Some styling not appearing in IE8

Hi, can anyone solve my problem. My site is basic in respect to xhtml but it uses a some jquery - however, all was fine. site is working fine in FF/Safari/Opera - but in IE8 a lot of the styles seemed to have gone by some way. i am not understanding what is happening........

You might have to use an HTML4.0 doctype and not an HTML5 one.
This will definitely works.......