Skip to content
GitLab
Switch branch/tag
Find file Normal viewHistoryPermalink
theming.md 18.6 KB
Newer Older
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
1
2
3
4
5
6
7
8
9
10
11
12 
---
layout: docs
title: Theming Bootstrap
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
---

## Introduction

In Bootstrap 3, theming was largely driven by variable overrides in LESS, custom CSS, and a separate theme stylesheet that we included in our `dist` files. With some effort, one could completely redesign the look of Bootstrap 3 without touching the core files. Bootstrap 4 provides a familiar, but slightly different approach.
Gijs Boddeus's avatar
spelling changes to theming.md (#24444)    
Gijs Boddeus committed
13 
Now, theming is accomplished by Sass variables, Sass maps, and custom CSS. There's no more dedicated theme stylesheet; instead, you can enable the built-in theme to add gradients, shadows, and more.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
14
15
16 

## Sass
Martijn Cuppens's avatar
Sass precision documentation (#27705)    
Martijn Cuppens committed
17 
Utilize our source Sass files to take advantage of variables, maps, mixins, and more. In our build we've increased the Sass rounding precision to 6 (by default it's 5) to prevent issues with browser rounding.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
18
19
20 

### File structure
Mark Otto's avatar
fixes #24728    
Mark Otto committed
21 
Whenever possible, avoid modifying Bootstrap's core files. For Sass, that means creating your own stylesheet that imports Bootstrap so you can modify and extend it. Assuming you're using a package manager like npm, you'll have a file structure that looks like this:
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
22
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
23 
{{< highlight text >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
24
25
26
27
28
29
30 
your-project/
├── scss
│   └── custom.scss
└── node_modules/
    └── bootstrap
        ├── js
        └── scss
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
31 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
32
Mark Otto's avatar
fixes #24728    
Mark Otto committed
33
34 
If you've downloaded our source files and aren't using a package manager, you'll want to manually setup something similar to that structure, keeping Bootstrap's source files separate from your own.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
35 
{{< highlight text >}}
Mark Otto's avatar
fixes #24728    
Mark Otto committed
36
37
38
39
40
41 
your-project/
├── scss
│   └── custom.scss
└── bootstrap/
    ├── js
    └── scss
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
42 
{{< /highlight >}}
Mark Otto's avatar
fixes #24728    
Mark Otto committed
43
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
44
45 
### Importing
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
46
47 
In your `custom.scss`, you'll import Bootstrap's source Sass files. You have two options: include all of Bootstrap, or pick the parts you need. We encourage the latter, though be aware there are some requirements and dependencies across our components. You also will need to include some JavaScript for our plugins.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
48 
{{< highlight scss >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
49
50
51 
// Custom.scss
// Option A: Include all of Bootstrap
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
52 
@import "../node_modules/bootstrap/scss/bootstrap";
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
53 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
54
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
55 
{{< highlight scss >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
56
57
58
59 
// Custom.scss
// Option B: Include parts of Bootstrap

// Required
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
60
61
62 
@import "../node_modules/bootstrap/scss/functions";
@import "../node_modules/bootstrap/scss/variables";
@import "../node_modules/bootstrap/scss/mixins";
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
63
64 

// Optional
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
65
66
67
68
69 
@import "../node_modules/bootstrap/scss/reboot";
@import "../node_modules/bootstrap/scss/type";
@import "../node_modules/bootstrap/scss/images";
@import "../node_modules/bootstrap/scss/code";
@import "../node_modules/bootstrap/scss/grid";
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
70 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
71
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
72 
With that setup in place, you can begin to modify any of the Sass variables and maps in your `custom.scss`. You can also start to add parts of Bootstrap under the `// Optional` section as needed. We suggest using the full import stack from our `bootstrap.scss` file as your starting point.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
73
74
75 

### Variable defaults
Mark Otto's avatar
port latest from options for default vars    
Mark Otto committed
76 
Every Sass variable in Bootstrap 4 includes the `!default` flag allowing you to override the variable's default value in your own Sass without modifying Bootstrap's source code. Copy and paste variables as needed, modify their 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.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
77
Martijn Cuppens's avatar
Make component colors configurable (#28035)    
Martijn Cuppens committed
78 
You will find the complete list of Bootstrap's variables in `scss/_variables.scss`. Some variables are set to `null`, these variables don't output the property unless they are overridden in your configuration.
Pierre GIRAUD's avatar
Be more explicit where to find variables (#25624)    
Pierre GIRAUD committed
79
Mark Otto's avatar
port latest from options for default vars    
Mark Otto committed
80
81
82 
Variable overrides within the same Sass file can come before or after the default variables. However, when overriding across Sass files, your overrides must come before you import Bootstrap's Sass files.

