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

:root {
  --primary: #0d9488;
  --primary-light: #14b8a6;
  --primary-dark: #0f766e;
  --primary-bg: #f0fdfa;
  --bg: #ffffff;
  --bg-secondary: #f8fafb;
  --bg-sidebar: #f1f5f4;
  --text: #1a1a2e;
  --text-secondary: #64748b;
  --border: #e2e8f0;
  --error: #ef4444;
  --code-bg: #1e293b;
  --shadow: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-lg: 0 4px 12px rgba(0,0,0,0.1);
  --radius: 10px;
  --radius-sm: 6px;
  --sidebar-width: 280px;
}

html, body {
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  font-size: 15px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg);
}

/* ============ Login Page ============ */
.login-body {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  background: linear-gradient(135deg, #f0fdfa 0%, #e0f2fe 50%, #f0fdfa 100%);
}

.login-container {
  width: 100%;
  max-width: 420px;
  padding: 20px;
}

.login-card {
  background: var(--bg);
  border-radius: 16px;
  padding: 40px 36px 36px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
}

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

.login-logo svg {
  margin-bottom: 12px;
}

.login-logo h1 {
  font-size: 24px;
  font-weight: 700;
  color: var(--text);
}

.login-subtitle {
  font-size: 13px;
  color: var(--text-secondary);
  margin-top: 4px;
}

.form-group {
  margin-bottom: 18px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 600;
  color: var(--text);
  margin-bottom: 6px;
}

.form-group input {
  width: 100%;
  padding: 10px 14px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 15px;
  transition: border-color 0.2s, box-shadow 0.2s;
  outline: none;
  background: var(--bg);
}

.form-group input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.12);
}

.error-msg {
  color: var(--error);
  font-size: 13px;
  margin-bottom: 12px;
  text-align: center;
}

.btn-primary {
  width: 100%;
  padding: 11px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

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

.btn-primary:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.login-footer {
  text-align: center;
  margin-top: 20px;
  font-size: 13px;
  color: var(--text-secondary);
}

/* ============ Chat Layout ============ */
.chat-body {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-width);
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  transition: transform 0.3s ease, margin-left 0.3s ease;
}

.sidebar.collapsed {
  margin-left: calc(-1 * var(--sidebar-width));
}

.sidebar-header {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 16px 18px;
  font-weight: 700;
  font-size: 16px;
  color: var(--text);
  border-bottom: 1px solid var(--border);
}

.new-chat-btn {
  margin: 12px 14px 8px;
  padding: 10px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.2s;
}

.new-chat-btn:hover {
  background: var(--primary-dark);
}

.chat-history {
  flex: 1;
  overflow-y: auto;
  padding: 8px 10px;
}

.chat-history-item {
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  color: var(--text);
  cursor: pointer;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 6px;
  margin-bottom: 2px;
}

.chat-history-item:hover {
  background: rgba(13, 148, 136, 0.08);
}

.chat-history-item.active {
  background: rgba(13, 148, 136, 0.12);
  font-weight: 600;
}

.chat-history-item .delete-chat {
  display: none;
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 2px 4px;
  font-size: 14px;
  flex-shrink: 0;
}

.chat-history-item:hover .delete-chat {
  display: inline-block;
}

.chat-history-item .delete-chat:hover {
  color: var(--error);
}

.sidebar-footer {
  padding: 14px 18px;
  border-top: 1px solid var(--border);
}

.user-info {
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 8px;
}

.logout-btn {
  width: 100%;
  padding: 8px;
  background: transparent;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.2s;
}

.logout-btn:hover {
  border-color: var(--error);
  color: var(--error);
}

/* Main Chat */
.chat-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.chat-header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  background: var(--bg);
}

.chat-header h2 {
  font-size: 16px;
  font-weight: 600;
  flex: 1;
}

.header-username {
  font-size: 13px;
  color: var(--text-secondary);
}

.toggle-sidebar-btn {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text-secondary);
  padding: 4px;
  border-radius: 4px;
  display: flex;
  align-items: center;
}

.toggle-sidebar-btn:hover {
  background: var(--bg-secondary);
}

/* Messages */
.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px 0;
}

.welcome-screen {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100%;
  padding: 40px 20px;
  text-align: center;
}

