Creates a Bootstrap theme object which can be:

These functions (i.e., bs_theme() or bs_theme_update()) allow you to do the following common Bootstrap customization(s):

  • Choose a (major) Bootstrap version.

  • Choose a Bootswatch theme (optional).

  • Customize main colors and fonts via explicitly named arguments (e.g., bg, fg, primary, etc).

  • Customize other, lower-level, Bootstrap Sass variable defaults via ...

For less common theming customization(s), you can modify theme objects to:

These lower-level theming tools build on the concept of a sass::sass_layer(). To learn more, see here.

bs_theme(
  version = version_default(),
  bootswatch = NULL,
  ...,
  bg = NULL,
  fg = NULL,
  primary = NULL,
  secondary = NULL,
  success = NULL,
  info = NULL,
  warning = NULL,
  danger = NULL,
  base_font = NULL,
  code_font = NULL,
  heading_font = NULL
)

bs_theme_update(
  theme,
  ...,
  bootswatch = NULL,
  bg = NULL,
  fg = NULL,
  primary = NULL,
  secondary = NULL,
  success = NULL,
  info = NULL,
  warning = NULL,
  danger = NULL,
  base_font = NULL,
  code_font = NULL,
  heading_font = NULL
)

is_bs_theme(x)

Arguments

version

The major version of Bootstrap to use (see versions() for possible values).

bootswatch

The name of a bootswatch theme (see bootswatch_themes() for possible values). When provided to bs_theme_update(), any previous Bootswatch theme is first removed before the new one is applied (use bootswatch = "default" to effectively remove the Bootswatch theme).

...

arguments passed along to bs_add_variables().

bg

A color string for the background.

fg

A color string for the foreground.

primary

A color to be used for hyperlinks, to indicate primary/default actions, and to show active selection state in some Bootstrap components. Generally a bold, saturated color that contrasts with the theme's base colors.

secondary

A color for components and messages that don't need to stand out. (Not supported in Bootstrap 3.)

success

A color for messages that indicate an operation has succeeded. Typically green.

info

A color for messages that are informative but not critical. Typically a shade of blue-green.

warning

A color for warning messages. Typically yellow.

danger

A color for errors. Typically red.

base_font

The default typeface.

code_font

The typeface to be used for code. Be sure this is monospace!

heading_font

The typeface to be used for heading elements.

theme

a bs_theme() object.

x

an object.

Value

a sass::sass_bundle() (list-like) object.

Colors

Colors may be provided in any format that htmltools::parseCssColors() can understand. To control the vast majority of the ('grayscale') color defaults, specify both the fg (foreground) and bg (background) colors. The primary and secondary theme colors are also useful for accenting the main grayscale colors in things like hyperlinks, tabset panels, and buttons.

Fonts

Use base_font, code_font, and heading_font to control the main typefaces. These arguments set new defaults for the relevant font-family CSS properties, but don't necessarily import the relevant font files. To both set CSS properties and import font files, consider using the various font_face() helpers.

Each *_font argument may be collection of character vectors, font_google()s, font_link()s and/or font_face()s. Note that a character vector can have:

Since font_google(..., local = TRUE) guarantees that the client has access to the font family, meaning it's relatively safe to specify just one font family, for instance:

bs_theme(base_font = font_google("Pacifico", local = TRUE))

However, specifying multiple "fallback" font families is recommended, especially when relying on remote and/or system fonts being available, for instance. Fallback fonts are useful not only for handling missing fonts, but also for handling a Flash of Invisible Text (FOIT) which can be quite noticeable with remote web fonts on a slow internet connection.

bs_theme(base_font = list(font_google("Pacifico", local = FALSE), "Roboto", "sans-serif")

References

https://getbootstrap.com/docs/4.4/getting-started/theming/

https://rstudio.github.io/sass/

See also

Examples

theme <- bs_theme( # Controls the default grayscale palette bg = "#202123", fg = "#B8BCC2", # Controls the accent (e.g., hyperlink, button, etc) colors primary = "#EA80FC", secondary = "#48DAC6", base_font = c("Grandstander", "sans-serif"), code_font = c("Courier", "monospace"), heading_font = "'Helvetica Neue', Helvetica, sans-serif", # Can also add lower-level customization "input-border-color" = "#EA80FC" ) if (interactive()) { bs_theme_preview(theme) } # Lower-level bs_add_*() functions allow you to work more # directly with the underlying Sass code theme <- theme %>% bs_add_variables("my-class-color" = "red") %>% bs_add_rules(".my-class { color: $my-class-color }")