See demo on Codepen: https://codepen.io/comehope/pen/PdMyJd
Watch interactive video on Scrimba: https://scrimba.com/p/pEgDAM/c648Nu7
Read annotated source on Segmentfault(zh-cn): https://segmentfault.com/a/1190000016530200
Inspired by: Fabio Ottaviani https://codepen.io/supah/pen/VaYdwb