.welcome-icon {
  margin-bottom: 20px;
}

.welcome-screen h2 {
  font-size: 22px;
  margin-bottom: 8px;
  color: var(--text);
}

.welcome-screen p {
  color: var(--text-secondary);
  max-width: 480px;
  font-size: 14px;
  margin-bottom: 28px;
}

.welcome-suggestions {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
  max-width: 480px;
  width: 100%;
}

.suggestion-btn {
  padding: 14px 16px;
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  font-size: 13px;
  color: var(--text);
  cursor: pointer;
  text-align: left;
  transition: all 0.2s;
}

.suggestion-btn:hover {
  border-color: var(--primary);
  background: var(--primary-bg);
}

/* Message Bubbles */
.message {
  max-width: 780px;
  margin: 0 auto;
  padding: 8px 24px;
  display: flex;
  gap: 14px;
}

.message-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 14px;
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 2px;
}

.message.user .message-avatar {
  background: var(--primary);
  color: #fff;
}

.message.assistant .message-avatar {
  background: var(--primary-bg);
  color: var(--primary);
  border: 1.5px solid var(--primary);
}

.message-content {
  flex: 1;
  min-width: 0;
  font-size: 15px;
  line-height: 1.7;
}

.message.user .message-content {
  background: var(--primary-bg);
  padding: 12px 16px;
  border-radius: var(--radius);
  border-top-left-radius: 2px;
}

.message.assistant .message-content {
  padding: 4px 0;
}

/* Markdown content */
.message-content p {
  margin-bottom: 10px;
}

.message-content p:last-child {
  margin-bottom: 0;
}

.message-content ul, .message-content ol {
  margin: 8px 0;
  padding-left: 24px;
}

.message-content li {
  margin-bottom: 4px;
}

.message-content h1, .message-content h2, .message-content h3,
.message-content h4, .message-content h5, .message-content h6 {
  margin: 16px 0 8px;
  font-weight: 600;
}

.message-content h1 { font-size: 1.3em; }
.message-content h2 { font-size: 1.2em; }
.message-content h3 { font-size: 1.1em; }

.message-content blockquote {
  border-left: 3px solid var(--primary);
  padding: 4px 14px;
  margin: 8px 0;
  color: var(--text-secondary);
  background: var(--bg-secondary);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

.message-content table {
  border-collapse: collapse;
  margin: 10px 0;
  width: 100%;
  font-size: 14px;
}

.message-content th, .message-content td {
  border: 1px solid var(--border);
  padding: 8px 12px;
  text-align: left;
}

.message-content th {
  background: var(--bg-secondary);
  font-weight: 600;
}

/* Code blocks */
.message-content code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  font-size: 0.9em;
}

.message-content :not(pre) > code {
  background: #e8ecef;
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--primary-dark);
}

.code-block-wrapper {
  position: relative;
  margin: 10px 0;
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.code-block-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: #151b28;
  padding: 6px 14px;
  font-size: 12px;
  color: #94a3b8;
}

.copy-btn {
  background: none;
  border: none;
  color: #94a3b8;
  cursor: pointer;
  font-size: 12px;
  padding: 2px 8px;
  border-radius: 4px;
  transition: all 0.2s;
}

.copy-btn:hover {
  background: rgba(255,255,255,0.1);
  color: #e2e8f0;
}

.code-block-wrapper pre {
  margin: 0;
  padding: 14px;
  background: var(--code-bg);
  overflow-x: auto;
}

.code-block-wrapper pre code {
  font-size: 13px;
  line-height: 1.5;
}

/* Typing indicator */
.typing-indicator {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 4px 0;
}

.typing-indicator span {
  width: 6px;
  height: 6px;
  background: var(--primary);
  border-radius: 50%;
  animation: blink 1.4s infinite;
}

.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes blink {
  0%, 100% { opacity: 0.3; }
  50% { opacity: 1; }
}

/* Input Area */
.chat-input-area {
  padding: 12px 24px 16px;
  border-top: 1px solid var(--border);
  background: var(--bg);
}

.input-wrapper {
  max-width: 780px;
  margin: 0 auto;
  display: flex;
  align-items: flex-end;
  gap: 8px;
  background: var(--bg);
  border: 1.5px solid var(--border);
  border-radius: 12px;
  padding: 8px 12px;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.input-wrapper:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.10);
}

