CSS: Basic syntax and derived selectors_html/css_WEB-ITnose
This article introduces the basic syntax and derived selectors of CSS.
The code is compiled from w3school: http://www.w3school.com.cn
(1) Basic part:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><meta http-equiv="Content-Language" content="zh-cn" /><head><style type="text/css">h1,h2,h3 {color:red;background-color:#ccc}li strong {font-style:italic;}</style></head><title>CSS基础</title><body> <h1>h1,h2,h3 级标题为CSS样式指定为灰底红字<h1> <h2>h1,h2,h3 级标题为CSS样式指定为灰底红字<h2> <h3>h1,h2,h3 级标题为CSS样式指定为灰底红字<h3> <h4>h4级标题没有被指定样式<h3> <hr/> <!--派生选择器--> <h4>派生选择器允许你根据文档的上下文关系来确定某个标签的样式。</p> <p><strong>我是粗体字，不是斜体字，因为我不在列表当中，所以这个规则对我不起作用</strong></p> <ol> <li><strong>我是斜体字。这是因为 strong 元素位于 li 元素内。</strong></li> <li>我是正常的字体。</li> </ol></body></html>(2) Style "override" rules
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN""http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><meta http-equiv="Content-Language" content="zh-cn" /><head> <style type="text/css"> strong {color: red;} h2 {color: red;} h2 strong {color: blue;} </style></head><title>CSS基础-样式的“覆盖”规则</title><body> <p>The strongly emphasized word in this paragraph is <strong>red</strong>.</p> <h2>This subhead is also red.</h2> <h2>The strongly emphasized word in this subhead is <strong>blue</strong>.</h2></body></html>Rendering:
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