Line Chart Card

name: "Line Chart Card"
short_description: A line-chart widget with a headline value, period toggle, and a filled trend line.
long_visual_description: >
  A widget card with a title and headline value, a period toggle (7D/30D/90D), and a line
  chart with a soft area fill and optional x-axis labels.

use_cases:
  - Revenue or growth trend over time.
  - Time-series metric on a dashboard.
  - Traffic or usage line chart.
  - Any single-series trend widget.
  - KPI with a period selector.

recommended_for:
  - A single-series time trend with a period selector.
avoid_for:
  - Categorical comparison (use chart-card-bar).

markets:
  - Global

example_usage: >
  Precompute the polyline points on a 300×120 viewBox; provide period toggles and optional
  x-axis labels. Swap the points when the period changes.

props:
  title: The chart title.
  value: The headline value.
  periods: The period toggles (one active).
  points: Precomputed SVG polyline points.
  x_labels: Optional x-axis labels.

example_prompts:
  - "Add a revenue line chart card with a 7D/30D/90D toggle."
  - "Add a time-series line widget with a headline value."

lifecycle: experimental
content_model: A titled line-chart widget with a period selector.

theming:
  tokens_used:
    - --color-surface
    - --color-on-surface
    - --color-on-surface-muted
    - --color-border
    - --color-primary
    - --color-primary-contrast
    - --radius-card
    - --radius-control
    - --shadow-card
    - --font-heading
    - --space-card
    - --duration-token

editorial_guidance: >
  Keep the headline value in sync with the active period; the chart is illustrative of the trend.

categorization:
  category: Dashboard
  subcategory: Charts
  atomic_type: organism
  usage_type: [stat, card]
  maturity: ai-generated
  wcag:
    level: AA
    notes: The chart is decorative (aria-hidden); the title, value, and period toggles are real text/controls. Provide a data table alternative for non-visual users in production.
  keyboard_support: Period toggle buttons are focusable and activate on Enter/Space.
  seo_score: 30
  text_direction: both