/* Глобальный сброс и шрифты */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--color-bg);
    color: var(--color-text);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

/* Заголовки */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-weight: 700;
    color: var(--color-text);
    line-height: 1.25;
}

h1 {
    font-size: var(--text-4xl);
}

h2 {
    font-size: var(--text-3xl);
}

h3 {
    font-size: var(--text-2xl);
}

h4 {
    font-size: var(--text-xl);
}

/* Контейнеры */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--space-4);
    width: 100%;
}

.content-width {
    max-width: 1100px;
    margin: 0 auto;
}

.form-container {
    max-width: 480px;
    margin: var(--space-12) auto;
    background: var(--color-surface);
    padding: var(--space-8);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--color-border);
}

/* Сетка и разметка */
.flex {
    display: flex;
}

.flex-col {
    flex-direction: column;
}

.align-center {
    align-items: center;
}

.justify-between {
    justify-content: space-between;
}

.justify-center {
    justify-content: center;
}

.gap-2 {
    gap: var(--space-2);
}

.gap-4 {
    gap: var(--space-4);
}

.gap-6 {
    gap: var(--space-6);
}

.grid {
    display: grid;
    gap: var(--space-6);
}

.grid-2 {
    grid-template-columns: repeat(2, 1fr);
}

.grid-3 {
    grid-template-columns: repeat(3, 1fr);
}

@media (max-width: 768px) {

    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }
}

/* Кнопки */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    height: 48px;
    padding: 0 var(--space-6);
    font-size: var(--text-base);
    font-weight: 600;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid transparent;
    text-decoration: none;
    gap: var(--space-2);
}

.btn-primary {
    background-color: var(--color-primary-600);
    color: #ffffff;
}

.btn-primary:hover {
    background-color: var(--color-primary-700);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.2);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    background-color: var(--color-surface);
    border-color: var(--color-border);
    color: var(--color-text-soft);
}

.btn-secondary:hover {
    background-color: var(--color-surface-soft);
    border-color: var(--color-border-strong);
}

.btn-student {
    background-color: var(--color-secondary-600);
    color: #ffffff;
    font-family: 'Outfit', sans-serif;
    border-radius: var(--radius-lg);
    box-shadow: 0 4px 6px rgba(124, 58, 237, 0.1);
}

.btn-student:hover {
    background-color: var(--color-secondary-500);
    transform: translateY(-2px) scale(1.02);
    box-shadow: 0 8px 20px rgba(124, 58, 237, 0.3);
}

.btn-danger {
    background-color: var(--color-danger-500);
    color: #ffffff;
}

.btn-danger:hover {
    background-color: var(--color-danger-500);
    opacity: 0.9;
}

/* Shared accessible states. Pages compose these primitives; they do not copy a shell. */
.ui-card { background: var(--color-surface); border: 1px solid var(--color-border); border-radius: var(--radius-lg); box-shadow: var(--shadow-sm); }
.ui-empty, .ui-error { padding: var(--space-8); text-align: center; color: var(--color-text-muted); }
.ui-error { color: var(--color-danger-500); border: 1px solid var(--color-danger-400); background: #fff5f5; }
.ui-sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.btn:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible { outline: 2px solid var(--ui-focus-ring); outline-offset: 2px; box-shadow: var(--shadow-focus); }
.btn[aria-disabled="true"], .btn:disabled { cursor: not-allowed; opacity: .55; transform: none; box-shadow: none; }

