css redundant hiding

CSS is a language used to beautify web page styles. With the continuous development of web page technology, CSS has become more and more mature. However, in practice we often encounter a problem: redundant CSS code. Although these codes may seem harmless, they can significantly increase page load times, slow down web page performance, and may even cause browser crashes. Therefore, we need to take measures to hide these redundant CSS codes.

What is redundant CSS

The so-called redundant CSS, in layman’s terms, is the style code defined in CSS but not used in the actual page. These redundant CSS may be more complex structures, containing many selectors and properties, or just some inconspicuous small code blocks. However, they all have a problem: they are not used by the page, but occupy the space of the browser.

Why should redundant CSS be hidden?

Excessive CSS will slow down page loading. The browser will first download the HTML page and then render the CSS and JavaScript files required for the page. If there is a lot of redundant CSS code, the browser will need to download more files, which will cause slower page load times. On mobile devices, this problem is even more severe because most mobile devices have much less bandwidth and processing power than desktop devices.

Excessive CSS can also cause browser performance to degrade. The browser needs to parse the CSS and apply it to the page elements. If there is a large amount of redundant CSS code, more time and resources will be spent in the parsing process, which can cause page freezes or browser crashes.

How to hide redundant CSS

There are several ways to hide redundant CSS, and I will introduce three of them below.

Method 1: Manually remove useless CSS

This method is relatively simple, but it requires you to patiently check each CSS file and look for unnecessary code fragments. It is suitable for small websites or projects. To manually remove useless CSS, follow these steps:

1. Copy the contents of all CSS files into a text editor.
2. Open the corresponding HTML file, find the page elements, and then find the corresponding CSS code.
3. Continuously delete some CSS code and use the browser inspection tool to see if it will affect the layout and style of the page.
4. If a CSS code block seems to be of no use, you can delete it and save the CSS file.

However, this method has some disadvantages. First, it takes a long time to find and remove unnecessary CSS code. Secondly, if the website is very large, it may be difficult to find all the CSS files. Finally, if you accidentally delete a block of CSS code, it will be very difficult to recover.

Method 2: Use tools to automatically delete useless CSS

If your website is relatively large, it may be very difficult to manually delete useless CSS. At this point, you can use tools to automatically detect and remove redundant CSS. These tools use different algorithms and techniques to identify unused blocks of code, making them more efficient than manually finding and removing them.

The process of using tools to automatically remove useless CSS is relatively simple. Here are the general steps:

1. Open the tool and provide the path to the CSS file.
2. Start the program that scans and detects CSS files.
3. The tool will detect CSS files and remove unused code blocks.
4. Finally, the tool will generate an updated CSS file and you will need to update your website to use the new file.

The disadvantage of the tool automatically removing useless CSS is the problem of style loss. Sometimes tools don't accurately identify which blocks of CSS code are actually not used, which can cause issues with page styling. Therefore, when using this method, you need to double-check the updated CSS file to ensure that the page still displays correctly.

Method 3: Use CDN to accelerate loading of CSS

Finally, using a CDN (content distribution network) can speed up the loading of CSS files and reduce unnecessary code. By using a CDN, you can serve all the content your website needs using servers running from multiple locations. If a user is far away from a CDN server, they will be able to get files from the nearest server, which will significantly increase loading speeds.

Using a CDN can help you reduce the size and number of CSS files and make pages load faster. However, this method requires some configuration and skills, so it may not be suitable for everyone.

Conclusion

In this article, we looked at how redundant CSS code affects page performance and explored three ways to hide them. Manually removing useless CSS requires patience but works for smaller websites or projects. Using tools to automatically detect and remove useless CSS can save you time, but you still need to check your updated CSS files to ensure they are correct. Finally, using a CDN can help you speed up loading of CSS files and reduce unnecessary code. Please choose the method that suits your website and project, and hide redundant CSS code as much as possible.

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