/* =============================================
   CH Helper - Mobile App CSS (v7)
   所有规则前缀 .mobile-mode，完全隔离桌面端
   ============================================= */


/* ── CSS Variables ── */
:root {
  --mob-tab-h: 64px;
  --mob-top-h: 52px;
  --mob-safe-bottom: env(safe-area-inset-bottom, 0px);
  --mob-bg: #f8fafc;
  --mob-card-bg: #ffffff;
  --mob-text: #0f172a;
  --mob-text-secondary: #64748b;
  --mob-text-muted: #94a3b8;
  --mob-accent: #2563eb;
  --mob-accent-light: #3b82f6;
  --mob-accent-bg: rgba(37,99,235,0.08);
  --mob-border: #e2e8f0;
  --mob-shadow: 0 1px 3px rgba(0,0,0,0.06);
  --mob-shadow-lg: 0 10px 40px rgba(0,0,0,0.1);
}

[data-theme="dark"] body {
  --mob-bg: #0f172a;
  --mob-card-bg: #1e293b;
  --mob-text: #f1f5f9;
  --mob-text-secondary: #94a3b8;
  --mob-text-muted: #64748b;
  --mob-accent: #3b82f6;
  --mob-accent-light: #60a5fa;
  --mob-accent-bg: rgba(59,130,246,0.12);
  --mob-border: #334155;
  --mob-shadow: 0 1px 3px rgba(0,0,0,0.2);
  --mob-shadow-lg: 0 10px 40px rgba(0,0,0,0.3);
}

/* ===== 核心布局 ===== */

.mobile-mode .mob-app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  padding-top: 52px;    /* 给顶部导航栏留空间 */
  padding-bottom: 60px;  /* 给底部 Tab 栏留空间 */
  overflow-x: hidden;
}

.mobile-mode .site-header,
.mobile-mode .site-footer,
.mobile-mode .proof-section,
.mobile-mode .cta-section {
  display: none !important;
}

/* 通用：隐藏所有子页面的桌面 header/nav/footer */
.mobile-mode body > header:first-of-type,
.mobile-mode header[class*="sticky"],
.mobile-mode nav:not(.mob-top-bar):not(.mob-tab-bar),
.mobile-mode footer:not(.mob-tab-bar) {
  display: none !important;
}

.mobile-mode .site-main {
  max-width: 100% !important;
  padding: 0 !important;
  margin: 0 !important;
}

.mobile-mode .hero-section {
  padding-top: 12px !important;
  padding-left: 12px !important;
  padding-right: 12px !important;
}

.mobile-mode .quick-section,
.mobile-mode .demo-section {
  padding-left: 12px !important;
  padding-right: 12px !important;
}

/* ===== 顶部导航栏 ===== */

.mobile-mode .mob-top-bar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px;
  background: var(--header-bg, #fff);
  border-bottom: 1px solid rgba(128,128,128,0.12);
  z-index: 1001;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.mobile-mode .mob-top-logo {
  font-size: 17px;
  font-weight: 700;
  color: var(--primary, #007AFF);
}

.mobile-mode .mob-top-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}

.mobile-mode .mob-top-btn {
  background: none;
  border: none;
  font-size: 20px;
  padding: 6px;
  cursor: pointer;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  min-width: 36px;
  min-height: 36px;
  transition: background .2s;
}

.mobile-mode .mob-top-btn:active {
  background: rgba(128,128,128,0.12);
}

/* ===== 底部 Tab 栏 ===== */

.mobile-mode .mob-tab-bar {
  position: fixed;
  bottom: 0; left: 0; right: 0;
  height: 60px;
  display: flex;
  align-items: stretch;
  background: var(--header-bg, #fff);
  border-top: 1px solid rgba(128,128,128,0.12);
  z-index: 1000;
  padding-bottom: env(safe-area-inset-bottom, 0);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.mobile-mode .mob-tab {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  background: none;
  border: none;
  font-size: 10px;
  color: var(--text-muted, #888);
  cursor: pointer;
  transition: color .2s;
  -webkit-tap-highlight-color: transparent;
}

.mobile-mode .mob-tab .mob-tab-icon {
  font-size: 22px;
  line-height: 1;
}

.mobile-mode .mob-tab.active {
  color: var(--primary, #007AFF);
}

/* ===== Tab 内容面板 ===== */

.mobile-mode .mob-tab-content {
  display: none;
  flex: 1;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  padding: 12px;
}

