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@alec.brunelle/darkmode-js v1.5.0

🌓 Add darkmode / nightmode to your website in a few seconds

Darkmode.js GitHub

🌓 Add a Dark Mode / Night Mode to your website in a few seconds

This library uses the css mix-blend-mode in order to bring Dark Mode to any of your websites. Just copy paste the snippet and you will get a widget to turn on and off the Dark Mode. You can also use it without the widget programmatically. The plugin is lightweight, built in Vanilla. It also uses localstorage by default, so your last setting will be remembered!

I have been inspired by this article:


  • Widget appears automatically
  • Saving users choice
  • Automatically shows Darkmode if the OS prefered theme is dark (if the browsers supports prefers-color-scheme)
  • Can be used programmatically without widget

✨ Demo

Check out the demo in these websites:

  • (with custom label)
  • (with custom label)
  • (without the widget, once logged in)
  • (with custom label)

Wordpress plugins

If you are using Wordpress you may want have a look to these plugins based on Darkmode.js:


📖 How to use

Darkmode.js is very easy to use, just copy paste the following code or use the npm package.

🚀 Easy way (using the JSDelivr CDN)

Just add this code to your HTML page:

<script src=""></script>
  new Darkmode().showWidget();

📦 Using NPM

npm install darkmode-js

Then add the following JavaScript code:

import Darkmode from 'darkmode-js';

new Darkmode().showWidget();

⚙️ Options

Here are the option availables:

var options = {
  bottom: '64px', // default: '32px'
  right: 'unset', // default: '32px'
  left: '32px', // default: 'unset'
  time: '0.5s', // default: '0.3s'
  mixColor: '#fff', // default: '#fff'
  backgroundColor: '#fff',  // default: '#fff'
  buttonColorDark: '#100f2c',  // default: '#100f2c'
  buttonColorLight: '#fff', // default: '#fff'
  saveInCookies: false, // default: true,
  label: '🌓', // default: ''
  autoMatchOsTheme: true // default: true

const darkmode = new Darkmode(options);

▶️ Methods

If you don't want to show the widget and enable/disable Darkmode programatically you can use the method toggle(). You can also check if the Dark Mode is activated with the method isActivated(). See them in action in the following example:

const darkmode =  new Darkmode();
console.log(darkmode.isActivated()) // will return true

Override style

  • A CSS class darkmode--activated is added to the body tag when the darkmode is activated. You can take advantage of it to override the style and have a custom style
  • Use the class darkmode-ignore where you don't want to apply darkmode
  • You can also add this style: isolation: isolate; in your CSS, this will also ignore the darkmode.
  • It is also possible to revert the Dark Mode with this style mix-blend-mode: difference;


.darkmode--activated p, .darkmode--activated li {
  color: #000;

.button {
  isolation: isolate;

.darkmode--activated .logo {
  mix-blend-mode: difference;
<span class="darkmode-ignore">😬<span>


If it does not work you may have to add the following code, but this will invalidate the classes to override.

.darkmode-layer, .darkmode-toggle {
  z-index: 500;

Browser compatibility

This library uses the CSS mix-blend-mode: difference; in order to provide the Dark Mode. It may not be compatible with all the browsers. Therefore the widget has been hidden in Internet Explorer and Edge. This library also uses prefers-color-scheme: dark to automatically enable the Dark Mode if the OS prefered theme is dark.

Check the compatibility here:

  • (to activate Dark Mode automatically)


  • yarn build or npm run build - produces production version of your library under the lib folder
  • yarn dev or npm run dev - produces development version of your library and runs a watcher
  • yarn test or npm run test - it runs the tests :)
  • yarn test:watch or npm run test:watch - same as above but in a watch mode

⭐️ Show your support

Please ⭐️ this repository if this project helped you!


🍺 Buy me a beer

If you like this project, feel free to donate:

  • PayPal:
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  • Motive: MOTIV-25T5-SD65-V7LJ-BBWRD (Get Motive Now:
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