Here's an example that changes the `background-color` and `color` for the `<body>` when importing and compiling Bootstrap via npm:
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
83
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
84 
{{< highlight scss >}}
Mark Otto's avatar
port latest from options for default vars    
Mark Otto committed
85
86
87
88
89 
// Your variable overrides
$body-bg: #000;
$body-color: #111;

// Bootstrap and its default variables
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
90 
@import "../node_modules/bootstrap/scss/bootstrap";
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
91 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
92
Mark Otto's avatar
port latest from options for default vars    
Mark Otto committed
93 
Repeat as necessary for any variable in Bootstrap, including the global options below.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
94
95
96
97
98 

### Maps and loops

Bootstrap 4 includes a handful of Sass maps, key value pairs that make it easier to generate families of related CSS. We use Sass maps for our colors, grid breakpoints, and more. Just like Sass variables, all Sass maps include the `!default` flag and can be overridden and extended.
Mark Otto's avatar
Update Theming docs for removing map items (#25108)    
Mark Otto committed
99
100 
Some of our Sass maps are merged into empty ones by default. This is done to allow easy expansion of a given Sass map, but comes at the cost of making _removing_ items from a map slightly more difficult.
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
101
102 
#### Modify map
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
103
104
105
106
107
108
109
110 
All variables in the `$theme-colors` map are defined as standalone variables. To modify an existing color in our `$theme-colors` map, add the following to your custom Sass file:

{{< highlight scss >}}
$primary: #0074d9;
$danger: #ff4136;
{{< /highlight >}}

Later on, theses variables are set in Bootstrap's `$theme-colors` map:
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
111
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
112 
{{< highlight scss >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
113 
$theme-colors: (
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
114
115 
  "primary": $primary,
  "danger": $danger
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
116 
);
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
117 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
118
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
119
120 
#### Add to map
Mark Otto's avatar
add new thing to a map    
Mark Otto committed
121
122 
To add a new color to `$theme-colors`, add the new key and value:
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
123 
{{< highlight scss >}}
Mark Otto's avatar
add new thing to a map    
Mark Otto committed
124
125
126 
$theme-colors: (
  "custom-color": #900
);
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
127 
{{< /highlight >}}
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
128
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
129
130 
#### Remove from map
ysds's avatar
Update themeing docs for more clearly how to remove from map (#25589)    
ysds committed
131 
To remove colors from `$theme-colors`, or any other map, use `map-remove`. Be aware you must insert it between our requirements and options:
Mark Otto's avatar
Update Theming docs for removing map items (#25108)    
Mark Otto committed
132
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
133 
{{< highlight scss >}}
ysds's avatar
Update themeing docs for more clearly how to remove from map (#25589)    
ysds committed
134 
// Required
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
135
136
137 
@import "../node_modules/bootstrap/scss/functions";
@import "../node_modules/bootstrap/scss/variables";
@import "../node_modules/bootstrap/scss/mixins";
ysds's avatar
Update themeing docs for more clearly how to remove from map (#25589)    
ysds committed
138
139
140
141 

$theme-colors: map-remove($theme-colors, "info", "light", "dark");

// Optional
Martijn Cuppens's avatar
Fix node_modules path (#26653)    
Martijn Cuppens committed
142
143
144 
@import "../node_modules/bootstrap/scss/root";
@import "../node_modules/bootstrap/scss/reboot";
@import "../node_modules/bootstrap/scss/type";
ysds's avatar
Update themeing docs for more clearly how to remove from map (#25589)    
ysds committed
145 
...
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
146 
{{< /highlight >}}
Mark Otto's avatar
Update Theming docs for removing map items (#25108)    
Mark Otto committed
147
Mark Otto's avatar
Theming docs update (#25300)    
Mark Otto committed
148
149
150
151
152
153 
#### Required keys

Bootstrap assumes the presence of some specific keys within Sass maps as we used and extend these ourselves. As you customize the included maps, you may encounter errors where a specific Sass map's key is being used.

