function Black(){


if( document.getElementById('Black') ){
		
                document.getElementById('Black').id='White';
		document.getElementById('nombre_color').innerHTML = 'Cambiar a negro';
                document.cookie='color=White; expires=Thu, 2 Aug 2111 23:59:59 UTC; path=/';
				



                
}else{
		  
                document.getElementById('White').id='Black';
		document.getElementById('nombre_color').innerHTML = 'Cambiar a blanco';
                document.cookie='color=Black; expires=Thu, 2 Aug 2111 23:59:59 UTC; path=/';
               
}       
	
	

}