28px top-spacing in html body problem of WordPress 3.1

Problem : Few month ago I fall a great problem of wodpress that 28px top-spacing in html body.I can not solved it by CSS and last I find a solve from WordPress forum,I hope it’s very important to know of WordPress developer how to solve it.The problem is seen like the screenshot :

Solution : This not a problem of WordPress if you don’t add the admin panel into the function file of wordpress you face this problem after logout from the admin panel you don’t show this extra space.Have a solution if you don’t show the admin panel after login add the below code into function.php file :

function my_function_admin_bar(){ return false; }
add_filter( 'show_admin_bar' , 'my_function_admin_bar');