.mobile-mode .mob-tab-content.active {
  display: block;
}

/* ===== 搜索 Tab ===== */

.mobile-mode .mob-search-bar {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}

.mobile-mode .mob-search-input {
  flex: 1;
  padding: 10px 14px;
  border: 1px solid rgba(128,128,128,0.2);
  border-radius: 10px;
  font-size: 15px;
  background: var(--card-bg, #fff);
  color: var(--text, #222);
  outline: none;
}

.mobile-mode .mob-search-input:focus {
  border-color: var(--primary, #007AFF);
}

.mobile-mode .mob-search-btn {
  padding: 10px 16px;
  background: var(--primary, #007AFF);
  color: #fff;
  border: none;
  border-radius: 10px;
  font-size: 15px;
  cursor: pointer;
  transition: opacity .2s;
}

.mobile-mode .mob-search-btn:active {
  opacity: 0.8;
}

.mobile-mode .mob-search-results {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* ===== 词库 Tab ===== */
/* ===== 词库 Tab - 实际使用的类名（与JS buildWordbankContent 匹配） ===== */

/* 分类按钮容器 */
.mobile-mode .mob-wordbank-cats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 10px;
  margin-bottom: 16px;
}

/* 单个分类按钮 (.mob-wb-cat) */
.mobile-mode .mob-wb-cat {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 14px 8px;
  background: var(--card-bg, #fff);
  border-radius: 14px;
  border: 1px solid rgba(128,128,128,0.1);
  cursor: pointer;
  transition: transform .15s, box-shadow .15s, border-color .15s;
  -webkit-tap-highlight-color: transparent;
}
.mobile-mode .mob-wb-cat:active {
  transform: scale(0.95);
}
.mobile-mode .mob-wb-cat.active {
  border-color: #6366f1;
  background: rgba(99,102,241,0.06);
}

.mobile-mode .mob-wb-cat-icon {
  font-size: 30px;
  margin-bottom: 6px;
  line-height: 1;
}

.mobile-mode .mob-wb-cat-label {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text, #222);
}

/* 词汇列表容器 */
.mobile-mode .mob-wordbank-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

/* 单个词汇卡片 */
.mobile-mode .mob-wb-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 13px 14px;
  background: var(--card-bg, #fff);
  border-radius: 12px;
  border: 1px solid rgba(128,128,128,0.08);
  cursor: pointer;
  transition: background .15s;
  -webkit-tap-highlight-color: transparent;
}
.mobile-mode .mob-wb-card:active {
  background: rgba(0,0,0,0.03);
}

.mobile-mode .mob-wb-card-main {
  display: flex;
  flex-direction: column;
  gap: 2px;
  min-width: 0;
  flex: 1;
}

.mobile-mode .mob-wb-card-cn {
  font-size: 16px;
  font-weight: 600;
  color: var(--text, #1a1a2e);
}

.mobile-mode .mob-wb-card-en {
  font-size: 12.5px;
  color: var(--text-muted, #888);
}

.mobile-mode .mob-wb-card-ph {
  font-size: 13px;
  color: #6366f1;
  font-weight: 500;
  margin-right: 10px;
  white-space: nowrap;
}

.mobile-mode .mob-wb-card-fav {
  width: 34px; height: 34px;
  border-radius: 50%;
  border: none;
  background: transparent;
  font-size: 18px;
  color: #ccc;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  -webkit-tap-highlight-color: transparent;
}
.mobile-mode .mob-wb-card-fav.active {
  color: #ef4444;
}

/* 词库空状态 */
.mobile-mode .mob-wordbank-empty {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-muted, #aaa);
}
.mobile-mode .mob-placeholder-icon {
  font-size: 40px;
  margin-bottom: 10px;
}



.mobile-mode .mob-wordbank-header {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text, #222);
}

.mobile-mode .mob-wordbank-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  margin-bottom: 16px;
}

.mobile-mode .mob-wordbank-cat {
  padding: 14px;
  background: var(--card-bg, #fff);
  border-radius: 12px;
  border: 1px solid rgba(128,128,128,0.1);
  text-align: center;
  cursor: pointer;
  transition: transform .2s, box-shadow .2s;
}

