Lily Design System™

Grail Layout Center Main

GrailLayoutCenterMain is a headless container for the center main content section of a GrailLayout. It holds the primary page content and is flanked by the left and right aside sections.

Example

Main content
Show demo markup 
<main class="grail-layout-center-main">Main content</main>
Usage example 
<script lang="ts">
    import GrailLayoutCenterMain from "./GrailLayoutCenterMain.svelte";
</script>

<GrailLayoutCenterMain>
    <main>
        <h1>Welcome</h1>
        <p>This is the primary content.</p>
    </main>
</GrailLayoutCenterMain>
Show Svelte source 
// In your Svelte component:
import GrailLayoutCenterMain from "lily-design-system-svelte-headless/components/GrailLayoutCenterMain/GrailLayoutCenterMain.svelte";

<GrailLayoutCenterMain>
  <!-- content -->
</GrailLayoutCenterMain>

Usage

<GrailLayout>
  <GrailLayoutTopHeader>...</GrailLayoutTopHeader>
  <GrailLayoutLeftAside>...</GrailLayoutLeftAside>
  <GrailLayoutCenterMain>
    <h1>Patient Dashboard</h1>
    <p>Main content area with patient records, charts, and clinical notes.</p>
  </GrailLayoutCenterMain>
  <GrailLayoutRightAside>...</GrailLayoutRightAside>
  <GrailLayoutBottomFooter>...</GrailLayoutBottomFooter>
</GrailLayout>

Props

  • children: slot (required) -- content to render inside the center main section
  • ...restProps: unknown -- additional attributes spread onto the <div> element

When to Use

  • Use inside GrailLayout as the primary content area.
  • Use to hold the main page content that is flanked by the left and right aside sections.
  • Use for the central focus of the page such as patient records, dashboards, or article content.

When Not to Use

  • Do not use outside GrailLayout -- use a <main> element directly.
  • Do not use for sidebar content -- use GrailLayoutLeftAside or GrailLayoutRightAside instead.

Keyboard Interactions

  • No keyboard interactions — this is a passive landmark container
  • Focusable descendants follow native tab order

ARIA

  • Native <main> exposes a main landmark; there should be only one per page
  • Implicit main role from the <main> element when used as a top-level landmark

Headless

This headless component renders semantic HTML. The consumer provides all visual styling — no CSS, animations, or layout assumptions are baked in.

Styles

The consumer provides all CSS styling. The component renders with a .grail-layout-center-main class for targeting. No default styles are included — this is a fully headless component.

Testing

  • Verify the component renders a <main> element with class grail-layout-center-main
  • Verify pass-through attributes are applied

Composition

GrailLayoutCenterMain is used as a child of GrailLayout. Place a semantic <main> element inside for proper accessibility.

Related components

  • grail-layout — a responsive web design structure with header, left aside, center main, right aside, footer
  • grail-layout-bottom-footer — grail layout bottom footer full width with <footer> tag
  • grail-layout-left-aside — grail layout left aside sidebar with <aside> tag
  • grail-layout-right-aside — grail layout right aside sidebar with <aside> tag
  • grail-layout-top-header — grail layout top header full width with <header> tag

References

  • CSS Grid Layout: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_grid_layout

Implementation Notes

  • Renders a <main> element for the center main content section
  • Spreads restProps onto the div for consumer customization
  • No styles applied; consumer provides all styling

Canonical contract

Generated from this component's canonical metadata — the machine-checked source the implementations are held to.

Metadata

  • Component: grail-layout-center-main
  • PascalCase: GrailLayoutCenterMain
  • Description: grail layout center main content with <main> tag
  • Status: beta — implemented and unit-tested in all seven frameworks with an axe-clean demo page; not yet exercised in composed flows
  • HTML tag: <main>
  • CSS class: .grail-layout-center-main
  • Interactive: no

ARIA

  • Native <main> element exposes the main landmark
  • Only one <main> should be present per page

Keyboard

  • No keyboard interactions — this is a passive element

Props

  • children: slot (required) -- content to render inside the center main section
  • ...restProps: unknown -- additional attributes spread onto the <div> element

### Grail layout pattern: GrailLayout → GrailLayoutTop, GrailLayoutLeft, GrailLayoutCenter, GrailLayoutRight, GrailLayoutBottom

```tsx

<GrailLayout>

<GrailLayoutTopHeader>…</GrailLayoutTopHeader>

<GrailLayoutLeftAside>…</GrailLayoutLeftAside>

<GrailLayoutCenterMain>…</GrailLayoutCenterMain>

<GrailLayoutRightAside>…</GrailLayoutRightAside>

<GrailLayoutBottomFooter>…</GrailLayoutBottomFooter>

</GrailLayout>

```