Please help me understand the methodology behind the hot spots, especially for defense. Are the rankings solely done by avg amount of points given up by opposing defenses? I'm specifically looking at Chicago. Detroit is colored light green for a good matchup even though they were just 3-point favorites at Chicago and will probably be 6+ point favorites when they play in Detroit week 15. The Eagles are a neutral matchup even though they're currently favored by 12.5 at home against Chicago. It just doesn't seem right. I'd think they should show up as the brightest, boldest, most dangerous red. I'm not second-guessing or criticizing, just want to better understand what goes into matchup evaluations. Thanks.