Invalid left-hand side in assignment page error problem solution

Error screenshot:
screenshot content translation: the parameter quoted on the left is an error.
Screenshot of error code:

Reason for error:
user="zhousujuan"&&pass="12345678"The wording is incorrect. It should be written user=="zhousujuan"&&pass=="12345678".
No error is reported after the change. The program runs normally.

Code after change:

<script>
   //先弹窗，并获取用户初始输入的账号名和密码
   var user=prompt("请输入用户名：");
   var pass=prompt("请输入密码：");
   //放在while中判断，如果判断失败，则继续弹窗，弹窗完成继续判断，直到密码输入正确为止
   while(!(user=="zhousujuan"&&pass=="12345678")){
     
     
       var user=prompt("请输入用户名：");
    var pass=prompt("请输入密码：");
   }
   alert("成功");
 </script>

Screenshot of successful operation after the change: