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導航欄

Bootstrap 強大的響應式導航標題導航欄的文檔和示例。包括對品牌、導航等的支持,包括對我們的折疊插件的支持。

這個怎麼運作

在開始使用導航欄之前,您需要了解以下內容:

  • 導航欄需要一個用於響應式折疊和.navbar配色方案類的包裝。.navbar-expand{-sm|-md|-lg|-xl|-xxl}
  • 默認情況下,導航欄及其內容是流動的。更改容器以不同方式限制其水平寬度。
  • 使用我們的間距flex實用程序類來控制導航欄中的間距和對齊方式。
  • 導航欄默認情況下是響應式的,但您可以輕鬆修改它們以更改它。響應行為取決於我們的 Collapse JavaScript 插件。
  • 通過使用<nav>元素來確保可訪問性,或者,如果使用更通用的元素,例如 a <div>,則在每個導航欄中添加 arole="navigation"以明確將其標識為輔助技術用戶的標誌性區域。
  • 通過aria-current="page"用於當前頁面或aria-current="true"集合中的當前項目來指示當前項目。
該組件的動畫效果依賴於 prefers-reduced-motion媒體查詢。請參閱 我們可訪問性文檔的減少運動部分

支持的內容

導航欄內置了對少數子組件的支持。根據需要從以下選項中進行選擇:

  • .navbar-brand為您的公司、產品或項目名稱。
  • .navbar-nav用於全高度和輕量級導航(包括對下拉菜單的支持)。
  • .navbar-toggler用於我們的折疊插件和其他導航切換行為。
  • 適用於任何表單控件和操作的 Flex 和間距實用程序。
  • .navbar-text用於添加垂直居中的文本字符串。
  • .collapse.navbar-collapse用於按父斷點分組和隱藏導航欄內容。
  • 添加一個可選項.navbar-scroll來設置max-height滾動擴展的導航欄內容

這是一個包含在響應式輕主題導航欄中的所有子組件的示例,該導航欄會在lg(大)斷點處自動折疊。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarSupportedContent">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
            Dropdown
          </a>
          <ul class="dropdown-menu" aria-labelledby="navbarDropdown">
            <li><a class="dropdown-item" href="#">Action</a></li>
            <li><a class="dropdown-item" href="#">Another action</a></li>
            <li><hr class="dropdown-divider"></li>
            <li><a class="dropdown-item" href="#">Something else here</a></li>
          </ul>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

此示例使用背景( bg-light) 和間距( my-2, my-lg-0, me-sm-0, my-sm-0) 實用程序類。

.navbar-brand可以應用於大多數元素,但錨點效果最好,因為某些元素可能需要實用程序類或自定義樣式。

文本

在類的元素中添加您的文本.navbar-brand

<!-- As a link -->
<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
  </div>
</nav>

<!-- As a heading -->
<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <span class="navbar-brand mb-0 h1">Navbar</span>
  </div>
</nav>

圖片

您可以將 中的文本替換.navbar-brand<img>.

<nav class="navbar navbar-light bg-light">
  <div class="container">
    <a class="navbar-brand" href="#">
      <img src="/docs/5.0/assets/brand/bootstrap-logo.svg" alt="" width="30" height="24">
    </a>
  </div>
</nav>

圖片和文字

您還可以使用一些其他實用程序同時添加圖像和文本。注意.d-inline-block.align-text-top的添加<img>

<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">
      <img src="/docs/5.0/assets/brand/bootstrap-logo.svg" alt="" width="30" height="24" class="d-inline-block align-text-top">
      Bootstrap
    </a>
  </div>
</nav>

導航欄導航鏈接建立在我們的.nav選項之上,帶有自己的修飾符類,並且需要使用切換器來實現正確的響應式樣式。導航欄中的導航也將佔用盡可能多的水平空間,以保持導航欄內容安全對齊。

添加.active類 on.nav-link以指示當前頁面。

請注意,您還應該aria-current在 active 上添加屬性.nav-link

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-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">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Features</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Pricing</a>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
        </li>
      </ul>
    </div>
  </div>
</nav>

