/*
 * <x-pane>: a content region, with M3's margins and, optionally, a top app bar of its own.
 *
 * M3 puts all content in panes (docs/reference/m3/foundations.md § Layout → Scaffold, "all content
 * must live in a pane") and lets each carry its own app bar. The margin is the space between the
 * window's edge and what is inside: 16px below medium and 24px from it (600px), from the
 * per-breakpoint table in docs/reference/m3/foundations-supplement.md § Breakpoints, as
 * `--md-sys-measurement-space200` and `space300`.
 *
 * The margin sits on the pane's body and its section navigation, not on the pane: the app bar is a
 * direct child of the pane, so it spans the pane from edge to edge and its `position: sticky` holds
 * for the pane's whole height (a sticky element never leaves its parent). A margin is drawn once:
 * a region that already keeps its content off the window's edge — a pane's body, the canonical
 * layouts, the scaffold's content region — sets `--md-layout-margin` to 0px for what is inside it,
 * and a pane there draws none of its own, until an <x-surface> gives it a new edge to keep off.
 *
 * `data-md-width` caps the pane and centres it: `narrow` 40rem, M3's 40–60 characters a line
 * (§ Layout → Breakpoints, "keep text to 40–60 characters per line"), in rem because it is a measure
 * of text; `medium` 60rem and `wide` 80rem are the package's steps above it; `full` (the default)
 * fills the room it has, M3's flexible pane. The back button of `data-md-pane-back` points the
 * way it goes, so it mirrors in a right-to-left document (§ Layout → Bidirectionality / RTL).
 *
 * In `material.layout`; `hide-below`/`hide-from` come from visibility.css. Imports app-bar.css and
 * button.css for the pane's own top app bar and its back button (plan step 36 carry-over).
 */

@layer material.reset, material.tokens, material.base, material.layout, material.components, material.text, material.visibility;

@import './visibility.css';
@import '../components/app-bar.css';
@import '../components/button.css';

@layer material.layout {
    [data-md-pane] {
        display: flex;
        flex-direction: column;
        inline-size: 100%;
        min-inline-size: 0;
        margin-inline: auto;
    }

    [data-md-pane][data-md-width='narrow'] {
        max-inline-size: 40rem;
    }

    [data-md-pane][data-md-width='medium'] {
        max-inline-size: 60rem;
    }

    [data-md-pane][data-md-width='wide'] {
        max-inline-size: 80rem;
    }

    [data-md-pane-navigation],
    [data-md-pane-body] {
        padding-inline: var(--md-layout-margin, var(--md-sys-measurement-space200));

        @media (width >= 600px) {
            padding-inline: var(--md-layout-margin, var(--md-sys-measurement-space300));
        }
    }

    [data-md-pane-body] {
        flex: 1 1 auto;
        min-inline-size: 0;
    }

    [data-md-pane-body] > * {
        --md-layout-margin: 0px;
    }

    [data-md-pane-back] [data-md-icon]:dir(rtl) {
        transform: scaleX(-1);
    }
}