Themes – Carbon Design System

Themes are used to customize component styles to fit the specific aesthetic of a brand or product.

Theming basics
Customizing a theme
Tokens
Theming applied
Resources

Theming basics

Themes are used to modify existing components to fit a specific visual style. By using Carbon’s tokens, developers can easily customize all of their components by changing a set of universal variables, eliminating the need to modify individual components.

Theme terms

Term	Definition
Theme	A collection of visual attributes assigned to the tokens in order to create a specific aesthetic
Token	A role-based identifier that assigns a value to a theme. Tokens are universal and never change across themes
Role	The systematic usage(s) of a token. Roles cannot be changed between themes
Value	The actual style (such as a hex code) assigned to a token

Default theme

Carbon provides four themes as shown in the color usage page. When carbon-components is downloaded and installed, the components are preset to use the default (White) theme.

To use the Gray 10, Gray 90, or Gray 100 theme as your default instead of White, set the $carbon--theme variable to one of the available theme maps ($carbon--theme--g10, $carbon--theme--g90, $carbon--theme--g100) and then include your normal components in your Sass build. These need to be imported before the main Carbon styles.

@import '@carbon/themes/scss/themes';

// Use the gray 10 theme
$carbon--theme: $carbon--theme--g10;
@include carbon--theme();

// Use the gray 90 theme
$carbon--theme: $carbon--theme--g90;
@include carbon--theme();

Customizing a theme

The default theme acts as a starting point; from there designers and developers can define how their own components and styles deviate from the default. Altering one, some, or all of the default token values will result in a new theme. The developer then packages those new values into a new theme SCSS stylesheet which will replace the values of the default theme.

1. Create a theme mixin that effectively mimics this structure, but changes up values as needed:

$carbon--theme--white: (
  // Background
  background: #ffffff,
  background-active: #c6c6c6,
  background-hover: #e5e5e5,
  background-selected: #e0e0e0,
  background-selected-hover: #cacaca,
  background-inverse: #393939,
  background-inverse-hover: #4c4c4c,

2. Name the mixin:

i.e., $my-theme

3. Include this in your SCSS, before importing components, etc.:

@include my-theme();

Alternatively, for relatively minor changes to an existing theme, a developer can make changes on a per-token basis. For example, after importing an existing Carbon theme, she could just set something like $interactive: hotpink;.

Tokens

With tokens, the code only needs to be changed in one place to see the effect system-wide. Tokens are used across all components and help keep global patterns and styles consistent.

All tokens come pre-baked into the Carbon component source code. Tokens are denoted by the prefix $ (e.g. $layer-01). Tokens can also be nested within other tokens. For example, $interactive calls the IBM Design Language color palette token $blue-60 for its value in the default theme.

There are several token categories:

Color
Spacing
Typography
Global

Color

Each theme is assigned universal color variables, which are determined by common roles and usage. This allows for uniform color application across themes while maintaining full styling flexibility. For more information, see the color page.

$carbon--theme--white: (
  // Background
  background: #ffffff,
  background-active: #c6c6c6,
  background-hover: #e5e5e5,
  background-selected: #e0e0e0,
  background-selected-hover: #cacaca,
  background-inverse: #393939,
  background-inverse-hover: #4c4c4c,

Spacing

Use the spacing scale when building individual components. It includes small increments needed to create appropriate spatial relationships for detail-level designs. For more information, see the spacing page.

  $spacing-01: 0.125rem,
  $spacing-02: 0.25rem,
  $spacing-03: 0.5rem,
  $spacing-04: 0.75rem,
  $spacing-05: 1rem,
  $spacing-06: 1.5rem,
  $spacing-07: 2rem,
  $spacing-08: 2.5rem,
  $spacing-09: 3rem,

Typography

Typography has four categories of type styles (universal, productive, editorial, and additional) that can be customized through tokens. These tokens are used both within components and across layouts. Type tokens are determined by their role across the system. For more information, see the typography page.

// Universal
$caption-01: (
  font-family: carbon--font-family('sans'),
  font-size: carbon--type-scale(1),
  font-weight: carbon--font-weight('regular'),
  line-height: carbon--rem(16px),
  letter-spacing: 0.32px,
) !default;

// Productive
$productive-heading-03: (
  font-family: carbon--font-family('sans'),
  font-size: carbon--type-scale(5),
  font-weight: carbon--font-weight('regular'),
  line-height: carbon--rem(26px),
  letter-spacing: 0,
) !default;

// Expressive
$expressive-heading-03: (
  font-family: carbon--font-family('sans'),
  font-size: carbon--type-scale(5),
  font-weight: carbon--font-weight('regular'),
  line-height: 130%,
  letter-spacing: 0,
  breakpoints: (
    xlg: (

// Additional styles
$quotation-01: (
  font-family: carbon--font-family('serif'),
  font-size: carbon--type-scale(5),
  font-weight: carbon--font-weight('regular'),
  line-height: 130%,
  letter-spacing: 0,
  breakpoints: (
    md: (

Global

The other categories are global and component-specific variables. These control more general styling of components, such as layer usage or border width.

// Global
$input-border: 1px solid transparent !default !global;
$input-label-weight: 400 !default !global;
$disabled: $disabled-02 !default !global;
$disabled-background-color: $disabled-01 !default !global;
$focus: $ibm-color__blue-60 !default !global;

// Link
$link-visited: $ibm-color__purple-60 !default !global;

Theming applied

The following example demonstrates the relationship between the different themes. Each theme shares the same variables and roles, with only the value changing for each individual theme.

Key	Token	Role	White theme value	Gray 100 theme value
1	`$text-secondary`	Label color	Gray 70	Gray 30
2	`$text-primary`	Primary text color	Gray 100	Gray 10
3	`$border-strong`	Border bottom color	Gray 50	Gray 60
4	`$icon-primary`	Primary icon color	Gray 100	Gray 10
5	`$field-01`	Field color	Gray 10	Gray 90
6	`$background`	Page background	White	Gray 100

Resources

Carbon themes package

Edit this page on GitHub

Guidelines: Spacing

Themes: Code