而且因為我們為導航使用類,如果您願意,您可以完全避免使用基於列表的方法。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNavAltMarkup" aria-controls="navbarNavAltMarkup" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarNavAltMarkup">
      <div class="navbar-nav">
        <a class="nav-link active" aria-current="page" href="#">Home</a>
        <a class="nav-link" href="#">Features</a>
        <a class="nav-link" href="#">Pricing</a>
        <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
      </div>
    </div>
  </div>
</nav>

您還可以在導航欄中使用下拉菜單。下拉菜單需要一個包裝元素來定位,因此請務必使用單獨和嵌套的元素,.nav-item如下.nav-link所示。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarNavDropdown" aria-controls="navbarNavDropdown" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarNavDropdown">
      <ul class="navbar-nav">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Features</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Pricing</a>
        </li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" id="navbarDropdownMenuLink" role="button" data-bs-toggle="dropdown" aria-expanded="false">
            Dropdown link
          </a>
          <ul class="dropdown-menu" aria-labelledby="navbarDropdownMenuLink">
            <li><a class="dropdown-item" href="#">Action</a></li>
            <li><a class="dropdown-item" href="#">Another action</a></li>
            <li><a class="dropdown-item" href="#">Something else here</a></li>
          </ul>
        </li>
      </ul>
    </div>
  </div>
</nav>

形式

在導航欄中放置各種表單控件和組件:

<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <form class="d-flex">
      <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
      <button class="btn btn-outline-success" type="submit">Search</button>
    </form>
  </div>
</nav>

.navbar使用 flex 佈局的直接子元素,默認為justify-content: space-between. 根據需要使用其他flex 實用程序來調整此行為。

<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand">Navbar</a>
    <form class="d-flex">
      <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
      <button class="btn btn-outline-success" type="submit">Search</button>
    </form>
  </div>
</nav>

輸入組也可以工作。如果您的導航欄是一個完整的表單,或者大部分是一個表單,您可以使用該<form>元素作為容器並保存一些 HTML。

<nav class="navbar navbar-light bg-light">
  <form class="container-fluid">
    <div class="input-group">
      <span class="input-group-text" id="basic-addon1">@</span>
      <input type="text" class="form-control" placeholder="Username" aria-label="Username" aria-describedby="basic-addon1">
    </div>
  </form>
</nav>

這些導航欄表單也支持各種按鈕。這也是一個很好的提醒,垂直對齊實用程序可用於對齊不同大小的元素。

<nav class="navbar navbar-light bg-light">
  <form class="container-fluid justify-content-start">
    <button class="btn btn-outline-success me-2" type="button">Main button</button>
    <button class="btn btn-sm btn-outline-secondary" type="button">Smaller button</button>
  </form>
</nav>

文本

導航欄可能會在.navbar-text. 此類調整文本字符串的垂直對齊和水平間距。

<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <span class="navbar-text">
      Navbar text with an inline element
    </span>
  </div>
</nav>

根據需要與其他組件和實用程序混合搭配。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar w/ text</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarText" aria-controls="navbarText" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarText">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Features</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Pricing</a>
        </li>
      </ul>
      <span class="navbar-text">
        Navbar text with an inline element
      </span>
    </div>
  </div>
</nav>

配色方案

background-color由於主題類和實用程序的結合,對導航欄進行主題化從未如此簡單。選擇.navbar-light用於淺色背景色或.navbar-dark深色背景色。然後,使用.bg-*實用程序進行自定義。

<nav class="navbar navbar-dark bg-dark">
  <!-- Navbar content -->
</nav>

<nav class="navbar navbar-dark bg-primary">
  <!-- Navbar content -->
</nav>

<nav class="navbar navbar-light" style="background-color: #e3f2fd;">
  <!-- Navbar content -->
</nav>

容器

儘管它不是必需的,但您可以將導航欄包裹在 a.container中以使其在頁面上居中 - 儘管請注意仍然需要內部容器。或者,您可以在 內添加一個容器,以僅將固定或靜態頂部導航欄.navbar的內容居中。

<div class="container">
  <nav class="navbar navbar-expand-lg navbar-light bg-light">
    <div class="container-fluid">
      <a class="navbar-brand" href="#">Navbar</a>
    </div>
  </nav>
</div>

使用任何響應式容器來更改導航欄中內容的顯示寬度。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-md">
    <a class="navbar-brand" href="#">Navbar</a>
  </div>
</nav>

