Problem with movement/camera script. [Need some support]

Hello there, I've started using unity like 15 hours ago and I really like learning new stuff and I always wanted to learn how to make games and stuff like writing codes/scripts. So I have this problem with movement and camera setting and I would really appriciate your help. The problem is I wanted to make it when I turn right or left that my body will also turn, but right now when I look up or down my body is also turning and I did not wanted it. Check this link for video with issue https://streamable.com/zss9mg

Here's my code, hopefully you can help me.

Kind regards, Oscar

using System.Collections; using System.Collections.Generic; using UnityEngine;

public class playerMovement : MonoBehaviour { public float speed = 25.0F; public float jumpSpeed = 8.0F; public float gravity = 20.0F; private Vector3 moveDirection = Vector3.zero; private float turner; private float looker; public float sensitivity = 5;

  // Use this for initialization
  void Start () {
      
  }
  
  // Update is called once per frame
  void Update () {
      CharacterController controller = GetComponent<CharacterController>();
      // is the controller on the ground?
      if (controller.isGrounded) {
          //Feed moveDirection with input.
          moveDirection = new Vector3(Input.GetAxis("Horizontal"), 0, Input.GetAxis("Vertical"));
          moveDirection = transform.TransformDirection(moveDirection);
          //Multiply it by speed.
          moveDirection *= speed;
          //Jumping
          if (Input.GetButton("Jump"))
              moveDirection.y = jumpSpeed;
          
      }
      turner = Input.GetAxis ("Mouse X")* sensitivity;
      looker = -Input.GetAxis ("Mouse Y")* sensitivity;
      if(turner != 0){
          //Code for action on mouse moving right
          transform.eulerAngles += new Vector3 (0,turner,0);
      }
      if(looker != 0){
          //Code for action on mouse moving right
          transform.eulerAngles += new Vector3 (looker,0,0);
      }
      //Applying gravity to the controller
      moveDirection.y -= gravity * Time.deltaTime;
      //Making the character move
      controller.Move(moveDirection * Time.deltaTime);
  }

}