:first-child
Baseline Widely available *
This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015年7月.
* Some parts of this feature may have varying levels of support.
嘗試一下
p { font-weight: bold; } li:first-child { border: 2px solid orange; } <p>田徑冠軍：</p> <ul> <li>Adhemar da Silva</li> <li>Wang Junxia</li> <li>Wilma Rudolph</li> <li>Babe Didrikson-Zaharias</li> <li>Betty Cuthbert</li> <li>Fanny Blankers-Koen</li> <li>Florence Griffith-Joyner</li> <li>Irena Szewinska</li> <li>Jackie Joyner-Kersee</li> <li>Shirley Strickland</li> <li>Carl Lewis</li> <li>Emil Zatopek</li> <li>Haile Gebrselassie</li> <li>Jesse Owens</li> <li>Jim Thorpe</li> <li>Paavo Nurmi</li> <li>Sergei Bubka</li> <li>Usain Bolt</li> </ul> 語法
css
:first-child { /* ... */ } 範例
基本範例
HTML
html
<div> <p>這段文字被選取了！</p> <p>這段文字沒有被選取。</p> </div> <div> <h2>這段文字沒有被選取：它不是一個 `p` 元素。</h2> <p>這段文字沒有被選取。</p> </div> CSS
css
p:first-child { color: lime; background-color: black; padding: 5px; } 結果
為列表設定樣式
HTML
html
<ul> <li>項目 1</li> <li>項目 2</li> <li> 項目 3 <ul> <li>項目 3.1</li> <li>項目 3.2</li> <li>項目 3.3</li> </ul> </li> </ul> CSS
css
ul li { color: blue; } ul li:first-child { color: red; font-weight: bold; } 結果
規範
| Specification |
|---|
| Selectors Level 4 # first-child-pseudo |