Definition
Bulma is an open-source CSS framework based on Flexbox that provides ready-made classes for layout, typography, and common UI components, with no JavaScript included.
Overview
Bulma provides a set of CSS classes for building responsive layouts and interfaces — grids, columns, navbars, cards, forms, and buttons — built entirely on Flexbox. Unlike frameworks such as Bootstrap that ship with bundled JavaScript for interactive components, Bulma is CSS-only: any interactivity (opening a modal, toggling a menu) has to be implemented separately by the developer, giving more control at the cost of needing extra code for behavior. Its class-naming approach favors readable, modifier-based names (`button is-primary is-large`) that describe intent directly in the markup, which many developers find approachable when first learning to build responsive layouts without deep custom CSS or a JavaScript-heavy component library. Bulma is commonly compared to other utility- or component-based CSS frameworks like DaisyUI (built on Tailwind) or Foundation CSS; teams choose it when they want a lightweight, semantic-class CSS framework without committing to a JavaScript component library or a utility-first workflow.
Key Features
- Pure CSS framework with no JavaScript dependencies
- Flexbox-based responsive grid and column system
- Modifier-class naming convention (is-primary, is-large) for readable markup
- Pre-styled components for navbars, cards, forms, and buttons
- Sass-based source files for deep customization of variables and themes
- Framework-agnostic — usable with plain HTML or any JavaScript framework