I know that there are a lot of addons for browsers available which let you edit the CSS. Even the stock Inspector lets you do that.
What I am looking for is a way to edit the CSS values in the browser with either dedicated up/down buttons, the up/down keyboard keys or with the mouse scroll wheel.
Why?
I want to change width, height, padding, margin .... not by typing in the number, but by clicking/pressing up/down buttons/keys to change the value, or simply with the mouse wheel.
I would prefer to see the changes in real time, so when I scroll up the mouse wheel for let's say margin-left, the element on the page should move in realtime according to the changes.
But I would also accept a solution which requires pressing some kind of refresh button first in order to see the changes. The most important thing though is to not having to type in the values, but change them by buttons or by mouse wheel.