/* ============================================
   陕汽管理后台 - 共享样式系统
   ============================================ */

/* CSS Variables */
:root {
  /* Primary Colors */
  --primary: #2563eb;
  --primary-light: #3b82f6;
  --primary-dark: #1d4ed8;
  --primary-bg: #eff6ff;

  /* Semantic Colors */
  --success: #10b981;
  --success-bg: #ecfdf5;
  --warning: #f59e0b;
  --warning-bg: #fffbeb;
  --danger: #ef4444;
  --danger-bg: #fef2f2;
  --info: #6366f1;
  --info-bg: #eef2ff;

  /* Neutral Colors */
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-600: #4b5563;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;

  /* Layout */
  --sidebar-width: 240px;
  --header-height: 56px;
  --border-radius: 8px;
  --border-radius-sm: 4px;
  --border-radius-lg: 12px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
  --shadow: 0 1px 3px rgba(0,0,0,0.1), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -1px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -2px rgba(0,0,0,0.05);

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans SC", sans-serif;
  --font-size-xs: 12px;
  --font-size-sm: 13px;
  --font-size-base: 14px;
  --font-size-lg: 16px;
  --font-size-xl: 18px;
  --font-size-2xl: 20px;
  --font-size-3xl: 24px;

  /* Transition */
  --transition: all 0.2s ease;
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 14px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  color: var(--gray-800);
  background: var(--gray-50);
  line-height: 1.6;
}

[hidden] {
  display: none !important;
}

a {
  color: var(--primary);
  text-decoration: none;
}

a:hover {
  color: var(--primary-dark);
}

/* ============================================
   Login Page
   ============================================ */
.login-container {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #1e3a5f 0%, #2563eb 50%, #1e40af 100%);
  padding: 20px;
}

.login-card {
  background: white;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  width: 100%;
  max-width: 420px;
  padding: 48px 40px;
}

.login-logo {
  text-align: center;
  margin-bottom: 32px;
}

.login-logo h1 {
  font-size: 24px;
  color: var(--gray-800);
  font-weight: 700;
  margin-bottom: 4px;
}

.login-logo p {
  color: var(--gray-500);
  font-size: 14px;
}

.login-form .form-group {
  margin-bottom: 20px;
}

.login-form label {
  display: block;
  font-size: 14px;
  font-weight: 500;
  color: var(--gray-700);
  margin-bottom: 6px;
}

.login-form input[type="text"],
.login-form input[type="password"] {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 14px;
  transition: var(--transition);
  outline: none;
}

.login-form input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.login-form .remember-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 24px;
}

.login-form .remember-row label {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--gray-600);
  cursor: pointer;
}

.login-form .remember-row a {
  font-size: 13px;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 8px 16px;
  border: 1px solid transparent;
  border-radius: var(--border-radius);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
  text-decoration: none;
  line-height: 1.5;
}

.btn:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow);
}

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

.btn-primary {
  background: var(--primary);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-dark);
  color: white;
}

.btn-success {
  background: var(--success);
  color: white;
}

.btn-success:hover {
  background: #059669;
  color: white;
}

.btn-warning {
  background: var(--warning);
  color: white;
}

.btn-danger {
  background: var(--danger);
  color: white;
}

.btn-danger:hover {
  background: #dc2626;
  color: white;
}

.btn-outline {
  background: white;
  color: var(--gray-700);
  border-color: var(--gray-300);
}

.btn-outline:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-ghost {
  background: transparent;
  color: var(--gray-600);
}

.btn-ghost:hover {
  background: var(--gray-100);
}

.btn-disabled,
.btn:disabled {
  background: var(--gray-100);
  color: var(--gray-400);
  border-color: transparent;
  cursor: not-allowed;
  pointer-events: none;
}

.btn-disabled:hover,
.btn:disabled:hover {
  transform: none;
  box-shadow: none;
}

.btn-sm {
  padding: 4px 10px;
  font-size: 13px;
}

.btn-lg {
  padding: 12px 24px;
  font-size: 16px;
}

.btn-block {
  width: 100%;
}

.btn-icon {
  padding: 6px;
  width: 32px;
  height: 32px;
}

/* ============================================
   Layout - Admin Shell
   ============================================ */
.admin-layout {
  display: flex;
  min-height: 100vh;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--gray-900);
  color: white;
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  z-index: 100;
  overflow-y: auto;
  transition: var(--transition);
}

