html - CSS 不透明度过渡一次淡入一行

Question

我正在尝试使用过渡来改变不透明度并依次淡出三行。我的页面上有一个带有 3 p 和强标签的 div，我试图在大约 2 秒后淡入每行，中间间隔 0.5 秒。这是我正在尝试的只有 div 和 css 的 fiddle 。我已经搜索了这个主题并尝试了 css 和 js 的一些变体，但无论我做什么，线条开始时都是完全可见的，但如果我通过检查器切换不透明度，它就会进出过渡(也没有延迟因为某些原因)。任何帮助将不胜感激，谢谢!

http://jsfiddle.net/7uR8z/5047/

<div class=".Index-gallery-item-content-body">  
    <p>
        <strong>Test Line 1</strong>
    </p>

    <p>
        <strong>Line 2 Here</strong>
    </p>

    <p>
        <strong>Awesome Line 3</strong>
    </p>

</div>

CSS:

.Index-gallery-item-content-body p
{
    opacity:0
}

.Index-gallery-item-content-body p:nth-child(1)
{ 
    opacity:1;
    transition-delay: 2.5s;
    -webkit-transition: opacity 1s ease-in-out;
    -moz-transition: opacity 1s ease-in-out;
    -ms-transition: opacity 1s ease-in-out;
    -o-transition: opacity 1s ease-in-out;
    transition: opacity 1s ease-in-out;
}

.Index-gallery-item-content-body p:nth-child(2)
{
    opacity:1;
    transition-delay: 3s;
    -webkit-transition: opacity 1s ease-in-out;
    -moz-transition: opacity 1s ease-in-out;
    -ms-transition: opacity 1s ease-in-out;
    -o-transition: opacity 1s ease-in-out;
    transition: opacity 1s ease-in-ou
}

.Index-gallery-item-content-body p:nth-child(3)
{
    opacity:1;
    transition-delay: 3.5s;
    -webkit-transition: opacity 1s ease-in-out;
    -moz-transition: opacity 1s ease-in-out;
    -ms-transition: opacity 1s ease-in-out;
    -o-transition: opacity 1s ease-in-out;
    transition: opacity 1s ease-in-ou
}

Answer 1

您正在寻找动画而不是过渡:

.Index-gallery-item-content-body p {
  opacity: 0
}

.Index-gallery-item-content-body p:nth-child(1) {
  animation: change 2s ease-in-out forwards;
}

.Index-gallery-item-content-body p:nth-child(2) {
  animation: change 2s ease-in-out forwards;
  animation-delay: 2.5s;
}

.Index-gallery-item-content-body p:nth-child(3) {
  animation: change 2s ease-in-out forwards;
  animation-delay: 5s;
}

@keyframes change {
  to {
    opacity: 1
  }
}

<div class="Index-gallery-item-content-body">
  <p>
    <strong>Test Line 1</strong>
  </p>
  <p>
    <strong>Line 2 Here</strong>
  </p>
  <p>
    <strong>Awesome Line 3</strong>
  </p>
</div>