Edit: This one took me three takes, I started in India, made my way to the Arabian Peninsula, and headed down to Africa.
I get that you want cold to hot, and red is hot and white is cold, but I find the warmest three shades not all that easy to distinguish, especially when a county is tiny. I would put in a country and then have to spend a lot of time trying to determine if the shade was lighter, darker, or the same. Not efficient for beating the clock.
In my opinion, using the rainbow, or at least more than just red, might help us to make quicker decisions about whether something is closer or further away.
Typed Pakistan and then South Africa.. then the mystry country
Never gonna pull that off again