2. HTML. We write HTML in files that end with the .html extension (like homepage.html).. To write HTML and CSS code, you’ll want to install a code editor.Nowadays, one of the most popular free ...

jsFiddle is the perfect solution; it provides a custom environment (based on user selections) to test (or fiddle with) your JavaScript, HTML, and CSS code right inside your browser.

The CSS code modifies the PayPal button slightly, centering it on the page without changing its functionality. Open the HTML source code of the Web page that contains your PayPal button in a text ...