/* ========================================
   App Shell - Sidebar + Topbar Layout
   Apple HIG surfaces & grouped navigation
   ======================================== */

.app-shell {
    display: flex;
    min-height: 100vh;
    background: var(--apple-page);
    --sidebar-expanded-width: 252px;
    --sidebar-collapsed-width: 72px;
}

/* ---- Sidebar ---- */
.sidebar-rail-slot {
    width: var(--sidebar-collapsed-width);
    flex-shrink: 0;
    flex-grow: 0;
    position: relative;
}

.app-nav-sidebar {
    --sidebar-expanded-width: 252px;
    --sidebar-collapsed-width: 72px;
    width: var(--sidebar-expanded-width);
    flex-shrink: 0;
    display: flex;
    flex-direction: column;
    padding: 1rem 0.75rem;
    background: var(--apple-shell);
    border-right: 1px solid var(--apple-border);
    position: sticky;
    top: 0;
    height: 100vh;
    z-index: 200;
    overflow: hidden;
}

/* Rail mode — fixed narrow strip; layout slot never changes size */
.app-nav-sidebar.sidebar-rail {
    position: fixed;
    left: 0;
    top: 0;
    width: var(--sidebar-collapsed-width);
    height: 100vh;
    padding: 1rem 0.5rem;
    z-index: 300;
    will-change: width;
    transition:
        width 320ms cubic-bezier(0.4, 0, 0.2, 1),
        box-shadow 320ms cubic-bezier(0.4, 0, 0.2, 1),
        padding 320ms cubic-bezier(0.4, 0, 0.2, 1);
}

.app-nav-sidebar.sidebar-rail .sidebar-collapse-btn {
    display: none;
}

[data-theme="dark"] .app-nav-sidebar {
    background: var(--app-sidebar-bg, #101010);
    border-right-color: rgba(255, 255, 255, 0.08);
}

html[data-theme="light"] .app-nav-sidebar,
html:not([data-theme="dark"]) .app-nav-sidebar {
    background: var(--app-chrome-bg, #eeedea);
}

.app-nav-sidebar.collapsed {
    width: var(--sidebar-collapsed-width);
    padding: 1rem 0.5rem;
}

/* Brand + collapse row */
.sidebar-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    padding: 0.25rem 0.375rem 1.25rem;
    min-height: 2.5rem;
}

.sidebar-brand-row {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    min-width: 0;
    flex: 1;
    border: none;
    background: transparent;
    padding: 0;
    cursor: default;
    font-family: inherit;
    text-align: left;
}

.app-nav-sidebar.collapsed .sidebar-brand-row {
    cursor: pointer;
    flex: 0;
    justify-content: center;
}

.sidebar-logo-mark {
    width: 2rem;
    height: 2rem;
    border-radius: 0.625rem;
    background: linear-gradient(135deg, #2c8fea 0%, #5ca3ec 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 0.875rem;
    flex-shrink: 0;
    box-shadow: 0 2px 8px rgba(44, 143, 234, 0.25);
}

[data-theme="dark"] .sidebar-logo-mark {
    box-shadow: 0 2px 8px rgba(44, 143, 234, 0.2);
}

.sidebar-brand-name {
    font-size: 0.9375rem;
    font-weight: 600;
    color: var(--apple-text);
    letter-spacing: -0.02em;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.sidebar-collapse-btn {
    width: 2rem;
    height: 2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 1px solid var(--apple-border);
    border-radius: var(--radius-md);
    background: var(--apple-elevated);
    color: var(--apple-muted);
    cursor: pointer;
    flex-shrink: 0;
    font-size: 0.8125rem;
    transition: background var(--transition-fast), color var(--transition-fast), border-color var(--transition-fast);
}

.sidebar-collapse-btn:hover {
    background: var(--apple-hover);
    color: var(--apple-text);
}

.app-nav-sidebar.collapsed .sidebar-brand-name,
.app-nav-sidebar.collapsed .sidebar-section-label,
.app-nav-sidebar.collapsed .sidebar-section-toggle,
.app-nav-sidebar.collapsed .sidebar-nav-item span {
    opacity: 0;
    width: 0;
    overflow: hidden;
    white-space: nowrap;
    display: none;
}

.app-nav-sidebar.collapsed .sidebar-collapse-btn {
    display: none;
}

.app-nav-sidebar.collapsed .sidebar-top {
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding-bottom: 1rem;
    gap: 0;
}

.app-nav-sidebar.collapsed .sidebar-section-header {
    display: none;
}

.app-nav-sidebar.collapsed .sidebar-nav {
    gap: 0.375rem;
    align-items: center;
}

