No-Library (pure JS), HTML, CSS, JavaScript
jQuery 2.1.0, HTML, CSS, JavaScript
A blank canvas to play / experiment with RxJS: https://github.com/Reactive-Extensions/RxJS
Footer flex box
Use window properties and user agent string to detect the browser name.
Pulsing circle
Heatmap colors table
https://stackoverflow.com/a/60566693/1697459