(function () {
	var arr = [
		'home',
		'service',
		'iis',
		'exchange',
		'sharepoint',
		'support'
	];
	
	var len        = arr.length
	var URL        = location.href;
	var a          = URL.split('/');
	var dir        = a[3];
	var currentNum;
	var list       = $('main-nav');
	var elm        = list.getElementsByTagName('li');
	
	if(a.length <= 4){
		currentNum = 0;
	}else{
		for (var i=0; i<len; i++){
			if (dir == arr[i]){
				currentNum = i;
			}
		}
	}
	
	if(currentNum != undefined){
		var target  = elm[currentNum].getElementsByTagName('a')[0];
		target.style.background = 'none';
	}
	
})();