The way to add comments in a CSS file is to use // to wrap the comment content. 1. Comments can be used to illustrate the purpose of the code, separate modules, interpret complex logic, or retain temporary changes, such as / This is the style of the main title /; 2. Comments cannot be nested and do not support // form; 3. When using compression tools, please pay attention to whether the comments will be deleted. The rational use of comments can help improve code readability and team collaboration efficiency.
Adding comments to CSS files is actually quite simple, but many people may not be sure whether the syntax is correct at the beginning. Comments in CSS will not be displayed by the browser, nor will they affect the page effect, but they can help you sort out the code structure, write down the purpose, and even make it easier for others to understand your style sheet.
Use /* */ Incarnate "Invisible Notes"
There is only one way to comment CSS: start with /* and end with */ . The content in the middle is the comment text, such as:
/* This is the style of the main title*/
h1 {
color: #333;
}This method can be written single-line comments or used across multiple lines:
/*
The following style is used for the navigation bar that contains link colors and hover effects*/
nav a {
color: blue;
}You can treat it as a "code description tag", write the author information and project name at the beginning of the file, or add a reminder before a complex pattern, which will save a lot of time when looking back.
Which places are suitable for commenting?
- Module separation : For example, "head style" and "carousel picture settings" are added to the front of large blocks of content to make the entire file more organized.
- Complex logic : If you use some Hack or specially wrapped selectors to solve compatibility problems, it is necessary to write an explanation.
- Temporary changes : Sometimes you change a style but are not sure whether it will be restored in the future. You can use comments to save the old code first instead of deleting it directly.
For example:
/* Temporarily hide the sidebar (2024/09/01) */
/*
.sidebar {
width: 200px;
}
*/This approach is safer and easier to restore than deleting directly.
Pay attention to some small details
- Comments cannot be nested: For example, if you write
/* ... */in a commented code, it will cause parsing errors. - Don't use
//: This is common in JavaScript or C, but not supported in standard CSS. - The compression tool will delete comments: If you use the tool that automatically compresses CSS, remember to confirm whether the comments are retained, otherwise these "tips" in the online version will be gone.
Basically that's it. Although it seems simple, in team collaboration or long-term maintenance, the rational use of comments can really save a lot of communication costs.
The above is the detailed content of How to comment in a CSS file?. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undress AI Tool
Undress images for free
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
How to change text color in CSS?
Jul 27, 2025 am 04:25 AM
To change the text color in CSS, you need to use the color attribute; 1. Use the color attribute to set the text foreground color, supporting color names (such as red), hexadecimal codes (such as #ff0000), RGB values (such as rgb(255,0,0)), HSL values (such as hsl(0,100%,50%)), and RGBA or HSLA with transparency (such as rgba(255,0,0,0.5)); 2. You can apply colors to any element containing text, such as h1 to h6 titles, paragraph p, link a (note the color settings of different states of a:link, a:visited, a:hover, a:active), buttons, div, span, etc.; 3. Most
How to purge unused CSS?
Jul 27, 2025 am 02:47 AM
UseautomatedtoolslikePurgeCSSorUnCSStoscanandremoveunusedCSS;2.IntegratepurgingintoyourbuildprocessviaWebpack,Vite,orTailwind’scontentconfiguration;3.AuditCSSusagewithChromeDevToolsCoveragetabbeforepurgingtoavoidremovingneededstyles;4.Safelistdynamic
What is a stacking context?
Jul 27, 2025 am 03:55 AM
Astackingcontextisaself-containedlayerinCSSthatcontrolsthez-orderofoverlappingelements,wherenestedcontextsrestrictz-indexinteractions;itiscreatedbypropertieslikez-indexonpositionedelements,opacity
Describe different CSS units and when to use them
Jul 27, 2025 am 04:24 AM
In web development, the choice of CSS units depends on design requirements and responsive performance. 1. Pixels (px) are used to fix sizes such as borders and icons, but are not conducive to responsive design; 2. Percentage (%) is adjusted according to the parent container, suitable for streaming layout but attention to context dependence; 3.em is based on the current font size, rem is based on the root element font, suitable for elastic fonts and unified theme control; 4. Viewport units (vw/vh/vmin/vmax) are adjusted according to the screen size, suitable for full-screen elements and dynamic UI; 5. Auto, inherit, initial and other values are used to automatically calculate, inherit or reset styles, which helps to flexibly layout and style management. The rational use of these units can improve page flexibility and responsiveness.
How to use the CSS backdrop-filter property?
Aug 02, 2025 pm 12:11 PM
Backdrop-filter is used to apply visual effects to the content behind the elements. 1. Use backdrop-filter:blur(10px) and other syntax to achieve the frosted glass effect; 2. Supports multiple filter functions such as blur, brightness, contrast, etc. and can be superimposed; 3. It is often used in glass card design, and it is necessary to ensure that the elements overlap with the background; 4. Modern browsers have good support, and @supports can be used to provide downgrade solutions; 5. Avoid excessive blur values and frequent redrawing to optimize performance. This attribute only takes effect when there is content behind the elements.
How to style links in CSS?
Jul 29, 2025 am 04:25 AM
The style of the link should distinguish different states through pseudo-classes. 1. Use a:link to set the unreached link style, 2. a:visited to set the accessed link, 3. a:hover to set the hover effect, 4. a:active to set the click-time style, 5. a:focus ensures keyboard accessibility, always follow the LVHA order to avoid style conflicts. You can improve usability and accessibility by adding padding, cursor:pointer and retaining or customizing focus outlines. You can also use border-bottom or animation underscore to ensure that the link has a good user experience and accessibility in all states.
How to center text in CSS?
Jul 27, 2025 am 03:16 AM
Use text-align:center to achieve horizontal centering of text; 2. Use Flexbox's align-items:center and justify-content:center to achieve vertical and horizontal centering; 3. Single-line text can be vertically centered by setting line-height equal to the container height; 4. Absolute positioning elements can be combined with top: 50%, left: 50% and transform:translate (-50%, -50%) to achieve centering; 5. CSSGrid's place-items:center can also achieve dual-axis centering at the same time. It is recommended to use Flexbox or Grid first in modern layouts.
What are user agent stylesheets?
Jul 31, 2025 am 10:35 AM
User agent stylesheets are the default CSS styles that browsers automatically apply to ensure that HTML elements that have not added custom styles are still basic readable. They affect the initial appearance of the page, but there are differences between browsers, which may lead to inconsistent display. Developers often solve this problem by resetting or standardizing styles. Use the Developer Tools' Compute or Style panel to view the default styles. Common coverage operations include clearing inner and outer margins, modifying link underscores, adjusting title sizes and unifying button styles. Understanding user agent styles can help improve cross-browser consistency and enable precise layout control.