.mobile-mode .mob-wordbank-cat:active {
  transform: scale(0.97);
}

.mobile-mode .mob-wordbank-cat-icon {
  font-size: 28px;
  margin-bottom: 6px;
}

.mobile-mode .mob-wordbank-cat-name {
  font-size: 13px;
  font-weight: 600;
  color: var(--text, #222);
}

.mobile-mode .mob-wordbank-cat-count {
  font-size: 11px;
  color: var(--text-muted, #888);
  margin-top: 2px;
}

.mobile-mode .mob-word-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.mobile-mode .mob-word-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 14px;
  background: var(--card-bg, #fff);
  border-radius: 10px;
  border: 1px solid rgba(128,128,128,0.08);
}

.mobile-mode .mob-word-item-left {
  display: flex;
  flex-direction: column;
}

.mobile-mode .mob-word-item-ch {
  font-size: 16px;
  font-weight: 600;
  color: var(--text, #222);
}

.mobile-mode .mob-word-item-pinyin {
  font-size: 12px;
  color: var(--text-muted, #888);
}

.mobile-mode .mob-word-item-audio {
  background: none;
  border: none;
  font-size: 20px;
  cursor: pointer;
  padding: 4px;
}

/* ===== 学习 Tab ===== */

.mobile-mode .mob-learn-header {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text, #222);
}

.mobile-mode .mob-flashcard {
  perspective: 1000px;
  width: 100%;
  height: 220px;
  margin-bottom: 16px;
  cursor: pointer;
}

.mobile-mode .mob-flashcard-inner {
  position: relative;
  width: 100%;
  height: 100%;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}

.mobile-mode .mob-flashcard.flipped .mob-flashcard-inner {
  transform: rotateY(180deg);
}

.mobile-mode .mob-flashcard-front,
.mobile-mode .mob-flashcard-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: var(--card-bg, #fff);
  border: 1px solid rgba(128,128,128,0.1);
  box-shadow: 0 2px 12px rgba(0,0,0,0.06);
}

.mobile-mode .mob-flashcard-back {
  transform: rotateY(180deg);
}

.mobile-mode .mob-flashcard-ch {
  font-size: 36px;
  font-weight: 700;
  color: var(--primary, #007AFF);
}

.mobile-mode .mob-flashcard-pinyin {
  font-size: 16px;
  color: var(--text-muted, #888);
  margin-top: 8px;
}

.mobile-mode .mob-flashcard-meaning {
  font-size: 18px;
  color: var(--text, #222);
}

.mobile-mode .mob-flashcard-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
}

.mobile-mode .mob-flashcard-btn {
  padding: 10px 24px;
  border-radius: 20px;
  border: none;
  font-size: 15px;
  cursor: pointer;
  transition: transform .2s, opacity .2s;
}

.mobile-mode .mob-flashcard-btn:active {
  transform: scale(0.96);
}

.mobile-mode .mob-flashcard-btn-know {
  background: var(--primary, #007AFF);
  color: #fff;
}

.mobile-mode .mob-flashcard-btn-dontknow {
  background: rgba(255,59,48,0.1);
  color: #FF3B30;
}

/* ===== 个人 Tab（Profile）===== */

.mobile-mode .mob-profile-header {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 24px 0 16px;
}

.mobile-mode .mob-profile-avatar {
  width: 72px;
  height: 72px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--primary, #007AFF), #5856D6);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 32px;
  color: #fff;
  margin-bottom: 10px;
  box-shadow: 0 4px 12px rgba(0,122,255,0.3);
}

.mobile-mode .mob-profile-name {
  font-size: 18px;
  font-weight: 700;
  color: var(--text, #222);
}

.mobile-mode .mob-profile-email {
  font-size: 13px;
  color: var(--text-muted, #888);
  margin-top: 2px;
}

.mobile-mode .mob-profile-stats {
  display: flex;
  justify-content: center;
  gap: 32px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(128,128,128,0.1);
  margin-bottom: 8px;
}

.mobile-mode .mob-profile-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.mobile-mode .mob-profile-stat-num {
  font-size: 20px;
  font-weight: 700;
  color: var(--primary, #007AFF);
}

.mobile-mode .mob-profile-stat-label {
  font-size: 11px;
  color: var(--text-muted, #888);
  margin-top: 2px;
}

.mobile-mode .mob-profile-menu {
  display: flex;
  flex-direction: column;
  gap: 0;
}

