var currentArticle = 1;

function changeArticle( n )
{
	if( n != currentArticle )
	{
		Element.addClassName( $('art_' + currentArticle), 'hd' );
		Element.removeClassName( $('art_but_' + currentArticle), 'active' );
		currentArticle = n;
		Element.removeClassName( $('art_' + currentArticle), 'hd' );
	}
}