For example, we use the `primary`, `success`, and `danger` keys from `$theme-colors` for links, buttons, and form states. Replacing the values of these keys should present no issues, but removing them may cause Sass compilation issues. In these instances, you'll need to modify the Sass code that makes use of those values.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
154
155 
### Functions
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
156 
In Bootstrap 5, we've dropped the `color()`, `theme-color()` and `gray()` functions because the values are also available as standalone variables. So instead of using `theme-color("primary")`, you can now just use the `$primary` variable.
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
157
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
158 
{{< highlight scss >}}
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
159 
.custom-element {
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
160
161 
  color: $gray-100;
  background-color: $dark;
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
162 
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
163 
{{< /highlight >}}
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
164
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
165 
We also have a function for getting a particular _level_ of color. Negative level values will lighten the color, while higher levels will darken.
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
166
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
167 
{{< highlight scss >}}
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
168 
@function color-level($color: $primary, $level: 0) {
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
169
170
171
172
173 
  $color-base: if($level > 0, #000, #fff);
  $level: abs($level);

  @return mix($color-base, $color, $level * $theme-color-interval);
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
174 
{{< /highlight >}}
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
175
176
177 

In practice, you'd call the function and pass in two parameters: the name of the color from `$theme-colors` (e.g., primary or danger) and a numeric level.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
178 
{{< highlight scss >}}
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
179 
.custom-element {
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
180 
  color: color-level($primary, -10);
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
181 
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
182 
{{< /highlight >}}
Mark Otto's avatar
functions aww yeah    
Mark Otto committed
183
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
184
185 
### Color contrast
Martijn Cuppens's avatar
Use escape-svg() function (#29077)    
Martijn Cuppens committed
186 
An additional function we include in Bootstrap is the color contrast function, `color-yiq`. It utilizes the [YIQ color space](https://en.wikipedia.org/wiki/YIQ) to automatically return a light (`#fff`) or dark (`#111`) contrast color based on the specified base color. This function is especially useful for mixins or loops where you're generating multiple classes.
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
187
188
189 

For example, to generate color swatches from our `$theme-colors` map:
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
190 
{{< highlight scss >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
191
192
193
194
195 
@each $color, $value in $theme-colors {
  .swatch-#{$color} {
    color: color-yiq($value);
  }
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
196 
{{< /highlight >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
197
198
199 

It can also be used for one-off contrast needs:
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
200 
{{< highlight scss >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
201
202
203 
.custom-element {
  color: color-yiq(#000); // returns `color: #fff`
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
204 
{{< /highlight >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
205
206
207 

You can also specify a base color with our color map functions:
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
208 
{{< highlight scss >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
209 
.custom-element {
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
210 
  color: color-yiq($dark); // returns `color: #fff`
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
211 
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
212 
{{< /highlight >}}
Mark Otto's avatar
document color-yiq function    
Mark Otto committed
213
Martijn Cuppens's avatar
Use escape-svg() function (#29077)    
Martijn Cuppens committed
214
215
216
217 
## Escape SVG

