dark mode toggle moves adjacent to title on small screens

Bug description

The dark mode toggle does not stay on the right side of the navbar on small screens.

Steps to reproduce

Given the Quarto project configuration:

project:
  title: project title
  type: website

website:
  navbar:
    pinned: true
    left:
      - text: "Home"
        href: index.qmd
  search: true

format:
  html:
    theme:
      light: flatly
      dark: darkly

Any simple index.qmd file can be paired with this project definition.

Expected behavior

The toggle button remains on the right of the screen.

Actual behavior

The toggle button moves left, adjacent to the title.

Your environment

No response

Quarto check output

Quarto 1.4.551
[✓] Checking versions of quarto binary dependencies...
      Pandoc version 3.1.11: OK
      Dart Sass version 1.69.5: OK
      Deno version 1.37.2: OK
[✓] Checking versions of quarto dependencies......OK
[✓] Checking Quarto installation......OK
      Version: 1.4.551
      Path: /Users/aron/quarto/quarto-1.4.551-macos/bin

[✓] Checking tools....................OK
      TinyTeX: (not installed)
      Chromium: (not installed)

[✓] Checking LaTeX....................OK
      Using: Installation From Path
      Path: /Library/TeX/texbin
      Version: 2024

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

[✓] Checking Python 3 installation....OK
      Version: 3.12.2
      Path: /opt/homebrew/opt/python@3.12/bin/python3.12
      Jupyter: (None)

      Jupyter is not available in this Python installation.
      Install with python3 -m pip install jupyter

[✓] Checking R installation...........OK
      Version: 4.3.3
      Path: /Library/Frameworks/R.framework/Resources
      LibPaths:
        - /Library/Frameworks/R.framework/Versions/4.3-arm64/Resources/library
      knitr: 1.45
      rmarkdown: 2.27

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

Start by rendering the minimal website configuration from the issue at a small viewport and inspect the generated navbar and its responsive styles. Done means the dark mode toggle remains aligned on the right side of the screen while the title and navigation still render correctly.