/* ===== 菜单项（通用）===== */

.mobile-mode .mob-menu-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  font-size: 15px;
  color: var(--text, #222);
  cursor: pointer;
  border-bottom: 1px solid rgba(128,128,128,0.06);
  transition: background .2s;
}

.mobile-mode .mob-menu-item:active {
  background: rgba(128,128,128,0.06);
}

.mobile-mode .mob-menu-icon {
  font-size: 20px;
  width: 28px;
  text-align: center;
  flex-shrink: 0;
}

.mobile-mode .mob-menu-label {
  flex: 1;
}

.mobile-mode .mob-menu-arrow {
  font-size: 14px;
  color: var(--text-muted, #bbb);
}

/* ===== 认证按钮 ===== */

.mobile-mode .mob-auth-btn {
  display: block;
  width: calc(100% - 32px);
  margin: 16px auto;
  padding: 12px;
  border-radius: 12px;
  border: none;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: transform .2s, opacity .2s;
}

.mobile-mode .mob-auth-btn:active {
  transform: scale(0.98);
  opacity: 0.9;
}

.mobile-mode .mob-auth-btn-primary {
  background: var(--primary, #007AFF);
  color: #fff;
}

.mobile-mode .mob-auth-btn-outline {
  background: transparent;
  border: 1px solid rgba(128,128,128,0.2);
  color: var(--text, #222);
}

.mobile-mode .mob-auth-btn-danger {
  background: rgba(255,59,48,0.08);
  color: #FF3B30;
}

/* ===== 语言选择器浮层 ===== */

.mobile-mode .mob-lang-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.4);
  z-index: 9999;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.mobile-mode .mob-lang-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.mobile-mode .mob-lang-sheet {
  width: 100%;
  max-width: 420px;
  max-height: 60vh;
  background: var(--card-bg, #fff);
  border-radius: 20px 20px 0 0;
  padding: 16px 0 24px;
  transform: translateY(100%);
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
}

.mobile-mode .mob-lang-overlay.active .mob-lang-sheet {
  transform: translateY(0);
}

.mobile-mode .mob-lang-handle {
  width: 36px;
  height: 4px;
  background: rgba(128,128,128,0.2);
  border-radius: 2px;
  margin: 0 auto 12px;
}

.mobile-mode .mob-lang-title {
  font-size: 15px;
  font-weight: 600;
  text-align: center;
  margin-bottom: 12px;
  color: var(--text, #222);
}

.mobile-mode .mob-lang-opt {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 20px;
  background: none;
  border: none;
  width: 100%;
  text-align: left;
  font-size: 15px;
  color: var(--text, #222);
  cursor: pointer;
  transition: background .2s;
}

.mobile-mode .mob-lang-opt:active {
  background: rgba(128,128,128,0.06);
}

.mobile-mode .mob-lang-opt.active {
  color: var(--primary, #007AFF);
  font-weight: 600;
}

.mobile-mode .mob-lang-flag {
  font-size: 22px;
}

/* ===== Settings & About 浮层（覆盖层）===== */

.mobile-mode .mob-overlay {
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0,0,0,0.4);
  z-index: 9999;
  display: flex;
  align-items: flex-end;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s;
}

.mobile-mode .mob-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.mobile-mode .mob-overlay-sheet {
  width: 100%;
  max-width: 420px;
  max-height: 85vh;
  background: var(--card-bg, #fff);
  border-radius: 20px 20px 0 0;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  transform: translateY(100%);
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
}

.mobile-mode .mob-overlay.active .mob-overlay-sheet {
  transform: translateY(0);
}

.mobile-mode .mob-overlay-handle {
  width: 36px;
  height: 4px;
  background: rgba(128,128,128,0.2);
  border-radius: 2px;
  margin: 8px auto 4px;
  flex-shrink: 0;
}

.mobile-mode .mob-overlay-title {
  font-size: 17px;
  font-weight: 700;
  text-align: center;
  padding: 8px 0 12px;
  color: var(--text, #222);
}

.mobile-mode .mob-overlay-close {
  position: absolute;
  top: 8px;
  right: 12px;
  background: rgba(128,128,128,0.08);
  border: none;
  font-size: 18px;
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: background .2s;
}