.sidebar-header {
  padding: 16px 20px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
  display: flex;
  align-items: center;
  gap: 10px;
}

.sidebar-header .logo-icon {
  width: 32px;
  height: 32px;
  background: var(--primary);
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 14px;
}

.sidebar-header h2 {
  font-size: 15px;
  font-weight: 600;
}

.sidebar-header p {
  font-size: 11px;
  color: var(--gray-400);
  margin-top: 1px;
}

.sidebar-nav {
  padding: 12px 0;
}

.nav-section {
  margin-bottom: 4px;
}

.nav-section-title {
  padding: 8px 20px 4px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--gray-500);
  font-weight: 600;
}

.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 20px;
  color: var(--gray-400);
  font-size: 13px;
  transition: var(--transition);
  cursor: pointer;
  border-left: 3px solid transparent;
}

.nav-item:hover {
  background: rgba(255,255,255,0.05);
  color: var(--gray-200);
}

.nav-item.active {
  background: rgba(37, 99, 235, 0.15);
  color: white;
  border-left-color: var(--primary);
}

.nav-item .nav-icon {
  width: 18px;
  text-align: center;
  font-size: 14px;
}

.nav-item .nav-badge {
  margin-left: auto;
  background: var(--danger);
  color: white;
  font-size: 11px;
  padding: 1px 6px;
  border-radius: 10px;
}

.nav-children {
  display: none;
}

.nav-children.expanded {
  display: block;
}

.nav-children .nav-item {
  padding-left: 48px;
  font-size: 13px;
}

.nav-toggle {
  margin-left: auto;
  transition: transform 0.2s;
}

.nav-toggle.expanded {
  transform: rotate(90deg);
}

/* Main Content */
.main-content {
  margin-left: var(--sidebar-width);
  flex: 1;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  height: var(--header-height);
  background: white;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 16px;
}

.header-left .breadcrumb {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--gray-500);
}

.breadcrumb a {
  color: var(--gray-500);
}

.breadcrumb a:hover {
  color: var(--primary);
}

.breadcrumb .current {
  color: var(--gray-800);
  font-weight: 500;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.header-search {
  position: relative;
}

.header-search input {
  width: 240px;
  padding: 6px 12px 6px 32px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  font-size: 13px;
  background: var(--gray-50);
  outline: none;
  transition: var(--transition);
}

.header-search input:focus {
  border-color: var(--primary);
  background: white;
  width: 300px;
}

.header-search .search-icon {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--gray-400);
  font-size: 13px;
}

.header-user {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  padding: 4px 8px;
  border-radius: var(--border-radius);
  transition: var(--transition);
}

.header-user:hover {
  background: var(--gray-100);
}

.header-user .avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--primary);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 600;
}

.header-user .user-info {
  line-height: 1.3;
}

.header-user .user-name {
  font-size: 13px;
  font-weight: 500;
}

.header-user .user-role {
  font-size: 11px;
  color: var(--gray-500);
}

/* Page Content */
.page-content {
  padding: 24px;
  flex: 1;
}

.page-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 24px;
}

.page-header h1 {
  font-size: 22px;
  font-weight: 700;
  color: var(--gray-900);
}

.page-header p {
  font-size: 14px;
  color: var(--gray-500);
  margin-top: 4px;
}

.page-actions {
  display: flex;
  gap: 8px;
}

/* ============================================
   Cards
   ============================================ */
.card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius-lg);
  overflow: hidden;
}

.card-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.card-header h3 {
  font-size: 15px;
  font-weight: 600;
}

.card-body {
  padding: 20px;
}

.card-footer {
  padding: 12px 20px;
  border-top: 1px solid var(--gray-200);
  background: var(--gray-50);
}

/* Stat Cards */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
  margin-bottom: 24px;
}

.stat-card {
  background: white;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius-lg);
  padding: 20px;
  transition: var(--transition);
}

.stat-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.stat-card .stat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}

.stat-card .stat-icon {
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
}

.stat-card .stat-icon.blue { background: var(--primary-bg); color: var(--primary); }
.stat-card .stat-icon.green { background: var(--success-bg); color: var(--success); }
.stat-card .stat-icon.yellow { background: var(--warning-bg); color: var(--warning); }
.stat-card .stat-icon.red { background: var(--danger-bg); color: var(--danger); }
.stat-card .stat-icon.purple { background: var(--info-bg); color: var(--info); }