We use the `escape-svg` function to escape the `<`, `>` and `#` characters for SVG background images. These characters need to be escaped to properly render the background images in IE.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
218
219 
## Sass options
Mark Otto's avatar
port over variable options list    
Mark Otto committed
220
221 
Customize Bootstrap 4 with our built-in custom variables file and easily toggle global CSS preferences with new `$enable-*` Sass variables. Override a variable's value and recompile with `npm run test` as needed.
Pierre GIRAUD's avatar
Be more explicit where to find variables (#25624)    
Pierre GIRAUD committed
222 
You can find and customize these variables for key global options in Bootstrap's `scss/_variables.scss` file.
Mark Otto's avatar
port over variable options list    
Mark Otto committed
223
Martijn Cuppens's avatar
Move hand cursor for buttons to reboot    
Martijn Cuppens committed
224
225 
| Variable                                     | Values                             | Description                                                                            |
| -------------------------------------------- | ---------------------------------- | -------------------------------------------------------------------------------------- |
XhmikosR's avatar
Add a docsref shortcode.    
XhmikosR committed
226 
| `$spacer`                                    | `1rem` (default), or any value > 0 | Specifies the default spacer value to programmatically generate our [spacer utilities]({{< docsref "/utilities/spacing" >}}). |
Martijn Cuppens's avatar
Move hand cursor for buttons to reboot    
Martijn Cuppens committed
227
228
229
230 
| `$enable-rounded`                            | `true` (default) or `false`        | Enables predefined `border-radius` styles on various components. |
| `$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. |
XhmikosR's avatar
Add a docsref shortcode.    
XhmikosR committed
231 
| `$enable-prefers-reduced-motion-media-query` | `true` (default) or `false`        | Enables the [`prefers-reduced-motion` media query]({{< docsref "/getting-started/accessibility#reduced-motion" >}}), which suppresses certain animations/transitions based on the users' browser/operating system preferences. |
Martijn Cuppens's avatar
Move hand cursor for buttons to reboot    
Martijn Cuppens committed
232
233
234 
| `$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.). |
| `$enable-caret`                              | `true` (default) or `false`        | Enables pseudo element caret on `.dropdown-toggle`. |
| `$enable-pointer-cursor-for-buttons`         | `true` (default) or `false`        | Add "hand" cursor to non-disabled button elements. |
XhmikosR's avatar
Add a docsref shortcode.    
XhmikosR committed
235 
| `$enable-responsive-font-sizes`              | `true` or `false` (default)        | Enables [responsive font sizes]({{< docsref "/content/typography#responsive-font-sizes" >}}). |
Martijn Cuppens's avatar
Move hand cursor for buttons to reboot    
Martijn Cuppens committed
236 
| `$enable-validation-icons`                   | `true` (default) or `false`        | Enables `background-image` icons within textual inputs and some custom forms for validation states. |
Martijn Cuppens's avatar
Add `deprecate()` mixin (#28092)    
Martijn Cuppens committed
237 
| `$enable-deprecation-messages`               | `true` or `false` (default)        | Set to `true` to show warnings when using any of the deprecated mixins and functions that are planned to be removed in `v5`. |
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
238
Mark Otto's avatar
bring over colors section    
Mark Otto committed
239 
## Color
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
240
Mark Otto's avatar
bring over colors section    
Mark Otto committed
241
242
243
244 
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
Mark Otto's avatar
v5: Update colors to add shades and tints (#29348)    
Mark Otto committed
245
246
247
248
249 
All colors available in Bootstrap 5, are available as Sass variables and a Sass map in `scss/_variables.scss` file. To avoid increased file sizes, we do not create classes for each of these variables.

Sass cannot programmatically generate variables, so we must manually create them ourselves. We specify the midpoint value (`500`) and use custom color functions to tint (lighten) or shade (darken) our colors via Sass's `mix()` color function. Using `mix()` is not the same as `lighten()` and `darken()`—the former blends the specified color with white or black, while the latter only adjusts the lightness value of each color. The result is a much more complete suite of colors, as [shown in this CodePen demo](https://codepen.io/emdeoh/pen/zYOQOPB).

Our `tint-color()` and `shade-color()` functions use `mix()` alongside our `$theme-color-interval` variable, which specifies a stepped percentage value for each mixed color we need. See the `scss/_functions.scss` and `scss/_variables.scss` files for the full source code.
Mark Otto's avatar
bring over colors section    
Mark Otto committed
250
251 

<div class="row">
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
252 
  {{< theme-colors.inline >}}
Mark Otto's avatar
v5: Update colors to add shades and tints (#29348)    
Mark Otto committed
253
254
255
256
257
258
259
260
261
262 
  {{- range $color := $.Site.Data.colors }}
    {{- if (and (not (eq $color.name "white")) (not (eq $color.name "gray")) (not (eq $color.name "gray-dark"))) }}
    <div class="col-md-4 mb-3 font-monospace">
      <div class="p-3 mb-2 swatch-{{ $color.name }}">
        <strong class="d-block">${{ $color.name }}</strong>
        {{ $color.hex }}
      </div>
      {{ range (seq 100 100 900) }}
      <div class="p-3 bd-{{ $color.name }}-{{ . }}">${{ $color.name }}-{{ . }}</div>
      {{ end }}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
263 
    </div>
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
264
265
266 
    {{ end -}}
  {{ end -}}
  {{< /theme-colors.inline >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
267
268
269
270 
</div>

