var num=1
function columns(){
	var pantalla=document.body.clientHeight-document.getElementById('header').offsetHeight;
	var page=document.getElementById('columna_dreta').offsetHeight;
	var colE=document.getElementById('columna_esquerra')
	var colC=document.getElementById('columna_centre')
	var colU=document.getElementById('columna_unica')
	if(colE==null){
		if(colU.offsetHeight<page){
			colU.style.height=page+'px'
		}
	}else{
		if(colE.offsetHeight<page){
			colE.style.height=colC.style.height=page+'px'
		}else{
			if(colE.offsetHeight<colC.offsetHeight){
				colE.style.height=colC.offsetHeight+'px'
			}else{
				colC.style.height=colE.offsetHeight+'px'
			}
			if (colE.offsetHeight<pantalla){
				colE.style.height=pantalla+'px'	
				colC.style.height=pantalla+'px'
			}
		}
	}
}
function borraContent(){
	cercador=document.getElementById('cercador')
	cercador.value=''
	cercador.style.color='#000000'
}
window.onresize=columns