/* Layout — App Shell */

*,
*::before,
*::after {
    box-sizing: border-box;
}

html,
body {
    height: 100%;
}

body.app-body {
    margin: 0;
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    color: var(--text-primary);
    background: var(--surface-body);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.app-shell {
    display: flex;
    min-height: 100vh;
}

.app-main {
    flex: 1;
    min-width: 0;
    margin-left: var(--sidebar-width);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    transition: margin-left var(--transition-normal);
}

.app-content {
    flex: 1;
    padding: var(--space-6);
}

.app-content__inner {
    max-width: var(--content-max-width);
    margin: 0 auto;
}

.app-overlay {
    position: fixed;
    inset: 0;
    background: rgba(15, 23, 42, 0.35);
    z-index: 1040;
}

/* Sidebar */
.app-sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: var(--sidebar-width);
    background: var(--surface-sidebar);
    border-right: 1px solid var(--surface-border);
    display: flex;
    flex-direction: column;
    z-index: 1050;
    transition: width var(--transition-normal), transform var(--transition-normal);
}

.app-sidebar__brand {
    height: var(--topbar-height);
    padding: 0 var(--space-4);
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--surface-border);
}

.app-sidebar__brand-link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    text-decoration: none;
    color: var(--text-primary);
    min-width: 0;
}

.app-sidebar__logo {
    flex-shrink: 0;
    border-radius: var(--border-radius-sm);
}

.app-sidebar__brand-text {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-semibold);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.app-sidebar__nav {
    flex: 1;
    overflow-y: auto;
    padding: var(--space-4) var(--space-3);
}

.app-sidebar__section {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--text-muted);
    padding: var(--space-4) var(--space-3) var(--space-2);
}

.app-sidebar__menu {
    list-style: none;
    margin: 0;
    padding: 0;
}

.app-sidebar__item + .app-sidebar__item {
    margin-top: var(--space-1);
}

.app-sidebar__link {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 0.625rem var(--space-3);
    border-radius: var(--border-radius-sm);
    color: var(--text-secondary);
    text-decoration: none;
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: background var(--transition-fast), color var(--transition-fast);
}

.app-sidebar__link:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

.app-sidebar__link.is-active {
    background: color-mix(in srgb, var(--brand-primary) 12%, transparent);
    color: var(--brand-primary);
    font-weight: var(--font-weight-semibold);
}

.app-sidebar__icon {
    font-size: 1.125rem;
    width: 1.25rem;
    text-align: center;
    flex-shrink: 0;
}

.app-sidebar__footer {
    padding: var(--space-3);
    border-top: 1px solid var(--surface-border);
}

.app-sidebar__collapse-btn {
    width: 100%;
    display: flex;
    align-items: center;
    gap: var(--space-3);
    padding: 0.625rem var(--space-3);
    margin-top: var(--space-2);
    border: none;
    background: transparent;
    border-radius: var(--border-radius-sm);
    color: var(--text-muted);
    font-size: var(--font-size-sm);
    cursor: pointer;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.app-sidebar__collapse-btn:hover {
    background: var(--surface-hover);
    color: var(--text-primary);
}

.app-sidebar__item--logout .app-sidebar__link {
    color: var(--color-danger);
}

.app-sidebar__item--logout .app-sidebar__link:hover {
    background: var(--color-danger-bg);
    color: var(--color-danger);
}

/* Collapsed sidebar */
body.sidebar-collapsed .app-sidebar {
    width: var(--sidebar-collapsed-width);
}

body.sidebar-collapsed .app-main {
    margin-left: var(--sidebar-collapsed-width);
}

body.sidebar-collapsed .app-sidebar__brand-text,
body.sidebar-collapsed .app-sidebar__label,
body.sidebar-collapsed .app-sidebar__section {
    display: none;
}

body.sidebar-collapsed .app-sidebar__brand-link {
    justify-content: center;
}

body.sidebar-collapsed .app-sidebar__link,
body.sidebar-collapsed .app-sidebar__collapse-btn {
    justify-content: center;
    padding-left: 0;
    padding-right: 0;
}

/* Topbar */
.app-topbar {
    position: sticky;
    top: 0;
    z-index: 1030;
    height: var(--topbar-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
    padding: 0 var(--space-6);
    background: var(--surface-topbar);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--surface-border);
}

.app-topbar__start,
.app-topbar__end {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    min-width: 0;
}

