Common CSS rule for all
As you’ve already seen, CSS doesn’t work the same with all browsers. The best known are Edge, FireFox, Chrome, Opera and Safari. There are others but very few.
Each browser has their own CSS interpreter. Despite the fact that W3C offers a standard for CSS rules, editors are still protective of their applications and make the task longer for site developers.
Fortunately, this only affects a few CSS rules. Those added from CSS 2.0, 3.0 etc.