Designers play peek-a-boo at NY Fashion Week

Now you see fashion, now you don’t.

Illusion was one of the key trends to emerge as New York Fashion Week entered its fourth day Sunday, with sheer looks making a quiet statement.

Strategic use of sheer fabric — here on sleeves, there on a neckline, overlay or skirt — gave the illusion of bareness without revealing too much. The look was naturally sexy, without being vulgar.

The light, airy feel of the clothes went with a generally optimistic feeling that has prevailed at the spring 2011 previews at Mercedes-Benz Fashion Week.

Late Sunday, the crowd headed to a twenty-fifth anniversary party for Tommy Hilfiger, one of the splashiest events of the week.