use-theme

Global theme state hook with localStorage persistence for brand, surface and color mode

Installation

$npx litefy@latest add use-theme
$pnpm dlx litefy@latest add use-theme
$yarn dlx litefy@latest add use-theme
$bun --bun litefy@latest add use-theme

A module-level store shared across components via useSyncExternalStore. Reads brand / surface / theme from localStorage on load, applies them to document.documentElement (data-brand, data-surface, .dark, color-scheme) and follows the system color scheme when theme is "system".

Current theme: light

Surface (neutral)

Brand (primary)

"use client";

/* design-detect-disable-file hardcoded-color
   use-theme 演示需要直接书写各主题的 oklch 色值 */

import { Button, useTheme } from "@/ui";

const SURFACES = [
  { value: "", color: "oklch(55.6% 0 none)" },
  { value: "olive", color: "oklch(58% 0.031 107.3)" },
  { value: "mist", color: "oklch(56% 0.021 213.5)" },
  { value: "mauve", color: "oklch(54.2% 0.034 322.5)" },
  { value: "taupe", color: "oklch(54.7% 0.021 43.1)" },
  { value: "stone", color: "oklch(55.3% 0.013 58.071)" },
  { value: "zinc", color: "oklch(55.2% 0.016 285.938)" },
  { value: "slate", color: "oklch(55.4% 0.046 257.417)" },
  { value: "gray", color: "oklch(55.1% 0.027 264.364)" },
];

const BRANDS = [
  { value: "", color: "oklch(55.6% 0 none)" },
  { value: "cyan", color: "oklch(70.6% 0.137 204)" },
  { value: "violet", color: "oklch(60.6% 0.25 292.717)" },
  { value: "teal", color: "oklch(70.4% 0.14 182.503)" },
  { value: "sky", color: "oklch(68.5% 0.135 217)" },
  { value: "rose", color: "oklch(64.5% 0.246 16.439)" },
  { value: "purple", color: "oklch(62.7% 0.265 303.9)" },
  { value: "pink", color: "oklch(65.6% 0.241 354.308)" },
  { value: "orange", color: "oklch(70.5% 0.213 47.604)" },
  { value: "lime", color: "oklch(76.8% 0.233 130.85)" },
  { value: "indigo", color: "oklch(58.5% 0.233 277.117)" },
  { value: "fuchsia", color: "oklch(66.7% 0.295 322.15)" },
  { value: "emerald", color: "oklch(69.6% 0.17 162.48)" },
  { value: "amber", color: "oklch(76.9% 0.188 70.08)" },
];

export default function UseThemeBasicDemo() {
  const theme = useTheme();

  return (
    <div className="flex flex-col items-center gap-4 py-4">
      <p className="text-sm text-muted-foreground">
        Current theme: <span className="font-medium text-foreground">{theme.theme}</span>
      </p>
      <div className="flex gap-2">
        {(["light", "dark", "system"] as const).map((mode) => (
          <Button
            key={mode}
            variant={theme.theme === mode ? "primary" : "outline"}
            onClick={() => theme.setTheme(mode)}
            className="capitalize"
          >
            {mode}
          </Button>
        ))}
      </div>
      <div className="flex flex-col items-center gap-2">
        <span className="text-xs text-muted-foreground">Surface (neutral)</span>
        <ul className="flex max-w-full flex-wrap justify-center gap-2">
          {SURFACES.map((surface) => (
            <li key={surface.value}>
              <button
                type="button"
                aria-label={surface.value || "default"}
                title={surface.value || "default"}
                onClick={() => theme.setSurface(surface.value)}
                className={
                  "size-6 cursor-pointer rounded-full transition-transform hover:scale-110" +
                  (theme.surface === surface.value
                    ? " ring-2 ring-ring ring-offset-2 ring-offset-background"
                    : "")
                }
                style={{ backgroundColor: surface.color }}
              />
            </li>
          ))}
        </ul>
      </div>
      <div className="flex flex-col items-center gap-2">
        <span className="text-xs text-muted-foreground">Brand (primary)</span>
        <ul className="flex max-w-full flex-wrap justify-center gap-2">
          {BRANDS.map((brand) => (
            <li key={brand.value}>
              <button
                type="button"
                aria-label={brand.value || "default"}
                title={brand.value || "default"}
                onClick={() => theme.setBrand(brand.value)}
                className={
                  "size-6 cursor-pointer rounded-full transition-transform hover:scale-110" +
                  (theme.brand === brand.value
                    ? " ring-2 ring-ring ring-offset-2 ring-offset-background"
                    : "")
                }
                style={{ backgroundColor: brand.color }}
              />
            </li>
          ))}
        </ul>
      </div>
    </div>
  );
}

Theming tokens

surface and brand switch the CSS variable sets defined in app/ui/styles/*-surface.css and app/ui/styles/*-brand.css. The preview above lets you switch them live. To install a preset palette statically, see Styles.

Surface

The surface palette is a neutral color system for containers:

Token	Purpose
`--background` / `--foreground`	Containers that carry content, e.g. popover, sidebar, card, paper
`--muted`	Areas that should not draw attention, e.g. the app-level background; content containers are painted with the more prominent `--background`, so users focus on them against the muted backdrop
`--muted-foreground`	Description text, one step weaker than body text
`--accent`	Hover states and skeleton backgrounds

Brand

The brand palette is the theme color system. Except for the default black-and-white theme, brands are colorful:

Token	Purpose
`--primary`	The main brand color, used for emphasized actions and states
`--accent`	The reinforced primary color, used for hover scenarios
`--ring`	Borders and focus outlines, also part of the brand color family

API Reference

useTheme

function useTheme(): ThemeState

Returns a ThemeState:

Property	Type	Description
`brand`	`string`	Current brand token, mapped to `data-brand` on the root element
`surface`	`string`	Current surface token, mapped to `data-surface` on the root element
`theme`	`'light' \| 'dark' \| 'system'`	Current color mode
`setBrand`	`(brand: string) => void`	Set the brand token, persists and applies it
`setSurface`	`(surface: string) => void`	Set the surface token, persists and applies it
`setTheme`	`(mode: ThemeMode) => void`	Set the color mode, persists and applies it
`toggleTheme`	`() => void`	Switch between light and dark (resolves system first)

Notes:

All state lives outside React; multiple components calling useTheme share one store and re-render together.
Persisted under the theme-storage localStorage key.
When theme is "system", the stored value is kept and the applied mode follows prefers-color-scheme changes live.