Open-source alternatives to BOOTSTRA.386

MUI is a lightweight CSS framework that implements Material Design visual and interaction guidelines for web interfaces. It provides a suite of tools for building interfaces through a responsive CSS grid system and a set of components based on standardized visual patterns. The library includes a customizable CSS theme engine and a specialized HTML email styling library. These tools allow for the modification of default palettes and visual styles to align an interface with a specific brand identity, while ensuring consistent rendering of email templates across different email clients. The fra

pickadate.js is a responsive jQuery date and time picker designed for web forms. It provides a localized input interface that allows users to select specific calendar dates and precise clock times. The library features a customizable calendar UI with configurable colors, sizes, and breakpoints. It includes a localization system to adapt interface text and date formats into multiple languages and regional settings. The component includes interactive date and time inputs and a styling system for modifying visual design to match specific brand identities. Its layout automatically adjusts for di

Framework7 is a mobile user interface framework and single-page application system designed to build responsive web applications with native iOS and Android appearances. It provides a comprehensive library of pre-styled components and a layout engine to create native-style user interfaces across multiple platforms. The framework utilizes a platform-aware theming system that adapts visual styles and color schemes based on detected device settings. It incorporates native mobile behaviors through a dedicated UI kit, including specialized interaction patterns such as pull-to-refresh and swipeable

This project is a minimalist visual theme and customizable CSS framework for Obsidian. It functions as a markdown layout engine and an adaptive user interface designed to remove interface clutter and create a distraction-free writing environment. The theme distinguishes itself through layout transformations that convert standard markdown tables and lists into card-based grids and visual galleries. It provides a system for transforming structured data into scannable visual representations and organizes consecutive images into column-based grids. The framework covers comprehensive interface ae

98.css is a CSS retro UI framework and component library designed to recreate the visual aesthetic of legacy desktop operating systems. It serves as a retro design system and web UI emulator, providing a collection of styles to build faithful reproductions of vintage user interfaces. The framework employs a CSS-only component architecture to emulate classic software environments. It uses border-shadow emulation and state-based visual transitions to simulate physical button presses and three-dimensional panels without requiring external JavaScript logic. The library covers a wide range of int

Materialize is a Material Design CSS framework and component library. It provides a collection of reusable visual elements and styles used to build web page designs that follow the Material Design specification. The project includes a responsive web layout engine to create adaptive user interfaces. This system automatically adjusts structure and spacing based on screen size to ensure consistency across different devices. The framework covers frontend UI prototyping and general CSS integration, utilizing a grid system and pre-styled components to assemble functional website layouts.

NES.css is an 8-bit CSS framework and styling system that transforms standard HTML elements into pixelated interfaces inspired by classic gaming consoles. It serves as a retro UI component library and toolkit for rendering text, borders, and icons with a blocky aesthetic. The framework uses pure CSS to emulate 8-bit graphics without relying on external images or JavaScript rendering. It implements pixel-art border simulations and integrates pixel-style web fonts to maintain a consistent gaming aesthetic across different browsers. The system provides a suite of game-themed interface elements,

new.css is a classless CSS framework that styles semantic HTML elements automatically. It provides a modern visual design for websites by applying rules directly to standard HTML tags, removing the requirement for manual class name assignments. The project includes a CSS theme engine and predefined aesthetic skins, such as a high-contrast dark mode and a terminal-style interface featuring monospace typefaces and command-line color schemes. These visual identities are managed through CSS variables, allowing for palette customization and theme switching. The framework covers a range of visual

This project is a comprehensive technical reference for web favicon specifications, providing the image dimensions and file formats required for browser and operating system icons. It serves as a platform icon configuration sheet for mobile touch icons and desktop home screen tiles. The guide includes specialized instructions for implementing theme-aware icons using SVG media queries to support light and dark mode appearances. It also provides a reference for managing browser icon caches to force updates during development and production. The reference is delivered as a static site generated

