/* MeowMint - 猫薄荷英语 CSS 设计系统 */

/* ========== 1. CSS 变量 ========== */
:root {
  /* ===================== 品牌色 ===================== */
  --color-primary-50: #f0fdf4;
  --color-primary-100: #dcfce7;
  --color-primary-200: #bbf7d0;
  --color-primary-300: #86efac;
  --color-primary: #4ADE7B;
  --color-primary-500: #22c55e;
  --color-primary-600: #16a34a;
  --color-primary-700: #15803d;
  --color-primary-rgb: 74, 222, 123;
  --color-on-primary: #1a1a2e;

  /* ===================== 功能色 ===================== */
  --color-success: #10B981;
  --color-success-tint: rgba(16, 185, 129, 0.10);
  --color-warning: #F59E0B;
  --color-warning-tint: rgba(245, 158, 11, 0.10);
  --color-error: #EF4444;
  --color-error-tint: rgba(239, 68, 68, 0.10);
  --color-info: #3B82F6;
  --color-info-tint: rgba(59, 130, 246, 0.10);

  /* ===================== 语法术语辅助色 ===================== */
  --color-pronoun: rgb(139, 69, 19);
  --color-pronoun-light: rgb(245, 230, 211);
  --color-verb: rgb(34, 139, 34);
  --color-verb-light: rgb(230, 249, 230);
  --color-adjective: rgb(128, 0, 128);
  --color-adjective-light: rgb(243, 230, 243);
  --color-preposition: rgb(128, 128, 0);
  --color-preposition-light: rgb(245, 245, 230);
  --color-article: rgb(70, 130, 180);
  --color-article-light: rgb(230, 240, 248);
  --color-noun: rgb(220, 20, 60);
  --color-noun-light: rgb(249, 230, 230);

  /* ===================== 难度标签色 ===================== */
  --difficulty-entry-text: #047857;
  --difficulty-entry-surface: rgba(16, 185, 129, 0.20);
  --difficulty-entry-border: rgba(16, 185, 129, 0.46);
  --difficulty-basic-text: #1D4ED8;
  --difficulty-basic-surface: rgba(59, 130, 246, 0.18);
  --difficulty-basic-border: rgba(59, 130, 246, 0.42);
  --difficulty-medium-text: #B45309;
  --difficulty-medium-surface: rgba(245, 158, 11, 0.20);
  --difficulty-medium-border: rgba(245, 158, 11, 0.46);
  --difficulty-hard-text: #C2410C;
  --difficulty-hard-surface: rgba(249, 115, 22, 0.20);
  --difficulty-hard-border: rgba(249, 115, 22, 0.46);
  --difficulty-advanced-text: #6D28D9;
  --difficulty-advanced-surface: rgba(139, 92, 246, 0.20);
  --difficulty-advanced-border: rgba(139, 92, 246, 0.46);
  --difficulty-unknown-text: #475569;
  --difficulty-unknown-surface: rgba(100, 116, 139, 0.16);
  --difficulty-unknown-border: rgba(100, 116, 139, 0.34);

  /* ===================== 文字色 ===================== */
  --text-primary: #111827;
  --text-secondary: #6B7280;
  --text-tertiary: #9CA3AF;
  --text-disabled: #D1D5DB;
  --text-inverse: #FFFFFF;
  --text-on-primary: #1a1a2e;

  /* ===================== 背景色 ===================== */
  --bg-primary: #FFFFFF;
  --bg-secondary: #F9FAFB;
  --bg-tertiary: #F3F4F6;
  --bg-elevated: #FFFFFF;
  --bg-sunken: #F3F4F6;

  /* ===================== 边框 ===================== */
  --border-default: #E5E7EB;
  --border-subtle: #F3F4F6;
  --border-strong: #9CA3AF;
  --border-focus: #4ADE7B;

  /* ===================== 交互 tint ===================== */
  --color-primary-tint-10: rgba(74, 222, 123, 0.10);
  --color-primary-tint-15: rgba(74, 222, 123, 0.15);
  --color-primary-tint-30: rgba(74, 222, 123, 0.30);

