how to make texture2d grid cells smaller ?

hello,

i try to make a grid plane and i follow some tutorial to do it but i want the size of these squares more smaller and change its size .. how can i do that ??

This is my code :

  void CreateMap()
         {
             mapObject = new GameObject("Map");
             mapRenderer = mapObject.AddComponent<SpriteRenderer>();
 
             mapObject.tag = "element";
             grid = new Node[maxWidth, maxHeight];
 
             Texture2D txt = new Texture2D(maxWidth, maxHeight);
             
             for (int x = 0; x < maxWidth; x++) {
                 for (int y = 0; y < maxHeight; y++)
                 {
                     Vector3 tp = Vector3.zero;
                     tp.x = x;
                     tp.y = y;
 
                     Node n = new Node()
                     {
                         x = x,
                         y = y,
                         worldPosition = tp
                     };
 
                     grid[x, y] = n;
 
                     availableNodes.Add(n);
 
                     if (x % 2 != 0) {
                         if (y % 2 != 0)
                         {
                             txt.SetPixel(x, y, color1);
                         }
                         else {
                             txt.SetPixel(x, y, color2);
                         }
                     }
                     else
                     {
                         if (y % 2 != 0)
                         {
                             txt.SetPixel(x, y, color2);
                         }
                         else
                         {
                             txt.SetPixel(x, y, color1);
                         }
                     }
                 }
             }
 
             txt.filterMode = FilterMode.Point;
             txt.Apply();
             Rect rect = new Rect(0, 0 , maxWidth, maxHeight);
             Sprite sprite = Sprite.Create(txt, rect, Vector2.zero, 1, 0, SpriteMeshType.FullRect);
             mapRenderer.sprite = sprite;
         }

And this is the current result :