/* ============================
   MindForge AI - 现代 UI 样式表
   ============================
   特性: 暗色/亮色主题、玻璃拟态、粒子背景、微交互动画
   ============================ */

/* ------------------------------------
   1. CSS 变量 & 主题
   ------------------------------------ */
:root {
  /* 共享变量 */
  --radius: 16px;
  --radius-sm: 10px;
  --radius-xs: 6px;
  --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', Consolas, monospace;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-fast: 0.15s ease;
  --transition-spring: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* 暗色主题 (默认) */
[data-theme="dark"] {
  --primary: #818cf8;
  --primary-hover: #6366f1;
  --primary-glow: rgba(129, 140, 248, 0.3);
  --primary-light: rgba(129, 140, 248, 0.12);
  --accent: #c084fc;
  --accent-glow: rgba(192, 132, 252, 0.3);

  --bg-base: #0b0f1a;
  --bg-elevated: rgba(17, 24, 45, 0.8);
  --bg-surface: rgba(30, 41, 70, 0.6);
  --bg-input: rgba(30, 41, 70, 0.5);

  --glass-bg: rgba(17, 24, 45, 0.65);
  --glass-border: rgba(255, 255, 255, 0.08);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);

  --text: #e2e8f0;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --border: rgba(255, 255, 255, 0.06);
  --border-hover: rgba(255, 255, 255, 0.12);

  --error: #f87171;
  --error-light: rgba(248, 113, 113, 0.1);
  --error-border: rgba(248, 113, 113, 0.25);
  --success: #34d399;
  --success-dark: #059669;
  --warning: #fb923c;
  --warning-dark: #ea580c;

  --gradient-primary: linear-gradient(135deg, #818cf8, #c084fc);
  --gradient-bg: radial-gradient(ellipse at top, #1a1f3a 0%, #0b0f1a 50%);
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.4);

  --scrollbar-thumb: rgba(255, 255, 255, 0.15);
  --scrollbar-track: transparent;
}

/* 亮色主题 */
[data-theme="light"] {
  --primary: #6366f1;
  --primary-hover: #4f46e5;
  --primary-glow: rgba(99, 102, 241, 0.25);
  --primary-light: rgba(99, 102, 241, 0.08);
  --accent: #a855f7;
  --accent-glow: rgba(168, 85, 247, 0.25);

  --bg-base: #f1f5f9;
  --bg-elevated: rgba(255, 255, 255, 0.85);
  --bg-surface: rgba(255, 255, 255, 0.65);
  --bg-input: rgba(255, 255, 255, 0.8);

  --glass-bg: rgba(255, 255, 255, 0.6);
  --glass-border: rgba(0, 0, 0, 0.06);
  --glass-shadow: 0 8px 32px rgba(0, 0, 0, 0.08);

  --text: #1e293b;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;

  --border: rgba(0, 0, 0, 0.06);
  --border-hover: rgba(0, 0, 0, 0.12);

  --error: #ef4444;
  --error-light: rgba(239, 68, 68, 0.08);
  --error-border: rgba(239, 68, 68, 0.2);
  --success: #22c55e;
  --success-dark: #16a34a;
  --warning: #f97316;
  --warning-dark: #ea580c;

  --gradient-primary: linear-gradient(135deg, #6366f1, #a855f7);
  --gradient-bg: radial-gradient(ellipse at top, #e0e7ff 0%, #f1f5f9 50%);
  --shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.1);

  --scrollbar-thumb: rgba(0, 0, 0, 0.15);
  --scrollbar-track: transparent;
}

/* ------------------------------------
   2. 全局重置 & 基础
   ------------------------------------ */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
  background: var(--bg-base);
  background-image: var(--gradient-bg);
  color: var(--text);
  min-height: 100vh;
  overflow-x: hidden;
  transition: background-color 0.5s ease, color 0.3s ease;
}

/* 自定义滚动条 */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: var(--scrollbar-track);
}
::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--primary-light);
}

