How to use the raylib.DARKGRAY function in raylib

// TODO: Update your variables here
  //----------------------------------------------------------------------------------

  // Draw
  //----------------------------------------------------------------------------------
  r.BeginDrawing()

  r.ClearBackground(r.RAYWHITE)

  console.log('hello')

  r.GetKeyPressed()
  console.log(r.IsKeyDown(r.KEY_ONE))

  // console.log(r.GetKeyPressed())
  r.DrawText('some basic shapes available on raylib', 20, 20, 20, r.DARKGRAY)

  var position = {
    x: 100,
    y: 100,
  }
  var size = {
    x: 200,
    y: 150,
  }
  r.DrawRectangleV(position, size, r.DARKBLUE)

  r.DrawRectangleRec(
    {
      x: 50,
      y: 50,
      width: 50,

r.DrawLine(-screenWidth*10, camera.target.y, screenWidth*10, camera.target.y, r.GREEN);

    r.EndMode2D();

    r.DrawText("SCREEN AREA", 640, 10, 20, r.RED);

    r.DrawRectangle(0, 0, screenWidth, 5, r.RED);
    r.DrawRectangle(0, 5, 5, screenHeight - 10, r.RED);
    r.DrawRectangle(screenWidth - 5, 5, 5, screenHeight - 10, r.RED);
    r.DrawRectangle(0, screenHeight - 5, screenWidth, 5, r.RED);

    r.DrawRectangle( 10, 10, 250, 113, r.Fade(r.SKYBLUE, 0.5));
    r.DrawRectangleLines( 10, 10, 250, 113, r.BLUE);

    r.DrawText("Free 2d camera controls:", 20, 20, 10, r.BLACK);
    r.DrawText("- Right/Left to move Offset", 40, 40, 10, r.DARKGRAY);
    r.DrawText("- Mouse Wheel to Zoom in-out", 40, 60, 10, r.DARKGRAY);
    r.DrawText("- A / S to Rotate", 40, 80, 10, r.DARKGRAY);
    r.DrawText("- R to reset Zoom and Rotation", 40, 100, 10, r.DARKGRAY);

  r.EndDrawing();
  //----------------------------------------------------------------------------------
}

// De-Initialization
//--------------------------------------------------------------------------------------
r.CloseWindow();        // Close window and OpenGL context
//--------------------------------------------------------------------------------------

if (r.IsKeyPressed(r.KEY_R))
  {
      camera.zoom = 1.0
      camera.rotation = 0
  }
  //----------------------------------------------------------------------------------

  // Draw
  //----------------------------------------------------------------------------------
  r.BeginDrawing();

    r.ClearBackground(r.RAYWHITE);

    r.BeginMode2D(camera);

      r.DrawRectangle(-6000, 320, 13000, 8000, r.DARKGRAY);

      for (var i = 0; i < MAX_BUILDINGS; i++) {
        r.DrawRectangleRec(buildings[i], buildColors[i]);
      }

      r.DrawRectangleRec(player, r.RED);

      r.DrawLine(camera.target.x, -screenHeight*10, camera.target.x, screenHeight*10, r.GREEN);
      r.DrawLine(-screenWidth*10, camera.target.y, screenWidth*10, camera.target.y, r.GREEN);

    r.EndMode2D();

    r.DrawText("SCREEN AREA", 640, 10, 20, r.RED);

    r.DrawRectangle(0, 0, screenWidth, 5, r.RED);
    r.DrawRectangle(0, 5, 5, screenHeight - 10, r.RED);

r.DrawCube(r.Vector3(0, 2.5, 16), 32, 5, 1, r.GOLD);      // Draw a yellow wall

            // Draw some cubes around
            for (let i = 0; i < MAX_COLUMNS; i++)
            {
                r.DrawCube(positions[i], 2, heights[i], 2, colors[i]);
                r.DrawCubeWires(positions[i], 2, heights[i], 2, r.MAROON);
            }

        r.EndMode3D();

        r.DrawRectangle( 10, 10, 220, 70, r.Fade(r.SKYBLUE, 0.5));
        r.DrawRectangleLines( 10, 10, 220, 70, r.BLUE);

        r.DrawText("First person camera default controls:", 20, 20, 10, r.BLACK);
        r.DrawText("- Move with keys: W, A, S, D", 40, 40, 10, r.DARKGRAY);
        r.DrawText("- Mouse move to look around", 40, 60, 10, r.DARKGRAY);

    r.EndDrawing();
    //----------------------------------------------------------------------------------
}

// De-Initialization
//--------------------------------------------------------------------------------------
r.CloseWindow();        // Close window and OpenGL context
//--------------------------------------------------------------------------------------

ballColor = r.LIME
    }
    else if (r.IsMouseButtonPressed(r.MOUSE_RIGHT_BUTTON)) {
        ballColor = r.DARKBLUE
    }
    //----------------------------------------------------------------------------------

    // Draw
    //----------------------------------------------------------------------------------
    r.BeginDrawing()

        r.ClearBackground(r.RAYWHITE)

        r.DrawCircleV(ballPosition, 40, ballColor)

        r.DrawText("move ball with mouse and click mouse button to change color", 10, 10, 20, r.DARKGRAY)

    r.EndDrawing()
    //----------------------------------------------------------------------------------
}

// De-Initialization
//--------------------------------------------------------------------------------------
r.CloseWindow()        // Close window and OpenGL context
//--------------------------------------------------------------------------------------

// Draw some cubes around
            for (let i = 0; i < MAX_COLUMNS; i++)
            {
                r.DrawCube(positions[i], 2, heights[i], 2, colors[i]);
                r.DrawCubeWires(positions[i], 2, heights[i], 2, r.MAROON);
            }

        r.EndMode3D();

        r.DrawRectangle( 10, 10, 220, 70, r.Fade(r.SKYBLUE, 0.5));
        r.DrawRectangleLines( 10, 10, 220, 70, r.BLUE);

        r.DrawText("First person camera default controls:", 20, 20, 10, r.BLACK);
        r.DrawText("- Move with keys: W, A, S, D", 40, 40, 10, r.DARKGRAY);
        r.DrawText("- Mouse move to look around", 40, 60, 10, r.DARKGRAY);

    r.EndDrawing();
    //----------------------------------------------------------------------------------
}

// De-Initialization
//--------------------------------------------------------------------------------------
r.CloseWindow();        // Close window and OpenGL context
//--------------------------------------------------------------------------------------

// Main game loop
while (!r.WindowShouldClose())    // Detect window close button or ESC key
{
    // Update
    //----------------------------------------------------------------------------------
    // TODO: Update your variables here
    //----------------------------------------------------------------------------------

    // Draw
    //----------------------------------------------------------------------------------
    r.BeginDrawing();

        r.ClearBackground(r.RAYWHITE);

        r.DrawText("some basic shapes available on raylib", 20, 20, 20, r.DARKGRAY);

        var position = {
            x: 100,
            y: 100
        }
        var size = {
            x: 200,
            y: 150
        }
        r.DrawRectangleV(position, size, r.DARKBLUE)

        r.DrawRectangleRec({
            x: 50,
            y: 50,
            width: 50,
            height: 50