/* Forms and data-display primitives.  Behaviour is native HTML/HTMX; no onclick API. */
.ui-select { appearance: auto; }
.ui-input-error { border-color: var(--color-danger-500); }
.ui-input-error:focus { border-color: var(--color-danger-500); box-shadow: 0 0 0 3px rgb(220 38 38 / .2); }
.ui-help { display: block; margin-top: var(--space-1); color: var(--color-text-muted); font-size: var(--text-sm); }
.ui-help-error { color: var(--color-danger-500); }
.ui-table-wrap { overflow-x: auto; border: 1px solid var(--color-border); border-radius: var(--radius-lg); background: var(--color-surface); }
.ui-table { width: 100%; border-collapse: collapse; font-size: var(--text-sm); }
.ui-table th, .ui-table td { padding: var(--space-3) var(--space-4); text-align: left; border-bottom: 1px solid var(--color-border); }
.ui-table th { color: var(--color-text-soft); background: var(--color-surface-soft); font-weight: 700; }
.ui-table tr:last-child td { border-bottom: 0; }
.ui-table__primary-link { color: var(--color-primary-600); font-weight: 700; text-decoration: none; }
.ui-table__primary-link:hover { text-decoration: underline; }
.ui-table__meta { margin-top: var(--space-1); color: var(--color-text-muted); font-size: var(--text-xs); }
.ui-filter-bar { display: flex; align-items: end; gap: var(--space-4); padding: var(--space-4); flex-wrap: wrap; }
.ui-filter-bar > div { display: grid; gap: var(--space-1); }
.ui-filter-bar label { font-size: var(--text-sm); font-weight: 700; }
.ui-filter-bar__actions { display: flex !important; gap: var(--space-2); }
.ui-priority { font-size: var(--text-sm); font-weight: 700; }
.ui-priority--high { color: var(--color-danger-500); }
.ui-priority--medium { color: #a16207; }
.ui-priority--low { color: var(--color-text-muted); }
.ui-stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: var(--space-4); }
.ui-stat { display: grid; gap: var(--space-1); padding: var(--space-4); border-left: 4px solid var(--color-primary-500); }
.ui-stat span { color: var(--color-text-muted); font-size: var(--text-sm); font-weight: 700; }
.ui-stat strong { color: var(--color-text); font-size: var(--text-2xl); }
.ui-stat--danger { border-left-color: var(--color-danger-500); }
.ui-tabs a.ui-tab { display: inline-flex; align-items: center; text-decoration: none; }
.ui-tabs a.ui-tab[aria-current="page"] { color: var(--ui-primary); border-bottom-color: var(--ui-primary); }
.ui-inline-form { display: inline-block; margin-left: var(--space-2); }
.ui-code-block { max-width: min(600px, 70vw); max-height: 22rem; overflow: auto; margin: var(--space-2) 0 0; padding: var(--space-3); border: 1px solid var(--color-border); border-radius: var(--radius-md); background: var(--color-surface-soft); font-size: var(--text-xs); white-space: pre-wrap; overflow-wrap: anywhere; }
.ui-grid { display: grid; gap: var(--space-4); }
.ui-grid--two { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.ui-stack--compact { gap: var(--space-2); }
.ui-split { display: flex; justify-content: space-between; gap: var(--space-3); align-items: baseline; }
.ui-progress { height: 0.5rem; overflow: hidden; border-radius: var(--radius-pill); background: var(--color-border); }
.ui-progress > span { display: block; height: 100%; border-radius: inherit; background: var(--ui-primary); }
.ui-definition-list { display: grid; gap: var(--space-2); margin: var(--space-3) 0 0; font-size: var(--text-sm); }
.ui-definition-list div { display: grid; grid-template-columns: minmax(6rem, 0.35fr) 1fr; gap: var(--space-2); }
.ui-definition-list dt { color: var(--color-text-muted); }
.ui-definition-list dd { margin: 0; }
@media (max-width: 768px) { .ui-grid--two { grid-template-columns: 1fr; } .ui-definition-list div { grid-template-columns: 1fr; gap: 0; } }
.ui-badge { display: inline-flex; align-items: center; min-height: 24px; padding: 0 var(--space-2); border-radius: var(--radius-pill); background: var(--color-surface-soft); color: var(--color-text-soft); font-size: var(--text-xs); font-weight: 700; }
.ui-badge-success { background: #dcfce7; color: #166534; }
.ui-badge-warning { background: #fef3c7; color: #92400e; }
.ui-badge-danger { background: #fee2e2; color: #991b1b; }
.ui-tabs { display: flex; gap: var(--space-1); border-bottom: 1px solid var(--color-border); overflow-x: auto; }
.ui-tab { border: 0; border-bottom: 2px solid transparent; padding: var(--space-3) var(--space-4); background: transparent; color: var(--color-text-muted); font: inherit; font-weight: 600; white-space: nowrap; }
.ui-tab[aria-selected="true"] { color: var(--ui-primary); border-bottom-color: var(--ui-primary); }
.ui-pagination { display: flex; align-items: center; gap: var(--space-2); }
.ui-pagination a, .ui-pagination span { min-width: 36px; min-height: 36px; display: inline-grid; place-items: center; border-radius: var(--radius-sm); }
.ui-pagination a { color: var(--color-primary-600); text-decoration: none; }
.ui-pagination [aria-current="page"] { background: var(--color-primary-600); color: white; }
.ui-skeleton { border-radius: var(--radius-sm); background: linear-gradient(90deg, var(--color-surface-soft), #e2e8f0, var(--color-surface-soft)); background-size: 200% 100%; animation: ui-shimmer 1.4s ease-in-out infinite; }
.ui-toast { position: relative; padding: var(--space-4); border-radius: var(--radius-md); border: 1px solid var(--color-border); background: var(--color-surface); box-shadow: var(--shadow-md); }
.ui-toast[role="alert"] { border-color: var(--color-danger-400); }
.ui-toast--error { border-color: var(--color-danger-400); color: var(--color-danger-500); }
.ui-modal[hidden] { display: none; }
.ui-modal { position: fixed; z-index: 1000; inset: 0; display: grid; place-items: center; padding: var(--space-4); background: rgb(15 23 42 / .55); }
.ui-modal__dialog { max-width: 560px; width: 100%; padding: var(--space-6); border-radius: var(--radius-lg); background: var(--color-surface); box-shadow: var(--shadow-lg); }
.ui-stack { display: grid; gap: var(--space-5); }
.ui-page-heading { margin-bottom: var(--space-6); }
.ui-page-heading h1, .ui-course-card h2, .ui-curriculum-section h3, .ui-curriculum-section h4 { margin: 0; color: var(--color-text); }
.ui-page-heading p, .ui-course-card__header p { color: var(--color-text-muted); }
.ui-course-card { padding: var(--space-6); }
.ui-course-card__header, .ui-lesson-row { display: flex; gap: var(--space-4); justify-content: space-between; align-items: center; }
.ui-progress { height: 8px; margin: var(--space-4) 0 var(--space-2); overflow: hidden; border-radius: var(--radius-pill); background: var(--color-surface-soft); }
.ui-progress > span { display: block; height: 100%; border-radius: inherit; background: var(--color-success-500); }
.ui-curriculum-section { padding-top: var(--space-5); }
.ui-curriculum-section h4 { margin: var(--space-4) 0 var(--space-2); font-size: var(--text-base); }
.ui-lesson-list { display: grid; gap: var(--space-2); margin: 0; padding: 0; list-style: none; }
.ui-lesson-row { padding: var(--space-3); border: 1px solid var(--color-border); border-radius: var(--radius-md); }
.ui-lesson-row strong { display: block; }
.ui-lesson-element { padding: var(--space-6); overflow: hidden; }
.ui-lesson-element h2 { margin-top: 0; }
.ui-lesson-element video, .ui-lesson-element audio { width: 100%; }
.ui-embed { width: 100%; min-height: min(60vw, 540px); border: 0; border-radius: var(--radius-md); }
.ui-gallery { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: var(--space-3); }
.ui-gallery img { width: 100%; height: auto; border-radius: var(--radius-md); }
.ui-lesson-runtime textarea, .ui-lesson-runtime input, .ui-card textarea, .ui-card input { width: 100%; }
.ui-card label { display: grid; gap: var(--space-2); font-weight: 600; }
.ui-choice { grid-template-columns: auto 1fr !important; align-items: center; padding: var(--space-2) 0; }
.ui-choice input { width: auto; }
@media (max-width: 575px) { .ui-course-card { padding: var(--space-4); } .ui-course-card__header, .ui-lesson-row { align-items: flex-start; flex-direction: column; } .ui-lesson-row .btn { width: 100%; } }
@keyframes ui-shimmer { to { background-position: -200% 0; } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation-duration: .01ms !important; animation-iteration-count: 1 !important; transition-duration: .01ms !important; scroll-behavior: auto !important; } }