#chatInput {
  flex: 1;
  border: none;
  outline: none;
  resize: none;
  font-size: 15px;
  font-family: inherit;
  line-height: 1.5;
  max-height: 150px;
  background: transparent;
  color: var(--text);
}

#chatInput::placeholder {
  color: var(--text-secondary);
}

.send-btn {
  width: 36px;
  height: 36px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
  flex-shrink: 0;
}

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

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

.input-hint {
  text-align: center;
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 6px;
  max-width: 780px;
  margin-left: auto;
  margin-right: auto;
}

/* ============ Responsive ============ */
@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    z-index: 100;
    transform: translateX(0);
  }

  .sidebar.collapsed {
    transform: translateX(-100%);
    margin-left: 0;
  }

  .sidebar-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.3);
    z-index: 99;
  }

  .welcome-suggestions {
    grid-template-columns: 1fr;
  }

  .message {
    padding: 8px 14px;
  }

  .chat-input-area {
    padding: 10px 14px 14px;
  }

  .chat-header {
    padding: 12px 14px;
  }
}

/* ============ Scrollbar ============ */
::-webkit-scrollbar {
  width: 6px;
}

::-webkit-scrollbar-track {
  background: transparent;
}

::-webkit-scrollbar-thumb {
  background: #c1c9d2;
  border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
  background: #a0aab4;
}

/* ============ Stop button ============ */
.stop-btn {
  width: 36px;
  height: 36px;
  background: var(--error);
  color: #fff;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.stop-btn:hover {
  opacity: 0.85;
}

/* ============ Dashboard Page ============ */
.dashboard-body {
  min-height: 100vh;
  background: linear-gradient(135deg, #f0fdfa 0%, #e0f2fe 50%, #f0fdfa 100%);
  display: flex;
  flex-direction: column;
}

/* Navigation */
.dashboard-nav {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.7);
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.dashboard-nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 60px;
}

.dashboard-nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 16px;
  color: var(--text);
}

.dashboard-nav-user {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 13px;
  color: var(--text-secondary);
}

/* Hero */
.dashboard-main {
  flex: 1;
  max-width: 1100px;
  margin: 0 auto;
  padding: 48px 24px 60px;
  width: 100%;
}

.dashboard-hero {
  text-align: center;
  margin-bottom: 48px;
}

.dashboard-hero h1 {
  font-size: 28px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 8px;
}

.dashboard-hero p {
  font-size: 15px;
  color: var(--text-secondary);
}

/* Module Grid */
.module-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 20px;
}

/* Module Card Base */
.module-card {
  background: var(--bg);
  border-radius: 16px;
  padding: 32px 28px;
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow);
  position: relative;
  animation: cardFadeIn 0.4s ease both;
}

@keyframes cardFadeIn {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.module-card h3 {
  font-size: 17px;
  font-weight: 700;
  margin-bottom: 6px;
  color: var(--text);
}

.module-card p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Module Icon */
.module-icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 18px;
  background: var(--primary-bg);
}

/* Active Card */
.module-card.module-active {
  cursor: pointer;
  text-decoration: none;
  color: inherit;
  display: block;
  transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

.module-card.module-active:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(13, 148, 136, 0.15);
  border-color: var(--primary-light);
}

.module-enter {
  margin-top: 16px;
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
  transition: color 0.2s;
}

.module-card.module-active:hover .module-enter {
  color: var(--primary-dark);
}

/* Disabled Card */
.module-card.module-disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.module-card.module-disabled .module-icon {
  background: var(--bg-secondary);
}

.module-badge {
  position: absolute;
  top: 14px;
  right: 14px;
  background: var(--bg-secondary);
  color: var(--text-secondary);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  border: 1px solid var(--border);
}

/* Dashboard Footer */
.dashboard-footer {
  text-align: center;
  padding: 20px 24px;
  font-size: 13px;
  color: var(--text-secondary);
}

/* Back Button (chat page) */
.back-to-dashboard-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  padding: 4px;
  border-radius: 4px;
  text-decoration: none;
  transition: color 0.2s, background 0.2s;
}

