how to limit rotation of on object? (Quaternion.Slerp)

Hello, i have a script that make an object rotates toward the player but i want to limit the X rotation (clamping) and remove the Y rotation (0 at all times) how can i do that?

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 
 public class EnemyRotateTowardsPlayer : MonoBehaviour
 {
     GameObject player;
     Quaternion lookAtPlayer;
     void Start()
     {
         player = GameObject.Find("Player");
     }
     void Update()
     {
         lookAtPlayer = Quaternion.LookRotation((player.transform.position + new Vector3(0, 1.4f, 0)) -transform.position);     //rotation angle to look at player
         transform.rotation = Quaternion.Slerp(transform.rotation, lookAtPlayer, 20 * Time.deltaTime);
     }
 }