Use bootstrap() to compile Bootstrap Sass into CSS and return it, along with other HTML dependencies, as a list of htmltools::htmlDependency()s (if you just want the CSS as a string, and a bs_theme_new() has been set, you can call sass::sass() on the return value of bs_theme_get()). Use bootstrap_sass() if you can assume Bootstrap already exists on the page, but you want to leverage Bootstrap utilities (e.g., variables, functions, or mixins) to generate additional CSS rules (as a string that can be included as a <style> tag via tags$style(css)).

  theme = bs_theme_get(),
  jquery = jquerylib::jquery_core(3),
  options = sass::sass_options(),
  minified = TRUE,

bootstrap_sass(rules = list(), theme = bs_theme_get(), ...)



one of the following:

  1. The result of bs_theme_get() (i.e., the current global theme).

  2. NULL, which means use the latest version of Bootstrap with no custom theming.

  3. A string containing a bootswatch theme and/or a Bootstrap major version. To specify both, use the syntax "theme@version", (e.g., "cosmo@4" for Bootstrap 4 cosmo theme with BS3 compatibility). If no version is specified, the latest available version is used (for more info, see version in bs_theme_new()). Note: this approach ignores global themes (i.e., bs_theme_new())

  4. A sass::sass_layer() which contains a bootstraplib theme. Useful for adding custom layers to the current theme without affecting the global state (e.g., sass::sass_layer_merge(bs_theme_get(), my_layer())).


See jquerylib::jquery_core().


Compiler options for Sass. Please specify options using sass_options.


whether the resulting HTML dependency should minify the JS/CSS files.


arguments passed along to sass::sass()


Sass styling rules that may reference theme defaults and declarations.

See also


# Function to preview the styling a (primary) Bootstrap button library(htmltools) button <- tags$a(class = "btn btn-primary", href = "#", role = "button", "Hello") preview_button <- function(x) { browsable(tags$body(x, button)) } # Latest bootstrap preview_button(bootstrap()) # Bootstrap 3 preview_button(bootstrap("3")) # Bootswatch minty theme preview_button(bootstrap("minty")) # Bootswatch sketchy theme preview_button(bootstrap("sketchy")) # Bootswatch solar theme with BS3 compatibility preview_button(bootstrap("solar@4+3"))