/* 粒子画布 */
#particleCanvas {
  position: fixed;
  inset: 0;
  z-index: 0;
  pointer-events: none;
}

/* 通知容器 */
.toast-container {
  position: fixed;
  top: 20px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10000;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  padding: 12px 20px;
  border-radius: var(--radius-sm);
  font-size: 14px;
  font-weight: 500;
  backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  box-shadow: var(--shadow-lg);
  animation: toastIn 0.4s var(--transition) forwards;
  display: flex;
  align-items: center;
  gap: 8px;
}

.toast.toast-success {
  background: rgba(34, 197, 94, 0.15);
  color: var(--success);
  border-color: rgba(34, 197, 94, 0.2);
}
.toast.toast-error {
  background: var(--error-light);
  color: var(--error);
  border-color: var(--error-border);
}
.toast.toast-info {
  background: var(--primary-light);
  color: var(--primary);
  border-color: rgba(129, 140, 248, 0.2);
}
.toast.toast-out {
  animation: toastOut 0.3s ease forwards;
}

@keyframes toastIn {
  from { opacity: 0; transform: translateY(-12px) scale(0.95); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}
@keyframes toastOut {
  from { opacity: 1; transform: translateY(0) scale(1); }
  to { opacity: 0; transform: translateY(-12px) scale(0.95); }
}

/* ------------------------------------
   3. 玻璃拟态卡片
   ------------------------------------ */
.glass-card {
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--glass-shadow);
}

/* ------------------------------------
   4. 布局容器
   ------------------------------------ */
.app {
  position: relative;
  z-index: 1;
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 20px 24px;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/* ------------------------------------
   5. 顶部导航栏
   ------------------------------------ */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 0;
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.topbar-left, .topbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: default;
  user-select: none;
}

.logo-icon {
  font-size: 28px;
  line-height: 1;
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

.logo h1 {
  font-size: 22px;
  font-weight: 800;
  color: var(--text);
  letter-spacing: -0.5px;
}

.logo-ai {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-left: 2px;
}

.logo-version {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  margin-left: 6px;
  vertical-align: super;
  letter-spacing: 0;
  opacity: 0.6;
}

.icon-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.icon-btn:hover {
  color: var(--primary);
  border-color: var(--primary-glow);
  background: var(--primary-light);
  box-shadow: 0 0 20px var(--primary-glow);
  transform: translateY(-1px);
}

.icon-btn svg {
  flex-shrink: 0;
}

.theme-toggle {
  padding: 8px 12px;
}

.theme-icon {
  font-size: 16px;
  transition: transform 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.theme-toggle:hover .theme-icon {
  transform: rotate(30deg) scale(1.1);
}

.btn-label {
  font-size: 13px;
}

/* ------------------------------------
   6. Hero 区域
   ------------------------------------ */
.hero {
  text-align: center;
  padding: 48px 0 32px;
  animation: heroFadeIn 0.8s ease forwards;
}

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

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 16px;
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.5px;
  text-transform: uppercase;
  color: var(--primary);
  background: var(--primary-light);
  border: 1px solid rgba(129, 140, 248, 0.15);
  border-radius: 24px;
  margin-bottom: 20px;
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
  animation: badgePulse 2s ease-in-out infinite;
}

@keyframes badgePulse {
  0%, 100% { opacity: 1; box-shadow: 0 0 0 0 var(--primary-glow); }
  50% { opacity: 0.7; box-shadow: 0 0 0 6px transparent; }
}

.hero-title {
  font-size: 40px;
  font-weight: 800;
  line-height: 1.2;
  color: var(--text);
  margin-bottom: 16px;
  letter-spacing: -1px;
}

.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-desc {
  font-size: 16px;
  line-height: 1.7;
  color: var(--text-secondary);
  max-width: 520px;
  margin: 0 auto;
}

/* ------------------------------------
   7. 输入区域
   ------------------------------------ */
.input-section {
  margin-bottom: 20px;
  animation: slideUp 0.6s ease 0.2s both;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

.input-card {
  padding: 24px;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.input-card:hover {
  border-color: var(--border-hover);
}

