C# game over arcanoid brickout game

class Ball
    {
        public int x;
        public int y;
        public int vx = 3;
        public int vy = 3;
        public int r;
        public Graphics gf;
        public Game game;
        public SolidBrush myColor;
        public Ball(int x,int y,int vx,int vy,int r,Graphics gf,Game game) 
        {
            this.x = x;
            this.y = y;
            this.vx = vx;
            this.vy = vy;
            this.r = r;
            this.gf = gf;
            this.game = game;
            myColor = new SolidBrush(Color.IndianRed);
        }
        public void Draw()
        {
            this.gf.FillEllipse(myColor, x, y, r, r);
        }
        public void Move()
        {
            this.x += this.vx;
            this.y += this.vy;
            if(this.x <= 0 || this.x > game.ClientSize.Width - r)
            {
                Random rnd = new Random();
                int r = rnd.Next(0, 256);
                int g = rnd.Next(0, 256);
                int b = rnd.Next(0, 256);
                SolidBrush guyn = new SolidBrush(Color.FromArgb(255, r, g, b));
                this.myColor = guyn;
                vx *= -1;
            }
            if(this.y <= 0)
            {
                Random rnd = new Random();
                int r = rnd.Next(0, 256);
                int g = rnd.Next(0, 256);
                int b = rnd.Next(0, 256);
                SolidBrush guyn = new SolidBrush(Color.FromArgb(255, r, g, b));
                this.myColor = guyn;
                this.vy *= -1;
            }
            this.Draw();
        }

        public bool hits(Board board)
        {
            int x1 = this.x + this.r / 2;
            int x2 = board.x + board.w / 2;
            int y1 = this.y;
            int y2 = board.y;
            int y_dist = Math.Abs(y1 - y2);
            int x_dist = Math.Abs(x1 - x2);
            if(y_dist <= r/2 + board.h/2 && x_dist <= board.w/2 + r / 2)
            {
                return true;
            }
            else
            {
                return false;
            }  
        }
    }


class Board
    {
        public int x;
        public int y;
        public int w;
        public int h;
        public Graphics gf;
        public Game game;
        public SolidBrush MyColor;
        public Board(int x, int y, int w, int h, Graphics gf, Game game)
        {
            this.x = x;
            this.y = y;
            this.w = w;
            this.h = h;
            this.gf = gf;
            this.game = game;
            MyColor = new SolidBrush(Color.Black);
        }
        public void draw()
        {
            gf.FillRectangle(MyColor, x, y, w, h);
        }

        public void gna(string v)
        {

            if (v == "left" && x > 0)
            {
                this.x -= 10;
            }
            else if (v == "right" && x < this.game.ClientSize.Width - 85)
            {
                this.x += 10;
            }
            this.draw();
        }
    }


public partial class Game : Form
    {
        Graphics gf;
        Ball ball;
        Board board;
        public Game()
        {
            InitializeComponent();
            this.gf = this.CreateGraphics();
            this.board = new Board(this.ClientSize.Width / 2 - 40, this.ClientSize.Height - 60, 80, 20,gf,this);
            this.ball = new Ball(this.ClientSize.Width / 2 - 10, this.ClientSize.Height/2 - 10, 3, 3, 20, gf, this);
        }

        private void Game_Paint(object sender, PaintEventArgs e)
        {
            this.board.draw();
            this.ball.Draw();
        }

        private void Game_KeyDown(object sender, KeyEventArgs e)
        {
            switch (e.KeyCode)
            {
                case Keys.Left:
                case Keys.A:
                    this.board.gna("left");
                    break;
                case Keys.Right:
                case Keys.D:
                    this.board.gna("right");
                    break;

            }
        }

        private void timer1_Tick(object sender, EventArgs e)
        {
            this.gf.FillRectangle(Brushes.White, 0, 0, this.ClientSize.Width, this.ClientSize.Height);
            this.board.draw();
            this.ball.Draw();
            this.ball.Move();
            if (this.ball.hits(this.board))
            {
                Random rnd = new Random();
                int r = rnd.Next(0, 256);
                int g = rnd.Next(0, 256);
                int b = rnd.Next(0, 256);
                SolidBrush guyn = new SolidBrush(Color.FromArgb(255, r, g, b));
                this.ball.myColor = guyn;
                this.board.MyColor = guyn;
                this.ball.vy *= -1;
            }
        }

    }