效果预览按下右侧的“点击预览”按钮可以在当前页面预览，点击链接可以全屏预览。https://codepen.io/comehope/pen/QrxxaW可交互视频教程此视频是可以交互的，你可以随时暂停视频，编辑视频中的代码。请用 chrome, safari, edge 打开观看。https://scrimba.com/p/pEgDAM/cgRgQHr源代码下载请从 github 下载。https://github.com/comehope/front-end-daily-challenges/tree/master/021-a-text-sliding-effect-ui代码解读定义 dom，容器中包含 question 和 answer：<div> <p> <span class="question">Who gives you milk?</span> <span class="answer">cow</span> </p></div>居中显示：html, body { height: 100%; display: flex; align-items: center; justify-content: center; background: darkcyan;}设置文本样式：p { width: 400px; height: 2.5em; color: gold; font-size: 24px; border: 2px solid gold; line-height: 2.5em; text-align: center; border-radius: 10px; font-family: sans-serif; letter-spacing: 2px; word-spacing: 2px; box-shadow: 5px 5px 10px rgba(0, 0, 0, 0.2);}设置答案的样式：p { position: relative;}p span { position: absolute; width: 100%; top: 0; left: 0;}p .answer { color: whitesmoke; font-size: 1.1em; text-transform: uppercase; background: rgba(0, 0, 0, 0.1);}增加问题与答案滑动切换的动画效果：p { overflow: hidden;}p span { transition: 0.5s ease-out;}p .question { left: 0;}p:hover .question { left: 100%;}p .answer { left: -100%;}p:hover .answer { left: 0;}dom 中再增加 2 个问题：<div> <p> <span class="question">Who gives you milk?</span> <span class="answer">cow</span> </p> <p> <span class="question">Who likes to eat flies?</span> <span class="answer">frog</span> </p> <p> <span class="question">Who have large claws?</span> <span class="answer">crab</span> </p></div>dom 中增加标题：<div> <h1>Who Am I</h1> <p> <span class="question">Who gives you milk?</span> <span class="answer">cow</span> </p> <p> <span class="question">Who likes to eat flies?</span> <span class="answer">frog</span> </p> <p> <span class="question">Who have large claws?</span> <span class="answer">crab</span> </p></div>设置标题样式：h1 { font-family: sans-serif; color: gold; text-align: center;}最后，用伪元素增加大问号作为装饰背景：h1 { position: relative;}h1::after { content: '?'; position: absolute; top: -0.35em; left: 0; font-size: 25em; transform: rotate(15deg); color: cyan; filter: opacity(0.3); text-shadow: 10px 10px 10px rgba(0, 0, 0, 0.2);}知识点rotate() https://developer.mozilla.org/en-US/docs/Web/CSS/transform-function/rotatefilter https://developer.mozilla.org/en-US/docs/Web/CSS/filtertransition https://developer.mozilla.org/en-US/docs/Web/CSS/transition
