我不确定我在这里缺少什么，我知道我可以添加 CSS 以从父 div 中删除填充，但我认为引导程序会使导航栏成为页面的全宽？这是我的代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<title>Contact</title>
<!--Bootstrap CSS-->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css" integrity="sha384-MCw98/SFnGE8fJT3GXwEOngsV7Zt27NXFoaoApmYm81iuXoPkFOJwJ8ERdknLPMO" crossorigin="anonymous">
<link rel="stylesheet" type="text/css" media="screen" href="main.css" />
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
</head>
<body>
<div class="container-fluid" id="outer">
<header>
<nav class="navbar navbar-expand-lg navbar-light bg-secondary">
<a class="navbar-brand" href="#">
<img src="\movieTheater.jpg" width="10%" height="10%" alt="">
Movie Theater
</a>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav ml-auto">
<li class="nav-item active">
<a class="nav-link" href="home.html">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="about.html">About</a>
</li>
<li class="nav-item">
<a class="nav-link" href="contact.html">Contact</a>
</li> …