CSS로 반응형 사이드 탐색 메뉴를 만드는 방법은 무엇입니까?

다음은 CSS로 반응형 사이드 탐색 메뉴를 만드는 코드입니다 −

예시

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<style>
body {
   margin: 0;
   font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}
nav {
   margin: 0;
   padding: 0;
   width: 150px;
   background-color: #2f77e4;
   position: fixed;
   height: 100%;
   overflow: auto;
}
nav a {
   display: block;
   color: rgb(255, 255, 255);
   font-weight: bolder;
   font-size: 20px;
   padding: 16px;
   text-decoration: none;
}
nav a.selected {
   background-color: rgb(15, 189, 20);
   color: rgb(255, 255, 255);
}
nav a:hover:not(.selected) {
   background-color: white;
   color: #2f77e4;
}
div.content {
   margin-left: 200px;
   padding: 1px 16px;
   height: 1000px;
}
@media screen and (max-width: 700px) {
nav {
   width: 100%;
   height: auto;
   position: relative;
}
nav a {float: left;}
div.content {margin-left: 0;}
}
</style>
</head>
<body>
<nav class="sideBar">
<a class="selected" href="#">Home</a>
<a href="#">Login</a>
<a href="#">Register</a>
<a href="#">Message Us</a>
<a href="#">Contact Us</a>
</nav>
<div class="content">
<h1>Sample Text</h1>
<h2>Resize the browser to 700px to change vertical navbar to horizontal navbar</h2>
</div>
</body>
</html>