.app-nav-sidebar.collapsed .sidebar-section {
    width: 100%;
}

.app-nav-sidebar.collapsed .sidebar-section-items {
    display: flex !important;
    flex-direction: column;
    gap: 0.375rem;
    align-items: center;
}

.app-nav-sidebar.collapsed .sidebar-nav-item {
    justify-content: center;
    align-items: center;
    width: 2.5rem;
    height: 2.5rem;
    padding: 0;
    flex-shrink: 0;
}

.app-nav-sidebar.collapsed .sidebar-nav-item i {
    margin: 0;
    font-size: 1rem;
}

/* Hover expand — overlay only; rail slot stays 72px so main content never shifts */
.app-nav-sidebar.sidebar-rail.collapsed:hover {
    width: var(--sidebar-expanded-width);
    padding: 1rem 0.75rem;
    box-shadow: 8px 0 32px rgba(0, 0, 0, 0.12);
}

[data-theme="dark"] .app-nav-sidebar.sidebar-rail.collapsed:hover {
    box-shadow: 8px 0 36px rgba(0, 0, 0, 0.5);
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-brand-name,
.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-section-label,
.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-section-toggle,
.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-nav-item span {
    display: inline;
    opacity: 1;
    width: auto;
    transition: opacity 180ms cubic-bezier(0.4, 0, 0.2, 1) 80ms;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-top {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    padding: 0.25rem 0.375rem 1.25rem;
    gap: 0.5rem;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-brand-row {
    cursor: default;
    flex: 1;
    justify-content: flex-start;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-section-header {
    display: flex;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-nav {
    gap: 0.75rem;
    align-items: stretch;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-section-items {
    align-items: stretch;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-nav-item {
    justify-content: flex-start;
    width: auto;
    height: auto;
    padding: 0.5rem 0.625rem;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-nav-item i {
    margin-right: 0.625rem;
}

.app-nav-sidebar.sidebar-rail.collapsed:hover .sidebar-nav-item.active::after {
    display: block;
}

.app-nav-sidebar.sidebar-rail.collapsed .sidebar-brand-name,
.app-nav-sidebar.sidebar-rail.collapsed .sidebar-section-label,
.app-nav-sidebar.sidebar-rail.collapsed .sidebar-section-toggle,
.app-nav-sidebar.sidebar-rail.collapsed .sidebar-nav-item span {
    transition: opacity 200ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Section groups */
.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding-right: 0.125rem;
}

.sidebar-section {
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
}

.sidebar-section-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    padding: 0.375rem 0.625rem;
    border: none;
    background: transparent;
    cursor: pointer;
    font-family: inherit;
    text-align: left;
}

.sidebar-section-label {
    font-size: 0.6875rem;
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--apple-muted);
    transition: opacity var(--transition-fast);
}

.sidebar-section-toggle {
    font-size: 0.625rem;
    color: var(--apple-muted);
    transition: opacity var(--transition-fast);
}

.sidebar-section.collapsed .sidebar-section-items {
    display: none;
}

.sidebar-section.collapsed .sidebar-section-toggle.fa-minus::before {
    content: none;
}

.sidebar-section.collapsed .sidebar-section-toggle {
    font-size: 0.625rem;
}

.sidebar-section-items {
    display: flex;
    flex-direction: column;
    gap: 0.125rem;
}

.sidebar-nav-item {
    display: flex;
    align-items: center;
    gap: 0.625rem;
    padding: 0.5625rem 0.75rem;
    border-radius: var(--radius-lg);
    color: var(--apple-muted);
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    border: none;
    background: transparent;
    cursor: pointer;
    width: 100%;
    text-align: left;
    font-family: inherit;
    position: relative;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.sidebar-nav-item i {
    width: 1.125rem;
    text-align: center;
    font-size: 0.9375rem;
    flex-shrink: 0;
}

.sidebar-nav-item span {
    transition: opacity var(--transition-fast), width var(--transition-fast);
}

.sidebar-nav-item:hover {
    background: var(--apple-hover);
    color: var(--apple-text);
}

.sidebar-nav-item.active {
    background: var(--apple-elevated);
    color: var(--apple-blue);
    border: 1px solid var(--apple-border);
}

.sidebar-nav-item.active::after {
    content: '';
    position: absolute;
    right: -0.75rem;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 1.25rem;
    background: var(--apple-blue);
    border-radius: 2px 0 0 2px;
}

.app-nav-sidebar.collapsed .sidebar-nav-item.active::after {
    display: none;
}

