/* App shell: top app bar, nav rail, main content area, mobile hamburger drawer.
   The shell is hidden when the auth screen is visible. */

.app-shell {
    display: grid;
    grid-template-columns: var(--nav-rail-width) 1fr;
    grid-template-rows: var(--app-bar-height) 1fr;
    grid-template-areas:
        'navrail appbar'
        'navrail main';
    min-height: 100vh;
    background: var(--color-bg);
}

/* ── App bar ───────────────────────────────────── */
.app-bar {
    grid-area: appbar;
    position: sticky;
    top: 0;
    z-index: var(--z-app-bar);
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 0 var(--space-5);
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    height: var(--app-bar-height);
}

.app-bar__hamburger {
    display: none;
}

.app-bar__brand {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    color: var(--color-primary);
    height: 36px;
    text-decoration: none;
}

.app-bar__brand [data-logo-slot] {
    display: inline-flex;
    align-items: center;
    height: 100%;
}

.app-bar__brand svg { height: 32px; width: auto; display: block; }

.app-bar__search {
    flex: 1 1 auto;
    max-width: 480px;
    margin-left: var(--space-5);
}

.app-bar__actions {
    display: flex;
    align-items: center;
    gap: var(--space-1);
    margin-left: auto;
}

/* ── Nav rail (desktop) ────────────────────────── */
.nav-rail {
    grid-area: navrail;
    position: sticky;
    top: 0;
    z-index: var(--z-nav);
    height: 100vh;
    width: var(--nav-rail-width);
    background: var(--color-surface);
    border-right: 1px solid var(--color-border);
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: var(--space-3) 0;
    gap: var(--space-2);
}

.nav-rail__item {
    width: 56px;
    height: 56px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2px;
    background: transparent;
    border: none;
    color: var(--color-text-muted);
    cursor: pointer;
    border-radius: var(--radius-lg);
    transition: background var(--motion-fast) var(--ease-standard),
                color var(--motion-fast) var(--ease-standard);
    text-decoration: none;
    font: inherit;
}

.nav-rail__item:hover {
    background: var(--color-surface-tint);
    color: var(--color-text);
}

.nav-rail__item .icon { font-size: 24px; }

.nav-rail__label {
    font-size: 11px;
    font-weight: var(--weight-medium);
}

.nav-rail__item.is-active {
    color: var(--color-primary-on-container);
    background: var(--color-primary-container);
}

.nav-rail__item.is-active .icon { font-variation-settings: 'FILL' 1, 'wght' 500, 'GRAD' 0, 'opsz' 24; }

/* ── Main content ──────────────────────────────── */
.app-main {
    grid-area: main;
    padding: var(--space-6);
    max-width: var(--max-content-width);
    width: 100%;
    margin: 0 auto;
}

.page-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--space-5);
    gap: var(--space-3);
    flex-wrap: wrap;
}

.page-header h1 { font-size: var(--text-display); }

/* Page transition (subtle fade) */
.page-container {
    animation: page-fade-in var(--motion-normal) var(--ease-standard);
}

@keyframes page-fade-in {
    from { opacity: 0; transform: translateY(4px); }
    to   { opacity: 1; transform: none; }
}

/* ── Mobile (≤860 px): collapse rail into hamburger drawer ── */
@media (max-width: 860px) {
    .app-shell {
        grid-template-columns: 1fr;
        grid-template-areas:
            'appbar'
            'main';
    }

    .nav-rail {
        position: fixed;
        top: 0;
        left: 0;
        width: 280px;
        max-width: 80vw;
        height: 100vh;
        transform: translateX(-100%);
        transition: transform var(--motion-normal) var(--ease-standard);
        align-items: stretch;
        padding: var(--space-3);
        z-index: var(--z-drawer);
        box-shadow: var(--elev-3);
    }

    .nav-rail.is-open { transform: none; }

    .nav-rail__item {
        width: 100%;
        height: var(--row-height);
        flex-direction: row;
        justify-content: flex-start;
        padding: 0 var(--space-4);
        gap: var(--space-3);
        border-radius: var(--radius-lg);
    }

    .nav-rail__label { font-size: var(--text-body); }

    .app-bar { padding: 0 var(--space-4); }
    .app-bar__hamburger { display: inline-flex; }
    .app-bar__search { max-width: none; margin-left: var(--space-2); }

    .nav-rail-scrim {
        position: fixed;
        inset: 0;
        background: var(--color-scrim);
        z-index: calc(var(--z-drawer) - 1);
        opacity: 0;
        pointer-events: none;
        transition: opacity var(--motion-normal) var(--ease-standard);
    }
    .nav-rail-scrim.is-open {
        opacity: 1;
        pointer-events: auto;
    }
}

@media (max-width: 520px) {
    .app-main { padding: var(--space-4); }
}