Respond.js: No Comments Necessary
April 2020 note: Hi! Just a quick note to say that this post is pretty old, and might contain outdated advice or links. We're keeping it online, but recommend that you check newer posts to see if there's a better approach.
Earlier this year, Filament’s Scott Jehl released Respond.js, a small and fast script that brings CSS3 Media Query support to browsers like Internet Explorer 6-8, allowing you to build cross-browser Responsive Designs. As of last week, Respond.js no longer requires that you add the CSS comments it formerly needed to properly parse the media queries in your CSS — all you need to do is include the script and write CSS as you normally would. Added bonus: it’s 85% faster in IE!