How to set y-axis limits to mouselook script

I'm using this as a mouselook script, works perfectly except for if the mouse is put to the bottom or top of the screen - it can loop all the way around.

 var sensibility : float;
 function Start () {
  
 }
  
 function Update () {
         transform.Rotate(Vector3(0,Input.GetAxis("Mouse X")*sensibility,0), Space.World);
         transform.Rotate(Vector3(-Input.GetAxis("Mouse Y")*sensibility,0,0));
  
 }

How would I set a limit to ~-80 and 90 degrees?