@layer layout {
    /* -------------------------------------------------------------------------
    | Utility rules for layout
    | --------------------------------------------------------------------------
    */
    .hidden {
        display: none !important;
    }

    .centered {
        text-align: center;
    }

    .pushed {
        margin-inline-start: auto;
    }

    .stack > * + * {
        margin-block-start: var(--margin-md);
    }

    .tile {
        padding: var(--pad-md);
        background-color: var(--color-background-surface);
        border-radius: var(--radius-md);
        box-shadow: var(--shadow-sm);
    }

    .tile > :first-child {
        margin-block-start: var(--margin-none);
    }

    /* -------------------------------------------------------------------------
    | Overall app Shell
    | --------------------------------------------------------------------------
    */
    .app-container {
        display: flex;
        flex-direction: column;
        block-size: 100svh;
        inline-size: 100%;
        min-inline-size: 320px;
        margin-inline: auto;
    }

    @media (min-width: 760px) {
        .app-container {
            max-inline-size: 500px;
            box-shadow: var(--shadow-lg);
            border-radius: var(--radius-lg, 12px);
        }
    }

    .app-header,
    .app-footer {
        flex: 0 0 auto;
        box-shadow: var(--shadow-sm);
        background-color: var(--color-background-surface);
    }

    .app-main {
        flex: 1 0 0%;
        overflow-y: auto;
        padding: var(--pad-md) var(--pad-sm);
        background-color: var(--color-background-app);
    }

    /* --------------------------------------------------------------------------
    | Main navigation (bottom of screen)
    |--------------------------------------------------------------------------
    */
    .main-nav {
        display: flex;
        justify-content: space-between;
        gap: var(--space-xs);
        padding: var(--pad-sm) var(--pad-none);
        margin: var(--margin-none);
    }

    .main-nav > li {
        flex: 1; /* Equal width tabs */
    }

    .main-nav > li > a {
        display: block;
        padding: var(--pad-sm) var(--pad-xs);
        color: var(--color-primary);
        text-align: center;
        text-decoration: none;
        border-radius: var(--radius-sm);
        background-color: transparent;
    }

    .main-nav > li > a:hover {
        background-color: var(--color-background-app);
    }

    /* --------------------------------------------------------------------------
    | Top navigation (top of screen)
    |--------------------------------------------------------------------------
    */
    .top-nav {
        display: flex;
        align-items: center;
        gap: var(--space-md);
        padding: var(--pad-sm) var(--pad-md);
        margin: var(--margin-none);
        background-color: transparent;
    }

    .top-nav > li > a {
        padding: var(--pad-xs) var(--pad-sm);
        color: var(--color-foreground-secondary);
        text-decoration: none;
        border-radius: var(--radius-sm);
    }

    .top-nav > li > a:hover {
        background-color: var(--color-background-app);
    }
}