The one source of truth for every value that can change.

A systematic approach to color with purpose, contrast, and accessibility.

Type as a system: families, a scale, a measure — and the most popular fonts in the world.

Consistent rhythm through a systematic spacing scale.

The five-level hierarchy that structures design systems.

Structured layouts with consistent alignment, spacing and containers.

Depth, shadows, and z-index strategy.

A coherent icon system: grid, style, sizing, and accessibility.

Tables, lists and data density.

Data visualisation as a set of components, not a pile of one-off drawings.

Statistical graphics for exploration and communication: box, violin, histogram, density, Q-Q, and correlation heatmap.

Toasts, alerts and banners.

Accessible, usable forms that guide users to success.

Headers, sidebars, tabs, breadcrumbs and more.

Modals, drawers, popovers, menus and tooltips.

Motion as a system: tokens, choreography, and accessibility.

Target WCAG 2.2 AA, and make the accessible path the default path.

Design for the range of screens, not for a list of devices.

One system, multiple themes.

How a design system ships, evolves and stays adopted.

Thirty named principles from psychology that explain why an interface feels obvious — and where it breaks.

Perceptual uniformity, gamut mapping, and colour-blind safety.

Props, variants, slots, and polymorphism — the interface between system and consumer.

Virtualization, resizing, editing, sticky, density — the hard parts of tables.

Logical properties, mirrored icons, bidi text, and locale-aware formatting.