Implement different custom CSS (font color) for kable headers in continuous tables

Question

I want a blue title and then a red title. Icat two HTML sections, first blue and second red, according to this answer, But I get red on both.

How to get blue title and red title?

---
output: html_document
---
```{r setup, include=FALSE}
knitr::opts_chunk$set(echo=FALSE)
```

```{r results="asis"}

cat("
<style>
caption {
      color: blue;
    }
</style>
")

knitr::kable(head(iris),
             format="html",
             digits=4,
             row.names=FALSE,
             caption='Caption blue',
             escape=TRUE)|>
  kableExtra::kable_styling(font_size=14) |>
  kableExtra::kable_paper(c('hover', 'condensed', 'responsive'), full_width=T) |>
  kableExtra::scroll_box(width="100%", height="200px")
```


```{r results="asis"}

cat("
<style>
caption {
      color: red;
    }
</style>
")


knitr::kable(head(iris),
             format="html",
             digits=4,
             row.names=FALSE,
             caption='Caption red',
             escape=TRUE) |>
  kableExtra::kable_styling(font_size=14) |>
  kableExtra::kable_paper(c('hover', 'condensed', 'responsive'), full_width=T) |>
  kableExtra::scroll_box(width="100%", height="200px")
```

Answer 1

You can also provide a special HTML class for each table and collect all styles in a css block instead of specifying CSS in each block:

---
output: html_document
---

```{r setup, include=FALSE}
knitr::opts_chunk$set(echo=FALSE)
```

```{css}
.mytable1 > caption {
    color: blue;
}
.mytable2 > caption {
    color: red;
}
```

```{r results="asis"}
knitr::kable(head(iris), 
             format="html",
             digits=4,
             row.names=FALSE,
             caption='Caption blue',
             escape=TRUE)|>
  kableExtra::kable_styling(font_size=14, htmltable_class = "mytable1") |>
  kableExtra::kable_paper(c('hover', 'condensed', 'responsive'), full_width=T) |>
  kableExtra::scroll_box(width="100%", height="200px") 
```


```{r results="asis"}
knitr::kable(head(iris), 
             format="html",
             digits=4,
             row.names=FALSE,
             caption='Caption red',
             escape=TRUE) |>
  kableExtra::kable_styling(font_size=14, htmltable_class = "mytable2") |>
  kableExtra::kable_paper(c('hover', 'condensed', 'responsive'), full_width=T) |>
  kableExtra::scroll_box(width="100%", height="200px")
```

Alternatively, we can insert inline CSS outside the block.

<style>
.mytable1 > caption {
  color: blue;
}
.mytable2 > caption {
  color: red;
}
</style>

Answer 2

Because the second CSS overwrites the first CSS.

Better to do this:

cat("
<style>
.blue-caption {
      color: blue;
    }

.red-caption {
      color: red;
    }
</style>
")

Then use like this:

caption='<span class=\"blue-caption\">Caption blue</span>',
caption='<span class=\"red-caption\">Caption red</span>',

Is it valid?

greeting, Noel