The show is based on the saying and classic children's programme competition entry procedure before the internet where you would send your answer on the reverse of a sealed envelope.
The dictionary refers to the saying as :-
back-of-the-envelope in British English
(of a plan, calculation, etc) composed or performed quickly and without detailed analysis or research
Word origin from the notion of something being hastily written on the back of an envelope in the absence of other writing materials
(on the) back of an envelope
planning or calculating something in a way that is not detailed, exact or complete
We added up our savings on the back of an envelope.
This epidemic has provided us with the nearest we are ever going to get to hitting the reset button in our life times. A new start, a fresh beginning. Where do we go from here? What would you like changed?
This could be a personal, social, global, political, environmental beginning or any other way you wish to express our chance to make a new world order.
It could take the form of a drawing or text or equation or painting or any other media that fits on the back of an envelope.
They can be comical, serious, political, satirical or again any other way you want to approach question of a new start.