放置

使用我們的位置實用程序將導航欄放置在非靜態位置。選擇固定到頂部、固定到底部或粘到頂部(隨頁面滾動,直到它到達頂部,然後停留在那裡)。固定導航欄使用position: fixed,這意味著它們是從 DOM 的正常流程中拉出的,並且可能需要自定義 CSS(例如,padding-top在 上<body>)以防止與其他元素重疊。

另請注意,並不是每個瀏覽器都完全支持.sticky-top使用position: sticky

<nav class="navbar navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Default</a>
  </div>
</nav>
<nav class="navbar fixed-top navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Fixed top</a>
  </div>
</nav>
<nav class="navbar fixed-bottom navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Fixed bottom</a>
  </div>
</nav>
<nav class="navbar sticky-top navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Sticky top</a>
  </div>
</nav>

滾動

添加.navbar-nav-scroll.navbar-nav(或其他導航欄子組件)以在折疊導航欄的可切換內容中啟用垂直滾動。默認情況下,滾動開始於75vh(或視口高度的 75%),但您可以使用本地 CSS 自定義屬性--bs-navbar-height或自定義樣式覆蓋它。當導航欄展開時,在較大的視口中,內容將像在默認導航欄中一樣顯示。

請注意,這種行為有一個潛在的缺點,即overflow設置overflow-y: auto時(需要在此處滾動內容),overflow-x相當於auto,它將裁剪一些水平內容。

.navbar-nav-scroll這是一個使用with的示例導航欄style="--bs-scroll-height: 100px;",帶有一些額外的邊距實用程序以獲得最佳間距。

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar scroll</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarScroll" aria-controls="navbarScroll" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarScroll">
      <ul class="navbar-nav me-auto my-2 my-lg-0 navbar-nav-scroll" style="--bs-scroll-height: 100px;">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" id="navbarScrollingDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false">
            Link
          </a>
          <ul class="dropdown-menu" aria-labelledby="navbarScrollingDropdown">
            <li><a class="dropdown-item" href="#">Action</a></li>
            <li><a class="dropdown-item" href="#">Another action</a></li>
            <li><hr class="dropdown-divider"></li>
            <li><a class="dropdown-item" href="#">Something else here</a></li>
          </ul>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Link</a>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

響應行為

導航欄可以使用.navbar-toggler.navbar-collapse.navbar-expand{-sm|-md|-lg|-xl|-xxl}類來確定其內容何時折疊在按鈕後面。結合其他實用程序,您可以輕鬆選擇何時顯示或隱藏特定元素。

對於從不折疊.navbar-expand的導航欄,在導航欄上添加類。對於總是折疊的導航欄,不要添加任何.navbar-expand類。

切換器

導航欄切換器默認是左對齊的,但如果它們跟隨像 a 這樣的兄弟元素.navbar-brand,它們將自動對齊到最右邊。反轉標記將反轉切換器的位置。以下是不同切換樣式的示例。

.navbar-brand在最小斷點處沒有顯示:

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarTogglerDemo01" aria-controls="navbarTogglerDemo01" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarTogglerDemo01">
      <a class="navbar-brand" href="#">Hidden brand</a>
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

左側顯示品牌名稱,右側顯示切換器:

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarTogglerDemo02" aria-controls="navbarTogglerDemo02" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="navbarTogglerDemo02">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

左側是切換器,右側是品牌名稱:

<nav class="navbar navbar-expand-lg navbar-light bg-light">
  <div class="container-fluid">
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarTogglerDemo03" aria-controls="navbarTogglerDemo03" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <a class="navbar-brand" href="#">Navbar</a>
    <div class="collapse navbar-collapse" id="navbarTogglerDemo03">
      <ul class="navbar-nav me-auto mb-2 mb-lg-0">
        <li class="nav-item">
          <a class="nav-link active" aria-current="page" href="#">Home</a>
        </li>
        <li class="nav-item">
          <a class="nav-link" href="#">Link</a>
        </li>
        <li class="nav-item">
          <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control me-2" type="search" placeholder="Search" aria-label="Search">
        <button class="btn btn-outline-success" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

外部內容

有時您想使用折疊插件來觸發結構上位於.navbar. 因為我們的插件適用於iddata-bs-target匹配,所以很容易做到!

