent";
document.getElementById('part1but').style.background = "#CDBD92";
}
});