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 Transformations
• Creating 3D CSS Buttons which Move as you Mouse Over
• CSS Pseudo Elements
• Making a CSS Only Minecraft Chicken
• How to make a child element appear behind its parent in CSS
• CSS States
• CSS Transitions
• CSS Inset Borders at Varying Depths
• A Complete Guide to How the CSS not Selector Works
• How to Create Animated Cards with WebGL and Three.js