<div class="collapse" id="navbarToggleExternalContent">
  <div class="bg-dark p-4">
    <h5 class="text-white h4">Collapsed content</h5>
    <span class="text-muted">Toggleable via the navbar brand.</span>
  </div>
</div>
<nav class="navbar navbar-dark bg-dark">
  <div class="container-fluid">
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navbarToggleExternalContent" aria-controls="navbarToggleExternalContent" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
  </div>
</nav>

執行此操作時,我們建議您添加額外的 JavaScript,以便在容器打開時以編程方式將焦點移至容器。否則,鍵盤用戶和輔助技術用戶可能很難找到新顯示的內容 - 特別是如果打開的容器位於文檔結構中的切換器之前。我們還建議確保切換器具有aria-controls指向id內容容器的屬性。從理論上講,這允許輔助技術用戶直接從切換器跳轉到它控制的容器——但目前對此的支持相當不完整。

薩斯

變量

$navbar-padding-y:                  $spacer * .5;
$navbar-padding-x:                  null;

$navbar-nav-link-padding-x:         .5rem;

$navbar-brand-font-size:            $font-size-lg;
// Compute the navbar-brand padding-y so the navbar-brand will have the same height as navbar-text and nav-link
$nav-link-height:                   $font-size-base * $line-height-base + $nav-link-padding-y * 2;
$navbar-brand-height:               $navbar-brand-font-size * $line-height-base;
$navbar-brand-padding-y:            ($nav-link-height - $navbar-brand-height) * .5;
$navbar-brand-margin-end:           1rem;

$navbar-toggler-padding-y:          .25rem;
$navbar-toggler-padding-x:          .75rem;
$navbar-toggler-font-size:          $font-size-lg;
$navbar-toggler-border-radius:      $btn-border-radius;
$navbar-toggler-focus-width:        $btn-focus-width;
$navbar-toggler-transition:         box-shadow .15s ease-in-out;
$navbar-dark-color:                 rgba($white, .55);
$navbar-dark-hover-color:           rgba($white, .75);
$navbar-dark-active-color:          $white;
$navbar-dark-disabled-color:        rgba($white, .25);
$navbar-dark-toggler-icon-bg:       url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'><path stroke='#{$navbar-dark-color}' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/></svg>");
$navbar-dark-toggler-border-color:  rgba($white, .1);

$navbar-light-color:                rgba($black, .55);
$navbar-light-hover-color:          rgba($black, .7);
$navbar-light-active-color:         rgba($black, .9);
$navbar-light-disabled-color:       rgba($black, .3);
$navbar-light-toggler-icon-bg:      url("data:image/svg+xml,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'><path stroke='#{$navbar-light-color}' stroke-linecap='round' stroke-miterlimit='10' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/></svg>");
$navbar-light-toggler-border-color: rgba($black, .1);

$navbar-light-brand-color:                $navbar-light-active-color;
$navbar-light-brand-hover-color:          $navbar-light-active-color;
$navbar-dark-brand-color:                 $navbar-dark-active-color;
$navbar-dark-brand-hover-color:           $navbar-dark-active-color;

環形

響應式導航欄展開/折疊類(例如.navbar-expand-lg)與$breakpoints地圖組合併通過scss/_navbar.scss.

// Generate series of `.navbar-expand-*` responsive classes for configuring
// where your navbar collapses.
.navbar-expand {
  @each $breakpoint in map-keys($grid-breakpoints) {
    $next: breakpoint-next($breakpoint, $grid-breakpoints);
    $infix: breakpoint-infix($next, $grid-breakpoints);

    // stylelint-disable-next-line scss/selector-no-union-class-name
    &#{$infix} {
      @include media-breakpoint-up($next) {
        flex-wrap: nowrap;
        justify-content: flex-start;

        .navbar-nav {
          flex-direction: row;

          .dropdown-menu {
            position: absolute;
          }

          .nav-link {
            padding-right: $navbar-nav-link-padding-x;
            padding-left: $navbar-nav-link-padding-x;
          }
        }

        .navbar-nav-scroll {
          overflow: visible;
        }

        .navbar-collapse {
          display: flex !important; // stylelint-disable-line declaration-no-important
          flex-basis: auto;
        }

        .navbar-toggler {
          display: none;
        }
      }
    }
  }
}