If you remove
height: 100% in your style.css and I don't remove it in theme style.css, next time you update the theme, it will be there again. And that's not good:)
@technguide: could you point out which browser that happened? And url where this happens. I can't replicate that issue in any of browsers that I'm testing.
You have this weird script before DOCTYPE. It doesn't come from the theme. I guess it's coming from a plugin.
//location = "/construction/";
What comes to Validators, use HTML5 DOCTYPE. And even after that Validators pick up a few 'errors'. Link is more like this. I don't think there are any bugs in theme template files, but please let me know if there are.
And I encourage you to install and activate child theme just in case you make even one modification.