Hi all

I have a problem when I try set a image in "Disclosure", I know the procedure but many images only displays the silhouette

examples
p3.PNGp1.PNGp2.PNG
the "twitter" and "info" pictures displays only the silhouette, the three files are png, too I try with the same size and converting to base64 with this page http://www.dailycoding.com/Utils/Con...eToBase64.aspx with the same return

css code
Code:
.csldocuments .x-list-disclosure
{
    /*-webkit-mask: 0 0 url('images/Info.png') no-repeat; 
       -webkit-mask-box-image: url(''images/Info.png''); */
	-webkit-mask-box-image: url('data:image/png;base64,iVBO...mCC');
	width: 2em;
	height: 2em;
	-webkit-mask-size: 2em 2em;
}
Code:
SL.views.documentsList = new Ext.List({
	id: 'documentsList',
	store: documentsStore,
	grouped: true,
	disableSelection: true,
	cls: 'csldocuments',
	emptyText: 'The result for search has no data.',
        ...
});
I want to make a new image but I do not display correctly, what are the parameters that must be the image?


thank you in advance