.stat-card .stat-label {
  font-size: 13px;
  color: var(--gray-500);
}

.stat-card .stat-value {
  font-size: 28px;
  font-weight: 700;
  color: var(--gray-900);
  line-height: 1.2;
}

.stat-card .stat-change {
  font-size: 12px;
  margin-top: 4px;
}

.stat-card .stat-change.up { color: var(--success); }
.stat-card .stat-change.down { color: var(--danger); }

/* ============================================
   Tables
   ============================================ */
.table-container {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
}

table th {
  text-align: left;
  padding: 10px 16px;
  font-size: 12px;
  font-weight: 600;
  color: var(--gray-500);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: var(--gray-50);
  border-bottom: 1px solid var(--gray-200);
  white-space: nowrap;
}

table td {
  padding: 12px 16px;
  font-size: 13px;
  border-bottom: 1px solid var(--gray-100);
  vertical-align: middle;
}

table tr:hover td {
  background: var(--gray-50);
}

table tr:last-child td {
  border-bottom: none;
}

/* ============================================
   Forms
   ============================================ */
.form-group {
  margin-bottom: 16px;
}

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--gray-700);
  margin-bottom: 6px;
}

.form-label .required {
  color: var(--danger);
  margin-left: 2px;
}

.form-input,
.form-select,
.form-textarea {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 14px;
  font-family: inherit;
  transition: var(--transition);
  outline: none;
  background: white;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-textarea {
  resize: vertical;
  min-height: 80px;
}

.form-hint {
  font-size: 12px;
  color: var(--gray-500);
  margin-top: 4px;
}

.form-row {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 16px;
}

/* Checkbox & Radio */
.form-check {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
}

.form-check input[type="checkbox"],
.form-check input[type="radio"] {
  accent-color: var(--primary);
}

/* Toggle Switch */
.toggle {
  position: relative;
  display: inline-block;
  width: 44px;
  height: 24px;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--gray-300);
  border-radius: 12px;
  transition: var(--transition);
}

.toggle-slider::before {
  content: "";
  position: absolute;
  width: 18px;
  height: 18px;
  left: 3px;
  bottom: 3px;
  background: white;
  border-radius: 50%;
  transition: var(--transition);
}

.toggle input:checked + .toggle-slider {
  background: var(--primary);
}

.toggle input:checked + .toggle-slider::before {
  transform: translateX(20px);
}

/* ============================================
   Badges & Tags
   ============================================ */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 12px;
  font-weight: 500;
}

.badge-primary { background: var(--primary-bg); color: var(--primary); }
.badge-success { background: var(--success-bg); color: var(--success); }
.badge-warning { background: var(--warning-bg); color: var(--warning); }
.badge-info { background: var(--info-bg); color: var(--info); }
.badge-danger { background: var(--danger-bg); color: var(--danger); }
.badge-gray { background: var(--gray-100); color: var(--gray-600); }

.tag {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 10px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius-sm);
  font-size: 12px;
  color: var(--gray-600);
  background: white;
}

.tag-remove {
  cursor: pointer;
  color: var(--gray-400);
  font-size: 14px;
  line-height: 1;
}

.tag-remove:hover {
  color: var(--danger);
}

/* ============================================
   Tabs
   ============================================ */
.tabs {
  display: flex;
  border-bottom: 1px solid var(--gray-200);
  gap: 0;
  margin-bottom: 20px;
}

.tab-item {
  padding: 10px 20px;
  font-size: 14px;
  color: var(--gray-500);
  cursor: pointer;
  border-bottom: 2px solid transparent;
  transition: var(--transition);
}

.tab-item:hover {
  color: var(--gray-700);
}

.tab-item.active {
  color: var(--primary);
  border-bottom-color: var(--primary);
  font-weight: 500;
}

/* ============================================
   Status Indicators
   ============================================ */
.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  margin-right: 6px;
}

.status-dot.online { background: var(--success); }
.status-dot.offline { background: var(--gray-400); }
.status-dot.warning { background: var(--warning); }
.status-dot.error { background: var(--danger); }

/* Progress Bar */
.progress {
  height: 6px;
  background: var(--gray-200);
  border-radius: 3px;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  border-radius: 3px;
  transition: width 0.3s ease;
}

.progress-bar.blue { background: var(--primary); }
.progress-bar.green { background: var(--success); }
.progress-bar.yellow { background: var(--warning); }
.progress-bar.red { background: var(--danger); }

/* ============================================
   Modal / Dialog
   ============================================ */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
}