[data-theme="dark"] .sidebar-nav-item.active {
    background: rgba(44, 143, 234, 0.12);
    border-color: rgba(255, 255, 255, 0.08);
}

/* ---- Main column ---- */
.app-main-column {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    min-height: 100vh;
}

.app-main-column > .main {
    flex: 1;
    min-height: 0;
    display: flex;
    flex-direction: column;
}

.app-topbar {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--spacing-md);
    height: var(--topbar-height);
    padding: 0 var(--spacing-lg);
    background: var(--apple-shell);
    border-bottom: 1px solid var(--apple-border);
    position: sticky;
    top: 0;
    z-index: 40;
    flex-shrink: 0;
}

html[data-theme="light"] .app-topbar,
html:not([data-theme="dark"]) .app-topbar {
    background: var(--app-chrome-bg, #eeedea);
}

[data-theme="dark"] .app-topbar {
    background: var(--app-header-bg, #101010);
    border-bottom-color: rgba(255, 255, 255, 0.08);
}

.app-page-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--apple-text);
    letter-spacing: -0.02em;
    margin: 0;
    flex-shrink: 0;
    z-index: 1;
}

.app-topbar-center {
    position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 2;
    pointer-events: none;
}

.app-topbar-center .playground-mode-toggle {
    pointer-events: auto;
}

.app-topbar-actions {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    margin-left: auto;
    flex-shrink: 0;
    z-index: 1;
}

.app-topbar .theme-toggle-btn {
    width: 2.25rem;
    height: 2.25rem;
    border-radius: var(--radius-lg);
    border: 1px solid var(--apple-border);
    background: var(--apple-elevated);
    color: var(--apple-muted);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: background var(--transition-fast), color var(--transition-fast);
}

.app-topbar .theme-toggle-btn:hover {
    background: var(--apple-hover);
    color: var(--apple-text);
}

/* Settings Page */
.settings-page-section {
    max-width: 1600px;
    margin: 0 auto;
    width: 100%;
    padding: 24px 32px 40px;
    box-sizing: border-box;
}

.settings-page-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-lg);
}

.settings-page-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--spacing-lg);
    flex-wrap: wrap;
}

.settings-page-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--apple-text);
    letter-spacing: -0.02em;
    margin: 0 0 0.25rem;
}

.settings-page-subtitle {
    font-size: 0.9375rem;
    color: var(--apple-muted);
    margin: 0;
}

.settings-page-actions {
    display: flex;
    gap: 0.5rem;
    flex-shrink: 0;
}

.settings-page-tabs {
    display: flex;
    gap: 0.25rem;
    padding: 0.25rem;
    background: var(--apple-card);
    border: 1px solid var(--apple-border);
    border-radius: var(--radius-2xl);
    width: fit-content;
}

.settings-page-tab {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    min-height: var(--btn-height);
    padding: var(--btn-padding-y) var(--btn-padding-x);
    border: none;
    background: transparent;
    border-radius: var(--btn-radius);
    color: var(--apple-muted);
    font-size: var(--btn-font-size);
    font-weight: var(--btn-font-weight);
    cursor: pointer;
    font-family: inherit;
    transition: all var(--transition-fast);
}

.settings-page-tab:hover {
    background: var(--apple-hover);
    color: var(--apple-text);
}

.settings-page-tab.active {
    background: var(--apple-elevated);
    color: var(--apple-blue);
    box-shadow: var(--shadow-sm);
}

.settings-page-card {
    background: var(--apple-card);
    border: 1px solid var(--apple-border);
    border-radius: var(--radius-2xl);
    overflow: hidden;
}

.settings-page-card .settings-body {
    padding: var(--spacing-xl);
    max-height: none;
    overflow-y: visible;
}

.settings-contacts-panel {
    padding: var(--spacing-xl);
}

.settings-contacts-panel .contacts-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.settings-contacts-panel .contacts-header h3 {
    margin: 0 0 0.25rem;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--apple-text);
}

.templates-main-card,
.kb-form-card,
.kb-entries-card {
    background: var(--apple-card);
    border: 1px solid var(--apple-border);
    border-radius: var(--radius-2xl);
}

.templates-page-header,
.kb-header {
    background: transparent;
}

@media (max-width: 768px) {
    .app-nav-sidebar:not(.collapsed) {
        position: fixed;
        left: 0;
        top: 0;
        box-shadow: var(--shadow-xl);
    }

    .app-nav-sidebar.collapsed {
        width: var(--sidebar-collapsed-width);
    }
}