.mobile-mode .mob-overlay-close:active {
  background: rgba(128,128,128,0.15);
}

/* ===== Settings 内容 ===== */

.mobile-mode .mob-settings-content {
  padding: 16px 20px 24px;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  flex: 1;
}

.mobile-mode .mob-settings-section {
  margin-bottom: 20px;
}

.mobile-mode .mob-settings-heading {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-muted, #888);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin: 0 0 10px 0;
}

.mobile-mode .mob-settings-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 0;
  border-bottom: 1px solid rgba(128,128,128,0.15);
}

.mobile-mode .mob-settings-row-btn {
  border-bottom: none;
  justify-content: center;
}

.mobile-mode .mob-settings-label {
  font-size: 15px;
  color: var(--text, #222);
}

/* Toggle Switch */
.mobile-mode .mob-toggle {
  position: relative;
  display: inline-block;
  width: 48px;
  height: 26px;
  flex-shrink: 0;
}

.mobile-mode .mob-toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.mobile-mode .mob-toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0; left: 0; right: 0; bottom: 0;
  background-color: #ccc;
  border-radius: 26px;
  transition: .3s;
}

.mobile-mode .mob-toggle-slider::before {
  content: "";
  position: absolute;
  height: 20px;
  width: 20px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  border-radius: 50%;
  transition: .3s;
  box-shadow: 0 1px 3px rgba(0,0,0,0.2);
}

.mobile-mode .mob-toggle input:checked + .mob-toggle-slider {
  background-color: #007AFF;
}

.mobile-mode .mob-toggle input:checked + .mob-toggle-slider::before {
  transform: translateX(22px);
}

/* Settings Buttons */
.mobile-mode .mob-settings-btn {
  display: block;
  width: 100%;
  padding: 10px;
  border: 1px solid rgba(128,128,128,0.3);
  border-radius: 10px;
  background: transparent;
  color: var(--text, #222);
  font-size: 14px;
  cursor: pointer;
  transition: background .2s;
}

.mobile-mode .mob-settings-btn:active {
  background: rgba(128,128,128,0.1);
}

.mobile-mode .mob-settings-btn-danger {
  color: #FF3B30;
  border-color: rgba(255,59,48,0.3);
}

.mobile-mode .mob-settings-btn-danger:active {
  background: rgba(255,59,48,0.1);
}

/* ===== About 内容 ===== */

.mobile-mode .mob-about-content {
  padding: 24px 20px;
  text-align: center;
  overflow-y: auto;
  -webkit-overflow-scrolling: touch;
  flex: 1;
}

.mobile-mode .mob-about-logo {
  font-size: 48px;
  margin-bottom: 8px;
}

.mobile-mode .mob-about-app-name {
  font-size: 20px;
  font-weight: 700;
  margin: 0 0 4px 0;
  color: var(--text, #222);
}

.mobile-mode .mob-about-version {
  font-size: 13px;
  color: var(--text-muted, #888);
  margin: 0 0 16px 0;
}

.mobile-mode .mob-about-desc {
  font-size: 14px;
  color: var(--text-muted, #666);
  line-height: 1.5;
  margin: 0 0 24px 0;
  padding: 0 12px;
}

.mobile-mode .mob-about-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 24px;
}

.mobile-mode .mob-about-link {
  display: block;
  padding: 12px;
  background: rgba(128,128,128,0.06);
  border-radius: 10px;
  color: var(--text, #222);
  text-decoration: none;
  font-size: 15px;
  transition: background .2s;
}

.mobile-mode .mob-about-link:active {
  background: rgba(128,128,128,0.12);
}

.mobile-mode .mob-about-copy {
  font-size: 12px;
  color: var(--text-muted, #aaa);
  margin: 0;
}

/* ===== Done 按钮 ===== */

.mobile-mode .mob-done-btn {
  display: block;
  width: calc(100% - 40px);
  margin: 16px auto 0;
  padding: 12px;
  background: var(--primary, #007AFF);
  color: #fff;
  border: none;
  border-radius: 12px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: opacity .2s;
}

.mobile-mode .mob-done-btn:active {
  opacity: 0.8;
}

/* ===== 暗色主题适配 ===== */

[data-theme="dark"] .mobile-mode .mob-top-bar,
[data-theme="dark"] .mobile-mode .mob-tab-bar {
  background: rgba(28,28,30,0.95);
  border-color: rgba(255,255,255,0.08);
}