.ui-skip-link { position: absolute; left: var(--space-4); top: -64px; z-index: 2000; padding: var(--space-3); background: var(--color-surface); color: var(--color-primary-700); border-radius: var(--radius-sm); box-shadow: var(--shadow-md); }
.ui-skip-link:focus { top: var(--space-4); }
.ui-drawer-toggle, .ui-drawer-close { border: 0; background: transparent; color: inherit; padding: var(--space-2); cursor: pointer; }
.ui-drawer-overlay { display: none; }
.legacy-confirm { position: fixed; z-index: 2000; inset: 0; display: grid; place-items: center; padding: var(--space-4); background: rgb(15 23 42 / .65); }
.legacy-confirm[hidden] { display: none; }
.legacy-confirm__dialog { width: min(420px, 100%); padding: var(--space-8); text-align: center; border: 3px solid var(--color-border); border-radius: var(--radius-xl); background: var(--color-surface); box-shadow: var(--shadow-lg); }
.legacy-confirm__actions { display: flex; gap: var(--space-3); }
.legacy-confirm__actions > * { flex: 1; }
@media (max-width: 768px) {
  .ui-drawer { position: fixed; z-index: 1500; inset: 0 auto 0 0; width: min(320px, 85vw); transform: translateX(-105%); transition: transform .2s ease; }
  .ui-drawer-overlay { position: fixed; z-index: 1400; inset: 0; background: rgb(15 23 42 / .55); }
  .ui-drawer-open .ui-drawer { transform: translateX(0); }
  .ui-drawer-open .ui-drawer-overlay { display: block; }
  .ui-drawer-open { overflow: hidden; }
}

