--- layout: docs title: Customization options description: Customize Bootstrap 4 with our new built-in Sass variables for global style preferences for easy theming and component changes. group: getting-started toc: true --- ## Customizing variables Every Sass variable in Bootstrap 4 includes the `!default` flag, meaning you can override that default value in your own Sass. Copy and paste variables as needed, modify the values and remove the !default flag. If a variable has already been assigned, then it won't be re-assigned by the default values in Bootstrap. This means that your modified Sass variables should be called before you import Bootstrap Sass files. For example, to change out the `background-color` and `color` for the ``, you'd do the following:: {% highlight scss %} // Your variable overwrite first or a Sass file containing the modifications $body-bg: #000; $body-color: #111; // Then import Bootstrap @import "node_modules/bootstrap/scss/bootstrap"; {% endhighlight %} Do the same for any variable you need to override, including the global options listed below. ## Global options Customize Bootstrap 4 with our built-in custom variables file and easily toggle global CSS preferences with new `$enable-*` Sass variables. Override a variable's value and recompile with `npm run test` as needed. You can find and customize these variables for key global options in our `_variables.scss` file. | Variable | Values | Description | | --------------------------- | ---------------------------------- | -------------------------------------------------------------------------------------- | | `$spacer` | `1rem` (default), or any value > 0 | Specifies the default spacer value to programmatically generate our [spacer utilities]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/spacing/). | | `$enable-rounded` | `true` (default) or `false` | Enables predefined `border-radius` styles on various components. | | `$enable-shadows` | `true` or `false` (default) | Enables predefined `box-shadow` styles on various components. | | `$enable-gradients` | `true` or `false` (default) | Enables predefined gradients via `background-image` styles on various components. | | `$enable-transitions` | `true` (default) or `false` | Enables predefined `transition`s on various components. | | `$enable-hover-media-query` | `true` or `false` (default) | ... | | `$enable-grid-classes` | `true` (default) or `false` | Enables the generation of CSS classes for the grid system (e.g., `.container`, `.row`, `.col-md-1`, etc.). | | `$enable-print-styles` | `true` (default) or `false` | Enables styles for optimizing printing. | ## Color Many of Bootstrap's various components and utilities are built through a series of colors defined in a Sass map. This map can be looped over in Sass to quickly generate a series of rulesets. ### All colors All colors available in Bootstrap 4, available as Sass variables and a Sass map in our `scss/_variables.scss` file. This will be expanded upon in subsequent minor releases to add additional shades, much like the [grayscale palette](#grays) we already include.

{% for color in site.data.colors %} {% unless color.name == "white" or color.name == "gray" or color.name == "gray-dark" %}

{% endunless %} {% endfor %}

Here's how you can use these in your Sass: {% highlight scss %} // With variable .alpha { color: $purple; } // From the Sass map with our `color()` function .beta { color: color("purple"); } {% endhighlight %} [Color utility classes]({{ site.baseurl }}/docs/{{ site.docs_version }}/utilities/colors/) are also available for setting `color` and `background-color`. {% callout info %} In the future, we'll aim to provide Sass maps and variables for shades of each color as we've done with the grayscale colors below. {% endcallout %} ### Theme colors We use a subset of all colors to create a smaller color palette for generating color schemes, also available as Sass variables and a Sass map in our `scss/_variables.scss` file.

{% for color in site.data.theme-colors %}

{% endfor %}

### Grays An expansive set of gray variables and a Sass map in `scss/_variables.scss` for consistent shades of gray across your project.

{% for color in site.data.grays %}

{% endfor %}

Within `_variables.scss`, you'll find our color variables and Sass map. Here's an example of the `$colors` Sass map: {% highlight scss %} $colors: ( red: $red, orange: $orange, yellow: $yellow, green: $green, teal: $teal, blue: $blue, pink: $pink, purple: $purple, white: $white, gray: $gray-600, gray-dark: $gray-900 ) !default; {% endhighlight %} Add, remove, or modify values within the map to update how they're used in many other components. Unfortunately at this time, not _every_ component utilizes this Sass map. Future updates will strive to improve upon this. Until then, plan on making use of the `${color}` variables and this Sass map.