  /* ===================== 遮罩 & 阴影 ===================== */
  --overlay-bg: rgba(0, 0, 0, 0.50);
  --shadow-color: rgba(0, 0, 0, 0.08);
  --shadow-primary: rgba(74, 222, 123, 0.30);
  --shadow-sm: 0 1px 4px var(--shadow-color);
  --shadow-md: 0 4px 12px var(--shadow-color);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-btn: 0 2px 8px var(--shadow-primary);
  --shadow-btn-hover: 0 4px 12px rgba(74, 222, 123, 0.40);
  --shadow-card-hover: 0 8px 24px rgba(74, 222, 123, 0.15);

  /* ===================== 过渡 ===================== */
  --transition-fast: 150ms ease;
  --transition-normal: 300ms ease;
  --transition-slow: 500ms ease;
  --transition-spring: 500ms cubic-bezier(0.34, 1.56, 0.64, 1);

  /* ===================== 字体 ===================== */
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Hiragino Sans GB", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-display: 'Outfit', var(--font-sans);
  --font-mono: 'JetBrains Mono', monospace;

  /* ===================== 字号 ===================== */
  --text-xs: 0.75rem;
  --text-sm: 0.875rem;
  --text-base: 1rem;
  --text-lg: 1.125rem;
  --text-xl: 1.25rem;
  --text-2xl: 1.5rem;
  --text-3xl: 1.875rem;
  --text-4xl: 2.25rem;
  --text-5xl: 3rem;

  /* ===================== 行高 ===================== */
  --leading-tight: 1.2;
  --leading-normal: 1.5;
  --leading-relaxed: 1.75;

  /* ===================== 间距 ===================== */
  --space-0: 0;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;

  /* ===================== 圆角 ===================== */
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-2xl: 20px;
  --radius-full: 9999px;
}

/* 深色模式 */
[data-theme="dark"] {
  /* ===================== 品牌色（深色模式适配） ===================== */
  --color-primary-50: rgba(74, 222, 123, 0.08);
  --color-primary-100: rgba(74, 222, 123, 0.12);
  --color-primary-200: rgba(74, 222, 123, 0.20);
  --color-primary-300: #86efac;
  --color-primary: #4ADE7B;
  --color-primary-500: #4ADE7B;
  --color-primary-600: #6ee7a0;
  --color-primary-700: #86efac;
  --color-on-primary: #1a1a2e;

  /* ===================== 功能色（深色更亮，对比度更高） ===================== */
  --color-success: #34D399;
  --color-success-tint: rgba(52, 211, 153, 0.15);
  --color-warning: #FBBF24;
  --color-warning-tint: rgba(251, 191, 36, 0.15);
  --color-error: #F87171;
  --color-error-tint: rgba(248, 113, 113, 0.15);
  --color-info: #60A5FA;
  --color-info-tint: rgba(96, 165, 250, 0.15);

  /* ===================== 语法术语辅助色（深色模式，提高亮度） ===================== */
  --color-pronoun: rgb(210, 180, 140);
  --color-pronoun-light: rgb(58, 42, 26);
  --color-verb: rgb(144, 238, 144);
  --color-verb-light: rgb(26, 42, 26);
  --color-adjective: rgb(218, 112, 214);
  --color-adjective-light: rgb(42, 26, 42);
  --color-preposition: rgb(218, 165, 32);
  --color-preposition-light: rgb(42, 42, 26);
  --color-article: rgb(135, 206, 235);
  --color-article-light: rgb(26, 42, 58);
  --color-noun: rgb(255, 107, 107);
  --color-noun-light: rgb(42, 26, 26);