/* Model Select */
.model-select-group {
  margin-bottom: 16px;
}

.select-wrapper {
  display: flex;
  align-items: center;
  gap: 10px;
}

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

.select-wrapper select {
  flex: 1;
  max-width: 340px;
  padding: 8px 14px;
  font-size: 13px;
  color: var(--text);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  cursor: pointer;
  transition: all var(--transition);
  appearance: auto;
}

.select-wrapper select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

/* Input Group */
.input-group {
  display: flex;
  gap: 10px;
}

.input-wrapper {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 10px;
  background: var(--bg-input);
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0 16px;
  transition: all var(--transition);
}

.input-wrapper:focus-within {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.input-icon {
  flex-shrink: 0;
  color: var(--text-muted);
  transition: color var(--transition);
}

.input-wrapper:focus-within .input-icon {
  color: var(--primary);
}

#topicInput {
  flex: 1;
  border: none;
  outline: none;
  font-size: 15px;
  padding: 14px 0;
  background: transparent;
  color: var(--text);
  font-family: inherit;
}

#topicInput::placeholder {
  color: var(--text-muted);
}

#generateBtn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 28px;
  background: var(--gradient-primary);
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 15px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
  min-width: 120px;
  position: relative;
  overflow: hidden;
}

#generateBtn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, rgba(255,255,255,0.2) 0%, transparent 60%);
  opacity: 0;
  transition: opacity var(--transition);
}

#generateBtn:hover:not(:disabled)::before {
  opacity: 1;
}

#generateBtn:hover:not(:disabled) {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--primary-glow), 0 0 40px var(--accent-glow);
}

#generateBtn:active:not(:disabled) {
  transform: translateY(0);
}

#generateBtn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.btn-text, .btn-loading {
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.spinner {
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

.error-msg {
  margin-top: 12px;
  padding: 12px 16px;
  background: var(--error-light);
  border: 1px solid var(--error-border);
  border-radius: var(--radius-sm);
  color: var(--error);
  font-size: 14px;
  animation: shake 0.4s ease;
}

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-6px); }
  75% { transform: translateX(6px); }
}

/* ===== Prompt Section ===== */
.prompt-section {
  margin-top: 16px;
}

/* Preset Bar */
.preset-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

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

.preset-chips {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.preset-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 16px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 20px;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.preset-btn:hover {
  color: var(--primary);
  border-color: var(--primary);
  background: var(--primary-light);
  transform: translateY(-1px);
}

.preset-btn.active {
  color: white;
  background: var(--gradient-primary);
  border-color: transparent;
  box-shadow: 0 4px 15px var(--primary-glow);
  transform: translateY(-1px);
}

.chip-emoji {
  font-size: 14px;
}

.prompt-toggle {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 4px;
  background: none;
  border: none;
  font-size: 13px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: color var(--transition);
  user-select: none;
}

.prompt-toggle:hover {
  color: var(--primary);
}

.prompt-toggle-arrow {
  transition: transform 0.3s ease;
}

.prompt-toggle-arrow.open {
  transform: rotate(90deg);
}

.prompt-toggle-hint {
  font-size: 11px;
  color: var(--text-muted);
  padding: 2px 8px;
  background: var(--bg-surface);
  border-radius: 10px;
}

.prompt-body {
  margin-top: 10px;
  animation: fadeSlideIn 0.3s ease;
}

@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(-8px); }
  to { opacity: 1; transform: translateY(0); }
}

.prompt-textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: 13px;
  line-height: 1.6;
  color: var(--text);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  resize: vertical;
  min-height: 120px;
  max-height: 400px;
  font-family: var(--font-mono);
  transition: all var(--transition);
}

.prompt-textarea:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.prompt-textarea::placeholder {
  color: var(--text-muted);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans SC', sans-serif;
}

.prompt-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 8px;
}

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

.prompt-action-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  font-size: 12px;
  color: var(--text-secondary);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}

.prompt-action-btn:hover {
  color: var(--primary);
  border-color: var(--primary);
  background: var(--primary-light);
}

