where is the css file-Front-end Q&A-php.cn

CSS (Cascading Style Sheets) is a very important part of web design, used to define and control the appearance and layout of HTML documents. In the development process of the website, the use of CSS files is often involved. So, where are CSS files stored? This article will introduce and answer this question in detail.

What is a CSS file? First of all, we need to understand what a CSS file is. Simply put, a CSS file is a text file used to control the style of a web page. It contains a series of style rules to define the color, layout, font and other visual effects of various elements in the web page. CSS files are usually saved in the .css file format and can be referenced through links in HTML documents.

The storage location of CSS files The storage location of CSS files can be divided into two situations: internal style sheets and external style sheets.

(1) Internal style sheet

Internal style sheet refers to writing CSS code directly in the tag in the HTML document.

CSS文件在哪里 p { color: red; font-size: 16px; } 这是一段红色的文字，字体大小为16px。

Copy after login As shown in the above code, the CSS style added through the tag in the tag is called an internal style sheet. In actual development, the use of internal style sheets is less common because repeated CSS code in each HTML file will cause redundancy and increase the file size.

(2) External style sheet

External style sheet refers to saving the CSS code in a separate .css file and referencing it in the HTML document through the tag.

CSS文件在哪里 这是一段红色的文字，字体大小为16px。

Copy after login As shown in the above code, the href attribute in the tag specifies the path to the external .css file. This path can be a relative path or an absolute path. In actual development, CSS styles are usually saved in a separate .css file, which can improve the readability and maintainability of the file.

How to reference CSS files There are two ways to reference CSS files: direct reference and reference through CDN.

(1) Direct reference

In local development, we usually introduce CSS files into HTML documents by direct reference. CSS files can be referenced via relative or absolute paths.

The method of relative path reference is as follows:

CSS文件在哪里 这是一段红色的文字，字体大小为16px。

Copy after login When referencing CSS files through relative paths, it should be noted that the starting position of the path is the path where the HTML document is located. Therefore, we can use ../ to return to the previous path.

The absolute path reference method is as follows:

CSS文件在哪里 这是一段红色的文字，字体大小为16px。

Copy after login When referencing the CSS file through the absolute path, it should be noted that the path of the CSS file is a complete URL link and needs to contain http:// Or https:// and other protocol headers.

(2) Reference through CDN

CDN (Content Delivery Network) refers to the content distribution network, which can deliver resources to visitors faster by deploying resources on multiple node servers around the world. Provide file download service. In actual development, we can improve the loading speed and usability of the page by introducing the CSS file provided by the CDN into the HTML document.

The CDN reference method is as follows:

CSS文件在哪里 这是一段红色的文字，字体大小为16px。

Copy after login When referencing a CSS file through a CDN, you need to replace the href attribute in the tag with the CSS file link address provided by the CDN.

Summary In the development process of the website, the use of CSS files is necessary. From this article we can see that the storage location of CSS files can be divided into internal style sheets and external style sheets. In order to improve the readability and maintainability of files, we usually use external style sheets. CSS files can be referenced directly or through CDN. No matter which reference method is used, as long as the path is correct, the CSS file can be successfully referenced.