Bootstrap标头/ jumbotron背景图像

Question

我第一次搞乱Bootstrap并且正在努力将图像作为包含导航和jumbotron的标题的背景。目前我设置的图像没有出现，我不知道为什么。如果你可以指出我在哪里或什么需要改变的正确方向，将不胜感激。

<div class="container header-bg">
    <nav class="navbar" role="navigation">
        <div class="container">
            <div class="navbar-header">
              <button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#navbar" aria-expanded="false" aria-controls="navbar">
                <span class="sr-only">Toggle navigation</span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
                <span class="icon-bar"></span>
              </button>
              <a class="navbar-brand" href="#">Elliott Davidson</a>
            </div>
            <div id="navbar" class="collapse navbar-collapse">
              <ul class="nav navbar-nav pull-right">
                <li><a href="#about">About</a></li>
                <li><a href="#about">Pictures</a></li>
                <li><a href="#about">Videos</a></li>
                <li><a href="#about">Sponsors</a></li>
                <li><a href="#about">Blog</a></li>
                <li><a href="#contact">Contact</a></li>
              </ul>
            </div><!--/.nav-collapse -->
        </div>
    </nav>
    <div class="jumbotron">
      <div class="container">
        <h1>Elliott Davidson</h1>
        <p>This is a template for a simple marketing or informational website. It includes a large callout called a jumbotron and three supporting pieces of content. Use it as a starting point to create something more unique.</p>
        <p><a class="btn btn-primary btn-lg" href="#" role="button">Learn more</a></p>
      </div>
    </div>
</div>

    .header-bg {
      width:100%;
      height:475px;
      background: url("img/elliott-davidson-slider.jpg");
      background-size:cover;
    }

    .jumbotron {
      color: white;
      text-shadow: black 0.3em 0.3em 0.3em;
      background: transparent;
    }

Answer 1

background: url("../img/elliott-davidson-slider.jpg");

By - Yerko Palma

Answer 2

尝试添加“background-image”，如下所示：

.header-bg {
  width:100%;
  height:475px;
  background-image: url("img/elliott-davidson-slider.jpg");
  background-size:cover;
}