如何用纯 CSS 创作在文本前后穿梭的边框

我会带着你远行 2022-04-15 05:43 87阅读 0赞

![1504257-20181122111016640-1801954439.png][]

## 效果预览 ##

[在线演示][Link 1]

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/qYepNv][https_codepen.io_comehope_pen_qYepNv]

## 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/cQ73Vt8][https_scrimba.com_p_pEgDAM_cQ73Vt8]

## 源代码下载 ##

[在线下载][Link 2]

每日前端实战系列的全部源代码请从 github 下载：

[https://github.com/comehope/front-end-daily-challenges][https_github.com_comehope_front-end-daily-challenges]

## 代码解读 ##

定义 dom，容器中包含文本：

<div class="warning">ERROR 404</div>

居中显示：

body {
      margin: 0;
      height: 100vh;
      display: flex;
      align-items: center;
      justify-content: center;
      background-color: rgb(20%, 20%, 20%);
    }

定义文字样式：

.warning {
        color: whitesmoke;
        font-size: 100px;
        font-family: sans-serif;
        font-weight: bold;
    }

用伪元素定义边框尺寸：

.warning {
        position: relative;
        padding: 0.6em 0.4em;
    }
    
    .warning::before,
    .warning::after {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        border: 0.2em solid;
        box-sizing: border-box;
    }

把边框分为两部分，拼在一起：

.warning::before,
    .warning::after {
        border: 0.2em solid transparent;
        color: orangered;
    }
    
    .warning::before {
        border-top-color: currentColor;
        border-right-color: currentColor;
    }
    
    .warning::after {
        border-bottom-color: currentColor;
        border-left-color: currentColor;
    }

把上边框和右边框下沉一层：

.warning::before {
        z-index: -1;
    }

为下边框和在边框加上阴影：

.warning::after {
        box-shadow: 0.3em 0.3em 0.3em rgba(20%, 20%, 20%, 0.8);
    }

最后，让边框转起来：

.warning::before,
    .warning::after {
        animation: rotating 10s infinite;
    }
    
    @keyframes rotating {
        to {
            transform: rotate(360deg);
        }
    }

大功告成！

原文地址：[https://segmentfault.com/a/1190000015045700][https_segmentfault.com_a_1190000015045700]

[1504257-20181122111016640-1801954439.png]: /images/20220415/b6320e0d5d5f409bb8957424a9575412.png
[Link 1]: https://www.jqhtml.com/yanshi?demourl=%2Fwp-content%2Fuploads%2F2018%2F11%2Ffront-end-daily-challenges-master%2F034-box-border-stacking-effect&demotitle=%E7%BA%AF%20CSS%20%E5%88%9B%E4%BD%9C%E5%9C%A8%E6%96%87%E6%9C%AC%E5%89%8D%E5%90%8E%E7%A9%BF%E6%A2%AD%E7%9A%84%E8%BE%B9%E6%A1%86
[https_codepen.io_comehope_pen_qYepNv]: https://codepen.io/comehope/pen/qYepNv
[https_scrimba.com_p_pEgDAM_cQ73Vt8]: https://scrimba.com/p/pEgDAM/cQ73Vt8
[Link 2]: http://www.jqhtml.com/19290.html
[https_github.com_comehope_front-end-daily-challenges]: https://github.com/comehope/front-end-daily-challenges
[https_segmentfault.com_a_1190000015045700]: https://segmentfault.com/a/1190000015045700