ANTJANUS

antjanus.com/patterns.html
Antonin Januska · Boulder, Colorado

Pattern library · /patterns

UI Patterns

A UI pattern library built for coding agents. 40 patterns, each shipping a copy-paste prompt that rebuilds it inside your own codebase — plus a live preview and the source behind it.

A blueprint drawing of interface parts: dialled gauges, dimensioned panels, and a grid of repeated tiles
patterns-hero-1.webp

Every pattern, three ways

1. Preview
The pattern running live in an isolated frame, in whichever theme you are reading in.
2. Source
Its markup, styles and behaviour, plus a single runnable file carrying its own palette.
3. Prompt
A written spec that rebuilds the pattern from scratch — including why each decision is the way it is. Paste it into Claude Code, Cursor, or any coding agent.

The prompts are the point. Each one is written to survive being handed to an agent with no other context: it names the surfaces the pattern belongs on, spells out the constraint that makes it work, and calls out the failure it exists to prevent. Nothing here is a dependency you install.

All patterns

40 patterns

Category
  • Added 2026-08-11

    Windowed schedule grid

    Rows of resources against a fixed time window, where each block is sized by its overlap with the window rather than by its own duration.

    • schedule
    • timeline
    • grid
    • flexbox
    • time
  • Added 2026-08-11

    Benchmark progress bar

    Places a raw figure on a scale of external benchmarks instead of printing it plain.

    • progress
    • benchmarks
    • css-only
    • data-viz
    • empty-state
  • Added 2026-08-11

    Cross-highlight matrix

    A two-axis lookup table with both headers sticky, hover lighting the full row and column at once, and a durable click-to-pin selection for touch.

    • table
    • matrix
    • sticky
    • accessibility
    • hover
  • Added 2026-08-11

    Left-truncating paths

    Shortens a long path by dropping whole segments from the left, because the tail is what tells two paths apart.

    • truncation
    • paths
    • text-overflow
    • breadcrumbs
    • file-systems
  • Updated 2026-08-21 Updated

    Shape-mark sequence

    A sequence compressed into a row of small marks whose shape carries the state.

    • stepper
    • sparkline
    • series
    • truncation
    • css-only
    • no-assets
  • Added 2026-08-21

    Linked month bars

    A month-by-month volume timeline built from plain divs where every aggregate row links to the filtered view that produced it.

    • timeline
    • drill-down
    • css-only
    • data-viz
    • no-assets
  • Added 2026-08-21

    Glass vial meter

    A vertical potion-vial meter whose liquid fills a wide bulb first and then rises into a narrow neck — all CSS, no images.

    • meter
    • skeuomorphic
    • css-only
    • reduced-motion
    • no-assets
  • Added 2026-09-12

    Partitioned stage bar

    Progress for work with several possible endings, drawn as a census rather than a fraction.

    • progress
    • stacked-bar
    • batch
    • legend
    • status
    • aria-label
  • Added 2026-09-12

    Term-by-term derivation

    A computed figure shown with the audit trail behind it — the number is the product and the derivation is the receipt.

    • explainability
    • calculator
    • disclosure
    • formula
    • tabular-nums
    • details
  • Updated 2026-09-12 Updated

    Plan preview tree

    A dry run shown as a before-and-after tree with counts now, after, and the difference.

    • dry-run
    • diff
    • tree
    • preview
    • bulk-operation
    • confirmation
  • Added 2026-09-12

    Uniform slot shell

    One card shell many independent sources render through, where the shell does the capping.

    • dashboard
    • widgets
    • cards
    • empty-state
    • error-state
    • grid
  • Updated 2026-08-11 Updated

    Object-shaped cards

    Where a record stands for a physical thing, the card is drawn as that thing — nine variations in pure gradients.

    • cards
    • css-only
    • gradients
    • variations
    • no-assets
    • skeuomorphic
  • Added 2026-08-11

    Adaptive tile mosaic

    A container with no artwork draws one from up to four member tiles, grid tracks following tile count.

    • css-grid
    • css-only
    • no-assets
    • cards
    • layout
  • Updated 2026-08-11 Updated

    Ground-scrimmed artwork

    Text printed over unreviewed artwork, scrimmed to an alpha that can be written down rather than guessed.

    • layout
    • css-only
    • gradients
    • contrast
    • no-assets
    • hero
    • cards
  • Updated 2026-08-21 Updated

    Hairline stat strip

    Stat tiles joined by hairlines that are grid gap, not borders.

    • stats
    • css-grid
    • css-only
    • hairline
    • no-assets
  • Added 2026-08-21

    Annotated transcript

    Conversation bubbles with a speaker-colored spine and a fixed metadata gutter.

    • conversation
    • gutter
    • status-roles
    • contrast
    • css-only
  • Added 2026-08-21

    Cork notice board

    Pinned paper notes on a cork board where every texture is layered CSS gradients.

    • skeuomorphic
    • gradients
    • no-assets
    • cards
    • css-only
  • Updated 2026-09-12 Updated

    Hotspot marker layer

    Markers at percentage coordinates over a fixed-aspect picture, turning into a list when too narrow.

