Feedback on Main Menu

After asking some UI and UX experts on various Discord servers, the main feedback I received was the X in the top right of the screen, that it should say "Quit" or something clearer instead, and also that the inventory sort options should be at the top and possible something to enable or disable. I tried making a checkbox for the sort combo box, but then realised that the items have to be sorted in some way anyway, so being able to disable the sort doesn't make sense, so I instead set the default selected option to "Date", which will put the most recent items at the top, which is what happens in CS:GO.