  /* ===================== 难度标签色 ===================== */
  --difficulty-entry-text: #4ADE7B;
  --difficulty-entry-surface: rgba(74, 222, 123, 0.17);
  --difficulty-entry-border: rgba(74, 222, 123, 0.46);
  --difficulty-basic-text: #7CC2FF;
  --difficulty-basic-surface: rgba(124, 194, 255, 0.16);
  --difficulty-basic-border: rgba(124, 194, 255, 0.42);
  --difficulty-medium-text: #F4C95D;
  --difficulty-medium-surface: rgba(244, 201, 93, 0.17);
  --difficulty-medium-border: rgba(244, 201, 93, 0.46);
  --difficulty-hard-text: #FF9F43;
  --difficulty-hard-surface: rgba(255, 159, 67, 0.17);
  --difficulty-hard-border: rgba(255, 159, 67, 0.46);
  --difficulty-advanced-text: #B58CFF;
  --difficulty-advanced-surface: rgba(181, 140, 255, 0.18);
  --difficulty-advanced-border: rgba(181, 140, 255, 0.46);
  --difficulty-unknown-text: #CBD5E1;
  --difficulty-unknown-surface: rgba(148, 163, 184, 0.16);
  --difficulty-unknown-border: rgba(148, 163, 184, 0.36);

  /* ===================== 文字色 ===================== */
  --text-primary: #F9FAFB;
  --text-secondary: #9CA3AF;
  --text-tertiary: #6B7280;
  --text-disabled: #4B5563;
  --text-inverse: #111827;
  --text-on-primary: #1a1a2e;

  /* ===================== 背景色 ===================== */
  --bg-primary: #1F2937;
  --bg-secondary: #111827;
  --bg-tertiary: #374151;
  --bg-elevated: #1F2937;
  --bg-sunken: #0D1117;

  /* ===================== 边框 ===================== */
  --border-default: #374151;
  --border-subtle: #1F2937;
  --border-strong: #6B7280;
  --border-focus: #4ADE7B;

  /* ===================== 遮罩 & 阴影（深色更重） ===================== */
  --overlay-bg: rgba(0, 0, 0, 0.70);
  --shadow-color: rgba(0, 0, 0, 0.30);
  --shadow-primary: rgba(74, 222, 123, 0.20);
  --shadow-sm: 0 1px 4px var(--shadow-color);
  --shadow-md: 0 4px 12px var(--shadow-color);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.5);
  --shadow-btn: 0 2px 8px var(--shadow-primary);
  --shadow-btn-hover: 0 4px 12px rgba(74, 222, 123, 0.30);
  --shadow-card-hover: 0 8px 24px rgba(74, 222, 123, 0.12);
}

[data-theme="dark"] .modal {
  border: 1px solid var(--border-strong);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: 1.6;
  color: var(--text-primary);
  background-color: var(--bg-secondary);
  min-height: 100dvh;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

body.auth-pending {
  visibility: hidden;
}

body.shell-pending {
  visibility: hidden;
}

body.auth-ready:not(.shell-pending),
body.shell-ready {
  visibility: visible;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

input, textarea, select {
  font-family: inherit;
  font-size: inherit;
}

/* ========== 3. 布局容器 ========== */
.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 640px) {
  .container { max-width: 640px; }
}

@media (min-width: 768px) {
  .container { max-width: 768px; }
}

@media (min-width: 1024px) {
  .container {
    max-width: 1024px;
    padding: 0 var(--space-6);
  }
}

@media (min-width: 1280px) {
  .container { max-width: 1280px; }
}

.page {
  min-height: 100dvh;
  padding-bottom: 80px;
}

@media (min-width: 1024px) {
  .page {
    padding-bottom: 0;
    padding-left: 260px;
  }
}

/* ========== 4. 头部导航 ========== */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border-default);
  height: 64px;
  display: flex;
  align-items: center;
  transition: background-color var(--transition-normal);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 var(--space-4);
}

.header__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
}

.header__logo svg {
  width: 32px;
  height: 32px;
}

.header__search {
  display: none;
  flex: 1;
  max-width: 400px;
  margin: 0 var(--space-6);
}