.prompt-char-count {
  font-size: 12px;
  color: var(--text-muted);
}

/* ------------------------------------
   8. 工具栏 & 导出按钮
   ------------------------------------ */
.toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  margin-bottom: 12px;
  flex-wrap: wrap;
  gap: 8px;
  animation: fadeSlideIn 0.3s ease;
}

.toolbar-left, .toolbar-right {
  display: flex;
  gap: 6px;
}

.tab-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  color: var(--text-secondary);
}

.tab-btn:hover {
  color: var(--primary);
  border-color: var(--primary-glow);
  background: var(--primary-light);
}

.tab-btn.active {
  background: var(--primary-light);
  color: var(--primary);
  border-color: var(--primary);
  font-weight: 600;
  box-shadow: 0 0 15px var(--primary-glow);
}

.export-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 18px;
  border: none;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  color: white;
}

.export-btn:hover {
  transform: translateY(-2px);
}

.xmind-btn {
  background: linear-gradient(135deg, var(--warning), var(--warning-dark));
}

.xmind-btn:hover {
  box-shadow: 0 6px 20px rgba(249, 115, 22, 0.35);
}

.png-btn {
  background: linear-gradient(135deg, var(--success), var(--success-dark));
}

.png-btn:hover {
  box-shadow: 0 6px 20px rgba(34, 197, 94, 0.35);
}

.pdf-btn {
  background: linear-gradient(135deg, #e74c3c, #c0392b);
}

.pdf-btn:hover {
  box-shadow: 0 6px 20px rgba(231, 76, 60, 0.35);
}

/* ------------------------------------
   9. 内容区域
   ------------------------------------ */
.content-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 500px;
  animation: fadeSlideIn 0.4s ease;
}

.panel {
  flex: 1;
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--glass-shadow);
  overflow: hidden;
}

/* Markmap Preview */
.preview-panel {
  position: relative;
}

/* 思维导图画布始终使用浅色背景，确保可见性 */
.markmap-container {
  width: 100%;
  height: 100%;
  min-height: 65vh;
  background: #ffffff;
  border-radius: var(--radius);
  transition: background var(--transition);
}

[data-theme="dark"] .markmap-container {
  background: #f0f2f5;
}

#markmapSvg {
  width: 100%;
  height: 100%;
  min-height: 65vh;
}

/* 全屏按钮 */
.fullscreen-btn {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 11;
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.06);
  border: 1px solid rgba(0, 0, 0, 0.08);
  border-radius: 8px;
  cursor: pointer;
  color: #64748b;
  transition: all var(--transition);
  backdrop-filter: blur(8px);
}

.fullscreen-btn:hover {
  background: rgba(0, 0, 0, 0.12);
  color: #334155;
  transform: scale(1.05);
}

.fullscreen-btn svg {
  pointer-events: none;
}

/* 全屏模式下的样式 */
.preview-panel:fullscreen,
.preview-panel:-webkit-full-screen {
  background: #ffffff;
  border-radius: 0;
  padding: 0;
}

.preview-panel:fullscreen .markmap-container,
.preview-panel:-webkit-full-screen .markmap-container {
  min-height: 100vh;
  border-radius: 0;
}

.preview-panel:fullscreen #markmapSvg,
.preview-panel:-webkit-full-screen #markmapSvg {
  min-height: 100vh;
}

.preview-panel:fullscreen .fullscreen-btn,
.preview-panel:-webkit-full-screen .fullscreen-btn {
  top: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
}

.preview-panel:fullscreen .mm-toolbar,
.preview-panel:-webkit-full-screen .mm-toolbar {
  bottom: 20px;
  right: 20px;
}

/* 模拟全屏模式 (用于 iOS Safari 等不支持 Fullscreen API 的设备) */
.preview-panel.is-fake-fullscreen {
  position: fixed;
  inset: 0;
  z-index: 9999;
  width: 100vw;
  height: 100vh;
  height: 100dvh;
  background: #ffffff;
  border-radius: 0;
  padding: 0;
  margin: 0;
  overflow: hidden;
}