[data-theme="dark"] .mobile-mode .mob-overlay-sheet,
[data-theme="dark"] .mobile-mode .mob-lang-sheet {
  background: #1c1c1e;
}

[data-theme="dark"] .mobile-mode .mob-toggle-slider {
  background-color: #444;
}

[data-theme="dark"] .mobile-mode .mob-wordbank-cat,
[data-theme="dark"] .mobile-mode .mob-word-item,
[data-theme="dark"] .mobile-mode .mob-flashcard-front,
[data-theme="dark"] .mobile-mode .mob-flashcard-back {
  background: #2c2c2e;
  border-color: rgba(255,255,255,0.08);
}

/* ===== 安全区域（刘海屏）===== */

@supports (padding-top: env(safe-area-inset-top)) {
  .mobile-mode .mob-top-bar {
    padding-top: env(safe-area-inset-top);
    height: calc(52px + env(safe-area-inset-top));
  }
}

.mobile-mode #feedbackBtn { bottom: 84px !important; }

/* ===== 子页面移动端适配 (terms, privacy, login 等) ===== */
.mobile-mode.mob-sub-page .mob-top-bar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  background: var(--card-bg, #fff);
  border-bottom: 1px solid var(--border-color, rgba(0,0,0,0.08));
  z-index: 1000;
}

.mobile-mode.mob-sub-page .mob-back-btn {
  width: 38px; height: 38px;
  border-radius: 50%;
  border: none;
  background: transparent;
  color: var(--text-primary, #1a1a2e);
  font-size: 1.3rem;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: background .2s;
}
.mobile-mode.mob-sub-page .mob-back-btn:active {
  background: rgba(0,0,0,0.06);
}

.mobile-mode.mob-sub-page .mob-top-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary, #1a1a2e);
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
  max-width: calc(100% - 100px);
}

/* ═══ 子页面移动端适配（纯CSS，不依赖JS） ═══ */
body.mobile-mode > header:first-of-type,
body.mobile-mode header.sticky,
body.mobile-mode nav:not(.mob-top-bar):not(.mob-tab-bar),
body.mobile-mode footer:not(.mob-tab-bar) {
  display: none !important;
}

body.mobile-mode .mob-top-bar {
  position: fixed; top:0; left:0; right:0; height:52px;
  display:flex; align-items:center; justify-content:space-between;
  padding:0 16px;
  background: var(--card-bg,#fff);
  border-bottom: 1px solid var(--border-color,rgba(0,0,0,0.08));
  z-index:1000;
}

body.mobile-mode .mob-back-btn {
  width:38px; height:38px; border-radius:50%; border:none;
  background:transparent; color:var(--text-primary,#1a1a2e);
  font-size:1.3rem; cursor:pointer;
  display:flex; align-items:center; justify-content:center;
}
body.mobile-mode .mob-back-btn:active { background:rgba(0,0,0,0.06); }

body.mobile-mode .mob-top-title {
  font-size:1rem; font-weight:600; color:var(--text-primary,#1a1a2e);
  overflow:hidden; text-overflow:ellipsis; white-space:nowrap;
}

body.mobile-mode main,
body.mobile-mode .container,
body.mobile-mode [class*="max-w"] {
  padding-left:12px!important; padding-right:12px!important;
  max-width:100%!important; padding-top:60px!important;
}

/* ========== 移动端弹窗优化 ========== */
.mobile-mode .modal-overlay {
  position: fixed !important;
  inset: 0 !important;
  z-index: 2000 !important;
  background: rgba(10,10,20,0.78) !important;
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  display: none !important;
  align-items: flex-end !important;
  justify-content: center !important;
  padding: 0 !important;
  animation: mobModalFade .2s ease-out;
}
.mobile-mode .modal-overlay.open { display: flex !important; }

.mobile-mode .modal-card {
  background: var(--mob-card) !important;
  border: 1px solid var(--mob-border) !important;
  border-radius: 20px 20px 8px 8px !important;
  padding: 20px 16px 24px !important;
  width: 100% !important;
  max-width: 100% !important;
  margin: 0 !important;
  position: relative !important;
  animation: mobModalSlideUp .3s cubic-bezier(0.16,1,0.3,1) !important;
  max-height: 90vh !important;
  overflow-y: auto !important;
  -webkit-overflow-scrolling: touch;
}