/* Формы */
.form-group {
    margin-bottom: var(--space-5);
}

.form-label {
    display: block;
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-text-soft);
    margin-bottom: var(--space-2);
}

.form-control {
    width: 100%;
    height: 44px;
    padding: 0 var(--space-4);
    font-size: var(--text-base);
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    color: var(--color-text);
    transition: all 0.15s ease-in-out;
}

.form-control:focus {
    outline: none;
    border-color: var(--color-primary-500);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.15);
}

/* Карточки */
.card {
    background-color: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    box-shadow: var(--shadow-sm);
    transition: all 0.2s ease-in-out;
}

.card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--color-border-strong);
}

/* Student-specific Cards */
.card-student {
    border-radius: var(--radius-xl);
    border: 2px solid var(--color-border);
    box-shadow: 0 8px 0 var(--color-border);
    transition: all 0.2s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.card-student:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 0 var(--color-border-strong);
    border-color: var(--color-border-strong);
}

/* Бейджи */
.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--space-1) var(--space-3);
    font-size: var(--text-xs);
    font-weight: 600;
    border-radius: var(--radius-pill);
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.badge-info {
    background-color: #e0f2fe;
    color: #0369a1;
}

.badge-success {
    background-color: #dcfce7;
    color: #15803d;
}

.badge-warning {
    background-color: #fef3c7;
    color: #b45309;
}

.badge-danger {
    background-color: #fee2e2;
    color: #b91c1c;
}

/* Навигационные панели */
.navbar {
    height: 72px;
    background-color: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
}

.brand {
    font-family: 'Outfit', sans-serif;
    font-size: var(--text-2xl);
    font-weight: 800;
    color: var(--color-primary-600);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: var(--space-2);
}

.brand-student {
    color: var(--color-secondary-600);
}

/* Дашборд преподавателя */
.app-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    min-height: 100vh;
}

@media (max-width: 1024px) {
    .app-layout {
        grid-template-columns: 1fr;
    }
}

.sidebar {
    background-color: var(--color-surface);
    border-right: 1px solid var(--color-border);
    padding: var(--space-6);
    display: flex;
    flex-direction: column;
    gap: var(--space-8);
}

.sidebar-nav {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: var(--space-2);
}

.sidebar-link {
    display: flex;
    align-items: center;
    padding: var(--space-3) var(--space-4);
    color: var(--color-text-soft);
    text-decoration: none;
    font-weight: 500;
    border-radius: var(--radius-md);
    transition: all 0.15s ease;
    gap: var(--space-3);
}

.sidebar-link:hover,
.sidebar-link.active {
    background-color: var(--color-primary-50);
    color: var(--color-primary-700);
}

.sidebar-guide-item {
    border-bottom: 1px solid var(--color-border);
    margin-bottom: var(--space-2);
    padding-bottom: var(--space-2);
}

.sidebar-link-muted {
    color: var(--color-text-muted);
}

.sidebar-link-muted:hover,
.sidebar-link-muted.active {
    background-color: var(--color-surface-soft);
    color: var(--color-text-soft);
}

