A Simple CSS Trick for Dark Mode on Your Website

The Night Mode Awaits!

by Jun 17, 2024Development


Picture this: It’s late at night, the moon is high, and you’re comfortably browsing your favorite site when—BAM!—the bright white background hits you like a spotlight. Not ideal, right?

Developers often turn this simple problem into a tech labyrinth, adding tons of classes, styles, and JavaScript files. But, dear reader, there’s a far easier way to achieve dark mode with less than 20 lines of CSS magic. Yes, you heard that right—20 lines!

Simplifying Dark Mode

By leveraging CSS, you can allow your website to seamlessly adapt to your users’ preferred theme. How? By tweaking --body-bg and --body-color CSS variables using media queries. In light mode, we’ll set the background to white and in dark mode, black. Here’s how:

@media (prefers-color-scheme: dark) {
  :root {
    --body-bg: black;
    --body-color: white;

@media (prefers-color-scheme: light) {
  :root {
    --body-bg: white;
    --body-color: black;

Voilà! Now your site can transition from day to night as smoothly as a jazz musician switching keys.

How It Works

The key to this magic is the prefers-color-scheme media query. This media query checks the user’s system preference and applies the corresponding styles. When the user prefers a dark theme, the CSS variables --body-bg and --body-color are set to black and white, respectively. Conversely, if the user prefers a light theme, these variables are set to white and black.

Why Dark Mode?

But why even bother with dark mode? Here are a few reasons:

  1. Reduces Eye Strain: Especially in low-light environments, dark mode can be easier on the eyes.
  2. Saves Battery Life: On OLED screens, dark mode can save battery life because black pixels consume less power.
  3. Looks Cool: Let’s be honest, dark mode just looks sleek and modern.

Implementing Dark Mode in Your Project

To integrate this CSS trick into your project, follow these steps:

  1. Define the Variables: Set up your CSS variables at the root level, so they can be accessed throughout your stylesheet.
  2. Apply the Media Queries: Use the prefers-color-scheme media query to adjust these variables based on the user’s preference.
  3. Style Your Elements: Use these variables in your CSS to ensure that your entire site respects the dark mode settings.


body {
  background-color: var(--body-bg);
  color: var(--body-color);

Conclusion: The Night Mode Awaits!

And there you have it! A quick and fun guide to making your web development life a bit easier. If only everything in tech could be this simple, right? Now go forth and code without fear of blinding your users or getting tangled in arrays! Whether you’re a night owl coding in the wee hours or just someone who loves a sleek, modern look, this simple CSS trick has got you covered.

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