Make lightbox work with absolute positioning

I have:

• searched the issue tracker for similar issues
• installed the latest version of Quarto CLI
• formatted my issue following the Bug Reports guide

Bug description

The combination of Lightbox and absolute positioning results in the image being hidden.

Use case: Display a small image in the top-right corner, use Lightbox during presentation to show the image full size.

Steps to reproduce

The following document demonstrates the issue. A screenshot of the rendered version is included below.

![][logo]{.lightbox}
![][logo]{.absolute top=20 right=20}
![][logo]{.absolute bottom=50 right=20 .lightbox}

```{=html}
<div style="border: 2px dashed #000; border-radius: 10px; padding: 45px 170px; position: absolute; bottom: 50px; right: 5px;"></div>
```

[logo]: https://quarto.org/quarto.png

The rendered version was produced as follows:

$ podman run --rm -v .:/workspace -w /workspace ghcr.io/quarto-dev/quarto:1.9.2 quarto render mwe.md --to revealjs

Actual behavior

The first two images are visible while the third one is hidden. The <div> indicates the position of the missing image in the rendered document as shown below.

Expected behavior

Third image is shown and Lightbox works.

Your environment

No response

Quarto check output

Quarto 1.9.2                                                                                                                                                                                                         
[✓] Checking environment information...                                                                                                                                                                              
      Quarto cache location: /root/.cache/quarto                                                                                                                                                                     
[✓] Checking versions of quarto binary dependencies...                                                                                                                                                               
      Pandoc version 3.6.3: OK                                                                                                                                                                                       
      Dart Sass version 1.87.0: OK                                                                                                                                                                                   
      NOTE: Deno version 2.4.5 does not strictly match 2.3.1 and strict checking is enabled. Please use 2.3.1.                                                                                                       
      Typst version 0.13.0: OK                                                                                                                                                                                       
[✓] Checking versions of quarto dependencies......OK                                                                                                                                                                 
[✓] Checking Quarto installation......OK                                                                                                                                                                             
      Version: 1.9.2                                                                                                                                                                                                 
      Path: /opt/quarto/bin

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

[✓] Checking LaTeX....................OK
      Tex:  (not detected)

[✓] Checking Chrome Headless....................OK
      Chrome:  (not detected)
Quarto 1.9.2                                                                                                                                                                                                         
[✓] Checking environment information...                                                                                                                                                                              
      Quarto cache location: /root/.cache/quarto                                                                                                                                                                     
[✓] Checking versions of quarto binary dependencies...                                                                                                                                                               
      Pandoc version 3.6.3: OK                                                                                                                                                                                       
      Dart Sass version 1.87.0: OK                                                                                                                                                                                   
      NOTE: Deno version 2.4.5 does not strictly match 2.3.1 and strict checking is enabled. Please use 2.3.1.                                                                                                       
      Typst version 0.13.0: OK                                                                                                                                                                                       
[✓] Checking versions of quarto dependencies......OK                                                                                                                                                                 
[✓] Checking Quarto installation......OK                                                                                                                                                                             
      Version: 1.9.2                                                                                                                                                                                                 
      Path: /opt/quarto/bin

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

[✓] Checking LaTeX....................OK
      Tex:  (not detected)

[✓] Checking Chrome Headless....................OK
      Chrome:  (not detected)

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

[✓] Checking Python 3 installation....(None)

      Unable to locate an installed version of Python 3.
      Install Python 3 from https://www.python.org/downloads/

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/
[✓] Checking basic markdown render....OK

[✓] Checking Python 3 installation....(None)

      Unable to locate an installed version of Python 3.
      Install Python 3 from https://www.python.org/downloads/

[✓] Checking R installation...........(None)

      Unable to locate an installed version of R.
      Install R from https://cloud.r-project.org/