function getElementsByClass(searchClass,node,tag) {
	var classElements = new Array();
	if ( node == null )
		node = document;
	if ( tag == null )
		tag = '*';
	var els = node.getElementsByTagName(tag);
	var elsLen = els.length;
	var pattern = new RegExp('(^|\\s)'+searchClass+'(\\s|$)');
	for (i = 0, j = 0; i < elsLen; i++) {
		if ( pattern.test(els[i].className) ) {
			classElements[j] = els[i];
			j++;
		}
	}
	return classElements;
}

function addArrowhead() {
	var getArrows = getElementsByClass("arrow");
	for(var i=0; i<getArrows.length; i++){
		var arrowBody = getArrows[i];
		var arrowHead = document.createElement("span");
		arrowHead.className = "arrowhead";
		arrowBody.appendChild(arrowHead);
	}
}

function fadeUp(element,red,green,blue) {
  if (element.fade) {
    clearTimeout(element.fade);
  }
  element.style.backgroundColor = "rgb("+red+","+green+","+blue+")";
  if (red == 255 && green == 255 && blue == 255) {
    return;
  }
  var newred = red + Math.ceil((255 - red)/10);
  var newgreen = green + Math.ceil((255 - green)/10);
  var newblue = blue + Math.ceil((255 - blue)/10);
  var repeat = function() {
    fadeUp(element,newred,newgreen,newblue)
  };
  element.fade = setTimeout(repeat,100);
}

function addLoadEvent(func) {
  var oldonload = window.onload;
  if (typeof window.onload != 'function') {
    window.onload = func;
  } else {
    window.onload = function() {
      oldonload();
      func();
    }
  }
}

addLoadEvent(addArrowhead);