Screenshots

Windows application, the main view in Dark mode with all elements present:

Linux application, the main view in Light mode with the memory panel collapsed/hidden:

Windows application, the main view in Light mode with the memory buttons row hidden; Memory and History appear as tabs at the bottom of the main view.

Windows application, the main view in Dark mode without main menu and Result box. The bottom panel is the list of functions.

Windows application, the main view in Light mode with a 3-row expression editor and the keypad in Programmer's layout.