In bookdown how can I set the default color on code output

I would like to have the text output from my bookdown book appear in a white box with a black boarder. The R Markdown Cookbook shows how to set the style for a specific block but I don't see how to set the default. If anybody knows how can you please respond on stack overflow: https://stackoverflow.com/questions/65495605/in-r-bookdown-how-do-i-set-the-default-code-output-background-color (or here).

I answered there too

The previous answer is correct for the CSS rule but the selector must be more specific for a gitbook() format. This a matter of CSS specificity.

Using a browser inspector, you can get a sense of the selector you need to use to override default CSS style set by gitbook.

This simple css will replace background and add a border

.book .book-body .page-wrapper .page-inner section.normal pre {
    background: #fff;
    border: 1px solid #ddd;
    border-color: #000;
}

You put in as you do in style.css and use the css argument of bookdown::gitbook in index.Rmd or in _output.ymldepending of which you are using.

This will pick up the CSS.

I think you could also use !important to have the most specify on pre with

pre {
    background: #fff !important;
    border: 1px solid #ddd !important;
    border-color: #000 !important;
}

I sincerely appreciate the help! I posted a follow-up question on SO...

Your code styles both the code and output the same. Is there a way to limit it to only applying this to the output? I inspected the html and the code is tagged with and the output is tagged with

. Is there a way to NOT apply your change to the "sourceCode r" chunks? In other words, I want to keep the default style for the code and use your code for only the output.

For reference this topic has been answered on Stackoverflow.