@media (min-width: 768px) {
  .header__search {
    display: block;
  }
}

.header__search-input {
  width: 100%;
  height: 40px;
  padding: 0 var(--space-4) 0 44px;
  background: var(--bg-tertiary);
  border: 1px solid transparent;
  border-radius: var(--radius-full);
  font-size: var(--text-sm);
  color: var(--text-primary);
  transition: all var(--transition-fast);
}

.header__search-input::placeholder {
  color: var(--text-disabled);
}

.header__search-input:focus {
  outline: none;
  border-color: var(--color-primary);
  background: var(--bg-primary);
}

.header__search-wrapper {
  position: relative;
}

.header__search-icon {
  position: absolute;
  left: var(--space-4);
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  color: var(--text-disabled);
}

.header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-2);
}

.header__icon-btn {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-lg);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
  position: relative;
}

.header__icon-btn:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.header__icon-btn svg {
  width: 22px;
  height: 22px;
}

.header__notification-badge {
  position: absolute;
  top: 6px;
  right: 6px;
  width: 8px;
  height: 8px;
  background: var(--color-error);
  border-radius: var(--radius-full);
}

.header__avatar {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-on-primary);
  font-weight: 600;
  font-size: var(--text-sm);
  cursor: pointer;
  transition: transform var(--transition-fast);
  border: none;
  padding: 0;
  font-family: inherit;
}

.header__avatar:hover {
  transform: scale(1.05);
}

/* ========== 5. 侧边导航 ========== */
.sidebar {
  display: none;
  position: fixed;
  left: 0;
  top: 0;
  bottom: 0;
  width: 260px;
  background: var(--bg-elevated);
  border-right: 1px solid var(--border-default);
  padding: var(--space-4);
  z-index: 90;
  overflow-y: auto;
  transition: background-color var(--transition-normal);
  flex-direction: column;
}

@media (min-width: 1024px) {
  .sidebar {
    display: flex;
  }
}

.sidebar__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-family: var(--font-display);
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-8);
}

.sidebar__logo svg {
  width: 36px;
  height: 36px;
}

.sidebar__logo-img {
  width: 36px;
  height: 36px;
  border-radius: var(--radius-lg);
  object-fit: cover;
}

.sidebar__nav {
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.sidebar__item {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  font-weight: 500;
  transition: all var(--transition-fast);
  background: none;
  border: none;
  cursor: pointer;
  width: 100%;
  text-align: left;
  font-size: inherit;
  font-family: inherit;
  transform: translateX(0);
  position: relative;
  overflow: hidden;
}

.sidebar__item::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: var(--color-primary);
  transform: scaleY(0);
  transition: transform var(--transition-fast);
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
}

.sidebar__item:hover::before {
  transform: scaleY(1);
}

.sidebar__item--active::before {
  transform: scaleY(1);
}

.sidebar__item:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  transform: translateX(4px);
  box-shadow: var(--shadow-sm);
}

.sidebar__item--active {
  background: var(--bg-tertiary);
  color: var(--text-primary);
  font-weight: 600;
}

.sidebar__item svg {
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.sidebar__item:hover svg {
  transform: scale(1.1);
  color: var(--text-primary);
}

.sidebar__item--active svg {
  transform: scale(1.1);
  color: var(--text-primary);
}

.sidebar__divider {
  height: 1px;
  background: var(--border-default);
  margin: var(--space-4) 0;
}

.sidebar__section-title {
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--text-disabled);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding: var(--space-2) var(--space-4);
  margin-top: var(--space-2);
  transition: color var(--transition-normal);
}

/* ========== 6. 用户信息 ========== */
.sidebar__user {
  margin-top: auto;
  padding-top: var(--space-4);
  transition: border-color var(--transition-normal);
}

.sidebar__user-btn {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-lg);
  background: none;
  border: none;
  cursor: pointer;
  width: 100%;
  text-align: left;
  font-size: inherit;
  font-family: inherit;
  color: var(--text-primary);
  transition: all var(--transition-fast);
  position: relative;
}

