c2n/web-componentsv1.0.18
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OverviewGetting startedComponentsIconsGuidesExamples
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Butterfly chart

Two series back to back on a shared category axis, the categories named between them. The population pyramid is the classic case.

A butterfly chart compares two series category by category. label-field names each row, and the two c2-chart-series grow away from each other from a gutter in the middle, where the categories are written: the first towards the start, the second towards the end. A population pyramid (age bands, men against women) is the classic case; before and after, or two products’ scores on the same questions, read just as well.

Both sides share one scale, rounded to even steps, so equal values draw equal lengths. The start side’s axis is mirrored rather than negated: every value, tick and tooltip reads as the number it is. The tooltip lists both sides of a row, and the legend highlights a side (or, with legend-action="toggle", switches it off).

Import

import '@c2n/components/chart/butterfly-chart'

This chart draws with ECharts, a peer dependency it loads on first draw: npm install echarts.

Usage

Data and order

Rows are drawn top to bottom in data order: a population pyramid lists its oldest band first. Exactly two series are drawn; with one, the chart says it needs two, and any after the second are left out with a console warning.

Styling

--c2-chart__gutter--width (56px by default) is the space between the sides, where the categories are written: widen it for longer names. --c2-chart__bar--thickness (0.72) is the share of each row a bar fills, and the shared --c2-chart__bar--border-radius (0 to 0.5) rounds each bar’s value end, away from the gutter. The two sides take --c2-chart__series-1--color and --c2-chart__series-2--color.

