Simple Item Rotation Relative to Camera Script

ItemOverview.cs

using UnityEngine;

public class ItemOverview : MonoBehaviour
{
    [SerializeField] private Transform center;
    [SerializeField] private Transform viewCamera;
    [SerializeField] private Transform overviewItem;
    [SerializeField] private float itemRotationSpeed = 10f;
    [SerializeField] private float cameraRotationSpeed = 0.5f;

    [SerializeField] private float cameraScrollSpeed = 1f;

    [SerializeField] private float minCameraDistance = 2f;
    [SerializeField] private float maxCameraDistance = 5f;

    [Range(-90f, 0f)]
    [SerializeField] private float maxCameraVerticalAngle = -90f;
    [Range(0f, 90f)]
    [SerializeField] private float minCameraVerticalAngle = 90f;

    private Vector3 cameraRot;
    private float cameraDistance;

    private Quaternion startRot;
    private Vector2 deltaRot;

    private void Start()
    {
        cameraDistance = (minCameraDistance + maxCameraDistance) / 2f;
    }

    void Update()
    {
        cameraDistance = Mathf.Clamp(cameraDistance - Input.mouseScrollDelta.y * (cameraScrollSpeed * cameraDistance) / 2f, minCameraDistance, maxCameraDistance);

        if (Input.GetKeyDown(KeyCode.Mouse0))
        {
            startRot = overviewItem.rotation;
            deltaRot = Vector2.zero;
        }
        else if (Input.GetKey(KeyCode.Mouse0))
        {
            var delta = Input.mousePositionDelta;
            deltaRot += new Vector2(delta.x, delta.y);
            overviewItem.rotation =
                Quaternion.AngleAxis(-deltaRot.x * Mathf.Deg2Rad * itemRotationSpeed, viewCamera.up) *
                Quaternion.AngleAxis(deltaRot.y * Mathf.Deg2Rad * itemRotationSpeed, viewCamera.right) *
                startRot;
        }

        if (Input.GetKey(KeyCode.Mouse2) && !Input.GetKeyDown(KeyCode.Mouse2))
        {
            cameraRot += new Vector3(-Input.mousePositionDelta.y * cameraRotationSpeed, Input.mousePositionDelta.x * cameraRotationSpeed, 0);
            cameraRot = new Vector3(Mathf.Clamp(cameraRot.x, -90, 90), cameraRot.y, 0);

            viewCamera.rotation = Quaternion.Euler(cameraRot.x, cameraRot.y, 0);
        }
        viewCamera.position = viewCamera.rotation * Vector3.back * cameraDistance + center.position;
    }
}