XF 1.5 What is this area called?

[CREATE Buzz]

Hey troops,

For the life of me I can't figure out the name of this area in a thread so that I can change the background color to ffffff. Thank you in advance for your help!

 

[Paul B]

This set of guides may help: https://xenforo.com/community/resources/how-to.4390/

 

[CREATE Buzz]

Awesome, thanks Brogan. Baptism by fire into code, but I figured it out.