In the previous article "What are HTML elements? A brief discussion on the grammatical rules of elements" takes everyone to understand HTML elements and grammatical rules. The following article will introduce you to CSS syntax and learn about the three ways to use CSS style sheets. Let’s take a look! !
1. CSS syntax
CSS rule set (rule-set) consists of selectors and declaration blocks
Example explanation
p
is the selector in CSS (it points to the HTML element to be styled :<p></p>
)
color
is the attribute, red
is the attribute value
text-align
is the attribute, center
is the attribute value
Code example:
<html> <head> <style> p { color:red; text-align:center; } </style> </head> <body> <p>php</p> <p>php中文网</p> </body> </html>
Rendering:
CSS Example:
CSS declarations always begin with a semicolon (;
) ends, the statement is always enclosed in curly brackets ({}
):
p { color:red; text-align:center; }
Comments are used to explain your code, and you can edit it at will, the browser will ignore it.
CSS comments start with /*
and end with */
. Examples are as follows:
/*这是个注释*/ p { text-align:center; /*这是另一个注释*/ color:black; font-family:arial; }
2. How about CSS Instructions?
How to use CSS: Editing tools
There are generally three ways to use any text editing tool style sheet:
1) Document header Insert : Suitable for single web application
2) Insert in line: Suitable for CSS
3 in one or two places on the page )External link style file: Suitable for multiple web pages that use CSS
There are different ways to use css in HTML web pages and different ways to call css
1. Header Insert style internally
<style type="text/css">……</style>
Code example:
<html> <head> <title>中文网(php.com)</title> <style type="text/css"> body {background-color:yellow;} h1 {font-size:36pt;} h2 {color:blue;} p {margin-left:50px;} </style> </head> <body>
Note: Here the type attribute of the style object is set to”text/css
” is not supported by browsers that ignore stylesheets.
2. Inline insertion style
<p style=“font-size:16pt;color:blue”>蓝色16号文字</p>
adopts <style style="background-color: rgb(248, 248, 248);">font-size:16pt;color:blue"> The format of ;</style>
writes the style in any line in HTML, which is more convenient and flexible.
3. External link style
First create an external style sheet file (.css
), and then use the HTML link object
<head> <title>中文网(php.com)</title> <link rel=stylesheet href="http://www.php.cn/php.cn" type="text/css"> </head>
This method is very suitable for defining multiple documents at the same time. It enables multiple documents to use the same style at the same time, thereby reducing a lot of redundant code.
In XML, you should add it in the declaration area as shown in the following example:
<? xml-stylesheet type="text/css" href="http://www.php.cn/php.css" ?>
Define an internal style block object (Embedding a Style Block)
You can insert a <style>...</style># between the
and
tags in your HTML document. ##Block object.
Notes
- Be careful<p></p>
The above is the detailed content of What is CSS syntax? Detailed introduction to usage and rules. For more information, please follow other related articles on the PHP Chinese website!

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

Notepad++7.3.1
Easy-to-use and free code editor

Safe Exam Browser
Safe Exam Browser is a secure browser environment for taking online exams securely. This software turns any computer into a secure workstation. It controls access to any utility and prevents students from using unauthorized resources.

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),

MantisBT
Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.