First explain the priority of styles. There are three styles:
1. External style sheet
Example:
<!-- 外部样式 bootstrap.min.css --> <link href="css/bootstrap.min.css" rel="stylesheet" type="text/css">
2. Internal style sheet
Example:
<head> <style type="text/css"> /*内部样式*/ h1 {color:blue;} </style> </head>
3. Inline style
Example:
<h1 id="样式测试">样式测试</h1>
Although inline styles can flexibly change the style of a certain tag independently, it is still recommended not to use inline styles as much as possible. Because although this is more intuitive, it does not conform to the design idea of separation of structure and performance.
Generally speaking, the priority of the above three styles is as follows:
Inline style>Internal style>External style
Priority of selector :
The types of selectors can be divided into three types, namely:
1. Tag name selector such as h1{}.
2. Class selector such as .test{}.
3.ID selector such as #test{}.
At the same time, you need to consider the inline style sheet, that is, writing inside the tag.
Here we use the numbers 1000, 100, 10, 1 to represent the weights of the above three selectors and inline style sheets. The larger the number, the greater the weight, which means the higher the priority.
The weights of each selector are as follows:
1. The weight of the inline style sheet is the highest, set to 1000;
2. The weight of the ID selector is second. , set to 100
3. The weight of the Class class selector is third, set to 10
4. The weight of the HTML tag selector is the lowest, set to 1
Example:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <style type="text/css"> /* 内部样式 */ #blueP p { /* 权值 = 100+1=101 */ color:blue; } #blueP .red { /* 权值 = 100+10=110 */ color:red; } #blueP p span { /* 权值 = 100+1+1=102 */ color:yellow; } #blueP span { /* 权值= 100+1=101 */ color:black; } </style> </head> <body> <div id="blueP"> <p class="red">优先级测试 <span>优先级测试</span> </p> <p>优先级测试</p> </div> </body> </html>
The results displayed on Firefox, IE10, and Chrome browser pages are as follows:
The content within the tag is displayed in red
The content within the tag is displayed in yellow
The last
In addition, in the same set of attribute settings, the rules marked with "!important" have the highest priority. The example is as follows:
<head> <style type="text/css"> /*内部样式 */ #redp p { color:red !important; /* 优先级最大*/ color:blue; } </style> </head> <body> <div id="redp"> <p>!important测试</p> </div> </body> </html>
The page display results in Firefox, IE10, and Chrome are as follows:
The content in the
tag is displayed in red
Other supplements:
1. The greater the weight of the selector, the higher the priority;
2. When the weights are equal, the style sheet settings that appear later will be higher than those that appear first. The style sheet setting that appears has a higher priority;
3. The inherited CSS style has a lower priority than the CSS style specified later
4. The descendant selector and group selector are the tag names. The extended applications of selectors, class selectors and ID selectors will not be introduced here.
First explain the priority of styles. There are three styles:
1. External style sheet
Example:
<!-- 外部样式 bootstrap.min.css --> <link href="css/bootstrap.min.css" rel="stylesheet" type="text/css">
2. Internal style sheet
Example:
<head> <style type="text/css"> /*内部样式*/ h1 {color:blue;} </style> </head>
3. Inline style (Inline style)
Example:
<h1 id="样式测试">样式测试</h1>
Although inline styles can flexibly change the style of a certain label independently, it is still recommended not to use inline styles as much as possible. Because although this is more intuitive, it does not conform to the design idea of separation of structure and performance.
Generally speaking, the priority of the above three styles is as follows:
Inline style>Internal style>External style
Priority of selector :
The types of selectors can be divided into three types, namely:
1. Tag name selector such as h1{}.
2. Class selector such as .test{}.
3.ID selector such as #test{}.
At the same time, you need to consider the inline style sheet, that is, writing inside the tag.
Here we use the numbers 1000, 100, 10, 1 to represent the weights of the above three selectors and inline style sheets. The larger the number, the greater the weight, which means the higher the priority.
The weights of each selector are as follows:
1. The weight of the inline style sheet is the highest, set to 1000;
2. The weight of the ID selector is second. , set to 100
3. The weight of the Class class selector is third, set to 10
4. The weight of the HTML tag selector is the lowest, set to 1
Example:
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <style type="text/css"> /* 内部样式 */ #blueP p { /* 权值 = 100+1=101 */ color:blue; } #blueP .red { /* 权值 = 100+10=110 */ color:red; } #blueP p span { /* 权值 = 100+1+1=102 */ color:yellow; } #blueP span { /* 权值= 100+1=101 */ color:black; } </style> </head> <body> <div id="blueP"> <p class="red">优先级测试 <span>优先级测试</span> </p> <p>优先级测试</p> </div> </body> </html>
The results displayed on Firefox, IE10, and Chrome browser pages are as follows:
The content within the tag is displayed in red
The content within the tag is displayed in yellow
The last
另外在同一组属性设置中标有“!important”规则的优先级最大，示例如下：
<head> <style type="text/css"> /*内部样式 */ #redp p { color:red !important; /* 优先级最大*/ color:blue; } </style> </head> <body> <div id="redp"> <p>!important测试</p> </div> </body> </html>
在火狐，IE10，Chrome浏览器页面显示结果如下：
标签里的内容显示为红色
其他补充：
1.选择器的权值越大优先级越高；
2.当权值相等时，后出现的样式表设置比先出现的样式表设置优先级高；
3.继承的CSS 样式优先级低于后来指定的CSS 样式
4.后代选择器和群组选择器是对标签名选择器、类选择器和ID选择器的扩展应用，在此就不介绍了。
What is the purpose of the <datalist> element?Mar 21, 2025 pm 12:33 PMThe article discusses the HTML <datalist> element, which enhances forms by providing autocomplete suggestions, improving user experience and reducing errors.Character count: 159
What is the purpose of the <progress> element?Mar 21, 2025 pm 12:34 PMThe 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
How do I use HTML5 form validation attributes to validate user input?Mar 17, 2025 pm 12:27 PMThe article discusses using HTML5 form validation attributes like required, pattern, min, max, and length limits to validate user input directly in the browser.
What is the purpose of the <iframe> tag? What are the security considerations when using it?Mar 20, 2025 pm 06:05 PMThe 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.
What is the purpose of the <meter> element?Mar 21, 2025 pm 12:35 PMThe 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
What is the viewport meta tag? Why is it important for responsive design?Mar 20, 2025 pm 05:56 PMThe 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 are the best practices for cross-browser compatibility in HTML5?Mar 17, 2025 pm 12:20 PMArticle discusses best practices for ensuring HTML5 cross-browser compatibility, focusing on feature detection, progressive enhancement, and testing methods.
How do I use the HTML5 <time> element to represent dates and times semantically?Mar 12, 2025 pm 04:05 PMThis 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
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
SublimeText3 English version
Recommended: Win version, supports code prompts!
DVWA
Damn Vulnerable Web App (DVWA) is a PHP/MySQL web application that is very vulnerable. Its main goals are to be an aid for security professionals to test their skills and tools in a legal environment, to help web developers better understand the process of securing web applications, and to help teachers/students teach/learn in a classroom environment Web application security. The goal of DVWA is to practice some of the most common web vulnerabilities through a simple and straightforward interface, with varying degrees of difficulty. Please note that this software
mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),
Notepad++7.3.1
Easy-to-use and free code editor
PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool
