Rotating Blender object using mouse click

Dear all,

Apologies if this is a duplicated post. I just started on Unity.

I imported a Blender object and trying to rotate on x and y axis using mouse click. Essentially user click and hold the left button and can rotate the object horizontally and vertically. I manage to make it work with rotation however the rotation happening anywhere in the screen.

I want the rotation should happen only if user clicks and holds on the object.

Here is my code.

 #pragma strict
 
 //How quickly to rotate the object.
 var sensitivityX:float = 15;
 var sensitivityY:float = 15;
     
 //Camera that acts as a point of view to rotate the object relative to.
 var referenceCamera:Transform;
 
 //The script in Start() is executed before Update(), so we can use it to
 //doublecheck our variables have valid values before we try to run the script in Update().
 function Start() {
     Debug.Log("CupMovementWithMouseClick Start");
     initialColor = renderer.material.color;    
     
     //Ensure the referenceCamera variable has a valid value before letting this script run.
     //If the user didn't set a camera manually, try to automatically assign the scene's Main Camera.
     if (!referenceCamera) {
         if (!Camera.main) {
             Debug.LogError("No Camera with 'Main Camera' as its tag was found. Please either assign a Camera to this script, or change a Camera's tag to 'Main Camera'.");
             Destroy(this);
             return;
         }
         referenceCamera = Camera.main.transform;
     }
 }
             
 //Update() is called once every frame, and should be used to run script that
 //should be doing something constantly. In this case, we potentially want to
 //rotate the object constantly if the user is always moving the mouse.
 function Update () {
     Debug.Log("CupMovementWithMouseClick Update");
     //Get how far the mouse has moved by using the Input.GetAxis().
     var rotationX:float = Input.GetAxis("Mouse X") * sensitivityX;
     var rotationY:float = Input.GetAxis("Mouse Y") * sensitivityY;
 
     //Rotate the object around the camera's "up" axis, and the camera's "right" axis.
     // Rotate when left mouse button hold.
     if(Input.GetButton ("Fire1")){
         Debug.Log("CupMovementWithMouseClick Fire1");                
         
         // Also only rotate when mouse actually touches the object.                        
         if ( Input.GetMouseButtonDown(0)){
             Debug.Log("CLICKED");
             var hit:RaycastHit;
             var ray:Ray = Camera.main.ScreenPointToRay(Input.mousePosition);
             if(Physics.Raycast(ray, hit, 100.0)) {
                 Debug.Log("HIT!!");
                 
                 transform.RotateAroundLocal( referenceCamera.up        , -Mathf.Deg2Rad * rotationX );
                 transform.RotateAroundLocal( referenceCamera.right    ,  Mathf.Deg2Rad * rotationY );    
             }
         }
                                                                                 
     }
 
 }