<header>
 <a href="#0" class="cd-logo"><img src="img/cd-logo.svg"></a>
  
 <button class="cd-nav-trigger">Menu<span aria-hidden="true" class="cd-icon"></span></button>
</header>
 
<nav class="cd-primary-nav">
 <ul>
  <li class="cd-label">Navigation</li>
  <li><a href="#0">The team</a></li>
  <!-- 可以有更多的导航项 -->
 </ul>
</nav> <!-- .cd-primary-nav -->
 
<div class="cd-projects-container">
 <ul>
  <li class="single-project">
   <div class="cd-title">
    <h2>Project 1</h2>
   </div> <!-- .cd-title -->
 
   <div class="cd-project-info">
    <button class="cd-scroll">Scroll down</button>
     
    <div class="content-wrapper">
     <p>
      项目描述
     </p>
 
     <!-- 额外的项目信息 -->
    </div>
   </div> <!-- .cd-project-info -->
  </li>
 
  <!-- 其它项目 -->
 </ul>
</div> <!-- .cd-projects-container -->    

.cd-projects-container {
 height: 100%;
 position: relative;
 overflow: hidden;
}
.cd-projects-container .single-project {
 position: absolute;
 top: 0px;
 left: 0px;
 height: 100%;
 width: 100%;
 transition: transform 0.4s;
}
.cd-projects-container .single-project:nth-of-type(2) {
 transform: translateY(33.3333333333%);
}
.cd-projects-container .single-project:nth-of-type(3) {
 transform: translateY(66.6666666667%);
}       

.cd-title {
 height: 33.3333333333%;
}
.cd-title::before {
 /* 背景图片 */
 content: '';
 position: absolute;
 top: 0;
 left: 0;
 height: 300%;
 width: 100%;
 background-position: center center;
 background-repeat: no-repeat;
 background-size: cover;
}
.single-project:nth-of-type(1) .cd-title::before {
 background-image: url(../img/img-1.jpg);
}        

.cd-projects-container .single-project.selected {
 /* 被选择的项目 */
 transform: translateY(0);
}
.cd-projects-container .single-project.selected ~ li {
 /* 隐藏其它项目 */
 transform: translateY(100%);
}        

.cd-project-info {
 position: absolute;
 top: 0;
 left: 0;
 width: 100%;
 height: 100%;
 overflow: auto;
 opacity: 0;
 visibility: hidden;
 transition: opacity 0.4s, visibility 0.4s;
}
.cd-project-info::before {
 /* 用与占位，显示项目图片 */
 content: '';
 display: block;
 height: 100%;
 width: 100%;
 pointer-events: none;
}
.cd-project-info .content-wrapper {
 position: relative;
 z-index: 2;
 padding: 2em 0 3em;
 background-color: #FFFFFF;
}
.selected .cd-project-info {
 opacity: 1;
 visibility: visible;
 transition: opacity 0s, visibility 0s;
}        

.cd-primary-nav {
 position: absolute;
 top: 0;
 left: 0;
 /* height = (100% - 9%) - 9% is the space taken by the projects when the navigation is open */
 height: 91%;
 width: 100%;
 overflow: auto;
 opacity: 0;
}
.cd-primary-nav ul {
 transform: translateY(50px);
 transition: transform 0.4s;
}
.cd-primary-nav.nav-open {
 opacity: 1;
}
.cd-primary-nav.nav-open ul {
 transform: translateY(0);
}
 
.cd-projects-container.nav-open .single-project {
 box-shadow: 0 0 30px rgba(0, 0, 0, 0.5);
 transform: translateY(91%);
}
.cd-projects-container.nav-open .single-project:nth-of-type(2) {
 transform: translateY(94%);
}
.cd-projects-container.nav-open .single-project:nth-of-type(3) {
 transform: translateY(97%);
}