.modal {
  background: white;
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  width: 90%;
  max-width: 560px;
  max-height: 90vh;
  overflow-y: auto;
  transform: translateY(20px);
  transition: var(--transition);
}

.modal-overlay.active .modal {
  transform: translateY(0);
}

.modal-header {
  padding: 20px 24px;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-header h3 {
  font-size: 16px;
  font-weight: 600;
}

.modal-close {
  background: none;
  border: none;
  font-size: 20px;
  color: var(--gray-400);
  cursor: pointer;
  padding: 4px;
}

.modal-close:hover {
  color: var(--gray-600);
}

.modal-body {
  padding: 24px;
}

.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--gray-200);
  display: flex;
  justify-content: flex-end;
  gap: 8px;
}

.modal-fixed {
  display: flex;
  flex-direction: column;
  max-height: 86vh;
  overflow: hidden;
}

.modal-fixed .modal-header,
.modal-fixed .modal-footer {
  flex-shrink: 0;
  background: white;
  z-index: 1;
}

.modal-fixed .modal-body {
  flex: 1;
  overflow-y: auto;
  min-height: 0;
}

/* Paper Wizard */
.paper-wizard-modal {
  max-width: 980px;
}

.learning-task-modal {
  max-width: 980px;
}

.paper-wizard-modal .modal-body {
  padding: 20px 24px 24px;
}

.paper-wizard-steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin-bottom: 20px;
}

.learning-task-steps {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.wizard-step-btn {
  justify-content: center;
}

.paper-wizard-step {
  min-height: 420px;
}

.step-section-title {
  margin-bottom: 16px;
}

.step-section-title h4 {
  font-size: 16px;
  color: var(--gray-900);
  margin-bottom: 6px;
}

.step-section-title p {
  font-size: 13px;
  color: var(--gray-500);
}

.form-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.form-grid .form-group.full {
  grid-column: 1 / -1;
}

.filter-row {
  display: grid;
  grid-template-columns: 160px 160px 160px 1fr auto;
  gap: 12px;
  align-items: center;
  margin-bottom: 16px;
  padding: 14px;
  background: var(--gray-50);
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
}

.question-picker-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(300px, 0.55fr);
  gap: 16px;
}

.question-bank-panel,
.selected-question-panel {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
  overflow: hidden;
}

.panel-title-row,
.space-between {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.panel-title-row {
  padding: 12px 14px;
  border-bottom: 1px solid var(--gray-200);
  background: var(--gray-50);
}

.table-wrap {
  overflow-x: auto;
}

.question-bank-filter {
  grid-template-columns: 150px 150px 1fr auto;
}

.selected-question-list {
  padding: 12px;
  display: grid;
  gap: 14px;
}

.selected-question-summary {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  flex-wrap: wrap;
  gap: 8px;
}

.selected-question-group {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
  overflow: hidden;
}

.selected-question-group-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  background: var(--primary-bg);
  border-bottom: 1px solid var(--gray-200);
}

.selected-question-group-head strong {
  display: block;
  color: var(--gray-900);
  font-size: 14px;
}

.selected-question-group-head span:not(.badge) {
  display: block;
  margin-top: 3px;
  color: var(--gray-500);
  font-size: 12px;
}

.selected-question-group-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

.selected-question-group-body {
  display: grid;
  gap: 8px;
  padding: 10px;
}

.selected-question-item {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  padding: 10px 12px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: var(--gray-50);
}

.selected-question-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  justify-content: flex-end;
}

.selected-question-item strong {
  display: block;
  margin-bottom: 4px;
  color: var(--gray-900);
}

.selected-question-item span {
  font-size: 12px;
  color: var(--gray-500);
}

.drag-handle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 56px;
  height: 28px;
  padding: 0 8px;
  border: 1px dashed var(--gray-300);
  border-radius: var(--border-radius-sm);
  background: white;
  color: var(--gray-500);
  font-size: 12px;
  cursor: grab;
  user-select: none;
}

.drag-handle:active {
  cursor: grabbing;
}

.draggable-group-head {
  grid-template-columns: auto 1fr auto;
}

.selected-question-item.draggable-question {
  grid-template-columns: auto 1fr auto;
  align-items: center;
}

.selected-question-group.dragging,
.selected-question-item.dragging {
  opacity: 0.45;
}

.selected-question-group.drag-over,
.selected-question-item.drag-over {
  outline: 2px dashed var(--primary);
  outline-offset: 2px;
  background: var(--primary-bg);
}