.preview-panel.is-fake-fullscreen .markmap-container {
  min-height: 100vh;
  min-height: 100dvh;
  border-radius: 0;
  height: 100vh;
  height: 100dvh;
}

.preview-panel.is-fake-fullscreen #markmapSvg {
  min-height: 100vh;
  min-height: 100dvh;
  height: 100vh;
  height: 100dvh;
}

.preview-panel.is-fake-fullscreen .fullscreen-btn {
  top: 16px;
  right: 16px;
  width: 44px;
  height: 44px;
  z-index: 10001;
  background: rgba(0, 0, 0, 0.12);
  border: 1px solid rgba(0, 0, 0, 0.1);
}

.preview-panel.is-fake-fullscreen .mm-toolbar {
  bottom: 20px;
  right: 20px;
  z-index: 10001;
}

/* 模拟全屏时隐藏其余页面内容，防止滚动穿透 */
body.fake-fullscreen-active {
  overflow: hidden;
  position: fixed;
  width: 100%;
}

/* 手机端模拟全屏的安全区域适配 */
@supports (padding: env(safe-area-inset-top)) {
  .preview-panel.is-fake-fullscreen .fullscreen-btn {
    top: calc(env(safe-area-inset-top, 0px) + 12px);
    right: calc(env(safe-area-inset-right, 0px) + 12px);
  }

  .preview-panel.is-fake-fullscreen .mm-toolbar {
    bottom: calc(env(safe-area-inset-bottom, 0px) + 16px);
    right: calc(env(safe-area-inset-right, 0px) + 16px);
  }
}

/* Markdown Panel */
.markdown-panel {
  padding: 24px;
  overflow: auto;
}

.markdown-content {
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.7;
  color: var(--text);
  white-space: pre-wrap;
  word-break: break-word;
}

/* ------------------------------------
   10. 历史记录面板
   ------------------------------------ */
.history-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 200;
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.history-overlay.open {
  display: block;
  opacity: 1;
}

.history-panel {
  position: fixed;
  top: 0;
  right: -420px;
  width: 400px;
  max-width: 92vw;
  height: 100vh;
  background: var(--bg-elevated);
  backdrop-filter: blur(30px);
  -webkit-backdrop-filter: blur(30px);
  border-left: 1px solid var(--glass-border);
  box-shadow: -8px 0 40px rgba(0, 0, 0, 0.2);
  z-index: 300;
  display: flex;
  flex-direction: column;
  transition: right 0.4s cubic-bezier(0.4, 0, 0.2, 1);
}

.history-panel.open {
  right: 0;
}

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

.history-panel-header h2 {
  font-size: 17px;
  font-weight: 700;
  color: var(--text);
  display: flex;
  align-items: center;
  gap: 10px;
}

.history-close-btn {
  width: 36px;
  height: 36px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: none;
  background: var(--bg-surface);
  color: var(--text-secondary);
  cursor: pointer;
  border-radius: 50%;
  transition: all var(--transition);
}

.history-close-btn:hover {
  background: var(--error-light);
  color: var(--error);
  transform: rotate(90deg);
}

.history-panel-actions {
  padding: 12px 20px 0;
  display: flex;
  justify-content: flex-end;
}

.history-clear-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  font-size: 12px;
  color: var(--error);
  background: var(--error-light);
  border: 1px solid var(--error-border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}

.history-clear-btn:hover {
  background: var(--error-light);
  border-color: var(--error);
  box-shadow: 0 0 15px rgba(248, 113, 113, 0.2);
}

.history-panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 12px 16px 20px;
}

.history-empty {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
  color: var(--text-secondary);
  text-align: center;
}

.history-empty-icon {
  font-size: 48px;
  margin-bottom: 12px;
  opacity: 0.7;
}

.history-empty p {
  font-size: 14px;
  margin-top: 4px;
}

.history-empty-hint {
  font-size: 12px !important;
  opacity: 0.5;
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.history-item {
  display: flex;
  align-items: stretch;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: all var(--transition);
  overflow: hidden;
}