.back-to-dashboard-btn:hover {
  color: var(--primary);
  background: var(--bg-secondary);
}

/* Dashboard Responsive */
@media (max-width: 768px) {
  .dashboard-main {
    padding: 28px 16px 40px;
  }

  .dashboard-hero {
    margin-bottom: 32px;
  }

  .dashboard-hero h1 {
    font-size: 22px;
  }

  .module-grid {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .module-card {
    padding: 24px 20px;
  }

  .dashboard-nav {
    padding: 0 16px;
  }
}

/* ============ Quiz Page ============ */
.quiz-body {
  min-height: 100vh;
  background: linear-gradient(135deg, #f0fdfa 0%, #e0f2fe 50%, #f0fdfa 100%);
  display: flex;
  flex-direction: column;
}

/* Quiz Nav */
.quiz-nav {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.7);
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.quiz-nav-inner {
  max-width: 720px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.quiz-back-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: color 0.2s, background 0.2s;
}

.quiz-back-btn:hover {
  color: var(--primary);
  background: rgba(13, 148, 136, 0.06);
}

.quiz-progress-area {
  display: flex;
  align-items: center;
  gap: 10px;
}

.quiz-progress-text {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
}

.quiz-progress-bar {
  width: 120px;
  height: 6px;
  background: var(--border);
  border-radius: 3px;
  overflow: hidden;
}

.quiz-progress-fill {
  height: 100%;
  background: var(--primary);
  border-radius: 3px;
  transition: width 0.35s ease;
  width: 0%;
}

/* Quiz Main */
.quiz-main {
  flex: 1;
  max-width: 720px;
  margin: 0 auto;
  padding: 32px 24px 60px;
  width: 100%;
}

/* Quiz Card */
.quiz-card {
  background: var(--bg);
  border-radius: 16px;
  padding: 36px 32px;
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow-lg);
  animation: cardFadeIn 0.35s ease both;
}

.quiz-question-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 700;
  padding: 3px 10px;
  border-radius: 20px;
  margin-bottom: 16px;
}

.quiz-question-tag.tag-single {
  background: #ecfdf5;
  color: #059669;
}

.quiz-question-tag.tag-multiple {
  background: #eff6ff;
  color: #2563eb;
}

.quiz-question-text {
  font-size: 17px;
  font-weight: 600;
  line-height: 1.6;
  color: var(--text);
  margin-bottom: 24px;
}

.quiz-question-text code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  font-size: 0.9em;
  background: #e8ecef;
  padding: 2px 6px;
  border-radius: 4px;
  color: var(--primary-dark);
}

/* Options */
.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 24px;
}

.quiz-option {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 14px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius);
  cursor: pointer;
  transition: all 0.2s ease;
  user-select: none;
  background: var(--bg);
}

.quiz-option:hover {
  border-color: var(--primary-light);
  background: var(--primary-bg);
}

.quiz-option.selected {
  border-color: var(--primary);
  background: var(--primary-bg);
}

.quiz-option.correct {
  border-color: #22c55e;
  background: #f0fdf4;
  cursor: default;
}

.quiz-option.incorrect {
  border-color: var(--error);
  background: #fef2f2;
  cursor: default;
}

.quiz-option.missed {
  border-color: #22c55e;
  background: #f0fdf4;
  border-style: dashed;
  cursor: default;
}

.quiz-option.submitted {
  cursor: default;
}

.quiz-option.submitted:hover {
  border-color: inherit;
  background: inherit;
}

.quiz-option-marker {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  border: 2px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 12px;
  font-weight: 700;
  color: var(--text-secondary);
  transition: all 0.2s;
  margin-top: 1px;
}

.quiz-option-marker.marker-checkbox {
  border-radius: 5px;
}

.quiz-option.selected .quiz-option-marker {
  border-color: var(--primary);
  background: var(--primary);
  color: #fff;
}

.quiz-option.correct .quiz-option-marker {
  border-color: #22c55e;
  background: #22c55e;
  color: #fff;
}

.quiz-option.incorrect .quiz-option-marker {
  border-color: var(--error);
  background: var(--error);
  color: #fff;
}

.quiz-option.missed .quiz-option-marker {
  border-color: #22c55e;
  background: transparent;
  color: #22c55e;
}

