bootstrap mobile navigation broken on last page

Hi

On mobile view on my GUIDES page my bootstrap navigation background isn't getting to the bottom of my navigation menu?! please help!
https://drive.google.com/file/d/1BYT0-RgqNX19YDGhNYypm-b7wteqTmD0/view?usp=sharing

Here is my website
http://mosaic-table-co.stackstaging.com/guides/