document.getElementsByClassName = function(cl) {
		var retnode = [];
		var myclass = new RegExp('\\b'+cl+'\\b');
		var elem = this.getElementsByTagName('*');

		for (var i = 0; i < elem.length; i++) {
			var classes = elem[i].className;
			if (myclass.test(classes)) retnode.push(elem[i]);
		}

		return retnode;
	 };

	 var div_box_azzurro = new Array();
	 div_box_azzurro = document.getElementsByClassName('box_offerta_azzurro');
	 var div_box_giallo = new Array();
	 div_box_giallo = document.getElementsByClassName('box_offerta_giallo');
	 var div_box_arancio = new Array();
	 div_box_arancio = document.getElementsByClassName('box_offerta_arancio');
	 


	 for (i = 0; i < div_box_azzurro.length; i++) {
	 	div_box_azzurro[i].style.height='280px';
	 }

	 for (i = 0; i < div_box_giallo.length; i++) {
	 	div_box_giallo[i].style.height='280px';
	 }

	 for (i = 0; i < div_box_arancio.length; i++) {
	 	div_box_arancio[i].style.height='280px';
	 }