For AI agents: the complete documentation index is available at https://a3s-lab.github.io/UI/v0.4.1/en/llms.txt, the full documentation bundle is available at https://a3s-lab.github.io/UI/v0.4.1/en/llms-full.txt, and this page is available as Markdown at https://a3s-lab.github.io/UI/v0.4.1/en/index.md.

Complex UI.Clear grammar.

A3S task patterns for app shells, ribbons, split panes, and state models, delivered as semantic HTML with React and Vue adapters plus small vanilla JavaScript controllers.

$npm install @a3s-lab/ui@0.4.1
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Component contracts
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Design foundations
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Framework runtimes
PUBLIC COMPONENT COMPOSITIONINTERACTIVE A3S OFFICE WORKBENCH
A3S Office Saved
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Font
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Insert
WORKSPACE / RECENT

Continue where you left off

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From one control to a complete workspace.

General components are grouped by interface responsibility. Structured forms and Harness use the same component navigation, visual language, and state contracts. Every guide includes a live specimen.

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Tune A3S UI to your product.

Choose appearance, accent, radius, and interface density. Changes apply to the entire site and every component preview immediately, then persist for your next visit.

Appearance
Accent
Radius
Density
Semantic HTML
Browser-native behavior
Form and Harness
Responsive + RTL
Server templates

One semantic contract. Multiple visual foundations.

Color, type, and shape can change while component structure, interaction state, and accessible behavior stay intact.

ACTIONSUCCESSAGENTATTENTIONDANGER
TYPE SCALEAa

Geist Sans

12 / 14 / 16 / 20 / 32 / 64
SPACING SCALE4812162432
CONTROL SHAPER06 / R10 / R14

Three non-negotiables.

Use the platform

Native controls and semantic landmarks come first. JavaScript appears only when the browser does not supply the interaction.

Keep one contract

CSS variables and documented data attributes adapt the interface without forking structure or accessibility behavior.

Design for dense work

Compact chrome, predictable focus, and responsive workspaces keep complex product surfaces legible.

Start with a real interface.

Install @a3s-lab/ui, choose a visual foundation, then copy working markup from App Shell, Form, Harness, or any component contract.

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