.history-item:hover {
  border-color: var(--primary);
  background: var(--primary-light);
  box-shadow: 0 4px 15px var(--primary-glow);
  transform: translateX(-4px);
}

.history-item-main {
  flex: 1;
  padding: 14px 16px;
  cursor: pointer;
  min-width: 0;
}

.history-item-topic {
  font-size: 14px;
  font-weight: 600;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.history-item-summary {
  font-size: 12px;
  color: var(--text-secondary);
  margin-top: 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.history-item-time {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 6px;
}

.history-item-delete {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  min-width: 40px;
  border: none;
  background: none;
  color: var(--text-muted);
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition);
  opacity: 0;
}

.history-item:hover .history-item-delete {
  opacity: 1;
}

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

/* ------------------------------------
   11. 对话式修改区域
   ------------------------------------ */
.chat-section {
  display: flex;
  flex-direction: column;
  margin-top: 16px;
  background: var(--glass-bg);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--glass-shadow);
  overflow: hidden;
  max-height: 480px;
  animation: fadeSlideIn 0.4s ease;
}

.chat-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.chat-header-left {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chat-header-icon {
  font-size: 18px;
}

.chat-header h3 {
  font-size: 14px;
  font-weight: 700;
  color: var(--text);
}

.chat-header-hint {
  font-size: 12px;
  color: var(--text-muted);
  padding: 2px 8px;
  background: var(--bg-surface);
  border-radius: 10px;
}

.chat-header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.chat-model-select {
  padding: 4px 8px;
  font-size: 11px;
  color: var(--text-secondary);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  cursor: pointer;
  max-width: 150px;
  transition: all var(--transition);
  appearance: auto;
}

.chat-model-select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 2px var(--primary-glow);
}

.chat-clear-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  font-size: 12px;
  color: var(--text-secondary);
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all var(--transition);
}

.chat-clear-btn:hover {
  color: var(--error);
  border-color: var(--error);
  background: var(--error-light);
}

.chat-clear-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
  pointer-events: none;
}

/* Quick bar */
.chat-quick-bar {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 20px;
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  flex-shrink: 0;
  -webkit-overflow-scrolling: touch;
}

.chat-quick-bar::-webkit-scrollbar {
  height: 0;
}

.chat-quick-btn {
  padding: 5px 12px;
  font-size: 12px;
  color: var(--text-secondary);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 16px;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
  flex-shrink: 0;
}

.chat-quick-btn:hover {
  color: var(--primary);
  border-color: var(--primary);
  background: var(--primary-light);
  transform: translateY(-1px);
}

/* Chat body */
.chat-body {
  flex: 1;
  overflow-y: auto;
  padding: 14px 20px;
  min-height: 120px;
  max-height: 260px;
}

.chat-messages {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.chat-msg {
  display: flex;
  gap: 10px;
  max-width: 85%;
  animation: chatFadeIn 0.3s ease;
}

@keyframes chatFadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.chat-msg-user {
  align-self: flex-end;
  flex-direction: row-reverse;
}

.chat-msg-assistant {
  align-self: flex-start;
}

.chat-msg-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  flex-shrink: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border);
}

.chat-msg-bubble {
  padding: 10px 14px;
  border-radius: 16px;
  font-size: 13px;
  line-height: 1.6;
  word-break: break-word;
  white-space: pre-wrap;
}

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

.chat-msg-assistant .chat-msg-bubble {
  background: var(--bg-surface);
  color: var(--text);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
}

.chat-msg-thinking {
  animation: pulse 1.5s ease-in-out infinite;
  color: var(--text-muted) !important;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* Chat input */
.chat-input-bar {
  display: flex;
  align-items: flex-end;
  gap: 10px;
  padding: 14px 20px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}

.chat-input {
  flex: 1;
  padding: 10px 14px;
  font-size: 13px;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  resize: none;
  min-height: 40px;
  max-height: 120px;
  transition: all var(--transition);
  font-family: inherit;
}