.quiz-option-text {
  flex: 1;
  font-size: 14px;
  line-height: 1.5;
  color: var(--text);
}

.quiz-option-text code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  font-size: 0.9em;
  background: #e8ecef;
  padding: 1px 5px;
  border-radius: 3px;
  color: var(--primary-dark);
}

/* Explanation */
.quiz-explanation {
  margin-top: 20px;
  padding: 16px 18px;
  background: var(--bg-secondary);
  border-radius: var(--radius);
  border-left: 3px solid var(--primary);
  animation: cardFadeIn 0.25s ease both;
}

.quiz-explanation-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 6px;
}

.quiz-explanation-text {
  font-size: 13px;
  line-height: 1.7;
  color: var(--text);
}

.quiz-explanation-text code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  font-size: 0.9em;
  background: #e0e4e8;
  padding: 1px 5px;
  border-radius: 3px;
  color: var(--primary-dark);
}

/* Buttons */
.quiz-actions {
  display: flex;
  gap: 10px;
  margin-top: 24px;
}

.quiz-btn {
  padding: 10px 24px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
}

.quiz-btn-primary {
  background: var(--primary);
  color: #fff;
}

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

.quiz-btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.quiz-btn-secondary {
  background: transparent;
  color: var(--text-secondary);
  border: 1.5px solid var(--border);
}

.quiz-btn-secondary:hover {
  border-color: var(--primary-light);
  color: var(--primary);
}

/* Result */
.quiz-result-icon {
  text-align: center;
  margin-bottom: 20px;
}

.quiz-result-score {
  text-align: center;
  margin-bottom: 8px;
}

.quiz-result-score .score-number {
  font-size: 48px;
  font-weight: 700;
  color: var(--primary);
}

.quiz-result-score .score-total {
  font-size: 20px;
  color: var(--text-secondary);
}

.quiz-result-label {
  text-align: center;
  font-size: 14px;
  color: var(--text-secondary);
  margin-bottom: 28px;
}

.quiz-result-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

/* Wrong Questions Section */
.quiz-wrong-section {
  margin-top: 28px;
  padding-top: 28px;
  border-top: 1px solid var(--border);
}

.quiz-wrong-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
  margin-bottom: 16px;
  text-align: center;
}

.quiz-wrong-topic {
  background: var(--bg-secondary);
  border-radius: var(--radius);
  padding: 16px 18px;
  margin-bottom: 14px;
  animation: cardFadeIn 0.3s ease both;
}

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

.quiz-wrong-topic-name {
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
}

.quiz-wrong-count {
  font-size: 12px;
  font-weight: 600;
  color: var(--primary);
  background: var(--primary-bg);
  padding: 2px 8px;
  border-radius: 12px;
}

.quiz-wrong-topic-questions {
  margin-bottom: 12px;
}

.quiz-wrong-item {
  font-size: 13px;
  color: var(--text-secondary);
  padding: 6px 0;
  padding-left: 14px;
  border-left: 2px solid var(--border);
  margin-bottom: 6px;
  line-height: 1.5;
}

.quiz-wrong-item code {
  font-family: 'SF Mono', 'Fira Code', 'Cascadia Code', 'Menlo', monospace;
  font-size: 0.9em;
  background: #e0e4e8;
  padding: 1px 5px;
  border-radius: 3px;
  color: var(--primary-dark);
}

.quiz-wrong-guidance {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text);
  padding: 10px 14px;
  background: rgba(13, 148, 136, 0.06);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--primary);
}

/* Quiz Loading & Error */
.quiz-loading {
  text-align: center;
  padding: 60px 20px;
  font-size: 15px;
  color: var(--text-secondary);
}

.quiz-error {
  text-align: center;
  padding: 60px 20px;
  font-size: 15px;
  color: var(--error);
}

/* Quiz Responsive */
@media (max-width: 768px) {
  .quiz-main {
    padding: 20px 14px 40px;
  }

  .quiz-card {
    padding: 24px 18px;
  }

  .quiz-nav {
    padding: 0 14px;
  }

  .quiz-progress-bar {
    width: 80px;
  }

  .quiz-question-text {
    font-size: 15px;
  }
}

/* ============ Practice Terminal Page ============ */
.practice-body {
  min-height: 100vh;
  background: linear-gradient(135deg, #f0fdfa 0%, #e0f2fe 50%, #f0fdfa 100%);
  display: flex;
  flex-direction: column;
}

