CSS is a style sheet language used for web design that controls how HTML or XHTML appears and is formatted. CSS is an important part of WEB front-end development, and mastering CSS is an essential skill for today's front-end development.
So, how to use CSS? This article will introduce the basic usage and common rules of CSS to help beginners quickly master CSS.
- Create CSS file
First, you need to create a CSS file. It can be created using a text editor (such as Notepad, Sublime Text, etc.) and saved as a .css file. Typically, you save the CSS file in a separate file and then use the element in HTML to connect the CSS file to the HTML page. - CSS Selectors
The most common selector in CSS is the element selector, which represents the type of markup you want to apply the style to (such as h1, p, etc.). Prefixing the selector name with "#" indicates an ID selector, while prefixing the name with "." indicates a class selector.
For example, to add a style to the element with the id of "header", the CSS code is as follows:
#header{ background-color: #ccc; width: 100%; }
-
CSS properties
In CSS, properties Used to specify the style to be applied to the element. For example, the following CSS style will set the font size to 16 pixels for all p tags:p{ font-size: 16px; }
The property can also accept multiple values. For example, the following CSS rule will set 4 values for the margin attribute of an element:
margin: 10px 5px 15px 20px;
The first value is top padding, the second is right padding, the third is bottom padding, and the fourth is Left padding. If left padding is not provided, it defaults to the same as right padding; if bottom padding is not provided, it defaults to the same as top padding.
- CSS Style Sheet
For large websites, it is recommended to divide the style sheet into several parts for better management. The most common approach is to divide the website's style into various different style sheets, each controlling a different part of the website.
For example, a typical website may have some style sheets: the website global style sheet is responsible for the style of the entire website, navigation bar, header, footer, etc.; another style sheet is responsible for the internal pages. Styles; there is also a typical stylesheet responsible for responsive design, allowing the website to adapt to the different screen sizes of various devices.
- Using CSS frameworks and preprocessors
The CSS framework is a set of common style sheets and rules that can speed up website styling. Preprocessors are tools that enhance the functionality of CSS, such as LESS, SASS, and Stylus. They allow developers to control the style of the website using variables, functions, and nested rules.
For example, here are some popular CSS frameworks:
-Bootstrap: One of the most popular and widely used CSS frameworks, it contains various components including forms, navigation, Buttons, grids and layouts.
-Foundation: Another very popular CSS framework that integrates many layout and UI components and provides customization options. Provides more layout customization than Bootstrap.
-Materialize CSS: A CSS framework based on Material Design, with many native controls, it is a very good-looking framework.
Summary
This article introduces the basic usage and common rules of CSS. In addition, there are many other CSS properties and considerations that need to be mastered in practical work. Practice is the best way to learn, by implementing projects and trying different methods to improve your understanding and application of CSS.
The above is the detailed content of how to use css. For more information, please follow other related articles on the PHP Chinese website!

The article discusses useEffect in React, a hook for managing side effects like data fetching and DOM manipulation in functional components. It explains usage, common side effects, and cleanup to prevent issues like memory leaks.

Lazy loading delays loading of content until needed, improving web performance and user experience by reducing initial load times and server load.

Higher-order functions in JavaScript enhance code conciseness, reusability, modularity, and performance through abstraction, common patterns, and optimization techniques.

The article discusses currying in JavaScript, a technique transforming multi-argument functions into single-argument function sequences. It explores currying's implementation, benefits like partial application, and practical uses, enhancing code read

The article explains useContext in React, which simplifies state management by avoiding prop drilling. It discusses benefits like centralized state and performance improvements through reduced re-renders.

The article explains React's reconciliation algorithm, which efficiently updates the DOM by comparing Virtual DOM trees. It discusses performance benefits, optimization techniques, and impacts on user experience.Character count: 159

Article discusses preventing default behavior in event handlers using preventDefault() method, its benefits like enhanced user experience, and potential issues like accessibility concerns.

The article discusses the advantages and disadvantages of controlled and uncontrolled components in React, focusing on aspects like predictability, performance, and use cases. It advises on factors to consider when choosing between them.


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

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

Atom editor mac version download
The most popular open source editor

Dreamweaver Mac version
Visual web development tools

PhpStorm Mac version
The latest (2018.2.1) professional PHP integrated development tool

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.
