design for tiny internal web tool

Description

Hi,
I need a simple design + HTML/CSS for an internal tool. I'm a programmer, I can make things work well, but I can't make them look nice. But you can :)
It's a tiny internal website which is used to build some projects. There are 3 pages I need, which I will describe and give you wireframes of, and you deliver them as HTML/CSS, and I can go from there. The audience for the website is technical, and it doesn't need to look flashy, just look nice.
Some technical requirements: - CSS + HTML only, no javascript(!), no external web fonts(!), but you can use any modern CSS as long as the end result works in the latest Firefox - ideally CSS grid based (that's easiest to change things for me later) - it's an internal project, but it'll end up open source (MIT licensed) - I don't have any particular color scheme or theme in mind, you're free to do your thing
Summary: I describe 3 pages, you deliver them in HTML/CSS, but do note the requirements