TopStyle is the premier CSS/HTML/XHTML editor that contains powerful tools for creating standards-compliant sites. It allows you to edit your HTML documents and style sheets using one interface. With it you can generate XHTML-compliant markup with a simple toggle. It also help you to validate your style sheets against multiple browsers, flagging any invalid properties or values it finds. Due its rich features, you may find it essential even if you have already had a html editor.