ioslides_presentation: External CSS Sheet with Runtime: Shiny

[danam322]

Hi,

I'm trying to include an external css sheet including, in particular, an image for the title slide background for an ioslides presentation using some shiny features on some slides, but it seems like no css is being implemented. When I remove runtime: shiny, the css is then implemented into the presentation.

I've seen this issue raised in other places, but most of the time it was said to have been resolved with a package update. Ex: this StackOverflow question. In that particular question, I tried the two solutions offered by the other answerer as well, with no luck.

Code is below. Apologies if this has been resolved already...

Thank you!

Rmarkdown file (no css styling)

---
title: "Untitled"
author: ""
date: "`r Sys.Date()`"
runtime: shiny
output: 
  ioslides_presentation:
    widescreen: true
    self_contained: false
    css: styles.css
---

## R Markdown 
test text

## Slide with Bullets

- Bullet 1
- Bullet 2
- Bullet 3

CSS Sheet

slides > slide.title-slide {
  background-image: url("background.jpg");
  background-size: 100% 100%;
  text-align: center;
  
}

h1, h2, h3 {
  text-align: center;
}

RMarkdown File (with css styling, no runtime: shiny)

---
title: "Untitled"
author: ""
date: "`r Sys.Date()`"
output: 
  ioslides_presentation:
    widescreen: true
    self_contained: false
    css: styles.css
---

## R Markdown 
test text

## Slide with Bullets

- Bullet 1
- Bullet 2
- Bullet 3

R Session Info

R version 4.2.2 (2022-10-31 ucrt)
Platform: x86_64-w64-mingw32/x64 (64-bit)
Running under: Windows 10 x64 (build 19044), RStudio 2023.3.1.446

Locale:
  LC_COLLATE=English_United States.utf8  LC_CTYPE=English_United States.utf8   
  LC_MONETARY=English_United States.utf8 LC_NUMERIC=C                          
  LC_TIME=English_United States.utf8    

Package version:
  askpass_1.1       base64enc_0.1.3   bslib_0.4.2       cachem_1.0.8      cli_3.6.1        
  compiler_4.2.2    curl_5.0.0        digest_0.6.31     ellipsis_0.3.2    evaluate_0.21    
  fastmap_1.1.1     fontawesome_0.5.1 fs_1.6.2          glue_1.6.2        graphics_4.2.2   
  grDevices_4.2.2   highr_0.10        htmltools_0.5.5   jquerylib_0.1.4   jsonlite_1.8.5   
  knitr_1.43        lifecycle_1.0.3   magrittr_2.0.3    memoise_2.0.1     methods_4.2.2    
  mime_0.12         openssl_2.0.6     packrat_0.9.1     R6_2.5.1          rappdirs_0.3.3   
  rlang_1.1.1       rmarkdown_2.22    rsconnect_0.8.29  rstudioapi_0.14   sass_0.4.6       
  stats_4.2.2       stringi_1.7.12    stringr_1.5.0     sys_3.4.2         tinytex_0.45     
  tools_4.2.2       utils_4.2.2       vctrs_0.6.2       xfun_0.39         yaml_2.3.7