At some point, every curious web designer comes across the CSS Zen Garden: a shrine to the power of CSS, a web technology that helps separate your design from your content.
By clicking on the names of different themes, the same page is loaded again again, each time with an entirely different look and feel. It gives you a concept of how versatile CSS can be in the hands of expert web developers. So while the text of the page stays the same, the look of it drastically changes. Anyone can submit a new theme to the gallery.
CSS stands for Cascading Style Sheets, and it’s a way of building a web page where you assign each element a style that dictates how it should look in a web browser. The general idea is that you can have an .html file which contains your words/content and a .css file that contains your layout/appearance. That way you can edit the two independently. One benefit is that you can change the way an entire site looks by changing only one file (new school), instead every file on the site (old school). Another great thing about it: it can greatly simplify the code of the page, making it much easier for search engines and vision-impaired visitors to understand what you’re all about.