React95 is a React UI component library and themed framework designed to emulate the aesthetic of a nineties desktop operating system. It provides a collection of reusable interface elements that allow developers to build web applications with a nostalgic visual style. The library functions as a design system centered on a Windows 95 theme. It utilizes a centralized theme provider to manage global color palettes and styling across the application. The framework covers retro UI development through a set of pre-styled components and themed interface design tools. These capabilities enable the

Papercss is a CSS UI framework and document-style design system used to build responsive web page layouts. It functions as a Less-based CSS library that applies a paper-like aesthetic and structured typography to give web pages the appearance of physical documents. The project also incorporates a utility-first CSS library model for rapid styling. The framework is distinguished by its ability to automate visual decorations, such as applying rotating border styles and shadow effects to child elements. It utilizes a Less-based variable system and modular stylesheet compilation, allowing users to

Nord is a cross-platform design palette and CSS color system providing a curated set of dimmed pastel colors for building consistent user interfaces and code themes. It functions as a UI design framework that delivers a standardized collection of colors through multiple file formats for use in development tools and graphic design software. The system is defined by its dual-mode visual theme, which coordinates complementary light and dark color sets to maintain a consistent visual hierarchy across different brightness modes. It also includes a syntax highlighting theme that maps specific palet

Foundation Sites is a responsive front-end framework providing a collection of CSS and JavaScript tools to build websites that automatically adapt to different screen sizes and devices. It functions as a responsive design library and cross-browser UI toolkit, offering a grid layout system and pre-styled interface components to ensure consistent rendering across modern web browsers. The framework enables rapid front-end UI prototyping and the integration of interactive components through a scripting interface that manages the lifecycle of UI plugins. It supports custom CSS framework management

system.css is a CSS component library and design system used to build web applications that mimic the look and feel of traditional desktop computing environments. It provides a toolkit of semantic classes and global variables to ensure visual uniformity across nostalgic, retro-inspired user interfaces. The framework enables the development of desktop-style web applications by structuring content within window containers and modal dialogs. It specifically supports the creation of monochrome interfaces and layouts that replicate the aesthetic of classic Macintosh operating systems. The library

Skeleton is a lightweight responsive CSS boilerplate and mobile-first framework. It provides a foundation for building mobile-friendly websites through a fluid 12-column grid system, a minimal CSS reset library to normalize browser defaults, and default styling for raw HTML elements. The project emphasizes a mobile-first development approach, using percentage-based widths and predefined media queries to progressively enhance layouts for larger screens. It includes a utility-first library of single-purpose classes to manage common layout tasks such as floating elements, clearing, and width con

UIkit is a CSS front-end framework and accessible UI component library designed for building responsive web interfaces. It provides a comprehensive set of styling classes and modular components alongside a JavaScript interaction toolkit for managing behavioral elements. The framework includes native support for internationalized web interfaces, featuring multi-locale text translation and right-to-left layout directions. It employs a responsive layout engine that uses flexible grids, adaptive breakpoints, and container widths to align content across different screen sizes. The toolkit covers

Susy is a Sass layout framework and grid computation engine designed to automate complex mathematical layout calculations within stylesheets. It functions as a responsive grid generator that calculates column widths, gutters, and spans based on customizable viewport breakpoints to ensure precise element alignment. The system includes a visual layout debugger that generates browser-based grid overlays to verify column alignment and baseline rhythm during development. It also provides utilities for creating repeating background colors and gradients using a template-based syntax. The framework

Pure is a CSS UI framework and modular component library designed for building consistent web layouts and interface components. It functions as a responsive CSS grid system and a CSS reset library that normalizes default browser rendering to ensure a uniform appearance across different web environments. The project provides standalone styles for common interactive elements such as buttons, menus, forms, and tables. It utilizes a modular architecture that allows for the inclusion of specific style modules and employs namespace isolation to prevent visual conflicts between components. The fram

