如何使Bootstrap导航栏居中并具有特定的宽度，而不是响应式宽度或静态宽度？

<link rel="stylesheet" href="https://cdn.staticfile.org/twitter-bootstrap/4.6.0/css/bootstrap.min.css">
<script src="https://cdn.staticfile.org/jquery/3.5.1/jquery.min.js"></script>
<script src="https://cdn.staticfile.org/twitter-bootstrap/4.6.0/js/bootstrap.min.js"></script>

<div class="container text-center">
  <nav class="navbar navbar-expand-lg navbar-light bg-light">
    <!-- 导航栏内容 -->
  </nav>
</div>

<nav class="navbar navbar-expand-lg navbar-light bg-light" style="width: 800px;">
  <!-- 导航栏内容 -->
</nav>

<style>
.custom-navbar {
  width: 800px;
}
</style>
<nav class="navbar navbar-expand-lg navbar-light bg-light custom-navbar">
  <!-- 导航栏内容 -->
</nav>

<nav class="navbar navbar-expand-lg navbar-light bg-light custom-navbar">
  <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarNav" aria-controls="navbarNav" aria-expanded="false" aria-label="Toggle navigation">
    <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" id="navbarNav">
    <ul class="navbar-nav ml-auto">
      <li class="nav-item active">
        <a class="nav-link" href="#">Home</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">About</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Services</a>
      </li>
      <li class="nav-item">
        <a class="nav-link" href="#">Contact</a>
      </li>
    </ul>
  </div>
</nav>