CSS Conditional Rules Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article Like Report CSS Conditional Rules apply CSS styles only when certain conditions are met. So the condition here can be either true or false and based on the statements/style will get executed. These rules start with the @ symbol and are part of CSS at-rules.The main conditional rules include:@supports@media@document1. CSS Supports RuleThe @supports rule in CSS allows you to apply styles only if the browser supports a specific CSS property or feature.Syntax:@supports ("condition") { /* Style to apply */} html <!--Driver Code Starts--> <html> <head> <!--Driver Code Ends--> <style> @supports (display: grid) { section h1 { background-color: green; color: white; padding: 15px; } } </style> <!--Driver Code Starts--> </head> <body> <section> <h1>GeeksforGeeks</h1> <h3>A computer science portal for geeks</h3> </section> </body> </html> <!--Driver Code Ends--> The @supports rule checks if the browser supports the display: grid property.If supported, it applies the specified styles to the <h1> element within the <section>, changing its background color to green, text color to white, and adding padding.2. CSS Media RuleThe @media rule in CSS applies styles based on media queries, allowing for responsive design that adapts to different devices and screen sizes.Syntax: @media screen and ("condition") { /* Style to apply */} html <!--Driver Code Starts--> <html> <head> <!--Driver Code Ends--> <style> @media screen and (max-width: 700px) { section { background-color: green; color: white; padding: 15px; } } </style> <!--Driver Code Starts--> </head> <body> <section> <h1>GeeksforGeeks</h1> <h3>A computer science portal for geeks</h3> </section> </body> </html> <!--Driver Code Ends--> The @media rule checks if the device's screen width is 700 pixels or less.If this condition is met, it applies the specified styles to the <section> element, changing its background color to green, text color to white, and adding padding.3. CSS Document Rule The @document rule in CSS is designed to apply styles to specific URLs or sets of URLs. However, it is currently experimental and primarily supported only in Firefox with the -moz- prefix. As a result, it is not recommended for cross-browser use.Syntax: @-moz-document url("YOUR-URL") { /* Style to apply */} html <!--Driver Code Starts--> <html> <head> <!--Driver Code Ends--> <style> @-moz-document url("http://localhost/GfG/document-rule.html") { section h1 { background-color: green; color: #fff; padding: 15px; } } </style> <!--Driver Code Starts--> </head> <body> <section> <h1>GeeksforGeeks</h1> <h3>A computer science portal for geeks</h3> </section> </body> </html> <!--Driver Code Ends--> The @-moz-document rule targets the specific URL "http://localhost/GfG/document-rule.html".Within this URL, it applies styles to the <h1> element inside the <section>, setting a green background, white text color, and padding.Note: The @document rule is not widely supported across browsers; currently, it is primarily implemented in Firefox using the @-moz-document prefixBest Practices for Using CSS Conditional RulesUse the @supports rule to apply styles only if the browser supports specific CSS features, ensuring fallback for unsupported browsers.Leverage the @media rule for responsive design, targeting specific screen sizes or device characteristics.Avoid over-reliance on experimental rules like @document, as they lack cross-browser support. Comment More infoAdvertise with us Next Article CSS Introduction A aakashpawar1999 Follow Improve Article Tags : Technical Scripter Web Technologies CSS Web technologies CSS-Properties +1 More Similar Reads CSS Tutorial CSS stands for Cascading Style Sheets. It is a stylesheet language used to style and enhance website presentation. CSS is one of the three main components of a webpage, along with HTML and JavaScript.HTML adds Structure to a web page.JavaScript adds logic to it and CSS makes it visually appealing or 7 min read CSS Introduction CSS (Cascading Style Sheets) is a language designed to simplify the process of making web pages presentable.It allows you to apply styles to HTML documents by prescribing colors, fonts, spacing, and positioning.The main advantages are the separation of content (in HTML) and styling (in CSS) and the 4 min read CSS Syntax CSS is written as a rule set, which consists of a selector and a declaration block. 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