Chrome's "CSS Overview" panel can be opened by right-clicking the page and clicking CSS overview in More tools to open it. It can list the color usage of the page and help unify the color specifications; display the font family and size distribution, and it is recommended to limit the font types and unify the level; it can also find unused CSS rules to facilitate cleaning of redundant styles, but it is necessary to note that dynamic loading of content may lead to misjudgment.

Chrome's "CSS Overview" panel is a very useful tool, especially if you want to quickly understand CSS usage in a webpage. It can help you find style issues, optimization opportunities, and even find unused CSS.

How to open the CSS Overview panel

First, you need to make sure you are using the latest version of Chrome. Then:

• Right-click on the page and select "Check" to open DevTools
• Click the three dots in the top tab bar and select More tools > CSS overview
• Switch to the "CSS Overview" panel to start analysis

This feature is suitable for front-end developers, website optimization personnel, and even those who are just starting out want to see if the style they write is reasonable.

Check color usage

This section lists all the color values used on the page, including formats such as hexadecimal, RGB, and color names. You can see which colors are used frequently, or if there are too many repetitions or similar colors.

suggestion:

• If you find multiple similar colors, you can consider unifying them into one to improve consistency
• Check for unnecessary transparency settings (such as rgba(0, 0, 0, 0.5) ) that may affect performance or rendering

This can also help you quickly extract color specifications when doing theme switching or designing systems.

Analyze fonts and font sizes

This section shows all the font families, font sizes and their occurrences on the page.

Common phenomena:

• Too many different fonts are used in the page, causing slow loading or visual confusion
• Inconsistent font sizes affect reading experience

suggestion:

• Try to limit the types of fonts, generally no more than 2 to 3 types
• Unify the font size level, such as 24px for the title, 16px for the text, and 14px for the small characters, so that the structure is clearer

If you are doing responsive design, you can also use this panel to check whether the font performance under different screen sizes is reasonable.

Find unused CSS rules

This is a very useful feature, especially for large projects. CSS Overview can list CSS class names that are loaded in the current page but are not actually applied.

Note:

• It will only detect the style used by the visible elements of the current page and will not overwrite the content dynamically inserted by JS
• Therefore, some classes may be lazy to load or controlled through JS, which may be misjudged as "unused" at this time

suggestion:

• Use this feature to clean up redundant styles on critical path pages (such as home page)
• Combined with other tools such as PurgeCSS for a more comprehensive cleaning

If you find many unused classes come from a third-party library, consider introducing them on demand or looking for lighter alternatives.

Basically these common functions. CSS Overview is not particularly complicated, but can easily be ignored. After mastering it, you can indeed save a lot of time in daily debugging and optimization.

The above is the detailed content of How to use Chrome's 'CSS Overview' panel. For more information, please follow other related articles on the PHP Chinese website!