a.placeholder {
		float:left; clear:both; 
		background-repeat:no-repeat;
		line-height:30px;
		cursor:pointer;
		text-decoration:none;
		}

	.lecture_dir
	{
		float:left;
		height:35px;
		line-height:30px;
		vertical-align:middle;
		margin-left: 10px;
		padding-left:35px;
		white-space: nowrap;
		
		background-image:url('/images/icon/folder.png');
		background-repeat:no-repeat;
		background-position:left center ;
		
		cursor:pointer;
		text-decoration:none;		
		
		font-weight:bold;
		
	}
	.lecture_dir:hover
	{
		text-decoration:none;	
	}

	.lecture_file
	{
		float:left;
		clear:both;
		height:35px;
	
		line-height:30px;
		vertical-align:middle;
		margin-left: 10px;
		padding-left:35px;
		white-space:nowrap;		
		cursor:pointer;		
		
		text-decoration:none;
		
		background-image:url('/images/icon/file.png');
		background-repeat:no-repeat;
		background-position:left center ;
		
	}
	
	.lecture_file:hover
	{
		text-decoration:underline;	
	}
	
	.a_resource_link
	{
		float:left;
		clear:both;
		line-height:30px;
		vertical-align:middle;
		margin:0px 5px 0px 5px;	
		color:#006699;
		cursor:pointer;
	}

	.a_resource_link:hover{
		text-decoration:underline;	
	}
	
	.div_link_emtpy
	{
		float:left;
		clear:both;
		line-height:30px;
		vertical-align:middle;
		margin:5px;	
		color:red;
	}