404, There isn't a GitHub Pages site here.

[TLKG]

Clicked on the demo and source button go err 404 msg. Here is the URL, tried both .io and .com resulting the same:
http://jonthornton.github.com/Datepair.js

[cosky5]

Open the repository and check out the settings and edit "Custom Domain" and save it
You can also check this link:
https://help.github.com/articles/adding-or-removing-a-custom-domain-for-your-github-pages-site/

[kingsleykbc]

kingsleykbc.github.io

[gurungsuraaj]

.