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schema or your own markup.InputsJSON ViewerBrowse a JSON value as a collapsible tree, search it, and copy any path or value.Editors & viewersKanbanBoard layout and card movement by pointer or keyboard, with cards drawn by your own renderItem.PlanningKbdKeyboard key label for shortcuts and command hints, with the semantics of the native kbd element.Data displayKey Value EditorEditable KEY=value rows for environment variables and headers: paste a .env file to split it into rows, mask secret values, and flag duplicate or malformed keys.InputsLabelCaption that names and activates the control referenced by its for attribute, with a required marker.InputsLine chartA line chart over a time or numeric x axis, drawn on canvas by uPlot, with series declared as children.ChartLink ButtonText-styled control for link and navigation actions, rendered as a real anchor or a button.NavigationListVertical list container with single or multiple selection.Data displayList ItemSelectable row with icon 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mode.LayoutMaster DetailA list beside the record it opens, one pane at a time with a Back step when the element is narrow.LayoutMathTeX formulas rendered as native MathML: no font CSS, readable by screen readers, safe for untrusted input.Data displayMenuCommands, links, checkboxes and submenus in a popover anchored to a trigger.NavigationMenubarDesktop-style File, Edit and View menus in one bar, with the arrow-key and hover movement of an application menu bar.NavigationMermaidMermaid text diagrams drawn in your theme colours, loaded on demand and safe for untrusted sources.Data displayMeterA measurement inside a known range — storage, quota, strength — with native meter thresholds and an optional segmented breakdown.Data displayModalDialog built on the native dialog element: focus trap, backdrop, Escape, title, body and footer.FeedbackMoney InputCurrency amount field that groups digits as you type, follows the locale and stores an integer count of minor units.InputsMonth PickerPick a month, or a year: billing periods, reports and card expiry.InputsMonth PlannerMonth calendar that draws events and trips as bars across the days they cover.PlanningNavigation MenuSite navigation bar whose triggers open panels of links below the header.NavigationNotepadA rich-text notepad that looks like paper: handwriting on ruled lines, a formatting toolbar over the selection, checklists and tear-off pages.PlanningNotification CenterAn inbox panel of notifications grouped by day, with read and unread states and mark all as read.FeedbackNumber InputForm-associated numeric input with native validation, step controls, adornments and helper states.InputsOrg ChartA hierarchy drawn as connected cards that collapse and expand: an organization chart, a reporting line or a team structure.Data displayOTP InputForm-associated one-time-code field with one cell per character, paste and SMS autofill, grouping and masking.InputsOverflow ListOne row of actions or links that shows what fits and folds the rest into a "More" menu, refitting as its width changes.LayoutOverlap chartA Venn diagram of two or three sets, where each circle is a set and each shared area counts the members of exactly that combination.ChartOverlayAnchored popup built on the browser Popover API, positioned with floating-ui.FeedbackPage EditorA Notion-style editor for long text: Markdown shortcuts while you type, a / menu for blocks, a toolbar over selected text, code blocks with syntax colours and eight named colours.Editors & viewersPage HeaderThe top of a page: breadcrumb or parent link, your heading with status badges, description, metadata, page actions that fold into a menu, tabs and a toolbar.LayoutPaginationPage navigation in three layouts: numbered pages, a simple page status, or a table-footer row with rows-per-page.NavigationPassword FieldA password input with a show/hide toggle, a strength meter, a requirements checklist and a Caps Lock warning.InputsPhone InputA phone number field with a searchable 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service health, CI runs, host power.ChartStatus LightColoured dot plus a short label for the state of something, such as Live, Building or Failed.Data displayStatus PanelCommunicate empty states, operation outcomes and recoverable errors with clear next steps.FeedbackStepsThe trace of a task as it runs, or a stepper across the top of a view: statuses, durations, stages that open while they work, and steps the reader can select.Data displayStickyPins content to the top or bottom of its scroll container and tells you when it is stuck, optionally hiding it while the reader scrolls down.LayoutStreaming TextPlain text that arrives in bursts, such as an LLM answer, revealed at a steady pace behind a caret.ChatSwipe ActionA list row that slides sideways to reveal actions behind it, as in a mail or task list on a phone.LayoutSwitchOn/off toggle on a native switch input, with label, description and thumb icons.InputsTableVirtualized data grid with declarative columns, sorting, selection, pinning and resizing.Data displayTable Of ContentsAn "On this page" navigation that lists the headings of a document, nests them by level and highlights the section being read.NavigationTabsTab strip that shows one content panel at a time.NavigationTag InputTurns typed or pasted text into removable tags — recipients, keywords, labels — with configurable delimiters, parsing and validation.InputsText FieldSingle-line input with icon slots, clear button, helper and error text, and a character counter.InputsTextareaMultiline text input with resizing, helper and error text, and a character counter.InputsTheme SelectColour-theme switcher: click to step to the next mode, hover for the full menu.InputsTime InputForm-associated time-of-day input with a scroll-wheel picker, step and range constraints, helper text and error states.InputsTime Range PickerDashboard time range control: searchable quick ranges, an absolute range typed or picked on a calendar, time zone, shift and zoom, and auto-refresh.InputsTime Slot PickerPick a free time from someone's calendar: a row of days, then that day's times grouped into morning, afternoon and evening.InputsTimelineA vertical sequence of dated events on a connected rail: order history, activity feeds, changelogs.Data displayToastNotification cards and a manager for stacked, queued notifications with independent lifetimes.FeedbackTodo ListA to-do list with the feel of paper: hand-drawn ticks, notes, highlighters, swipe and drag, and a remembered look.PlanningToggletipA small ⓘ button that opens a help bubble on click or tap; the bubble can hold links and is announced to screen readers.FeedbackTooltipContextual hint shown when its target is hovered or focused, rendered in the top layer.FeedbackTourA guided product tour that spotlights one element at a time and explains it in a panel beside it.FeedbackTrace WaterfallShow the spans of a distributed trace as a tree, each with a duration bar on one shared time axis.Data displayTreeHierarchical tree view with expansion, selection, checkboxes and lazy loading.Data displayTree SelectA dropdown for picking one or several rows from a hierarchy, with checkboxes, search and a form value.InputsTreemap chartA whole split into nested rectangles, each sized by its value: market maps, budgets and disk usage.ChartTruncateClamps text to a number of lines, with an optional Show more button.Data displayUploadDrag-and-drop file selection with validation, upload progress, retry, cancellation, and attachment results.InputsView OptionsThe Display popover of a collection: layout, grouping, ordering on several levels, Show switches and visible properties, reported as one plain value.InputsVirtual ListWindowed list with built-in search, sorting, selection and an async data source.Data displayVisually HiddenText for screen readers only: kept in the accessibility tree, drawn nowhere, optionally shown while it holds focus.LayoutWaterfall chartA running total bridged by the steps that move it, where one row is one step and totals mark where the bridge lands.ChartWeek PlannerWeekly schedule with time blocks: a typical week with optional odd and even weeks, or a dated week the user edits.PlanningWorking IndicatorA live "work in progress" line: animated mark, shimmering label, trailing dots and elapsed time.FeedbackFeather Icons287 open-source Feather icons, one web component each.IconsMat Icon2,234 Material Icons ligatures rendered through a single element.IconsPhosphor Icons1,512 flexible icons in six weights, one web component each.IconsSymbols157 themeable spot illustrations for empty states, status panels, onboarding and error pages.IconsTask icons191 duotone icons for to-do items: work, home, health, sport, learning, food, money, travel and more.IconsThemingTheme every c2n component from a handful of design tokens with @c2n/theme, or reach for any component variable directly.GuideLanguagesComponents show their text in English; add your app’s languages as one JSON object, picked by the nearest lang.GuideFrameworksUse the components from React, Vue, Angular, Svelte, Lit or plain HTML — typed events, generated template types, and the one piece of configuration each framework needs.GuideUsing c2n in an applicationThe workflow behind every c2n app: load the theme once, use c2-* tags directly, and turn every repeated pattern into a small variant or composed component.GuideAI toolsGive Claude Code, Codex, Google Antigravity or GitHub Copilot the c2n skill, live component APIs, examples and application conventions.GuideNo components match.
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