Writr Theme – Changing Background Color On Homepage

Hello!

I made a Writr Child Theme and I’m trying to change the entire background color to dark grey (#303030) for the content area of the homepage only.

This is the website I’m working on: https://www.rellevantmusic.com/

So far I’ve entered the CSS below and it’s only changed the background of part of the area. There are still white boxes at the top and bottom, and I’m having a hard time targeting the names of these containers.

body#homepage div#primary.content-area,
body#homepage h1.entry-title {
background: #303030;
color: #303030;
}

I also want to get rid of the little white triangle next to the entry title, but also only for the homepage.

Please help! I’d truly appreciate it. I’ve spent too much time trying to figure it out.