Here's how you can use these in your Sass:
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
271 
{{< highlight scss >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
272 
.alpha { color: $purple; }
Mark Otto's avatar
v5: Update colors to add shades and tints (#29348)    
Mark Otto committed
273
274
275
276 
.beta {
  color: $yellow-300;
  background-color: $indigo-900;
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
277 
{{< /highlight >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
278
XhmikosR's avatar
Add a docsref shortcode.    
XhmikosR committed
279 
[Color utility classes]({{< docsref "/utilities/colors" >}}) are also available for setting `color` and `background-color`.
Mark Otto's avatar
bring over colors section    
Mark Otto committed
280
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
281 
{{< callout info >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
282 
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.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
283 
{{< /callout >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
284
285
286 

### Theme colors
Martijn Cuppens's avatar
Typo fix (#28920)    
Martijn Cuppens committed
287 
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 Bootstrap's `scss/_variables.scss` file.
Mark Otto's avatar
bring over colors section    
Mark Otto committed
288
289 

<div class="row">
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
290
291 
  {{< theme-colors.inline >}}
  {{- range (index $.Site.Data "theme-colors") }}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
292 
    <div class="col-md-4">
XhmikosR's avatar
docs: remove swatches for theme colors. (#29327)    
XhmikosR committed
293 
      <div class="p-3 mb-3 bg-{{ .name }} {{ if or (eq .name "light") (eq .name "warning") }}text-dark{{ else }}text-white{{ end }}">{{ .name | title }}</div>
Mark Otto's avatar
bring over colors section    
Mark Otto committed
294 
    </div>
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
295
296 
  {{ end -}}
  {{< /theme-colors.inline >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
297
298
299
300 
</div>

### Grays
Patrick H. Lauke's avatar
Docs: add note about the grays being "cool" (#27824)    
Patrick H. Lauke committed
301 
An expansive set of gray variables and a Sass map in `scss/_variables.scss` for consistent shades of gray across your project. Note that these are "cool grays", which tend towards a subtle blue tone, rather than neutral grays.
Mark Otto's avatar
bring over colors section    
Mark Otto committed
302
303
304 

<div class="row mb-3">
  <div class="col-md-4">
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
305
306
307
308
309 
    {{< theme-colors.inline >}}
    {{- range $.Site.Data.grays }}
      <div class="p-3 swatch-{{ .name }}">{{ .name }}</div>
    {{ end -}}
  {{< /theme-colors.inline >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
310
311
312 
  </div>
</div>
Pierre GIRAUD's avatar
Be more explicit where to find variables (#25624)    
Pierre GIRAUD committed
313 
Within `scss/_variables.scss`, you'll find Bootstrap's color variables and Sass map. Here's an example of the `$colors` Sass map:
Mark Otto's avatar
bring over colors section    
Mark Otto committed
314
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
315 
{{< highlight scss >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
316 
$colors: (
Jesse Mandel's avatar
Update colors in _data and theming.md to match _variables.scss (#24355)    
Jesse Mandel committed
317
318
319
320 
  "blue": $blue,
  "indigo": $indigo,
  "purple": $purple,
  "pink": $pink,
Mark Otto's avatar
quote those to match source code    
Mark Otto committed
321
322
323
324
325 
  "red": $red,
  "orange": $orange,
  "yellow": $yellow,
  "green": $green,
  "teal": $teal,
Jesse Mandel's avatar
Update colors in _data and theming.md to match _variables.scss (#24355)    
Jesse Mandel committed
326 
  "cyan": $cyan,
Mark Otto's avatar
quote those to match source code    
Mark Otto committed
327
328 
  "white": $white,
  "gray": $gray-600,
Jesse Mandel's avatar
Update colors in _data and theming.md to match _variables.scss (#24355)    
Jesse Mandel committed
329 
  "gray-dark": $gray-800
Mark Otto's avatar
bring over colors section    
Mark Otto committed
330 
) !default;
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
331 
{{< /highlight >}}
Mark Otto's avatar
bring over colors section    
Mark Otto committed
332
333
334 

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 `${color}` variables and this Sass map.
Mark Otto's avatar
Stub out new Theming page  
Mark Otto committed
335
336 
## Components
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
337
338
339
340
341
342
343
344 
Many of Bootstrap's components and utilities are built with `@each` loops that iterate over a Sass map. This is especially helpful for generating variants of a component by our `$theme-colors` and creating responsive variants for each breakpoint. As you customize these Sass maps and recompile, you'll automatically see your changes reflected in these loops.

