Log score 10→0 with color zones.
score = 10 × log(high / price) / log(high / low)
score = 1 + 9 × log(high / price) / log(high / low)
price × (high / low)^(3 / (10 - topScore))
price ÷ (high / low)^(3 / (10 - topScore))
price × (high / low)^(3 / (10 - topScore))
price ÷ (high / low)^(3 / (10 - topScore))