[envs-team]new Website update

hey forks,

our website has a fresh update : D

first of all, many thanks to ~slatian for your work! The update looks really great and works great. Thank you very much for that <3

the changes contains a new stylesheet and html structure for envs.net that:

* is responsive * adds an theme mode (light and dark(default)) based of your browser settings * won't break existing sites still using the old stylesheet, header and footer