单纯的CSS文件
当我们创建一个CSS文档时，经常遇到样式定义冲突的情况，这时遵从以下规则。
-
当一个HTML元素被定义多重CSS样式时，只有最后一个是可见的。如：
p {color: red}p {color: blue}/* 效果为蓝色 */ 当CSS样式定义在DOM元素的父级节点时，所有的自己元素都会继承该样式。
-
同一元素存在不同的选择方式时，根据权重进行计算：
- ID属性=100
- class属性=10
- HTML标签=1
使用 ！important 标记，可以把选择器优先级提高到最前。
<body><p id="target" class="target">Hello World</p></body><style> p#target {color: black !important} p#target {color: red} p.target {color: blue} p {color: tomato} /* Black color is applied */</style> 在HTML文件中使用CSS
有多种方法可以把CSS文件导入到HTML中，通常在HTML中出现位置的顺序为：
- 在部分通过导入外部样式
- 在部分直接写入
- 在CSS部分通过 @import 导入外部样式
- 直接定义在HTML标签中的style属性
然而，优先级的顺序确是：
- 直接定义在HTML标签中的style属性
- 在部分直接写入的
- 在CSS部分通过 @import 导入的外部样式
- 在部分通过导入的外部样式
在以下代码片段中四种导入CSS的方法都使用了，最终呈现出的效果，是级别最高的p标签中的style定义。除非，有 !important 在其他定义方式中出现。
<!DOCTYPE html><html> <head> /* Link in head */ <link rel="stylesheet" href="css/style.css"/> /* Style tag in head */ <style> p {color: tomato} </style> /* @import in CSS area */ <style> @import url("css/style.css"); </style> </head> <body> /* Style attribute in HTML element */ <p style="color: red">Hello World</p> </body></html> 
Difficulty in updating caching of official account web pages: How to avoid the old cache affecting the user experience after version update?Mar 04, 2025 pm 12:32 PMThe official account web page update cache, this thing is simple and simple, and it is complicated enough to drink a pot of it. You worked hard to update the official account article, but the user still opened the old version. Who can bear the taste? In this article, let’s take a look at the twists and turns behind this and how to solve this problem gracefully. After reading it, you can easily deal with various caching problems, allowing your users to always experience the freshest content. Let’s talk about the basics first. To put it bluntly, in order to improve access speed, the browser or server stores some static resources (such as pictures, CSS, JS) or page content. Next time you access it, you can directly retrieve it from the cache without having to download it again, and it is naturally fast. But this thing is also a double-edged sword. The new version is online,
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 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 to efficiently add stroke effects to PNG images on web pages?Mar 04, 2025 pm 02:39 PMThis article demonstrates efficient PNG border addition to webpages using CSS. It argues that CSS offers superior performance compared to JavaScript or libraries, detailing how to adjust border width, style, and color for subtle or prominent effect
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 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
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
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 Mac version
God-level code editing software (SublimeText3)
SublimeText3 Linux new version
SublimeText3 Linux latest version
SecLists
SecLists is the ultimate security tester's companion. It is a collection of various types of lists that are frequently used during security assessments, all in one place. SecLists helps make security testing more efficient and productive by conveniently providing all the lists a security tester might need. List types include usernames, passwords, URLs, fuzzing payloads, sensitive data patterns, web shells, and more. The tester can simply pull this repository onto a new test machine and he will have access to every type of list he needs.
WebStorm Mac version
Useful JavaScript development tools
SublimeText3 English version
Recommended: Win version, supports code prompts!
