Mode Watcher

Simple utilities to manage light & dark mode in your SvelteKit app.

Installation

npm install mode-watcher

Usage

Add the ModeWatcher component to your root +layout.svelte file.

<script lang="ts">
	import { ModeWatcher } from 'mode-watcher';
</script>

<ModeWatcher />
<slot />

The ModeWatcher component will automatically detect the user's preferences and apply/remove the "dark" class, along with the corresponding color-scheme style attribute to the html element.

ModeWatcher will automatically track operating system preferences and apply these if no user preference is set. If you wish to disable this behavior, set the track prop to false:

<ModeWatcher track={false} />

ModeWatcher can also be configured with a default mode instead of automatically detecting the user's preference.

To set a default mode, use the defaultMode prop:

<ModeWatcher defaultMode={"dark"}>

ModeWatcher can manage the theme-color meta tag for you.

To enable this, set the themeColors prop to your preferred colors:

<ModeWatcher themeColors={{ dark: "black", light: "white" }}>

API

toggleMode

A function that toggles the current mode.

<script lang="ts">
	import { toggleMode } from 'mode-watcher';
</script>

<button on:click={toggleMode}>Toggle Mode</button>

setMode

A function that sets the current mode. It accepts a string with the value "light", "dark" or "system".

<script lang="ts">
	import { setMode } from 'mode-watcher';
</script>

<button on:click={() => setMode('light')}>Set Light Mode</button>
<button on:click={() => setMode('dark')}>Set Dark Mode</button>

resetMode

A function that resets the mode to system preferences.

<script lang="ts">
	import { resetMode } from 'mode-watcher';
</script>

<button on:click={() => resetMode()}>System</button>

mode

A readable store that contains the current mode. It can be "light" or "dark" or undefined if evaluated on the server.

<script lang="ts">
	import { setMode, mode } from 'mode-watcher';

	function handleModeChange() {
		if ($mode === 'light') {
			setMode('dark');
		} else {
			setMode('light');
		}
	}
</script>

<button on:click={handleModeChange}>{$mode}</button>

userPrefersMode

A writeable store that represents the user's mode preference. It can be "light", "dark" or "system".

systemPrefersMode

A readable store that represents the operating system's mode preference. It can be "light", "dark" or undefined if evaluated on the server. Will automatically track changes to the operating system's mode preference unless this is disabled with the tracking() method which takes a boolean. Normally this is disabled by setting the track prop to false in the <ModeWatcher> component.

Demo / Reproduction Template