The Bones theme framework comes with two different "styles" stylesheets. The default is parsed by Less and is called "styles.css". There is another stylesheet called styles-old.css that is traditional CSS file.
According to the the Bones Support section here is the solution:
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Copied from
http://themble.com/huge-responsive-bones-update/
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NO! I don’t like change! I want it the old way!
No worries, inside the library/css folder, there’s a file called old-css.css which contains the old css file. Just reference it in the header and you’re good to go. You’ll also want to call the respond.js file inside library/js/libs/ folder so that IE won’t be left out.
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