.paper-group-list {
  display: grid;
  gap: 12px;
}

.paper-group-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
  padding: 14px;
}

.paper-group-card .group-form-row {
  display: grid;
  grid-template-columns: 1.25fr 1fr 110px 110px 1fr;
  gap: 12px;
  align-items: end;
}

.paper-group-card .group-summary {
  padding: 8px 10px;
  background: var(--primary-bg);
  color: var(--primary);
  border-radius: var(--border-radius);
  font-size: 13px;
  font-weight: 500;
}

.preview-paper-card {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  overflow: hidden;
  background: white;
}

.preview-paper-head {
  padding: 16px;
  border-bottom: 1px solid var(--gray-200);
  background: var(--gray-50);
}

.preview-paper-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}

.preview-question-table {
  padding: 14px 16px 16px;
}

.paper-view-metrics {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.paper-view-metric {
  padding: 14px 16px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: var(--gray-50);
}

.paper-view-metric span {
  display: block;
  margin-bottom: 6px;
  color: var(--gray-500);
  font-size: 13px;
}

.paper-view-metric strong {
  color: var(--gray-900);
  font-size: 18px;
}

.paper-view-groups {
  display: grid;
  gap: 14px;
}

.paper-view-group {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  overflow: hidden;
}

.paper-view-group-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 14px;
  background: var(--primary-bg);
  border-bottom: 1px solid var(--gray-200);
}

.paper-view-group-head h4 {
  margin-bottom: 3px;
  color: var(--gray-900);
  font-size: 15px;
}

.paper-view-group-head p {
  color: var(--gray-500);
  font-size: 12px;
}

.paper-view-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--gray-100);
  background: white;
}

.paper-view-question:last-child {
  border-bottom: 0;
}

.paper-view-question strong {
  display: block;
  margin-bottom: 4px;
  color: var(--gray-900);
}

.paper-view-question span:not(.badge) {
  color: var(--gray-600);
  font-size: 13px;
}

.paper-check-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
}

.paper-check-list > div {
  padding: 14px 16px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: var(--success-bg);
}

.paper-check-list span {
  display: block;
  margin-bottom: 6px;
  color: var(--gray-600);
  font-size: 13px;
}

.paper-check-list strong {
  color: var(--success);
}

.candidate-scope-panel {
  display: grid;
  gap: 14px;
  padding: 14px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: var(--gray-50);
}

.candidate-mode-row,
.candidate-operation-row {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
}

.candidate-condition-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.candidate-add-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 128px minmax(0, 1fr);
  gap: 12px;
  align-items: stretch;
}

.candidate-add-actions {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: center;
  gap: 8px;
}

.candidate-mode-panel {
  display: none;
}

.candidate-mode-panel.active {
  display: block;
}

.candidate-search-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
  margin-bottom: 8px;
}

.candidate-condition-card {
  padding: 12px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
}

.candidate-condition-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 8px;
  margin-bottom: 10px;
}

.candidate-condition-card select {
  min-height: 132px;
}

.candidate-rule-summary {
  padding: 12px 14px;
  border: 1px solid var(--primary-light);
  border-radius: var(--border-radius);
  background: var(--primary-bg);
  color: var(--gray-700);
  font-size: 13px;
}

.candidate-rule-summary span {
  display: block;
  margin-top: 4px;
  color: var(--primary);
  font-weight: 600;
}

.candidate-result-table {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
  overflow: hidden;
}

.candidate-result-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  border-bottom: 1px solid var(--gray-200);
  background: white;
}

.candidate-result-head h4 {
  font-size: 14px;
  color: var(--gray-900);
}

.learning-question-picker {
  display: grid;
  gap: 14px;
  padding: 14px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: var(--gray-50);
}

.learning-filter-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.learning-filter-grid .form-group {
  margin-bottom: 0;
}

.learning-picker-actions {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 12px 14px;
  border: 1px solid var(--primary-light);
  border-radius: var(--border-radius);
  background: var(--primary-bg);
}

.learning-picker-actions strong {
  display: block;
  color: var(--primary);
  font-size: 15px;
}

.learning-selected-table {
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: white;
  overflow: hidden;
}

.learning-selected-table table {
  min-width: 680px;
}

.learning-selected-table .pagination {
  padding: 12px 14px;
  border-top: 1px solid var(--gray-100);
  background: white;
}

.learning-result-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-wrap: wrap;
}

