[ @sdxc/u/color ]

color

Applies color (foreground text color).

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import { fg } from "@sdxc/u/color";

Quick reference

Every documented call, beside the CSS it emits.

Call	CSS
`u.fg()`	`css({ color: "var(--ui-fg, CanvasText)" })`
`u.fg("brand.muted")`	`css({ color: "var(--ui-brand-fg-muted)" })`
`u.fg("brand")`	`css({ color: "var(--ui-brand-fg)" })`

Examples

Basic example

Use fg to set the text color of an element, from the page's default fg() to a tone and weight like neutral.muted:

fg() reads the page's own text color.

fg("neutral.muted") is for secondary copy.

fg("brand") draws the eye to a link or an accent.

<div mix={[...]}>
	<p mix={[fg(), ...]}>fg() reads the page's own text color.</p>
	<p mix={[fg("neutral.muted"), ...]}>fg("neutral.muted") is for secondary copy.</p>
	<p mix={[fg("brand"), ...]}>fg("brand") draws the eye to a link or an accent.</p>
</div>

Text weights

A bare tone resolves its plain fg weight; add muted or emphasis for a softer or a stronger one:

fg("danger.muted")

fg("danger")

fg("danger.emphasis")

<div mix={[...]}>
	<p mix={[fg("danger.muted"), ...]}>fg("danger.muted")</p>
	<p mix={[fg("danger"), ...]}>fg("danger")</p>
	<p mix={[fg("danger.emphasis"), ...]}>fg("danger.emphasis")</p>
</div>

Text on solid backgrounds

Pair a solid background with the same tone's onSolid text weight, like brand.onSolid, so the text keeps its contrast:

fg("brand.onSolid")

fg("neutral.onSolid")

fg("success.onSolid")

<div mix={[...]}>
	<div mix={[bg("brand.solid"), fg("brand.onSolid"), ...]}>fg("brand.onSolid")</div>
	<div mix={[bg("neutral.solid"), fg("neutral.onSolid"), ...]}>
		fg("neutral.onSolid")
	</div>
	<div mix={[bg("success.solid"), fg("success.onSolid"), ...]}>
		fg("success.onSolid")
	</div>
</div>

Palette shades and arbitrary colors

Use a palette shade like color.brand.400, or any CSS color function, when no tone names the color:

fg("color.brand.400")

fg("color.success.600")

fg("oklch(0.65 0.2 30)")

<div mix={[...]}>
	<p mix={[fg("color.brand.400"), ...]}>fg("color.brand.400")</p>
	<p mix={[fg("color.success.600"), ...]}>fg("color.success.600")</p>
	<p mix={[fg("oklch(0.65 0.2 30)"), ...]}>fg("oklch(0.65 0.2 30)")</p>
</div>

Applying on a state

Wrap the call in a state utility to scope it to one selector.

u.hover(u.fg())

Responsive design

Wrap the call in a container query to scope it to one width.

u.at("md", u.fg())

Customizing your theme

Customizing colors

Define a palette as --ui-color-{name}-{50..950} and map a tone onto it with the --ui-{tone}-* variables, the way theme.css maps the built-in ones:

:root {
	--ui-color-info-50: oklch(0.97 0.02 230);
	--ui-color-info-200: oklch(0.88 0.06 230);
	--ui-color-info-500: oklch(0.62 0.16 230);
	--ui-color-info-600: oklch(0.52 0.18 230);
	--ui-color-info-900: oklch(0.3 0.1 230);

	--ui-info-bg-tint: var(--ui-color-info-50);
	--ui-info-bg-solid: var(--ui-color-info-600);
	--ui-info-fg: var(--ui-color-info-600);
	--ui-info-fg-muted: var(--ui-color-info-500);
	--ui-info-fg-emphasis: var(--ui-color-info-900);
	--ui-info-fg-on-solid: white;
	--ui-info-border: var(--ui-color-info-200);
	--ui-info-border-strong: var(--ui-color-info-600);
	--ui-info-ring: var(--ui-color-info-500);
}

declare module "@sdxc/u" {
	interface ColorPalettes {
		info: true;
	}
	interface SemanticTones {
		info: true;
	}
}

The new name is then accepted wherever the scale is:

fg("info")

Signature

u.fg(value?: ColorValue | (string & {}))