### Modifiers

Many of Bootstrap's components are built with a base-modifier class approach. This means the bulk of the styling is contained to a base class (e.g., `.btn`) while style variations are confined to modifier classes (e.g., `.btn-danger`). These modifier classes are built from the `$theme-colors` map to make customizing the number and name of our modifier classes.

Here are two examples of how we loop over the `$theme-colors` map to generate modifiers to the `.alert` component and all our `.bg-*` background utilities.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
345 
{{< highlight scss >}}
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
346
347
348 
// Generate alert modifier classes
@each $color, $value in $theme-colors {
  .alert-#{$color} {
Martijn Cuppens's avatar
Drop `color()`, `theme-color()` & `gray()` functions (#29083)    
Martijn Cuppens committed
349 
    @include alert-variant(color-level($color, -10), color-level($color, -9), color-level($color, 6));
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
350
351
352
353
354
355
356 
  }
}

// Generate `.bg-*` color utilities
@each $color, $value in $theme-colors {
  @include bg-variant('.bg-#{$color}', $value);
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
357 
{{< /highlight >}}
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
358
359
360
361
362 

### Responsive

These Sass loops aren't limited to color maps, either. You can also generate responsive variations of your components or utilities. Take for example our responsive text alignment utilities where we mix an `@each` loop for the `$grid-breakpoints` Sass map with a media query include.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
363 
{{< highlight scss >}}
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
364
365
366
367
368
369
370
371
372 
@each $breakpoint in map-keys($grid-breakpoints) {
  @include media-breakpoint-up($breakpoint) {
    $infix: breakpoint-infix($breakpoint, $grid-breakpoints);

    .text#{$infix}-left   { text-align: left !important; }
    .text#{$infix}-right  { text-align: right !important; }
    .text#{$infix}-center { text-align: center !important; }
  }
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
373 
{{< /highlight >}}
Mark Otto's avatar
add components section, remove todos    
Mark Otto committed
374
375 

Should you need to modify your `$grid-breakpoints`, your changes will apply to all the loops iterating over that map.
Mark Otto's avatar
Add some documentation on using CSS vars (#25176)    
Mark Otto committed
376
377
378 

## CSS variables
XhmikosR's avatar
Fix redirects. (#29254)    
XhmikosR committed
379 
Bootstrap 4 includes around two dozen [CSS custom properties (variables)](https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_custom_properties) in its compiled CSS. These provide easy access to commonly used values like our theme colors, breakpoints, and primary font stacks when working in your browser's Inspector, a code sandbox, or general prototyping.
Mark Otto's avatar
Add some documentation on using CSS vars (#25176)    
Mark Otto committed
380
381
382
383
384 

### Available variables

Here are the variables we include (note that the `:root` is required). They're located in our `_root.scss` file.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
385 
{{< highlight css >}}
XhmikosR's avatar
theming.md: automate _root.scss. (#29326)    
XhmikosR committed
386
387
388
389 
{{< root.inline >}}
{{- $css := readFile "dist/css/bootstrap.css" -}}
{{- $match := findRE ":root {([^}]*)}" $css 1 -}}
XhmikosR's avatar
getting-started/theming.md: throw an error if the regex doesn't succeed.    
XhmikosR committed
390
391
392
393 
{{- if (eq (len $match) 0) -}}
{{- errorf "Got no matches for :root in %q!" $.Page.Path -}}
{{- end -}}
XhmikosR's avatar
theming.md: automate _root.scss. (#29326)    
XhmikosR committed
394
395
396 
{{- index $match 0 -}}

{{< /root.inline >}}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
397 
{{< /highlight >}}
Mark Otto's avatar
Add some documentation on using CSS vars (#25176)    
Mark Otto committed
398
399
400
401
402 

### Examples

CSS variables offer similar flexibility to Sass's variables, but without the need for compilation before being served to the browser. For example, here we're resetting our page's font and link styles with CSS variables.
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
403 
{{< highlight css >}}
Mark Otto's avatar
Add some documentation on using CSS vars (#25176)    
Mark Otto committed
404
405
406
407
408
409 
body {
  font: 1rem/1.5 var(--font-family-sans-serif);
}
a {
  color: var(--blue);
}
XhmikosR's avatar
Switch to Hugo.    
XhmikosR committed
410 
{{< /highlight >}}