Home Tab Customization

Do not edit the Twenty Thirteen theme. It is the current default WordPress theme and having access to an original, unedited, copy of the theme is vital in many situations. First create a child theme for your changes. Or install a custom CSS plugin.

What does that have to do with my question?

Everything. You should not be editing the current default WordPress theme. Port your changes over to a child theme & re-upload a fresh, unpacked, copy of the Twenty Thirteen folder to wp-content/themes using FTP or whatever file management application your host provides.
http://ww.wp.xz.cn/themes/twentythirteen

Then activate your new child theme.