Index is now responsive

Finished making the home page, index.php, responsive. The footer now
changes depending on the screen size and if on mobile the social links are
removed. The social section is now also responsive with one going below
the other on tablet and mobile. The contact form is also
responsive with the message being next to other elements untill the size
is mobile like then the form is one after the other. Finally, when the
contact input field is active it has an orange border to match the rest of
the colour scheme.

* Finished the responsive part of the index.php
* Updated the contact form to have border when field is active.
* Changed the style of the send button so the font is now styled correctly