# EPUBCheck CSS-006: CSS fixed positioning, how to fix it

Source: https://epubcc.com/epubcheck/css-006/ (updated 2026-11-04)

EPUBCheck CSS-006 is a usage message: “CSS selector specifies fixed position.” A CSS rule uses position: fixed, which reading apps handle inconsistently in paginated text. It is a usage note, not an error: the element may stay on screen, disappear or overlap the text depending on the app.

- Official message (EPUBCheck 5.4.0): CSS selector specifies fixed position.
- Default severity: Usage

## Typical causes

- Styles copied from a website, such as fixed headers, footers or navigation bars.
- Fixed positioning used to place a page number or logo on every screen.

## How to fix it

1. Open the file EPUBCheck names (the message gives the path, line and column) in a text or EPUB editor such as Sigil, or unzip the EPUB and open it there.
2. Remove position: fixed or replace it with normal flow (position: static or relative).
3. If the element was web navigation, remove it from the book: reading apps provide their own.
4. Rebuild the EPUB and run EPUBCheck again to confirm the message is gone.

## When it's not this

If the property is direction or unicode-bidi, it is forbidden outright and reported as CSS-001.

## Sources

- EPUBCheck 5.4.0 message texts (MessageBundle.properties, w3c/epubcheck on GitHub): https://github.com/w3c/epubcheck/blob/v5.4.0/src/main/resources/com/adobe/epubcheck/messages/MessageBundle.properties (read 2026-11-04)

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