Changing board backgrounds, Trello

To change your board's background, go to the board menu on the right side of your board, and select "Change Background"

Card Colors for Trello

How can I set another background for a board and upload my company's logo? - Kanbanchi

Trello Backgrounds: 7 awesome free illustrations to change up your Trello Boards - Mixkit

Trello's demo Kanban board

Hack Trello for a Better User Experience

Be Yourself at Work: How to Customize Your Trello Board

How To Make Your Trello Boards Visually Appealing - Bloom Hustle Grow

Trello Series How to Change your Board Background Image

customization - How to change colors for different boards in Trello.com? - Web Applications Stack Exchange

16 Free Trello Templates for Every Sort of Team - Blue Cat Reports