Free CSS Pseudo-Element Generator for :before and :after Shapes—
gemini-3.0-flash
Create and customize CSS :before and :after pseudo-elements with a real-time visual builder. Generate clean CSS code for shapes, decorations, and UI elements.
AI Generation Prompt
Free CSS Pseudo-Element Generator
Overview
This application is a dedicated, visual-first utility for generating CSS code for :before and :after pseudo-elements. It enables users to style decorative elements without modifying the underlying HTML structure, fostering clean and maintainable codebases.
Technical Directives
- Architecture: Must be a single, standalone HTML file containing all logic (CSS/JS).
- Sandbox Compatibility: Do NOT use
localStorage,sessionStorage,cookies, or any persistent storage. Use JavaScript state objects for real-time updates. Do NOT usealert(),confirm(), orprompt(). All notifications must be custom HTML modals. - Dependencies: Tailwind CSS via CDN is permitted for rapid, responsive UI development. Font Awesome CDN is permitted for iconography.
- Design: Strict Light Mode only. Use a professional, SaaS-inspired aesthetic with high contrast, crisp borders, and subtle shadow effects.
Feature List
- Visual Preview Pane: A central canvas showing a live representation of the element's parent container and its pseudo-elements.
- Property Control Panel: A side-aligned panel featuring inputs for:
- Content (text or empty strings)
- Positioning (Absolute, Relative, Fixed)
- Dimensions (Width, Height)
- Background (Colors, Gradients)
- Borders (Radius, Width, Style, Color)
- Transform (Rotation, Scale, Skew)
- z-index management
- Real-Time Code Generator: A code block at the bottom of the screen that updates instantly as inputs change.
- One-Click Copy: A prominent button to copy the generated CSS directly to the clipboard with visual success feedback.
UI Layout
- Header: Simple, clean title ("Pseudo-Element Generator").
- Main Tool Area:
- Left Sidebar: Controls organized into logical sections (Layout, Appearance, Transform).
- Center Preview: A large, isolated box showcasing the parent and the :before/:after elements.
- Bottom Bar: A dedicated section displaying the CSS output in a code-friendly font (e.g., Fira Code or Monospace).
Aesthetics & Styling
- Color Palette: Slate-900 for text, White background for surfaces, Gray-50 for backgrounds, Indigo-600 for primary action buttons.
- Animations: Subtle transitions (
transition: all 0.2s ease-in-out) on all inputs to provide a high-quality feel. When clicking "Copy", trigger a temporary "Copied!" toast notification. - Responsiveness: Single-column layout on mobile (stacked), moving to a side-by-side split layout on tablet and desktop.
Constraints Checklist for Developer
- No branding names or logos.
- No dark mode toggle.
- No local storage interaction.
- No third-party tracking/analytics (unless strictly necessary via CDN).
- Fully responsive CSS grid/flexbox layout.
- All code encapsulated in one file.
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Files being used
Frequently Asked Questions
Everything you need to know about using this application.
What is the purpose of this CSS Pseudo-Element Generator?
This tool is designed to help web developers and designers rapidly create and visualize CSS :before and :after pseudo-elements. By providing a graphical interface for properties like content, positioning, sizing, and styling, it eliminates the need to manually write and test boilerplate CSS code in a separate editor. The generator creates production-ready CSS snippets that you can copy and paste directly into your stylesheet. It is particularly useful for creating decorative shapes, icons, and complex UI layouts without adding extra HTML tags to your document structure.
Does this tool store my generated CSS code?
No, this application is completely stateless. Due to strict security and privacy standards for sandboxed web environments, this tool does not use localStorage, cookies, or any database to save your work. Your data stays entirely in your browser's volatile memory and is cleared as soon as you refresh the page. Because of this, we recommend copying your generated code immediately after you finish your design. This approach ensures maximum privacy and security, as no user data is ever transmitted to a server or persisted on your machine.
Is the generated CSS code compatible with all browsers?
The generated CSS code utilizes standard, modern CSS properties that are widely supported across all major browsers, including Chrome, Firefox, Safari, and Edge. The tool focuses on standard :before and :after pseudo-selector syntax that has been part of the CSS specification for many years. For advanced shapes using properties like clip-path or complex gradients, we provide clean, standard-compliant code. You can use this code in any web project with confidence that it will render consistently across modern devices and platforms.
Can I use this for complex shape animations?
While this tool is primarily a generator for static pseudo-element styles, it provides a solid foundation for your animations. You can generate the base CSS for your :before or :after element, then add your CSS keyframe animations to the code in your own development environment. The visual builder helps you perfect the dimensions, colors, and positioning of your element, which is the most time-consuming part of the process. Once you have the perfect base, you can easily extend it with transitions or animations within your project's stylesheet.
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