css - 我希望 Bootstrap 导航在所有屏幕尺寸上始终处于折叠模式，因为它在移动设备上呈现

Question

<nav class="navbar navbar-inverse navbar-fixed-top">
      <div class="container">
        <div class="navbar-header">
          <button aria-controls="navbar" aria-expanded="false" data-target="#navbar" data-toggle="collapse" class="navbar-toggle collapsed" type="button">
            <span class="sr-only">Toggle navigation</span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
            <span class="icon-bar"></span>
          </button>
          <a href="#" class="navbar-brand">LOGO</a>
        </div>
        <div class="navbar-collapse collapse" id="navbar">
          <ul class="nav navbar-nav">
            <li class="active"><a href="#">Home</a></li>
            <li><a href="#about">About</a></li>
            <li><a href="#contact">Contact</a></li>
            <li class="dropdown">
              <a aria-expanded="false" aria-haspopup="true" role="button" data-toggle="dropdown" class="dropdown-toggle" href="#">Dropdown <span class="caret"></span></a>
              <ul class="dropdown-menu">
                <li><a href="#">Action</a></li>
                <li><a href="#">Another action</a></li>
                <li><a href="#">Something else here</a></li>
                <li class="divider" role="separator"></li>
                <li class="dropdown-header">Nav header</li>
                <li><a href="#">Separated link</a></li>
                <li><a href="#">One more separated link</a></li>
              </ul>
            </li>
          </ul>
        </div><!--/.nav-collapse -->
      </div>
    </nav>

Answer 1

这是移动导航的 CSS 规则的工作示例，您需要将其重置为不同的媒体查询，以便它们适用于所有视口(viewport)。

body,
html {
  padding-top: 30px;
}
@media (max-width: 2500px) {
  .custom-navbar .navbar-header {
    float: none;
  }
  .custom-navbar .navbar-left,
  .custom-navbar .navbar-right {
    float: none !important;
  }
  .custom-navbar .navbar-toggle {
    display: block;
  }
  .custom-navbar .navbar-collapse {
    border-top: 1px solid transparent;
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.1);
  }
  .custom-navbar.navbar-fixed-top {
    top: 0;
    border-width: 0 0 1px;
  }
  .custom-navbar .navbar-collapse.collapse {
    display: none!important;
  }
  .custom-navbar .navbar-nav {
    float: none!important;
    margin-top: 7.5px;
  }
  .custom-navbar .navbar-nav>li {
    float: none;
  }
  .custom-navbar .navbar-nav>li>a {
    padding-top: 10px;
    padding-bottom: 10px;
  }
  .custom-navbar .collapse.in {
    display: block !important;
  }
  .custom-navbar .navbar-nav .dropdown-menu > li > a,
  .custom-navbar .navbar-nav .dropdown-menu > li > a:hover,
  .custom-navbar .navbar-nav .dropdown-menu > li > a:focus {
    color: #777;
  }
  .custom-navbar .navbar-nav .open .dropdown-menu {
    position: static;
    float: none;
    width: auto;
    margin-top: 0;
    background-color: transparent;
    border: 0;
    -webkit-box-shadow: none;
    box-shadow: none;
  }
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>
<link href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css" rel="stylesheet" />
<nav class="navbar navbar-inverse custom-navbar navbar-fixed-top">
  <div class="container">
    <div class="navbar-header">
      <button aria-controls="navbar" aria-expanded="false" data-target="#navbar" data-toggle="collapse" class="navbar-toggle collapsed" type="button"> <span class="sr-only">Toggle navigation</span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>
        <span class="icon-bar"></span>

      </button> <a href="#" class="navbar-brand">LOGO</a>

    </div>
    <div class="navbar-collapse collapse" id="navbar">
      <ul class="nav navbar-nav">
        <li class="active"><a href="#">Home</a>

        </li>
        <li><a href="#about">About</a>

        </li>
        <li><a href="#contact">Contact</a>

        </li>
        <li class="dropdown"> <a aria-expanded="false" aria-haspopup="true" role="button" data-toggle="dropdown" class="dropdown-toggle" href="#">Dropdown <span class="caret"></span></a>

          <ul class="dropdown-menu">
            <li><a href="#">Action</a>

            </li>
            <li><a href="#">Another action</a>

            </li>
            <li><a href="#">Something else here</a>

            </li>
            <li class="divider" role="separator"></li>
            <li class="dropdown-header" role="separator">Nav header</li>
            <li><a href="#">One more separated link</a>

            </li>
          </ul>
        </li>
      </ul>
    </div>
    <!--/.nav-collapse -->
  </div>
</nav>
<div class="container">
  <div class="well well-lg">Boostrap Mobile</div>
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    the 1960s with the release of Letraset sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.Lorem Ipsum is simply dummy text of the printing and typesetting
    industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. It has survived not only five centuries, but also the leap into electronic
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    publishing software like Aldus PageMaker including versions of Lorem Ipsum.Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer
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    sheets containing Lorem Ipsum passages, and more recently with desktop publishing software like Aldus PageMaker including versions of Lorem Ipsum.Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's
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</div>