Websites often go through redesigns to keep them looking “fresh”, changing colours, backgrounds, layouts and more. Which is fine, if you wanted something new – but not so great if you were happier before.

Stylish is a free browser extension for Chrome, Firefox, Opera and Safari which uses custom CSS code to restyle websites, changing colours, replacing fonts, dropping content and generally improving their look and feel.

Getting started is as easy as visiting your target site, clicking the Stylish icon and selecting “Find more styles for this site”.

You’ll then see a list of available themes, a text description and thumbnail preview of each, and details including its upload date, the number of downloads so far, user rating and more. (Check out userstyles.org to see what’s available.)

Website themes can be browsed, updated or edited from the Stylish console

If you like something, click it, select Install with Stylish > OK, and you’re done. Revisit the page and you’ll probably see the new look immediately (reload it, if not).

Stylish isn’t just about revamping individual sites. It also supports “global” styles to modify how all websites are displayed, perhaps changing colours or replacing fonts to make them more readable.

Browse and install as many site-specific or global themes as you like. We found these conflicted occasionally – or just didn’t work at all – but you can view, update or remove individual themes later from the Stylish management console.

Alternatively, if you think a theme just needs a minor tweak, an Edit option allows you to customise it further by editing the underlying CSS code.

You’ll need a basic knowledge of CSS if you want to do anything significant, but fortunately there’s some documentation on the developer’s site.

Stylish also has a very helpful forum. Post a question there giving full details of what you’re trying to do, and any problems you’re seeing, and there’s a good chance someone will post the necessary code.

Stylish is a free browser extension for Chrome, Firefox, Opera and Safari.