import 'dart:ui'; extension ColorExtension on Color { Color darken([int percent = 40]) { assert(1 <= percent && percent <= 100); final value = 1 - percent / 100; return Color.from( alpha: a, red: r * value, green: g * value, blue: b * value, ); } Color lighten([int percent = 40]) { assert(1 <= percent && percent <= 100); final value = percent / 100; return Color.from( alpha: a, red: r + ((1 - r) * value), green: g + ((1 - g) * value), blue: b + ((1 - b) * value), ); } Color avg(Color other) { return Color.from( alpha: (a + other.a) / 2, red: (r + other.r) / 2, green: (g + other.g) / 2, blue: (b + other.b) / 2, ); } }