Twenty Thirteen - Enqueued styles in wp-admin

[Clorith]

Twenty Thirteen adds some nifty looking features with it's CSS, unfortunately these bleed into wp-admin (stylings such as input[type="submit"]) which can mess with plugins and other components.

Adding an is_admin() check to the enqueue function fixes this up nicely

[nacin]

Not sure what is going on in maybe a child theme, but twentythirteen_scripts_styles() is only triggered on the 'wp_enqueue_scripts' hook, which is only run on the frontend.