Each individual Internet browser works by using a layout engine to render World-wide-web pages, and support for CSS features just isn't consistent amongst them. Due to the fact browsers will not parse CSS correctly, various coding techniques are created to target distinct browsers with workarounds (generally known as CSS hacks https://www.presta-addons-modules.com/en/seo/prestashop-seo-friendly-url-pretty-url-without-id-number.html