屏幕崩溃后，导航栏切换器隐藏在图像后面

Question

切换按钮的设计仅适用于xs屏幕，所有导航链接都指向切换按钮。但是，一旦我点击切换按钮，它就会出现一次白色背景，然后突然塌陷到导航栏的大小，使导航链接与导航栏下方的内容合并。您可以通过查看图像来更好地理解它。请帮忙！

<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">

<nav class="navbar navbar-light navbar-expand-sm fixed-top">
    <div class="container">
        <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#Navbar">
            <i class="navbar-toggler-icon"></i>
        </button>
        <a class="mr-auto navbar-brand nh myfont" href=".\index.html"> <img src="images/logo.png" width=6 0px height=7 0px> Sidhant Aggarwal</a>

        <div class="collapse navbar-collapse" id="Navbar">
            <ul class="navbar-nav mr-auto nl">
                <li class="nav-item mrn"> <a class="nav-link" href="#about"> About</a></li>
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Answer 1

您是否为导航栏导航指定了背景？您可以指定一种颜色来确定它

下面的工作片段：

.restOfThePage {
  margin-top: 100px;
}

.navbar-nav {
  background-color: #fff;
}

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.16.0/umd/popper.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js"></script>

<nav class="navbar navbar-light navbar-expand-sm fixed-top">
  <div class="container">
    <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#Navbar">
                <i class="navbar-toggler-icon"></i>
            </button>
    <a class="mr-auto navbar-brand nh myfont" href=".\index.html"> <img src="images/logo.png" width=6 0px height=7 0px> Sidhant Aggarwal</a>
    <div class="collapse navbar-collapse" id="Navbar">
      <ul class="navbar-nav mr-auto nl">
        <li class="nav-item mrn"> <a class="nav-link" href="#about"> About</a></li>
        <li class="nav-item mrn"> <a class="nav-link" href="#"> Resume</a></li>
        <li class="nav-item mrn"> <a class="nav-link" href=".\contactus.html"> Certifications</a></li>
      </ul>
    </div>
    <ul class="navbar-nav ml-auto nav-flex-icons flex-row">
      <li class="nav-item"> <a class="btn btn-social-icon" href="http://www.linkedin.com/in/"><i class = "fa fa-linkedin fa-xs"></i></a></li>
      <li class="nav-item"><a class="btn btn-social-icon" href="mailto:"><i class = "fa fa-github fa-xs"></i></a></li>
      <li class="nav-item"><a class="btn btn-social-icon" href="mailto:"><i class = "fa fa-envelope fa-xs"></i></a></li>
    </ul>
  </div>
</nav>
<div class='restOfThePage'>
  <h1>Other content</h1>
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</div>