.main-content {
    padding: var(--space-8) var(--space-12);
    background-color: var(--color-bg);
    min-width: 0;
}

@media (max-width: 1024px) {
    .main-content {
        padding: var(--space-6);
    }
}


/* Лендинг */
.hero {
    padding: var(--space-16) 0;
    text-align: center;
    background: radial-gradient(circle at 50% 50%, var(--color-primary-50) 0%, transparent 60%);
}

.hero-title {
    font-family: 'Outfit', sans-serif;
    font-size: 54px;
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: var(--space-4);
    background: linear-gradient(135deg, var(--color-primary-700) 0%, var(--color-secondary-600) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: var(--text-xl);
    color: var(--color-text-soft);
    max-width: 600px;
    margin: 0 auto var(--space-8) auto;
}

/* Мобильная адаптация */
.mobile-navbar {
    display: none;
}

.sidebar-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.sidebar-close-btn {
    display: none;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--space-8);
    gap: var(--space-4);
}

@media (max-width: 1024px) {
    .mobile-navbar {
        display: flex;
        align-items: center;
        justify-content: space-between;
        height: 64px;
        padding: 0 var(--space-6);
        background-color: var(--color-surface);
        border-bottom: 1px solid var(--color-border);
        position: sticky;
        top: 0;
        z-index: 99;
    }

    .mobile-menu-toggle {
        display: flex;
        align-items: center;
        justify-content: center;
        width: 40px;
        height: 40px;
        background: none;
        border: none;
        cursor: pointer;
        color: var(--color-text);
        border-radius: var(--radius-md);
        transition: background-color 0.2s;
    }

    .mobile-menu-toggle:hover {
        background-color: var(--color-surface-soft);
    }

    .mobile-menu-toggle i {
        width: 24px;
        height: 24px;
    }

    .sidebar-close-btn {
        display: flex;
        align-items: center;
        justify-content: center;
        width: 36px;
        height: 36px;
        background: none;
        border: none;
        cursor: pointer;
        color: var(--color-text-soft);
        border-radius: var(--radius-md);
        transition: background-color 0.2s;
    }

    .sidebar-close-btn:hover {
        background-color: var(--color-surface-soft);
    }

    .sidebar-close-btn i {
        width: 20px;
        height: 20px;
    }

    .sidebar {
        position: fixed;
        top: 0;
        left: 0;
        bottom: 0;
        width: 280px;
        z-index: 1000;
        transform: translateX(-100%);
        transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        box-shadow: var(--shadow-lg);
    }

    .sidebar.sidebar-open {
        transform: translateX(0);
    }

    .sidebar-overlay {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background-color: rgba(15, 23, 42, 0.4);
        backdrop-filter: blur(2px);
        z-index: 999;
    }
}

@media (max-width: 768px) {
    .main-content {
        padding: var(--space-4);
    }

    .page-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-4);
    }

    .page-header>div:last-child {
        width: 100%;
        display: flex;
        flex-direction: column;
        gap: var(--space-2);
    }

    .page-header .btn {
        width: 100%;
    }
}

/* Утилиты нового дизайна (референс html_version/styles.css) */
.glass-card {
    background-color: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.glass-panel {
    background-color: rgba(255, 255, 255, 0.7);
    backdrop-filter: blur(16px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: var(--shadow-sm);
}

.glass-button {
    background-color: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    transition: background-color 0.15s ease-in-out;
}
.glass-button:hover {
    background-color: rgba(255, 255, 255, 0.3);
}

.hover-lift {
    transition: transform 0.3s ease-in-out;
}
.hover-lift:hover {
    transform: translateY(-4px);
}

.animate-fade-in {
    animation: fade-in 0.3s ease-out;
}

@keyframes fade-in {
    from { opacity: 0; }
    to { opacity: 1; }
}



/* Backoffice Training Builder Active Component */
.builder-layout {
    display: grid;
    grid-template-columns: 320px minmax(0, 1fr);
    gap: 20px;
    align-items: start;
  }
  @media (max-width: 900px) {
    .builder-layout {
      grid-template-columns: 1fr;
    }
  }

