// JavaScript Document


function dark(colnum){ 
	if(document.getElementsByTagName){  
		var table = document.getElementById('thetable');   
		var col = table.getElementsByTagName("td");   
		col[colnum].className = "effect"; 
	}
}

function light(colnum){ 
	if(document.getElementsByTagName){  
		var table = document.getElementById('thetable');   
		var col = table.getElementsByTagName("td");   
		col[colnum].className = "return"; 
	}
}