[Difference Between Codepen and Browser]

Thanks for your help

I only tested it in firefox, turns out that's the problem

[Difference Between Codepen and Browser]

Hi

I coded this animated boombox in notepad++ and when the dragger at the bottom is dragged the width of the slider should increase, like in the image below. It works perfectly in my browser but when I put the same code in codepen the width updates as its supposed to but the slider never animates.

 

Is this a codepen issue?

or is there something I've left out that is causing this?

Thanks

See the Pen jdYBJo by inksplatwebdesign (@inksplatwebdesign) on CodePen