CSS入门_html/css_WEB-ITnose
选择器
1 <!--这个样式用在p元素中-->2 p{3 color: maroon;4 }把CSS放入HTML中
1 <!-- 放入style元素中，但不建议文件多的时候这样做 --> 2 <head> 3 <meta charset="utf-8"> 4 <title> HEAD FIRST CSS</title> 5 <style> 6 p{ 7 color: maroon; 8 } 9 </style>10 </head>为一个或多个页面增加样式：
步骤：
- 取出html文件中的样式规则，把他们放在一个后缀名为.css的文件中。
- 从每个html文件创建一个到css文件的外部链接
- 做好测试
1 <!--这个样式在一个index.css文件中--> 2 p{ 3 color: maroon; 4 } 5 6 7 <!-- 在html文件中 --> 8 <head> 9 10 <meta charset = "utf-8">11 <title>head first Lounge</title>12 13 <!-- 链接到外部样式表的HTML -->14 <link rel="stylesheet" href="index.css">15 16 </head>只能对体中的元素增加样式，所以元素不用作讨论
上图注释：
元素，就会影响到下面阴影部分的所有元素。
长江后浪推前浪，覆盖继承
然而，有些时候，不希望每个元素都继承样式。
但是，还好，浏览器总会使用更特定的规则
1 body{2 font-family:sans-serif;3 }4 5 /* 覆盖掉了从body继承的font-family属性 */6 em{7 font - family:serif;8 }
总是有些段落要特殊点的
不是吗？所以，有了类的存在，就像俱乐部
1 <!-- 在html文件中 -->2 <p class="specil">3 this is a specil people/class;4 </p>5 <p>6 this is 平常的 p;7 </p>
1 /*这个样式在一个index.css文件中*/2 p{3 font-family:sans-serif;4 }5 /*specil类的p ，覆盖掉了从p继承的样式，多个元素同属一个类时，为了一次设置多个元素，可以省略类前的元素名*/6 p.specil{7 color:green;8 }
什么？一个元素加入了多个俱乐部？
没事，选择器总是会选最特定（特定等级相同时选最后的）的样式
1 <!-- 在html文件中 -->2 <p class="specil big small">3 this is a specil people/class;4 </p>
1 /*选择所有段落*/ 2 p{ 3 4 color:black; 5 } 6 /*选择specil类所有成员，比上一个特定点*/ 7 .specil{ 8 color:green; 9 }10 /*这个规则只选specil类中段落，比前一个更特定*/11 p.specil{12 color:green;13 }14 p.specil{15 color:blue;16 }结果：
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
AI Hentai Generator
Generate AI Hentai for free.
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
1376
52
What is the purpose of the <progress> element?
Mar 21, 2025 pm 12:34 PM
The article discusses the HTML <progress> element, its purpose, styling, and differences from the <meter> element. The main focus is on using <progress> for task completion and <meter> for stati
What is the purpose of the <datalist> element?
Mar 21, 2025 pm 12:33 PM
The article discusses the HTML <datalist> element, which enhances forms by providing autocomplete suggestions, improving user experience and reducing errors.Character count: 159
What are the best practices for cross-browser compatibility in HTML5?
Mar 17, 2025 pm 12:20 PM
Article discusses best practices for ensuring HTML5 cross-browser compatibility, focusing on feature detection, progressive enhancement, and testing methods.
What is the purpose of the <meter> element?
Mar 21, 2025 pm 12:35 PM
The article discusses the HTML <meter> element, used for displaying scalar or fractional values within a range, and its common applications in web development. It differentiates <meter> from <progress> and ex
How do I use HTML5 form validation attributes to validate user input?
Mar 17, 2025 pm 12:27 PM
The article discusses using HTML5 form validation attributes like required, pattern, min, max, and length limits to validate user input directly in the browser.
How do I use the HTML5 <time> element to represent dates and times semantically?
Mar 12, 2025 pm 04:05 PM
This article explains the HTML5 <time> element for semantic date/time representation. It emphasizes the importance of the datetime attribute for machine readability (ISO 8601 format) alongside human-readable text, boosting accessibilit
What is the viewport meta tag? Why is it important for responsive design?
Mar 20, 2025 pm 05:56 PM
The article discusses the viewport meta tag, essential for responsive web design on mobile devices. It explains how proper use ensures optimal content scaling and user interaction, while misuse can lead to design and accessibility issues.
What is the purpose of the <iframe> tag? What are the security considerations when using it?
Mar 20, 2025 pm 06:05 PM
The article discusses the <iframe> tag's purpose in embedding external content into webpages, its common uses, security risks, and alternatives like object tags and APIs.
