Q1
如何将文本<h1>Welcome to Liam Docherty's Digital Portfolio</h1>置于导航栏文本的中心位置？
Q2
如何让<DIV>代表背景图片？
我不想因为各种原因而将第1部分设为背景图像，这就是为什么我要创建一个<DIV>它自己的背景图像。我尝试将HTML div class="hero"></div>与下面的CSS一起使用。然而，没有任何反应。
.hero {
background-image: url("https://static.pexels.com/photos/48727/pexels-photo-48727.jpeg");
background-attachment: fixed;
}
HTML
<body>
<nav class="navbar navbar-default navbar-fixed-top">
<div class="container-fluid">
<!-- Brand and toggle get grouped for better mobile display -->
<div class="navbar-header">
<button type="button" class="navbar-toggle collapsed" data-toggle="collapse" data-target="#bs-example-navbar-collapse-1" aria-expanded="false">
<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="#"><img src="http://placehold.it/60x60" alt="Your Brand Name"></a>
<h1 class="nav-title">Welcome to Liam Docherty's Digital Portfolio</h1>
</div>
<!-- Collect the nav links, forms, and other content for toggling -->
<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
<ul class="nav navbar-nav">
<li><a href="#">Home</a>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="true">About Me <span class="caret"></span></a>
<ul class="dropdown-menu">
<li><a href="#">Action</a>
</li>
<li><a href="#section3">Contact</a>
</li>
<li><a href="#">Something else here</a>
</li>
<li><a href="#">Separated link</a>
</li>
<li><a href="#">One more separated link</a>
</li>
</ul>
</li>
<li class="dropdown">
<a href="#" class="dropdown-toggle" data-toggle="dropdown" role="button" aria-haspopup="true" aria-expanded="false">Units <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><a href="#">Separated link</a>
</li>
<li><a href="#">One more separated link</a>
</li>
</ul>
</li>
<li><a href="#">Clients</a>
</li>
<li><a href="#contact-me">Contact Me</a>
</li>
</ul>
</div><!-- /.navbar-collapse -->
</div><!-- /.container-fluid -->
</nav>
<section id="section1" class="section1">
<div class="hero"></div>
<a href="#section2"><i class="fa fa-angle-down" style="font-size:100px;"></i></a>
</section>
<section id="section2" class="section2">
<a href="#contact-me"> <i class="fa fa-angle-down" style="font-size:100px;"></i></a>
</section>
<section id="contact-me" class="contact_section section3">
<a href="#section1"> <i class="fa fa-angle-up" style="font-size:100px;"></i></a>
</section>
<script src="https://code.jquery.com/jquery-3.1.1.js" integrity="sha256-16cdPddA6VdVInumRGo6IbivbERE8p7CQR3HzTBuELA=" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<footer>
<div class="page">
<h1 class="footer">Copyright © 2017 Liam Docherty's Site. All rights reserved.</h1>
</div>
</footer>
</body>
CSS
<style>
body {
margin: 0;
padding: 0;
}
.navbar.navbar-default {
background-color: #4D5061;
height: 10vh;
z-index: 100;
}
.navbar.navbar-default ul {
list-style-type: none;
text-align: right;
}
.navbar.navbar-default ul li {
display: inline-block;
}
.dropdown-menu li {
text-align:center
}
.dropdown .dropdown-menu {
background-color: #4D5061;
}
.dropdown .dropdown-menu a {
color: white;
}
.navbar.navbar-default ul li a {
display: inline-block;
padding: 3.5vh 8px 4px;
color: white;
text-decoration: none;
font-size: 14pt;
font-family: 'Roboto', sans-serif;
}
.navbar.navbar-default ul li:after {
content: '';
position: absolute;
right: 50%;
bottom: 0;
left: 50%;
height: 3px;
background-color: #FFFFFF;
border-radius: 9px;
transition: all .2s;
}
.navbar.navbar-default ul li a:hover {
color: white;
}
.nav.navbar-nav,
.nav.navbar-nav>li {
float: none;
}
.navbar.navbar-default ul li:hover:after {
right: 0;
left: 0;
}
.nav>li>a:hover {
background-color: rgba(17, 17, 17, 0.2);
}
#logo {
padding-top: 2vh;
padding-left: 20px;
float: left;
}
nav-title {
display: block;
margin: 0 auto; /*auto will do the centering trick*/
width: 80%; /*or any width*/
position: relative;
}
.hero {
background-image: url("https://static.pexels.com/photos/48727/pexels-photo-48727.jpeg");
background-attachment: fixed;
position:absolute;
width: 100%;
width: 100vw;
height: 100%;
height: 70vh;
}
section {
position: relative;
height: 95vh;
}
.section1 {
height: 100vh;
text-align: center;
color: white;
}
.section2 {
//height: 95vh;
background-color: #11B5E4;
text-align: center;
color: white;
}
.section3 {
//height: 95vh;
background-color: #EDF7F6;
text-align: center;
color: white;
}
.fa-angle-down {
color: #4D5061;
position: absolute;
bottom: 0px;
}
.fa-angle-up {
color: #4D5061;
position: absolute;
bottom: 0px;
}
.footer {
height: 5vh;
background-color: #4D5061;
text-align: center;
padding:0;
right:0;
bottom:0;
left:0:
}
h1{
font-size: 14pt;
margin:0;
text-align: center;
color: white;
font-family: 'Roboto', sans-serif;
}
.navbar.navbar-default ul.dropdown-menu li,
.navbar.navbar-default ul.dropdown-menu li a {
position: relative;
display: block;
}
</style>
答案 0 :(得分：0)
首先考虑你的第二个问题 - 你拥有的英雄元素没有任何高度 - 这就是图像不显示的原因。如果您希望图像在整个高度上显示为背景，则可以将这些元素添加到.hero样式中：
position:absolute;
height:100%;
width:100%;
当我将代码复制并粘贴到普通文件中时，导航不会显示扩展，因此很难回答问题1. H1中的文本已经针对页面本身居中。如果您可以提供URL或代码集，则更容易回答这一点。
答案 1 :(得分：0)
Q2： 没有任何反应的原因是因为默认情况下任何DIV高度和宽度都是0px，所以你必须明确提到高度和宽度。 如果你想要英雄形象是100％的高度和宽度的100％，我建议你在CSS中使用vw（视口宽度）和vh（视口高度值），其中100vw表示100％的视口宽度（高度相同的逻辑）。 像这里：
.hero {
background-image: url("https://static.pexels.com/photos/48727/pexels-photo-48727.jpeg");
background-attachment: fixed;
position: fixed;
width: 100%;
width: 100vw;
height: 100%;
height: 100vh;
}
百分比值是为了向后兼容。
Q1： 将h1置于div中并将其置于中心位置：
<div>
<h1>Welcome to Liam Docherty's Digital Portfolio</h1>
</div>
CSS：
div{
display: block;
margin: 0 auto; /*auto will do the centering trick*/
width: 80%; /*or any width*/
position: relative;
}
div必须在导航容器之外。