Background custom colors

Increase the color palette of backgrounds.

Black

Indigo

Orange

Pink

Purple

Teal

<!-- Source -->
<div class="bg-black"></div>
<div class="bg-indigo"></div>
<div class="bg-orange"></div>
<div class="bg-pink"></div>
<div class="bg-purple"></div>
<div class="bg-teal"></div>