Question

#header-img{
  background-image: url("https://helpx.adobe.com/ca/stock/how-to/visual-reverse-image-search/_jcr_content/main-pars/image.img.jpg/visual-reverse-image-search-v2_1000x560.jpg");
  height: 400px;
  background-size: contain;
  background-repeat: no-repeat;
  background-attachment: fixed;
  display: block;
}

当我添加固定在CSS中的背景附件时，会出现问题。该图像不仅位于导航栏后面，而且当我在顶部使用margin-top时，它会从顶部吞噬图像；当我更改浏览器宽度以检查响应性时，该图像会从顶部消失，并不断从顶部消失。 https://jsfiddle.net/j2z9eoy8/

<!doctype html>
    <html lang="en">
      <head>
        <!-- Required meta tags -->
        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">

        <!-- Bootstrap CSS -->
        <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">

        <title>Hello, world!</title>
      </head>
      <body>
         <header>
          <nav class="navbar navbar-expand-lg navbar-light bg-light">
      <a class="navbar-brand" href="#">Navbar</a>
      <button class="navbar-toggler" type="button" data-toggle="collapse" data-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 mr-auto">
          <li class="nav-item active">
            <a class="nav-link" href="#">Home <span class="sr-only">(current)</span></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-toggle="dropdown" aria-haspopup="true" aria-expanded="false">
              Dropdown
            </a>
            <div class="dropdown-menu" aria-labelledby="navbarDropdown">
              <a class="dropdown-item" href="#">Action</a>
              <a class="dropdown-item" href="#">Another action</a>
              <div class="dropdown-divider"></div>
              <a class="dropdown-item" href="#">Something else here</a>
            </div>
          </li>
          <li class="nav-item">
            <a class="nav-link disabled" href="#" tabindex="-1" aria-disabled="true">Disabled</a>
          </li>
        </ul>
        <form class="form-inline my-2 my-lg-0">
          <input class="form-control mr-sm-2" type="search" placeholder="Search" aria-label="Search">
          <button class="btn btn-outline-success my-2 my-sm-0" type="submit">Search</button>
        </form>
      </div>
    </nav>
    <div id="header-img">

    </div>
        </header>
       <div class="container-fluid">
         hi
       </div>

        <!-- Optional JavaScript -->
        <!-- jQuery first, then Popper.js, then Bootstrap JS -->
        <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
        <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
      </body>
    </html>

Answer 1

删除background-attachment:fixed; 并将background-size更改为cover

可以用height: calc(100vh - XXXX);设置容器的高度 XXXX是导航高度。

使用固定附件且页边距不起作用时，页眉图像在导航栏后面

1 个答案: