具有十六进制或RGB的一种颜色代码。保持这个为基础，需要产生较亮和较暗的渐变颜色基于百分比在C#

using System;

public class ColorGradient
{
    public static string GetLighterColor(string colorCode, int percentage)
    {
        // 解析颜色代码
        int red = Convert.ToInt32(colorCode.Substring(0, 2), 16);
        int green = Convert.ToInt32(colorCode.Substring(2, 2), 16);
        int blue = Convert.ToInt32(colorCode.Substring(4, 2), 16);

        // 调整颜色亮度
        red = AdjustColorComponent(red, percentage);
        green = AdjustColorComponent(green, percentage);
        blue = AdjustColorComponent(blue, percentage);

        // 生成新的颜色代码
        string newColorCode = $"{red:X2}{green:X2}{blue:X2}";

        return newColorCode;
    }

    public static string GetDarkerColor(string colorCode, int percentage)
    {
        // 解析颜色代码
        int red = Convert.ToInt32(colorCode.Substring(0, 2), 16);
        int green = Convert.ToInt32(colorCode.Substring(2, 2), 16);
        int blue = Convert.ToInt32(colorCode.Substring(4, 2), 16);

        // 调整颜色亮度
        red = AdjustColorComponent(red, -percentage);
        green = AdjustColorComponent(green, -percentage);
        blue = AdjustColorComponent(blue, -percentage);

        // 生成新的颜色代码
        string newColorCode = $"{red:X2}{green:X2}{blue:X2}";

        return newColorCode;
    }

    private static int AdjustColorComponent(int component, int percentage)
    {
        // 调整颜色亮度
        double factor = 1 + (percentage / 100.0);
        component = (int)Math.Round(component * factor);

        // 确保颜色分量在有效范围内
        component = Math.Max(0, Math.Min(255, component));

        return component;
    }
}

public class Program
{
    public static void Main(string[] args)
    {
        string colorCode = "FF0000"; // 红色

        string lighterColor = ColorGradient.GetLighterColor(colorCode, 20);
        string darkerColor = ColorGradient.GetDarkerColor(colorCode, 20);

        Console.WriteLine($"Lighter Color: #{lighterColor}");
        Console.WriteLine($"Darker Color: #{darkerColor}");
    }
}