Marked: Overriding Styles

The GitHub style bundled with Marked is pretty good, but I prefer to substitute a couple fonts and remove the outer border. Here's how I modify the built-in stylesheet without duplicating the whole CSS file:

/*
   Title: GitHub Modified
   Author: Annika Backstrom
   Description: Additional styles for Marked's GitHub style.

   Save this file to ~/Library/Application Support/Marked/Custom CSS
*/

@import url("/Applications/Marked.app/Contents/Resources/github.css");

body {
    font-family: Open Sans;
}

tt, code {
    font-family: Inconsolata;
    font-size: 14px;
}

#wrapper {
    box-shadow: none;
    padding: 15px;
}