> For the complete documentation index, see [llms.txt](https://docs.webmix.cc/html-and-css/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.webmix.cc/html-and-css/3.-css/3.25-guan-wu-outline.md).

# 3.23 關於 outline

## 說明

outline(輪廓) 是一個位在 border 邊框(border)外面的線，可以設定粗細、線的類型、顏色、位移。outline 並不會影響周圍的元素。

註：outline 並不能針對某一邊去設定。

## 語法

```css
outline: 1px solid red; /* 預設是 none */
outline-offset: 5px;    /* 設定向內或向外擴展，也可以是 -5px，就會向內縮 */
```

## 範例

{% embed url="<https://codepen.io/carlos411/pen/eYOrYde>" %}


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