Find design Problems (html,css)

i have some ASP.NET pages. pages does not appear in FireFox4 same IE9. i want to find my HTML or CSS Design problems. i 开发者_开发知识库hared that this is a tool for finding problems. but i can't use it because my ASP.NET Page contains some usercontrols. I am looking for a way to find my design problems(tool , tip , etc). another note is i am using jQuery UI plugins in my site.

One approach would be to use Chrome Developer Tools / Firebug / IE 8 Developer Tools to take a peek at the HTML being generated to look for any glaring errors. It can also help catch some jQuery issue that might be causing you grief.

Outside of that, HTML Tidy is a nice program that could help diagnose some stuff for you as well.

One thing to realize is that every browser renders a page slightly different, despite the attempts to render them in a "universal" manner. If you're really looking for the small differences, you can check out the SuperPreview tool that comes with Microsoft Expression Web