.app-topbar__end {
    flex-shrink: 0;
}

.app-topbar__menu-btn {
    display: none;
    width: 40px;
    height: 40px;
    border: 1px solid var(--surface-border);
    border-radius: var(--border-radius-sm);
    background: var(--surface-panel);
    color: var(--text-secondary);
    cursor: pointer;
}

.app-topbar__search {
    position: relative;
    width: 280px;
}

.app-topbar__search-icon {
    position: absolute;
    left: 12px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--text-muted);
    pointer-events: none;
}

.app-topbar__search-input {
    width: 100%;
    height: 40px;
    padding: 0 var(--space-3) 0 2.25rem;
    border: 1px solid var(--surface-border);
    border-radius: var(--border-radius);
    background: var(--gray-50);
    font-size: var(--font-size-sm);
    color: var(--text-primary);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.app-topbar__search-input:focus {
    outline: none;
    border-color: color-mix(in srgb, var(--brand-primary) 40%, var(--surface-border));
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--brand-primary) 12%, transparent);
}

.app-topbar__icon-btn {
    position: relative;
    width: 40px;
    height: 40px;
    border: 1px solid var(--surface-border);
    border-radius: var(--border-radius-sm);
    background: var(--surface-panel);
    color: var(--text-secondary);
    cursor: pointer;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.app-topbar__icon-btn:hover:not(:disabled) {
    background: var(--surface-hover);
    color: var(--text-primary);
}

.app-topbar__icon-btn:disabled {
    opacity: 0.55;
    cursor: not-allowed;
}

.app-topbar__badge {
    position: absolute;
    top: 4px;
    right: 4px;
    min-width: 16px;
    height: 16px;
    padding: 0 4px;
    border-radius: 999px;
    background: var(--brand-primary);
    color: var(--text-inverse);
    font-size: 10px;
    font-weight: var(--font-weight-semibold);
    line-height: 16px;
    text-align: center;
}

.app-topbar__avatar {
    width: 36px;
    height: 36px;
    border-radius: 999px;
    background: color-mix(in srgb, var(--brand-primary) 15%, white);
    color: var(--brand-primary);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.app-topbar__user-meta {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    line-height: 1.2;
    text-align: left;
}

.app-topbar__user-name {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--text-primary);
}

.app-topbar__user-role {
    font-size: var(--font-size-xs);
    color: var(--text-muted);
}

.app-topbar__chevron {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Footer */
.app-footer {
    height: var(--footer-height);
    padding: 0 var(--space-6);
    border-top: 1px solid var(--surface-border);
    background: var(--surface-panel);
}

.app-footer__inner {
    max-width: var(--content-max-width);
    margin: 0 auto;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-4);
    font-size: var(--font-size-xs);
    color: var(--text-muted);
}

.app-footer__link {
    color: var(--brand-primary);
    text-decoration: none;
}

.app-footer__link:hover {
    text-decoration: underline;
}

/* Error page layout */
body.app-body--error {
    background: var(--surface-body);
}

.error-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--space-8);
}

.error-state {
    text-align: center;
    max-width: 480px;
}

.error-state__code {
    font-size: 4rem;
    font-weight: var(--font-weight-bold);
    line-height: 1;
    color: color-mix(in srgb, var(--brand-primary) 70%, var(--gray-400));
}

.error-state__title {
    margin: var(--space-4) 0 var(--space-2);
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-semibold);
}

.error-state__message {
    margin: 0 0 var(--space-6);
    color: var(--text-secondary);
}

.error-state__actions {
    display: flex;
    justify-content: center;
}

/* Responsive */
@media (max-width: 1199.98px) {
    .app-topbar__search {
        width: 220px;
    }
}

@media (max-width: 991.98px) {
    .app-main {
        margin-left: 0;
    }

    .app-sidebar {
        transform: translateX(-100%);
    }

    body.sidebar-mobile-open .app-sidebar {
        transform: translateX(0);
        box-shadow: var(--shadow-lg);
    }

    body.sidebar-mobile-open .app-overlay {
        display: block;
    }

    .app-topbar__menu-btn {
        display: inline-flex;
        align-items: center;
        justify-content: center;
    }

    .app-topbar__search,
    .app-topbar__user-meta,
    .app-topbar__chevron {
        display: none;
    }

    .app-content {
        padding: var(--space-4);
    }
}

@media (max-width: 767.98px) {
    .app-topbar {
        padding: 0 var(--space-4);
    }

    .app-footer__inner {
        flex-direction: column;
        justify-content: center;
        text-align: center;
    }
}

@media (min-width: 992px) {
    body.sidebar-collapsed .app-topbar__menu-btn {
        display: none;
    }
}