CSS

Updating CSS Variables with Javascript

If you are building an application or SaaS platform, or in fact any website, it can be useful to store all your colours as CSS variables, and then update these once to change the theme of the app.

Fortunately this is relatively straightforward to accomplish. Imagine you have your CSS variables set up like this:

    :root {
        --main-background: blue;
        --main-sidebar: red;
        /* Yes these colors do not match */
    }

:root CSS styles are stored on document.documentElement. So we can access all of its styles via that. So in JS, all we need to do is this:

    document.documentElement.style.setProperty("--main-background", "yellow");

More Tips and Tricks for CSS

• CSS Fonts
• CSS Pixel Art Generator
• CSS Transformations
• How to vertically center text and HTML elements with CSS
• Updating CSS Variables with Javascript
• CSS Text
• Creating a Javascript Drawing and Annotation Application
• Putting Javascript in Your CSS with Paint Worklets
• How the CSS Box Model Works
• How to do Deletion Animations with CSS