Learning HTML and CSS and maybe later JavaScript. Building a mockup online-resume is a good way to learn all the basis
Basically, it's just a sandbox to learn.
My code is dirty and amateur, don't hesitate to give me advice or to correct anything I do wrong.
You can have a quick demo here: xxxxxxx (Please try it on smartphone, tablet and desktop computer to see the responsive magic. And on desktop, change the width of the browser window ;-) )
Ok, let's get started