function clickHandler() { 
    var targetId, srcElement, targetElement;  
    srcElement = window.event.srcElement;  
    if (srcElement.className == "category") {
      targetId = srcElement.id + "submenu";
      targetElement = document.all(targetId);
      if (targetElement.style.display == "none") {
        targetElement.style.display = "block";     
      } else {
        targetElement.style.display = "none";
      }  
    }
  } 
  document.onclick = clickHandler; 

function show(name){
document.getElementById(name).style.display = "block";
}
function hide(name){
document.getElementById(name).style.display = "none";
}