.chat-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}

.chat-input::placeholder {
  color: var(--text-muted);
}

.chat-send-btn {
  width: 42px;
  height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  background: var(--gradient-primary);
  border: none;
  border-radius: 50%;
  cursor: pointer;
  transition: all var(--transition);
  flex-shrink: 0;
}

.chat-send-btn:hover:not(:disabled) {
  transform: scale(1.08);
  box-shadow: 0 4px 20px var(--primary-glow);
}

.chat-send-btn:active:not(:disabled) {
  transform: scale(0.95);
}

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

/* ------------------------------------
   12. 底部
   ------------------------------------ */
.footer {
  text-align: center;
  padding: 32px 0 16px;
  color: var(--text-muted);
  font-size: 13px;
}

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

.footer a:hover {
  text-decoration: underline;
}

/* ------------------------------------
   13. 响应式适配
   ------------------------------------ */
@media (max-width: 640px) {
  .app {
    padding: 0 12px 16px;
  }

  .topbar {
    padding: 12px 0;
  }

  .logo h1 {
    font-size: 18px;
  }

  .logo-icon {
    font-size: 22px;
  }

  .btn-label {
    display: none;
  }

  .hero {
    padding: 32px 0 24px;
  }

  .hero-title {
    font-size: 28px;
  }

  .hero-desc {
    font-size: 14px;
  }

  .input-card {
    padding: 16px;
  }

  .input-group {
    flex-direction: column;
  }

  #generateBtn {
    width: 100%;
    padding: 14px;
  }

  .select-wrapper select {
    max-width: 100%;
  }

  .preset-bar {
    flex-wrap: wrap;
    gap: 8px;
  }

  .preset-btn {
    padding: 6px 12px;
    font-size: 12px;
  }

  .toolbar {
    flex-direction: column;
    align-items: stretch;
  }

  .toolbar-left, .toolbar-right {
    justify-content: center;
    flex-wrap: wrap;
  }

  .export-btn {
    padding: 8px 12px;
    font-size: 12px;
  }

  .markmap-container, #markmapSvg {
    min-height: 50vh;
  }

  .chat-section {
    max-height: 400px;
  }

  .chat-header-hint {
    display: none;
  }

  .chat-header {
    flex-wrap: wrap;
    gap: 8px;
    padding: 10px 12px;
  }

  .chat-header-actions {
    flex-wrap: wrap;
    gap: 6px;
  }

  .chat-model-select {
    max-width: 110px;
    font-size: 10px;
  }

  .chat-clear-btn {
    padding: 4px 8px;
    font-size: 10px;
    gap: 3px;
  }

  .chat-clear-btn svg {
    width: 12px;
    height: 12px;
  }

  .chat-quick-bar {
    padding: 8px 12px;
  }

  .chat-body {
    padding: 10px 12px;
    min-height: 100px;
    max-height: 200px;
  }

  .chat-msg {
    max-width: 92%;
  }

  .chat-input-bar {
    padding: 10px 12px;
  }

  .history-panel {
    width: 100vw;
    max-width: 100vw;
    right: -100vw;
  }

  .history-item-delete {
    opacity: 1;
  }

  /* 手机端全屏按钮更大，方便触摸 */
  .fullscreen-btn {
    width: 42px;
    height: 42px;
    top: 8px;
    right: 8px;
  }

  /* 手机端模拟全屏微调 */
  .preview-panel.is-fake-fullscreen .fullscreen-btn {
    top: 12px;
    right: 12px;
    width: 48px;
    height: 48px;
  }
}

/* ------------------------------------
   14. Markmap Toolbar 覆盖
   ------------------------------------ */
.mm-toolbar {
  position: absolute;
  bottom: 12px;
  right: 12px;
  z-index: 10;
}

/* ------------------------------------
   15. 主题切换动画
   ------------------------------------ */
.theme-transitioning,
.theme-transitioning *,
.theme-transitioning *::before,
.theme-transitioning *::after {
  transition-duration: 0.5s !important;
}