Microsoft does not support IE8 anymore, and neither do we.
When using @media CSS queries, Internet Explorer 8 and below will fail to respect them.
Though there are several options (like mediatizr and css3-mediaqueries), 
  Respond.js
  
    Show archive.org snapshot
  
 was the only one that worked for me.
If you do not want to pollute your application's default JS file with Respond.js, simply:
- 
Create an extra JS file (like media_queries_polyfill.js) that loads Respond.js://= require respond-1.4.2
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Make sure it's added to config.assets.precompile
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Embed that JS file in your layout only for old IEs. Looks like this in Haml: /[if lt IE 9] = javascript_include_tag 'media_queries_polyfill'
Note: Using an IE conditional means other super-ancient browsers that do not support media queries (like Safari 2.x, or Firefox 3.0 and below) will still not respect them. You are probably fine with that.