Horizontal menu on Posts page??

Please help! When I set my blog page (www.sunbirdmedia.com/blog) as the “Posts” page under Settings>Reading, I can’t code anything for that page — I want to standardize all my pages to have a horizontal navigation bar along the top, which no problem with the static pages, but is there any way to do this for my posts page as well? As soon as I take away the “Posts” designation for my Blog page, the menu appears. Any advice?