On desktop, the border and dark header bar around a tool make it clear where “the tool” begins and ends. On a phone screen, though, that same chrome was just eating into already-limited space.
So on mobile we removed the border and header bar and trimmed the side padding, letting the actual tool content stretch across more of the screen. Inputs and results now get more room, which should mean less scrolling for tools with tables or charts. Sections that don’t make sense without a keyboard, like the shortcuts list, are hidden on mobile too. Desktop and tablet layouts are unchanged.
For tools where the header bar held something essential, like a print or export button, we kept just that button and moved it above the content so it’s still there on mobile.