/* Practice Navigation */
.practice-nav {
  background: rgba(255, 255, 255, 0.85);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(226, 232, 240, 0.7);
  padding: 0 24px;
  position: sticky;
  top: 0;
  z-index: 10;
}

.practice-nav-inner {
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.practice-back-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  transition: color 0.2s, background 0.2s;
}

.practice-back-btn:hover {
  color: var(--primary);
  background: rgba(13, 148, 136, 0.06);
}

.practice-title {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.practice-timer-area {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text-secondary);
  font-size: 14px;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', monospace;
}

/* Practice Main */
.practice-main {
  flex: 1;
  max-width: 1400px;
  margin: 0 auto;
  padding: 20px 24px 40px;
  width: 100%;
}

.practice-layout {
  display: grid;
  grid-template-columns: 280px 1fr;
  gap: 16px;
  height: calc(100vh - 80px);
}

/* Task Panel */
.task-panel {
  background: var(--bg);
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  box-shadow: var(--shadow);
  padding: 20px;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  max-height: 100%;
}

.task-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

.task-panel-header h3 {
  font-size: 16px;
  font-weight: 700;
  color: var(--text);
}

.task-progress {
  font-size: 13px;
  font-weight: 600;
  color: var(--primary);
}

.current-task-info {
  margin-bottom: 16px;
  padding: 14px;
  background: var(--primary-bg);
  border-radius: var(--radius-sm);
  border-left: 3px solid var(--primary);
}

.current-task-info h4 {
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--text);
}

.current-task-info p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
}

/* Task List */
.task-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 20px;
}

.task-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--border);
  transition: all 0.2s;
}

.task-item.completed {
  background: var(--primary-bg);
  border-color: rgba(13, 148, 136, 0.3);
}

.task-status {
  font-size: 14px;
  color: var(--text-secondary);
  width: 20px;
}

.task-item.completed .task-status {
  color: var(--primary);
}

.task-text {
  flex: 1;
  font-size: 13px;
  color: var(--text);
}

.task-score {
  font-size: 12px;
  color: var(--text-secondary);
}

/* Command Hints */
.command-ref-section {
  margin-bottom: 20px;
  padding: 14px;
  background: var(--bg-secondary);
  border-radius: var(--radius-sm);
}

.command-ref-section h4 {
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
}

.command-hints {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.hint-item {
  font-size: 12px;
  color: var(--text-secondary);
  line-height: 1.4;
}

.hint-item code {
  background: rgba(13, 148, 136, 0.1);
  color: var(--primary-dark);
  padding: 1px 4px;
  border-radius: 3px;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', monospace;
  font-size: 11px;
}

/* Achievement Section - hidden during active tasks */
.achievement-section {
  display: none;
}

.achievement-section h4 {
  font-size: 13px;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text);
}

.achievement-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.achievement-item {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  padding: 6px;
  border-radius: var(--radius-sm);
  transition: background 0.2s;
}

.achievement-item.unlocked {
  background: rgba(13, 148, 136, 0.1);
}

.achievement-icon {
  font-size: 14px;
}

.achievement-name {
  color: var(--text-secondary);
}

.achievement-item.unlocked .achievement-name {
  color: var(--primary);
  font-weight: 600;
}

/* Terminal Container */
.terminal-container {
  background: #1e1e1e;
  border-radius: var(--radius);
  border: 1px solid #333;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.terminal-header {
  background: #2d2d2d;
  padding: 10px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid #333;
}

.terminal-title {
  font-size: 12px;
  color: #999;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', monospace;
}

.terminal-controls {
  display: flex;
  gap: 6px;
}

.terminal-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}

.terminal-dot-red { background: #ff5f56; }
.terminal-dot-yellow { background: #ffbd2e; }
.terminal-dot-green { background: #28c840; }

.terminal-output {
  flex: 1;
  padding: 12px 14px;
  overflow-y: auto;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
  font-size: 14px;
  line-height: 1.4;
  background: #1e1e1e;
  color: #e0e0e0;
}

