Hardware for LED light bar

I'm researching options for a project. I need 4 LED light bars, roughly 26" wide x 3" tall. The light bars need to indicate a percentage, and I need to programmatically set the color. After searching around, it looks like I'll need to rely on combining multiple LED matrices to achieve the effect. Anyone familiar with suitable LED hardware, and how to drive it? (btw, I'm only familiar with Arduino UNO). Thanks XD

Rough diagram:

An Arduino Uno should be able to able to handle this. I'd look around the forums to see what people are using for driving LEDs. Maybe in the LED subsection.

Was mainly interested in what actual LED components (strips, matrices, etc) people are aware of. Most of what I'm seeing are too small. Have any recommendations?