.learning-question-title {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.learning-selected-empty {
  padding: 24px;
  color: var(--gray-500);
  text-align: center;
}

@media (max-width: 1280px) {
  .filter-row,
  .question-picker-layout,
  .paper-group-card .group-form-row,
  .paper-view-metrics,
  .paper-check-list,
  .candidate-condition-grid,
  .candidate-add-layout,
  .learning-filter-grid {
    grid-template-columns: 1fr;
  }

  .candidate-add-actions {
    flex-direction: row;
    flex-wrap: wrap;
  }
}

/* ============================================
   Empty State
   ============================================ */
.empty-state {
  text-align: center;
  padding: 60px 20px;
  color: var(--gray-500);
}

.empty-state .empty-icon {
  font-size: 48px;
  margin-bottom: 16px;
  opacity: 0.5;
}

.empty-state h3 {
  font-size: 16px;
  color: var(--gray-700);
  margin-bottom: 8px;
}

.empty-state p {
  font-size: 14px;
  margin-bottom: 20px;
}

/* ============================================
   Filter Bar
   ============================================ */
.filter-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
  flex-wrap: wrap;
}

.filter-bar .search-box {
  position: relative;
  flex: 1;
  min-width: 200px;
  max-width: 320px;
}

.filter-bar .search-box input {
  width: 100%;
  padding: 7px 12px 7px 32px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 13px;
  outline: none;
}

.filter-bar .search-box input:focus {
  border-color: var(--primary);
}

.filter-bar .search-box .search-icon {
  position: absolute;
  left: 10px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--gray-400);
}

.filter-bar select {
  padding: 7px 28px 7px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 13px;
  background: white;
  outline: none;
  cursor: pointer;
}

/* ============================================
   Dify-style AI Components
   ============================================ */
.dify-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 0;
  height: calc(100vh - var(--header-height));
  overflow: hidden;
}

.dify-sidebar {
  background: white;
  border-right: 1px solid var(--gray-200);
  overflow-y: auto;
  padding: 16px;
}

.dify-sidebar-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--gray-500);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 12px;
  padding: 0 4px;
}

.dify-nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: var(--border-radius);
  font-size: 13px;
  color: var(--gray-600);
  cursor: pointer;
  transition: var(--transition);
  margin-bottom: 2px;
}

.dify-nav-item:hover {
  background: var(--gray-100);
}

.dify-nav-item.active {
  background: var(--primary-bg);
  color: var(--primary);
  font-weight: 500;
}

.dify-nav-item .item-icon {
  width: 20px;
  text-align: center;
}

.dify-main {
  overflow-y: auto;
  padding: 24px;
  background: var(--gray-50);
}

/* Chat Interface */
.chat-container {
  display: flex;
  flex-direction: column;
  height: 100%;
  background: white;
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--gray-200);
  overflow: hidden;
}

.chat-header {
  padding: 12px 20px;
  border-bottom: 1px solid var(--gray-200);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
}

.chat-message {
  margin-bottom: 20px;
  display: flex;
  gap: 12px;
}

.chat-message.user {
  flex-direction: row-reverse;
}

.chat-message .msg-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 600;
}

.chat-message.assistant .msg-avatar {
  background: var(--primary-bg);
  color: var(--primary);
}

.chat-message.user .msg-avatar {
  background: var(--gray-200);
  color: var(--gray-600);
}

.chat-message .msg-content {
  max-width: 70%;
}

.chat-message .msg-bubble {
  padding: 12px 16px;
  border-radius: var(--border-radius-lg);
  font-size: 14px;
  line-height: 1.6;
}

.chat-message.assistant .msg-bubble {
  background: var(--gray-100);
  border-top-left-radius: 4px;
}

.chat-message.user .msg-bubble {
  background: var(--primary);
  color: white;
  border-top-right-radius: 4px;
}

.chat-message .msg-source {
  margin-top: 8px;
  padding: 8px 12px;
  background: var(--primary-bg);
  border-radius: var(--border-radius);
  font-size: 12px;
  color: var(--gray-600);
}

.chat-input {
  padding: 16px 20px;
  border-top: 1px solid var(--gray-200);
  display: flex;
  gap: 8px;
}

.chat-input textarea {
  flex: 1;
  padding: 10px 12px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius);
  font-size: 14px;
  font-family: inherit;
  resize: none;
  outline: none;
  min-height: 42px;
  max-height: 120px;
}