Rebass is a React design system library that provides a collection of theme-driven, responsive UI primitives. It functions as a theme-based layout engine, using a set of stateless components to standardize spacing, typography, and colors across a user interface. The library distinguishes itself by mapping style properties to a central design theme through a styled-system approach. This allows for responsive style mapping where components automatically adapt their appearance based on screen size and provides the ability to swap underlying HTML elements while preserving styling logic to maintai

HyperUI is a dependency-free collection of responsive HTML layouts and pre-styled components designed for various web domains. It functions as a Tailwind CSS component library where users integrate standalone HTML snippets via a copy-paste distribution model to avoid package installation and framework overhead. The library features one-click markup copying from a pre-built component gallery. It includes specialized design systems, such as high-contrast neobrutalist styling with heavy borders, and visual tools for generating dark mode color palettes and harmonic typography scales. The compone

Semantic-UI is an HTML and CSS UI framework consisting of a themed component library and a responsive layout framework. It provides a collection of reusable interface components and a grid-based system of columns and containers designed to build responsive websites. The framework is distinguished by its use of natural-language class naming, which maps human-readable CSS classes to specific visual styles. It also functions as a right-to-left UI toolkit, utilizing directional mirroring to adjust visual flow and element alignment for languages read from right to left. The system covers frontend

Tachyons is a utility-first CSS framework and functional CSS library. It provides a collection of single-purpose classes used to style elements and build layouts without writing custom CSS. The framework centers on a mobile-first responsive design system and a nestable grid architecture that adapts layouts across different screen sizes. It includes accessible color palettes and schemes designed to meet visual contrast and accessibility standards. The system provides tools for utility-first styling, responsive layout management, and visual debugging to resolve alignment and spacing issues.

Bootstrap-vue is a Vue.js component library and responsive UI kit based on the Bootstrap CSS framework. It provides a frontend component suite of reusable interface elements designed for building mobile-first websites and web applications. The project wraps Bootstrap CSS classes in Vue components to manage styles and behaviors through reactive state. It integrates a responsive layout management system that synchronizes internal component states with Bootstrap's grid system and device breakpoints. The library covers a wide range of interface capabilities, including data display with sortable

StyleX is a type-safe CSS-in-JS library and atomic CSS compiler that transforms JavaScript style definitions into optimized static CSS and type-safe class names. It functions as a multi-framework styling tool, generating standard CSS assets compatible with various JavaScript UI frameworks and server components. The system includes a CSS design token system and theme engine for managing shared constants and composing visual schemes. It allows for the creation of light, dark, and custom themes through variable overrides and token inheritance. The project covers component styling through object

Fomantic-UI is a component-based CSS library and frontend design system used to build consistent, responsive user interfaces. It functions as a CSS framework and responsive UI toolkit, providing a structured approach to managing typography, color palettes, and spacing. The project enables the development of custom UI components and the implementation of unified design systems across web applications. It provides a variable-driven theme compilation process to customize visual styles and a build-time system to compile selected components into production CSS bundles. The toolkit covers a broad

The mdb-ui-kit is a frontend component library and visual extension that combines the Bootstrap 5 framework with Material Design principles. It provides a collection of pre-styled interface elements and responsive web templates to facilitate the development of consistent web applications. The toolkit extends the Bootstrap ecosystem by adding Material Design aesthetics and advanced styling options. It enables rapid prototyping through the use of pre-configured design blocks and provides mechanisms for deep visual customization via SCSS variables and native CSS custom properties, including supp

ring-ui is a web UI component library used to build consistent web applications through a shared set of reusable interface elements and standardized styles. It provides a foundation for web interface development, specifically supporting the creation of visual experiences for software extensions and plugins. The library includes a grid-based layout system for organizing screen content and maintaining responsiveness across different window sizes. It features a CSS variable theming system for applying consistent visual identities, a data table framework for rendering large datasets, and a form i