.terminal-line {
  white-space: pre-wrap;
  word-break: break-all;
}

.terminal-prompt {
  color: #4ec9b0;
  user-select: none;
}

.terminal-input-cursor {
  display: inline-block;
  width: 8px;
  height: 16px;
  background: #e0e0e0;
  animation: blink 1s step-end infinite;
  vertical-align: middle;
  margin-left: 2px;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.terminal-welcome {
  padding: 16px 0;
  text-align: center;
}

.terminal-welcome-art {
  font-size: 12px;
  line-height: 1.2;
  color: var(--primary);
  font-weight: bold;
  white-space: pre;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
  letter-spacing: 2px;
}

.terminal-welcome-text {
  font-size: 16px;
  font-weight: 700;
  color: var(--primary);
  margin-bottom: 8px;
}

.terminal-welcome-sub {
  font-size: 13px;
  color: #888;
  margin-bottom: 12px;
}

.terminal-welcome-hint {
  font-size: 12px;
  color: #666;
}

.terminal-welcome code {
  background: rgba(78, 201, 176, 0.15);
  color: #4ec9b0;
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 11px;
}

.terminal-output-text {
  color: #e0e0e0;
  white-space: pre-wrap;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', 'Consolas', monospace;
}

.terminal-error {
  color: #ff5f56;
}

.terminal-success {
  color: #4ec9b0;
  font-weight: 600;
}

.terminal-input-area {
  display: flex;
  align-items: center;
  padding: 8px 14px;
  background: #1e1e1e;
  border-top: 1px solid #333;
}

.terminal-input {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: transparent;
  font-family: 'SF Mono', 'Fira Code', 'Menlo', 'Ubuntu Mono', 'Consolas', monospace;
  font-size: 14px;
  caret-color: transparent;
  text-shadow: 0 0 0 transparent;
}

.terminal-input::selection {
  background: rgba(78, 201, 176, 0.3);
  color: #fff;
}

/* Result Modal */
.result-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  animation: modalFadeIn 0.25s ease both;
}

@keyframes modalFadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.result-modal-content {
  background: var(--bg);
  border-radius: 16px;
  padding: 32px 36px;
  max-width: 400px;
  width: 90%;
  text-align: center;
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
  animation: modalSlideUp 0.3s ease both;
}

@keyframes modalSlideUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.result-modal-icon {
  margin-bottom: 16px;
}

.result-stats {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 20px 0;
}

.result-stat {
  text-align: center;
}

.result-stat-label {
  display: block;
  font-size: 13px;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.result-stat-value {
  font-size: 24px;
  font-weight: 700;
  color: var(--primary);
}

.result-achievement {
  margin: 16px 0 20px;
}

.achievement-badge {
  display: inline-block;
  padding: 6px 16px;
  background: linear-gradient(135deg, #fbbf24 0%, #f59e0b 100%);
  color: #fff;
  border-radius: 20px;
  font-size: 13px;
  font-weight: 600;
}

.achievement-new {
  animation: achievementPop 0.5s ease both;
}

@keyframes achievementPop {
  0% {
    transform: scale(0.8);
    opacity: 0;
  }
  50% {
    transform: scale(1.1);
  }
  100% {
    transform: scale(1);
    opacity: 1;
  }
}

/* Terminal Scrollbar */
.terminal-output::-webkit-scrollbar {
  width: 8px;
}

.terminal-output::-webkit-scrollbar-track {
  background: #1e1e1e;
}

.terminal-output::-webkit-scrollbar-thumb {
  background: #444;
  border-radius: 4px;
}

.terminal-output::-webkit-scrollbar-thumb:hover {
  background: #555;
}

/* Practice Responsive */
@media (max-width: 900px) {
  .practice-layout {
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr;
  }
  
  .task-panel {
    max-height: none;
  }
  
  .task-list {
    max-height: 200px;
  }
}

@media (max-width: 768px) {
  .practice-main {
    padding: 12px 14px 20px;
  }
  
  .practice-nav {
    padding: 0 14px;
  }
  
  .practice-title {
    display: none;
  }
}
/* Module Icon - Practice */
.module-icon-practice {
  background: linear-gradient(135deg, #0d9488 0%, #14b8a6 100%);
}