I need some help please!

Have a Spreadsheet with a few columns, I want to add conditional formatting to column H which consist of Response times for instance
10
05:27
06:18
46
24
46
49
> 3day!!!
05:03
> 1day!!!
> 6day!!!
I want to mark anything that is under 4 hours in green, and anything above 4 hours below 17 hours with a purple, and the rest in red, how do I do this?