Native web-component with shadow-root

A fully functional web-component with shadow-root. It uses the style from 'Codepen'. This way I was able to use SCSS (which made it a bit easier to style the digits 😊)

The component has 2 attributes:

Looks like it is only working instantly in webkit browsers for now 😔
Firefox users need to enable 2 flags in about:config :
dom.webcomponents.shadowdom.enabled
dom.webcomponents.customelements.enabled
Microsoft browser users have some bad luck