.mobile-mode .modal-close {
  position: absolute !important;
  top: 8px !important;
  right: 8px !important;
  width: 44px !important;
  height: 44px !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  font-size: 1.4rem !important;
  color: var(--mob-text-muted) !important;
  background: transparent !important;
  border: none !important;
  border-radius: 50% !important;
  cursor: pointer;
  transition: background .2s, color .2s;
  -webkit-tap-highlight-color: transparent;
}
.mobile-mode .modal-close:active {
  background: rgba(128,128,128,0.15) !important;
}

.mobile-mode .modal-card h2,
.mobile-mode .modal-card h3 {
  font-size: 1.15rem !important;
  padding-right: 40px !important;
  margin-top: 0 !important;
}

.mobile-mode .modal-card input[type="email"],
.mobile-mode .modal-card input[type="password"],
.mobile-mode .modal-card input[type="text"] {
  font-size: 16px !important;
  padding: 12px 14px !important;
  border-radius: 10px !important;
}

.mobile-mode .modal-card button[type="submit"],
.mobile-mode .modal-card .btn,
.mobile-mode .modal-card .modal-tab {
  min-height: 44px !important;
  font-size: 1rem !important;
  border-radius: 10px !important;
}

.mobile-mode .modal-tabs {
  display: flex !important;
  gap: 6px !important;
  margin-bottom: 16px !important;
  overflow-x: auto !important;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}
.mobile-mode .modal-tabs::-webkit-scrollbar { display: none; }

.mobile-mode .modal-tab {
  flex-shrink: 0 !important;
  padding: 8px 14px !important;
  font-size: .85rem !important;
  border-radius: 8px !important;
}

body.mobile-mode.modal-open {
  overflow: hidden !important;
  position: fixed !important;
  width: 100% !important;
}

@keyframes mobModalFade {
  from { opacity: 0; }
  to   { opacity: 1; }
}
@keyframes mobModalSlideUp {
  from { transform: translateY(100%); opacity: 0.8; }
  to   { transform: translateY(0);    opacity: 1; }
}

@media (orientation: landscape) {
  .mobile-mode .modal-overlay {
    align-items: center !important;
    padding: 16px !important;
  }
  .mobile-mode .modal-card {
    border-radius: 16px !important;
    max-width: 420px !important;
    max-height: 85vh !important;
    animation: mobModalFadeIn .25s ease-out !important;
  }
  @keyframes mobModalFadeIn {
    from { opacity:0; transform:scale(0.95); }
    to   { opacity:1; transform:scale(1); }
  }
}

/* ========== 手机端弹窗：@media 直接覆盖（最稳） ========== */
@media (max-width: 768px) {
  .modal-overlay {
    background: rgba(10,10,20,0.82) !important;
    backdrop-filter: blur(3px) !important;
    -webkit-backdrop-filter: blur(3px) !important;
    align-items: flex-end !important;
    padding: 0 !important;
  }
  .modal-overlay.open {
    display: flex !important;
  }
  .modal-card {
    background: #1a1a2e !important;
    border: 1px solid rgba(255,255,255,0.12) !important;
    border-radius: 20px 20px 8px 8px !important;
    padding: 20px 16px 28px !important;
    width: 100% !important;
    max-width: 100% !important;
    margin: 0 !important;
    border-radius: 20px 20px 0 0 !important;
    animation: mobSlideUp .3s cubic-bezier(0.16,1,0.3,1) !important;
    max-height: 92vh !important;
    overflow-y: auto !important;
  }
  .modal-close {
    top: 10px !important;
    right: 10px !important;
    width: 44px !important;
    height: 44px !important;
    display: flex !important;
    align-items: center !important;
    justify-content: center !important;
    font-size: 1.4rem !important;
  }
  .modal-card h2, .modal-card h3 {
    font-size: 1.1rem !important;
    padding-right: 44px !important;
  }
  /* 锁背景滚动 */
  body.modal-open { overflow: hidden !important; }
}

@media (max-width: 768px) and (orientation: landscape) {
  .modal-overlay {
    align-items: center !important;
    padding: 12px !important;
  }
  .modal-card {
    border-radius: 16px !important;
    max-width: 420px !important;
    max-height: 88vh !important;
  }
}

@keyframes mobSlideUp {
  from { transform: translateY(100%); }
  to   { transform: translateY(0); }
}