The browser as a quasi-operating system, with websites as executable applications - that's how you can view many parts of the Internet nowadays. Even if you have to know quite a lot of programming languages or syntaxes for that, I would say: nowadays it's worth getting into this in depth.
It was not so long ago, when browsers were relatively inflexible, because HTML and CSS had not yet developed very far. When color specifications with alpha values were not yet supported by many browsers. When styling tools like Flexbox or Grid were still completely new and only a few browsers were able to use them properly. But since about 2012, everything has changed for the better.
Fortunately, most browsers nowadays also adhere to the web standards, so you only have to implement browser-specific special rules in rare cases. Especially the success of all those chromium-based browsers is a real blessing for most web developers. If Safari and Firefox now get their respective problems under control, the life of a web developer will become a lot easier - Safari often lags several years behind in terms of development, and Firefox, in contrast to Chromium-based browsers, still requires additional CSS attributes which it could theoretically calculate itself, but it doesn't.
It was not so long ago, when browsers were relatively inflexible, because HTML and CSS had not yet developed very far. When color specifications with alpha values were not yet supported by many browsers. When styling tools like Flexbox or Grid were still completely new and only a few browsers were able to use them properly. But since about 2012, everything has changed for the better.
Fortunately, most browsers nowadays also adhere to the web standards, so you only have to implement browser-specific special rules in rare cases. Especially the success of all those chromium-based browsers is a real blessing for most web developers. If Safari and Firefox now get their respective problems under control, the life of a web developer will become a lot easier - Safari often lags several years behind in terms of development, and Firefox, in contrast to Chromium-based browsers, still requires additional CSS attributes which it could theoretically calculate itself, but it doesn't.