Adam Wathan & Steve Schoger, full stack developer, who are facing the design problem. They shows how amazing way to refactor UI without design skill in thier "7 Practical Tips for Cheating at Design" article.
Another good arcticle from Adam Wathan & Steve Schoger for redesigning application UI in Laravel forum website via their article, Redesigning Laravel.io.
Fundamental Design for web via Before you can master design, you must first master the fundamentals
This article talks about 4 fundamentals
Go back to the basics with type
Use space to create balance
Use size to establish visual hierarchy
Use color to convey meaning
Other interesting stuff about design