Weird Rotation Reset

I'm creating a game that requires the player to tilt a table to navigate a ball through a maze. I've gotten the table to rotate around the Z and X axes as I need them to, however whenever I switch which axis the table is rotating around the table resets and rotates from the flat position. Then if I switch axes again the table resets to its most recent rotation around the current axis. Example: Z-rotation --> attempt X-rotation --> table resets --> X-rotation. I apologize if this doesn't make any sense.

 public float rotationSpeed = 1;
     public float resetSpeed = 10;
 
     private Quaternion level;
 
     private float minX = -30;
     private float maxX = 30;
     private float minZ = -30;
     private float maxZ = 30;
     
 
     private float rotX;
     private float rotZ;
 
     // Use this for initialization
     void Start() {
         level = transform.rotation;
     }
 
     // Update is called once per frame
     void Update()
     {
         rotX += Input.GetAxis("RotateX") * rotationSpeed;
         rotX = Mathf.Clamp(rotX, minX, maxX);
 
         rotZ += Input.GetAxis("RotateZ") * rotationSpeed;
         rotZ = Mathf.Clamp(rotZ, minZ, maxZ);
 
         if(Input.GetKey(KeyCode.LeftArrow) || Input.GetKey(KeyCode.RightArrow)) 
         {
             transform.rotation = Quaternion.AngleAxis(rotX, Vector3.right);
             rotX = Mathf.Clamp(rotX, minX, maxX);
         }
         
         if(Input.GetKey(KeyCode.UpArrow) || Input.GetKey(KeyCode.DownArrow))
         {
             transform.rotation = Quaternion.AngleAxis(rotZ, Vector3.forward);
             rotZ = Mathf.Clamp(rotZ, minZ, maxZ);
         }