private func layoutFillColor() {
        if level >= 0 && level <= 100 {

            switch level {
            case 0...lowThreshold:
                levelFill.backgroundColor = lowLevelColor.cgColor
            case lowThreshold...mediumThreshold:
                levelFill.backgroundColor = mediumLevelColor.cgColor
            case mediumThreshold...100:
                levelFill.backgroundColor = highLevelColor.cgColor
            default: break
            }

            terminalOpening.backgroundColor = (backgroundColor ?? .white).cgColorß
        } else {
            levelFill.backgroundColor = noLevelColor.cgColor
            terminalOpening.backgroundColor = noLevelColor.cgColor
        }
    }