In what way does ⌘+ (Mac) or Ctrl+ (Windows) not satisfy your need? I prefer changing font size that way, because it's simple and works on every site, and I can

In what way does ⌘+ (Mac) or Ctrl+ (Windows) not satisfy your need? I prefer changing font size that way, because it's simple and works on every site, and I can change it depending on whether I'm using a big monitor or not.