Edges are not displayed when viewed about page from mobile

Bug description

At least on the about page jolla theme seems to break off at the edges when viewed from smart phones.
This is also reproduced when using the desktop browser's developer tools.

In this image, the site as displayed with quarto preview and in the desktop version of Firefox.

website: https://www.rocker-project.org/
source: https://github.com/rocker-org/website/tree/47ccfc619fffaca5d8caac4db79edeee526e0e46

[✓] Checking Quarto installation......OK
      Version: 0.9.566
      Path: /opt/quarto/bin

[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....OK
      Version: 3.8.10
      Path: /usr/bin/python3
      Jupyter: 4.10.0
      Kernels: python3

[✓] Checking Jupyter engine render....OK

[✓] Checking R installation...........OK
      Version: 4.2.0
      Path: /usr/local/lib/R
      LibPaths:
        - /usr/local/lib/R/site-library
        - /usr/local/lib/R/library
      rmarkdown: 2.14

[✓] Checking Knitr engine render......OK

Checklist

• formatted your issue so it is easier for us to read?
• included a minimal, self-contained, and reproducible example?
• documented the quarto version you're running, by providing the output produced by quarto check in a terminal in your issue?
• documented the RStudio IDE version you're running (if applicable), by providing the value displayed in the "About RStudio" main menu dialog?
• documented which operating system you're running? If on Linux, please provide the specific distribution as well.
• upgraded to the latest version, including your versions of R, the RStudio IDE, and relevant R packages?

Start with the linked website source at commit 47ccfc619fffaca5d8caac4db79edeee526e0e46 and run quarto preview for the about page. Reproduce the Jolla theme clipping in a mobile viewport, locate the page or theme styling responsible, and verify that the page edges display correctly on mobile and desktop-browser emulation.