I think the easiest way to collect the Lego pieces from the floor is by using a vacuum cleaner.
Then look at the sorting as a separate problem :)
Then look at the sorting as a separate problem :)
From the item description: "TIDY UP IN SECONDS: Say goodbye to messy playrooms with our storage organizer! The play mat provides a dedicated area for creative play, and when it's time to pack up, simply gather the handles and tip everything back into the compact storage cube. "