Class1.cs

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Windows.Forms;

class RoundedButton : Button
{
    private int roundRadius = 20;
    private float buttonOpacity = 1.0f; // Прозрачность кнопки (от 0 до 1)
    private Color buttonBackColor = Color.LightBlue; // Начальный цвет фона
    private float borderTickness = 1.75f;
    private Color borderColor = Color.CadetBlue;

    public int RoundRadius
    {
        get { return roundRadius; }
        set
        {
            roundRadius = value;
            this.Invalidate(); // Перерисовать кнопку при изменении радиуса
        }
    }

    public float ButtonOpacity
    {
        get { return buttonOpacity; }
        set
        {
            buttonOpacity = Math.Min(1, Math.Max(0, value)); // Ограничиваем значение от 0 до 1
            this.Invalidate(); // Перерисовать кнопку при изменении прозрачности
        }
    }

    public Color ButtonBackColor
    {
        get { return buttonBackColor; }
        set
        {
            buttonBackColor = value;
            this.Invalidate(); // Перерисовать кнопку при изменении цвета фона
        }
    }

    public float BorderTickness
    {
        get { return borderTickness; }
        set
        {
            borderTickness = value;
            this.Invalidate();
        }
    }

    public Color BorderColor
    {
        get { return borderColor; }
        set 
        {
            borderColor = value;
            this.Invalidate();
        }
    }

    private GraphicsPath GetRoundPath(RectangleF rect, int radius)
    {
        float r2 = radius / 2f;
        GraphicsPath graphPath = new GraphicsPath();
        graphPath.AddArc(rect.X, rect.Y, radius, radius, 180, 90);
        graphPath.AddLine(rect.X + r2, rect.Y, rect.Width - r2, rect.Y);
        graphPath.AddArc(rect.X + rect.Width - radius, rect.Y, radius, radius, 270, 90);
        graphPath.AddLine(rect.Width, rect.Y + r2, rect.Width, rect.Height - r2);
        graphPath.AddArc(rect.X + rect.Width - radius, rect.Y + rect.Height - radius, radius, radius, 0, 90);
        graphPath.AddLine(rect.Width - r2, rect.Height, rect.X + r2, rect.Height);
        graphPath.AddArc(rect.X, rect.Y + rect.Height - radius, radius, radius, 90, 90);
        graphPath.AddLine(rect.X, rect.Height - r2, rect.X, rect.Y + r2);
        graphPath.CloseFigure();
        return graphPath;
    }

    protected override void OnPaint(PaintEventArgs e)
    {
        base.OnPaint(e);
        RectangleF rect = new RectangleF(0, 0, this.Width, this.Height);
        using (GraphicsPath graphPath = GetRoundPath(rect, roundRadius))
        {
            this.Region = new Region(graphPath);

            // Применяем прозрачность к цвету фона
            Color transparentButtonBackColor = Color.FromArgb((int)(buttonOpacity * 255), buttonBackColor);

            using (Brush brush = new SolidBrush(transparentButtonBackColor))
            {
                e.Graphics.FillPath(brush, graphPath);
            }

            
            if (borderColor != this.BackColor)
                using (Pen pen = new Pen(borderColor, borderTickness))
                {
                    pen.Alignment = PenAlignment.Inset;
                    e.Graphics.SmoothingMode = SmoothingMode.AntiAlias;
                    e.Graphics.DrawPath(pen, graphPath);
                }
        }
    }
}

class ColoredCheckBox : CheckBox
{
    public Color CheckmarkColor { get; set; } = Color.Black; // Цвет галочки

    protected override void OnPaint(PaintEventArgs pevent)
    {
        base.OnPaint(pevent);

        // Очищаем текущий фон
        pevent.Graphics.Clear(this.BackColor);

        // Определяем прямоугольники для галочки и текста
        Rectangle checkBoxRect = new Rectangle(0, (this.Height - 16) / 2, 16, 16);
        Rectangle textRect = new Rectangle(20, 0, this.Width - 20, this.Height);

        // Рисуем фон чекбокса
        ControlPaint.DrawCheckBox(pevent.Graphics, checkBoxRect,
            this.Checked ? ButtonState.Checked : ButtonState.Normal);

        // Рисуем галочку при необходимости
        if (this.Checked)
        {
            using (Pen pen = new Pen(CheckmarkColor, 2))
            {
                Point start = new Point(checkBoxRect.Left + 3, checkBoxRect.Top + 9);
                Point middle = new Point(checkBoxRect.Left + 7, checkBoxRect.Bottom - 4);
                Point end = new Point(checkBoxRect.Right - 3, checkBoxRect.Top + 4);

                pevent.Graphics.DrawLine(pen, start, middle);
                pevent.Graphics.DrawLine(pen, middle, end);
            }
        }

        // Рисуем текст
        TextRenderer.DrawText(pevent.Graphics, this.Text, this.Font, textRect, this.ForeColor);
    }
}