Nikola Đuza lays out a way you can customize your README to stand out from the crowd:

GitHub supports adding HTML in Markdown, but it is pretty aggressive when removing HTML that can be potentially dangerous to users. Things like scripts, iframes, and similar will get removed or “silenced” to avoid malicious content from being served to users.

Luckily, there’s one way to sneak in some HTML (or a web page) inside the README. You can do it via SVG and foreignObject SVG element.