.chat-input textarea:focus {
  border-color: var(--primary);
}

/* ============================================
   Utility Classes
   ============================================ */
.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-2 { gap: 8px; }
.gap-3 { gap: 12px; }
.gap-4 { gap: 16px; }
.mt-2 { margin-top: 8px; }
.mt-4 { margin-top: 16px; }
.mb-2 { margin-bottom: 8px; }
.mb-4 { margin-bottom: 16px; }
.p-4 { padding: 16px; }
.text-sm { font-size: 13px; }
.text-xs { font-size: 12px; }
.text-gray { color: var(--gray-500); }
.text-center { text-align: center; }
.font-medium { font-weight: 500; }
.font-bold { font-weight: 700; }
.w-full { width: 100%; }

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
  .sidebar {
    transform: translateX(-100%);
  }
  .main-content {
    margin-left: 0;
  }
  .dify-layout {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   Pagination
   ============================================ */
.pagination {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 0;
  font-size: 13px;
  color: var(--gray-500);
}

.pagination .page-info {
  font-size: 13px;
}

.pagination .page-buttons {
  display: flex;
  gap: 4px;
}

.pagination .page-btn {
  padding: 4px 10px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius-sm);
  background: white;
  cursor: pointer;
  font-size: 13px;
  transition: var(--transition);
}

.pagination .page-btn:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.pagination .page-btn.active {
  background: var(--primary);
  border-color: var(--primary);
  color: white;
}

.pagination .page-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* ============================================
   Slider Control
   ============================================ */
.slider-group {
  display: flex;
  align-items: center;
  gap: 12px;
}

.slider-group input[type="range"] {
  flex: 1;
  height: 4px;
  -webkit-appearance: none;
  background: var(--gray-200);
  border-radius: 2px;
  outline: none;
}

.slider-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  background: var(--primary);
  border-radius: 50%;
  cursor: pointer;
}

.slider-value {
  min-width: 48px;
  text-align: center;
  font-size: 14px;
  font-weight: 600;
  color: var(--primary);
}

/* ============================================
   Tree View
   ============================================ */
.tree-node {
  padding-left: 20px;
}

.tree-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-radius: var(--border-radius-sm);
  cursor: pointer;
  transition: var(--transition);
  font-size: 13px;
}

.tree-item:hover {
  background: var(--gray-100);
}

.tree-item .tree-icon {
  color: var(--gray-400);
  font-size: 12px;
  transition: transform 0.2s;
}

.tree-item .tree-icon.expanded {
  transform: rotate(90deg);
}

.tree-item .folder-icon {
  color: var(--warning);
}

/* ============================================
   Timeline / Log
   ============================================ */
.timeline-item {
  display: flex;
  gap: 16px;
  padding-bottom: 20px;
  position: relative;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 15px;
  top: 32px;
  bottom: 0;
  width: 2px;
  background: var(--gray-200);
}

.timeline-item:last-child::before {
  display: none;
}

.timeline-dot {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--primary-bg);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  flex-shrink: 0;
  z-index: 1;
}

.timeline-content {
  flex: 1;
}

.timeline-content h4 {
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 4px;
}

.timeline-content p {
  font-size: 13px;
  color: var(--gray-500);
}

/* ============================================
   Tooltip
   ============================================ */
.tooltip {
  position: relative;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--gray-800);
  color: white;
  padding: 4px 10px;
  border-radius: var(--border-radius-sm);
  font-size: 12px;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: var(--transition);
  pointer-events: none;
}

.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
}

/* ============================================
   Chart Placeholder
   ============================================ */
.chart-placeholder {
  height: 200px;
  background: linear-gradient(135deg, var(--gray-50) 0%, var(--gray-100) 100%);
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--gray-400);
  font-size: 14px;
}

/* ============================================
   Drag & Drop Zone
   ============================================ */
.upload-zone {
  border: 2px dashed var(--gray-300);
  border-radius: var(--border-radius-lg);
  padding: 40px;
  text-align: center;
  cursor: pointer;
  transition: var(--transition);
}

.upload-zone:hover {
  border-color: var(--primary);
  background: var(--primary-bg);
}

.upload-zone .upload-icon {
  font-size: 36px;
  color: var(--gray-400);
  margin-bottom: 12px;
}

.upload-zone p {
  color: var(--gray-500);
  font-size: 14px;
}

.upload-zone .upload-hint {
  font-size: 12px;
  color: var(--gray-400);
  margin-top: 4px;
}

