Mobile Input Touch Tag Unaffected

Nothing happens when I touch anything tagged below -

 void Update () {
     ray = Camera.main.ScreenPointToRay(Input.mousePosition);
     
     if(Physics.Raycast(ray,out hit, Mathf.Infinity) && Input.GetMouseButtonDown (0))
     {
         
         if(hit.collider.gameObject.tag == "Background")
         {
             print("Touched");
         }
     }
 }

Also need it for mobile, but I can't get it to work with mouse.