Results Summary Component

While building my project, l encounted some few difficulties that l would want anyone with any solution can help me out. But hope using a different color for my summary part isnt bad ? l could not fine the right background-color so l decided to use my own preffered color.

       CHALLENGES

1. How do you set width on a container ? Should l use max-width or the width.
2. Must l set height on my container since content inside of my tags will automatically adjust to fill my container. ( Resource to any site will be very helpful as well ) .