/* 人工阅卷 */
.grading-workspace {
  display: grid;
  grid-template-columns: minmax(270px, 300px) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}

.manual-grading-filter {
  margin-bottom: 0;
}

.manual-grading-filter .search-box {
  min-width: 260px;
  flex: 1;
}

.grading-queue-card,
.grading-paper-card {
  min-width: 0;
}

.grading-queue-summary {
  padding: 12px 16px;
  border-bottom: 1px solid var(--gray-200);
  color: var(--gray-500);
  font-size: var(--font-size-sm);
}

.grading-queue-summary em {
  display: block;
  height: 6px;
  margin-top: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: var(--gray-100);
}

.grading-queue-summary i {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--primary);
}

.grading-candidate-list {
  padding: 8px;
}

.grading-candidate {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr) auto;
  width: 100%;
  align-items: center;
  gap: 10px;
  padding: 10px 8px;
  border: 1px solid transparent;
  border-radius: var(--border-radius);
  background: transparent;
  color: inherit;
  cursor: pointer;
  text-align: left;
}

.grading-candidate:hover {
  background: var(--gray-50);
}

.grading-candidate.active {
  border-color: #bfdbfe;
  background: var(--primary-bg);
}

.grading-candidate-avatar {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 50%;
  background: #dbeafe;
  color: var(--primary-dark);
  font-size: 13px;
  font-weight: 700;
}

.grading-candidate.done .grading-candidate-avatar {
  background: var(--success-bg);
  color: #059669;
}

.grading-candidate-copy {
  min-width: 0;
}

.grading-candidate-copy strong,
.grading-candidate-copy em {
  display: block;
}

.grading-candidate-copy strong {
  color: var(--gray-800);
  font-size: 13px;
}

.grading-candidate-copy em {
  overflow: hidden;
  color: var(--gray-500);
  font-size: 12px;
  font-style: normal;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.grading-paper-header {
  align-items: center;
}

.grading-paper-body {
  padding: 16px;
}

.grading-score-summary {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-bottom: 16px;
  overflow: hidden;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
}

.grading-score-summary > div {
  padding: 12px 14px;
  border-right: 1px solid var(--gray-200);
}

.grading-score-summary > div:last-child {
  border-right: 0;
  background: var(--primary-bg);
}

.grading-score-summary span,
.grading-score-summary strong {
  display: block;
}

.grading-score-summary span {
  color: var(--gray-500);
  font-size: 12px;
}

.grading-score-summary strong {
  margin-top: 2px;
  color: var(--gray-800);
  font-size: 20px;
}

.grading-question {
  padding: 16px;
  border: 1px solid var(--gray-200);
  border-radius: var(--border-radius);
  background: #fff;
}

.grading-question + .grading-question {
  margin-top: 14px;
}

.grading-question-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

.grading-question-head > div {
  display: flex;
  align-items: center;
  gap: 8px;
}

.grading-question h4 {
  margin: 14px 0 10px;
  color: var(--gray-800);
  font-size: 15px;
}

.grading-answer-block {
  padding: 12px;
  border-left: 3px solid #93c5fd;
  border-radius: 0 var(--border-radius-sm) var(--border-radius-sm) 0;
  background: var(--gray-50);
}

.grading-answer-block span {
  display: block;
  margin-bottom: 4px;
  color: var(--gray-500);
  font-size: 12px;
}

.grading-answer-block p {
  color: var(--gray-700);
  font-size: 13px;
}

.grading-reference {
  margin-top: 10px;
  color: var(--gray-600);
  font-size: 13px;
}

.grading-reference summary {
  color: var(--primary);
  cursor: pointer;
}

.grading-reference p {
  margin-top: 8px;
  padding: 10px 12px;
  border-radius: var(--border-radius-sm);
  background: var(--warning-bg);
}

.grading-score-input {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--gray-600);
  font-size: 13px;
}

.grading-score-input input {
  width: 54px;
  padding: 6px 8px;
  border: 1px solid var(--gray-300);
  border-radius: var(--border-radius-sm);
  color: var(--gray-800);
  font: inherit;
  text-align: center;
}

.grading-score-input em {
  color: var(--gray-500);
  font-size: 12px;
  font-style: normal;
}

.grading-action-bar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 16px;
  padding: 14px 16px;
  border-top: 1px solid var(--gray-200);
  background: var(--gray-50);
}

@media (max-width: 1080px) {
  .grading-workspace {
    grid-template-columns: 1fr;
  }
}