{"input":{"lat":60,"lon":0},"mercator":{"linear_scale":2,"area_scale":4,"explanation":"Mercator linear scale = sec(phi); area scale = sec(phi)^2. At the equator both equal 1.0. At 60° N/S, linear=2x, area=4x. At 80°, area≈33x."},"meta":{"source":"https://truesize-map.vercel.app/","docs":"https://truesize-map.vercel.app/#api"}}