    • hotspots
    • pointer-events
    • aspect-ratio
    • container-query
    • overlay
    • responsive
  • Added 2026-09-12

    Line-art empty states

    Inline drawings for empty surfaces stroked in the inherited text colour.

    • empty-state
    • svg
    • currentcolor
    • illustration
    • aria-hidden
    • no-assets
  • Added 2026-09-12

    Column-flow wall

    Cards flowing down columns instead of across rows, with the reading-order cost stated plainly.

    • masonry
    • columns
    • break-inside
    • reading-order
    • cards
    • responsive
  • Added 2026-08-11

    Scroll edge shadows

    An inset shadow shown only on the edge that has more content behind it.

    • scrolling
    • affordance
    • lists
    • overflow
    • progressive-disclosure
  • Added 2026-08-11

    Frozen-batch deck

    A one-card-at-a-time review queue whose batch is snapshotted at mount.

    • queue
    • review-flow
    • animation
    • keyboard
    • reduced-motion
  • Updated 2026-08-11 Updated

    Controls beside the anchor

    Per-card controls over a fully-linked card without nesting interactive elements in the anchor.

    • cards
    • accessibility
    • keyboard
    • focus-within
    • grid
  • Updated 2026-08-11 Updated

    Pluggable canvas visualizer

    One canvas, a registry of draw modes, each mode owning its entire frame.

    • canvas
    • visualization
    • registry
    • animation
    • reduced-motion
  • Updated 2026-08-21 Updated

    Roving-grid board

    A dense grid of state cells that is one tab stop with arrow-key navigation.

    • keyboard
    • roving-tabindex
    • accessibility
    • states
    • dense-data
  • Added 2026-08-21

    Section rail

    Sticky vertical rail on wide screens, wrapping tab row on narrow ones, from the same markup.

    • navigation
    • toc
    • responsive
    • aria-current
    • intersection-observer
    • container-queries
    • sticky
  • Added 2026-08-21

    Ledge-press buttons

    Buttons on a solid ledge shadow that travel down onto it when pressed.

    • buttons
    • skeuomorphic
    • press
    • tokens
    • css-only
  • Updated 2026-09-12 Updated

    Guarded control

    A blocked control stays focusable, carries the reason as text, and refuses in its handler.

    • aria-disabled
    • disabled
    • preconditions
    • keyboard
    • aria-describedby
    • forms
  • Updated 2026-09-12 Updated

    Polled job card

    One card for every state a background job passes through.

    • progress
    • polling
    • background-job
    • indeterminate
    • aria-busy
    • reduced-motion
  • Added 2026-09-12

    Entry-transform motion

    FLIP-style motion between two rendered states when the old DOM is already gone.

    • animation
    • transitions
    • reflow
    • reduced-motion
    • navigation
    • layout-effect
  • Updated 2026-09-12 Updated

    Slot-first picker

    Assignment that starts at the destination slot, then narrows the catalogue.

    • assignment
    • picker
    • aria-pressed
    • filtering
    • forms
    • data-driven
  • Added 2026-08-28

    Undo toast

    A destructive action with no confirm dialog, held behind a toast and committed when it expires.

    • undo
    • toast
    • destructive
    • aria-live
    • reduced-motion
  • Added 2026-09-28 New

    Blast-radius confirm

    A confirm dialog that names everything a delete cascades and blocks dismissal while it runs.

    • confirm-dialog
    • destructive
    • cascade
    • dialog-element
    • forms
  • Updated 2026-08-28 Updated

    Batch action bar

    A bar that exists only while something is selected, states the count in words, caps at five actions.

    • selection
    • bulk-actions
    • toolbar
    • checkbox
    • indeterminate
    • bulk-edit
    • mixed-values
  • Added 2026-09-12

    Filtered to zero

    The three empty states a list actually has, written as three different screens.

    • empty-state
    • filter
    • search
    • zero-results
    • aria-live
    • copywriting
  • Added 2026-09-12

    Parsed query chips

    A search box that echoes back how it read the text as removable chips.

    • search
    • query-syntax
    • chips
    • facets
    • parsing
    • aria-live
  • Added 2026-09-12

    Compound-value picker

    One grouped select whose value carries both the kind and the id.

    • select
    • optgroup
    • polymorphic
    • forms
    • dependent-fields
    • keyboard
  • Updated 2026-08-11 Updated

    Ground-referenced color

    Colors solved against the page's own ground token so they invert correctly between themes.

    • color
    • contrast
    • color-mix
    • accessibility
    • wcag
    • theming
    • year-map
  • Updated 2026-08-21 Updated

    Single-property color variants

    One custom property carries the hue; border, fill, spine and dot derive from it.

    • color
    • color-mix
    • custom-properties
    • theming
    • data-attributes
    • badges
  • Updated 2026-09-12 Updated

    Controls on an unknown fill

    Opaque controls, a gradient-darkened fill, and a two-tone focus ring on a surface whose colour arrives from outside.

    • contrast
    • brand-color
    • focus-ring
    • opacity
    • wcag
    • theming