Modify Chrome user agent stylesheet [duplicate]

For Chrome v32 and below:

  1. In Google Chrome, go to URL about:version and take note of the "profile path".
  2. Browse to the profile path in your file browser. Inside your profile folder, open the User StyleSheets folder. Inside "User StyleSheets", there should be a file called Custom.css, empty by default.
  3. Just add your styles in Custom.css.