# EPUBCheck RSC-013: Fragment identifier is used in a…

Source: https://epublab.com/epubcheck/rsc-013/ (updated 2026-11-03)

EPUBCheck RSC-013 is a usage message: “Fragment identifier is used in a reference to a stylesheet resource.” A reference to a stylesheet includes a fragment identifier (#…), which has no meaning for CSS files.

- Official message (EPUBCheck 5.4.0): Fragment identifier is used in a reference to a stylesheet resource.
- Default severity: Usage

## Typical causes

- A link element with an href such as style.css#main.

## How to fix it

- Remove the #fragment from the stylesheet reference.

Message text and severity: EPUBCheck (W3C, BSD-3-Clause). Explanation: EPUBLab.