  /* Top Toolbar */
  .builder-topbar {
    padding: 14px 20px;
    display: flex;
    gap: 12px;
    align-items: center;
    flex-wrap: wrap;
    margin-bottom: 20px;
    position: sticky;
    top: 8px;
    z-index: 10;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-sm);
  }

  /* Tree Navigation Sidebar */
  .builder-tree-panel {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 16px;
    max-height: calc(100vh - 140px);
    overflow-y: auto;
    position: sticky;
    top: 82px;
  }
  .tree-search-box {
    margin-bottom: 14px;
  }
  .tree-section {
    margin-bottom: 12px;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    background: #fafafa;
    overflow: hidden;
  }
  .tree-section-header {
    padding: 10px 12px;
    background: #f1f5f9;
    font-weight: 700;
    font-size: 13px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    user-select: none;
  }
  .tree-block {
    margin: 6px 8px;
    border-left: 2px solid var(--color-primary-300);
    padding-left: 8px;
  }
  .tree-block-title {
    font-size: 12px;
    font-weight: 600;
    color: var(--color-text-muted);
    padding: 4px 6px;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }
  .tree-lesson-item {
    padding: 8px 10px;
    border-radius: var(--radius-sm);
    font-size: 13px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    cursor: pointer;
    transition: all 0.15s ease;
    margin-top: 2px;
    border: 1px solid transparent;
  }
  .tree-lesson-item:hover {
    background: #e2e8f0;
  }
  .tree-lesson-item.active {
    background: #6366f1;
    color: #ffffff;
    font-weight: 600;
    box-shadow: 0 2px 6px rgba(99, 102, 241, 0.3);
  }
  .tree-lesson-item.active .badge-sub {
    background: rgba(255,255,255,0.2);
    color: #ffffff;
  }

  /* Main Workspace */
  .builder-workspace {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 24px;
    min-height: 600px;
  }
  .workspace-header {
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 16px;
    margin-bottom: 20px;
  }
  .workspace-tabs {
    display: flex;
    gap: 8px;
    border-bottom: 2px solid var(--color-border);
    margin-bottom: 20px;
  }
  .workspace-tab-btn {
    padding: 10px 18px;
    font-size: 14px;
    font-weight: 600;
    color: var(--color-text-muted);
    border: none;
    background: none;
    cursor: pointer;
    border-bottom: 2px solid transparent;
    margin-bottom: -2px;
    transition: all 0.2s;
  }
  .workspace-tab-btn.active {
    color: #6366f1;
    border-bottom-color: #6366f1;
  }

  /* Human-readable element cards */
  .element-card {
    background: #ffffff;
    border: 1px solid var(--color-border);
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 14px;
    box-shadow: var(--shadow-sm);
    transition: border-color 0.2s, box-shadow 0.2s;
  }
  .element-card:hover {
    border-color: #6366f1;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.08);
  }
  .element-card-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 10px;
  }
  .element-type-tag {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    border-radius: 20px;
    font-size: 12px;
    font-weight: 700;
    text-transform: uppercase;
  }
  .type-rich_text { background: #e0e7ff; color: #4338ca; }
  .type-video { background: #fee2e2; color: #b91c1c; }
  .type-audio { background: #fef3c7; color: #b45309; }
  .type-image { background: #dcfce7; color: #15803d; }
  .type-file { background: #f3e8ff; color: #6b21a8; }
  .type-other { background: #f1f5f9; color: #475569; }

  /* Human-readable test questions */
  .question-card {
    background: #f8fafc;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    padding: 16px;
    margin-bottom: 14px;
  }
  .option-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 13px;
    margin: 3px;
    background: #ffffff;
    border: 1px solid #cbd5e1;
  }
  .option-pill.correct {
    background: #dcfce7;
    border-color: #86efac;
    color: #166534;
    font-weight: 600;
  }

  /* Modals */
  .human-modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(4px);
    display: none;
    align-items: center;
    justify-content: center;
    z-index: 1000;
  }
  .human-modal.active {
    display: flex;
  }
  .human-modal-dialog {
    background: #ffffff;
    border-radius: 16px;
    width: min(640px, 92vw);
    max-height: 85vh;
    overflow-y: auto;
    padding: 24px;
    box-shadow: 0 20px 60px rgba(15, 23, 42, 0.3);
  }