6.1 KiB
| title | path |
|---|---|
| Theming | getting-started/theming |
Primer CSS offers multiple color themes for components and utilities. The colors change based on the active theme and color mode.
Currently there are 3 themes (light, dark, dark_dimmed) to choose from. When nothing is specified, Primer CSS uses the light theme.
Set a theme
Configure Primer CSS to use a certain theme by adding the following attributes:
data-color-modewith a value of eitherlightordark- either
data-light-themeordata-dark-themewith a value of eitherlight,dark,dark_dimmed
The attributes can be added to any element, but ideally it should be added to the document root (<html>). Below an example to use the dark_dimmed theme:
<html data-color-mode="dark" data-dark-theme="dark_dimmed">
More examples:
<div data-color-mode="light" data-light-theme="light" class="p-3">
<h4>Light</h4>
<code class="d-block mt-1 mb-3 color-text-secondary">
data-color-mode="light" data-light-theme="light"
</code>
<button class="btn">Button</button>
<span class="Label ml-2">Label</span>
<span class="Counter ml-2">123</span>
</div>
<div data-color-mode="dark" data-dark-theme="dark" class="p-3">
<h4>Dark</h4>
<code class="d-block mt-1 mb-3 color-text-secondary">
data-color-mode="dark" data-dark-theme="dark"
</code>
<button class="btn">Button</button>
<span class="Label ml-2">Label</span>
<span class="Counter ml-2">123</span>
</div>
<div data-color-mode="dark" data-dark-theme="dark_dimmed" class="p-3">
<h4>Dark Dimmed</h4>
<code class="d-block mt-1 mb-3 color-text-secondary">
data-color-mode="dark" data-dark-theme="dark_dimmed"
</code>
<button class="btn">Button</button>
<span class="Label ml-2">Label</span>
<span class="Counter ml-2">123</span>
</div>
Sync to the system
If the theme should be synced to the OS's color mode, use data-color-mode="auto" and set a data-light-theme as well as a data-dark-theme.
<div data-color-mode="auto" data-light-theme="light" data-dark-theme="dark_dimmed" class="p-3">
<h4>Synced to system</h4>
<code class="d-block mt-1 mb-3 color-text-secondary">
data-color-mode="auto" data-light-theme="light" data-dark-theme="dark_dimmed"
</code>
<button class="btn">Button</button>
<span class="Label ml-2">Label</span>
<span class="Counter ml-2">123</span>
</div>
Change the color mode of your OS to see the switch between the data-light-theme="light" and data-dark-theme="dark_dimmed".
Custom color variables
It's recommended to use the functional variables as much as possible. It will guarantee that the variables will work as expected with any new theme that might get added in the future. Somtimes you might still need a custom variable that changes based on the color mode. You can create a custom variable with the color-variables mixin.
@include color-variables(
("custom-css-variable-1": (
light: var(--color-scale-gray-3),
dark: var(--color-scale-gray-5)
),
"custom-css-variable-2": (
light: var(--color-scale-gray-2),
dark: var(--color-scale-gray-6)
),
"custom-css-variable-3": (
light: var(--color-scale-gray-2),
dark: var(--color-scale-gray-6)
)
));
The custom variables will be prefixed with --color- and can be used in the same way as other functional variables.
.my-class {
color: var(--color-custom-css-variable-1);
background-color: var(--color-custom-css-variable-2);
border-color: var(--color-custom-css-variable-2);
}
Auto variables
If you tried using the scale color variables you might have noticed that they are not that useful with multiple color modes. That's because they stay light or dark in any color mode. As seen above, you could create custom variables that invert the scale like so:
@include color-variables(
("custom-css-variable": (
light: var(--color-scale-gray-7),
dark: var(--color-scale-gray-2)
)
));
.my-class {
color: var(--color-custom-css-variable);
}
In this case, the auto variables might come in handy.
.my-class {
color: var(--color-auto-gray-7);
}
The benefit of auto over the scale variables is that auto variables automatically get inverted in dark mode.
<div data-color-mode="light" data-light-theme="light" class="p-3">
<code style="color: var(--color-auto-gray-7)">--color-auto-gray-7</code>
<code style="color: var(--color-scale-gray-7)">--color-scale-gray-7</code><br>
<code style="color: var(--color-auto-blue-7)">--color-auto-blue-7</code>
<code style="color: var(--color-scale-blue-7)">--color-scale-blue-7</code><br>
<code style="color: var(--color-auto-green-7)">--color-auto-green-7</code>
<code style="color: var(--color-scale-green-7)">--color-scale-green-7</code>
</div>
<div data-color-mode="dark" data-dark-theme="dark" class="p-3">
<code style="color: var(--color-auto-gray-7)">--color-auto-gray-7</code>
<code style="color: var(--color-scale-gray-7)">--color-scale-gray-7</code><br>
<code style="color: var(--color-auto-blue-7)">--color-auto-blue-7</code>
<code style="color: var(--color-scale-blue-7)">--color-scale-blue-7</code><br>
<code style="color: var(--color-auto-green-7)">--color-auto-green-7</code>
<code style="color: var(--color-scale-green-7)">--color-scale-green-7</code>
</div>
<div data-color-mode="dark" data-dark-theme="dark_dimmed" class="p-3">
<code style="color: var(--color-auto-gray-7)">--color-auto-gray-7</code>
<code style="color: var(--color-scale-gray-7)">--color-scale-gray-7</code><br>
<code style="color: var(--color-auto-blue-7)">--color-auto-blue-7</code>
<code style="color: var(--color-scale-blue-7)">--color-scale-blue-7</code><br>
<code style="color: var(--color-auto-green-7)">--color-auto-green-7</code>
<code style="color: var(--color-scale-green-7)">--color-scale-green-7</code>
</div>
<style>code { margin-right: 16px; }</style>
In general, use auto variables if the results give enough constrast or create custom variables for further fine tuning.