.sidebar__user-btn:hover {
  background: var(--bg-tertiary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.sidebar__user-btn--active {
  background: var(--bg-tertiary);
}

.sidebar__user-avatar {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.sidebar__user-btn:hover .sidebar__user-avatar {
  transform: scale(1.05);
}

.sidebar__user-avatar-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  border-radius: var(--radius-full);
}

.sidebar__user-avatar-placeholder {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: var(--text-base);
  color: var(--color-on-primary);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  transition: all var(--transition-fast);
}

.sidebar__user-name {
  flex: 1;
  font-weight: 500;
  color: var(--text-primary);
  transition: color var(--transition-normal);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.sidebar__user-arrow {
  width: 16px;
  height: 16px;
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.sidebar__user-btn--active .sidebar__user-arrow {
  transform: rotate(180deg);
}

.sidebar__user-menu {
  position: absolute;
  bottom: 100%;
  left: var(--space-4);
  right: var(--space-4);
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  display: grid;
  gap: 0;
  padding: 18px var(--space-3);
  margin-bottom: var(--space-2);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-fast);
  z-index: 100;
}

.sidebar__user-menu--active {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.sidebar__user-menu-item {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  justify-content: flex-start;
  min-height: 52px;
  padding: 13px 18px;
  border-radius: var(--radius-lg);
  background: none;
  border: none;
  cursor: pointer;
  width: 100%;
  text-align: left;
  font-size: inherit;
  font-family: inherit;
  color: var(--text-primary);
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.sidebar__user-menu-item:hover {
  background: var(--bg-tertiary);
  transform: none;
}

.sidebar__user-menu-item--danger {
  color: var(--color-error);
  margin-top: var(--space-2);
}

.sidebar__user-menu-item--danger:hover {
  background: var(--color-error-tint);
}

.sidebar__user-menu-item svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  transition: transform var(--transition-fast);
}

.sidebar__user-menu-item:hover svg {
  transform: scale(1.1);
}

/* ========== 7. 底部导航 ========== */
.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 64px;
  background: var(--bg-elevated);
  border-top: 1px solid var(--border-default);
  display: flex;
  justify-content: space-around;
  align-items: center;
  padding: 0 var(--space-2);
  padding-bottom: env(safe-area-inset-bottom, 0);
  z-index: 100;
  transition: background-color var(--transition-normal);
}

@media (min-width: 1024px) {
  .bottom-nav {
    display: none;
  }
}

.bottom-nav__item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: var(--space-2) var(--space-3);
  color: var(--text-secondary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  min-width: 64px;
  background: none;
  border: none;
  cursor: pointer;
  font-size: inherit;
  font-family: inherit;
}

.bottom-nav__item:hover {
  color: var(--text-primary);
}

.bottom-nav__item--active {
  color: var(--color-primary);
}

.bottom-nav__item svg {
  width: 24px;
  height: 24px;
}

.bottom-nav__label {
  font-size: var(--text-xs);
  font-weight: 500;
}

/* ========== 7. 按钮 ========== */
.btn,
.btn-primary,
.btn-secondary,
.btn-ghost,
.btn-danger,
.btn--primary,
.btn--secondary,
.btn--ghost,
.btn--danger {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-weight: 600;
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  cursor: pointer;
  border: none;
  white-space: nowrap;
  font-family: inherit;
  padding: 0 var(--space-5);
  height: 40px;
}

.btn:focus-visible,
.btn-primary:focus-visible,
.btn-secondary:focus-visible,
.btn-ghost:focus-visible,
.btn-danger:focus-visible,
.btn--primary:focus-visible,
.btn--secondary:focus-visible,
.btn--ghost:focus-visible,
.btn--danger:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.btn:disabled,
.btn-primary:disabled,
.btn-secondary:disabled,
.btn-ghost:disabled,
.btn-danger:disabled,
.btn--primary:disabled,
.btn--secondary:disabled,
.btn--ghost:disabled,
.btn--danger:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  pointer-events: none;
}

/* 按钮尺寸 */
.btn-sm,
.btn--sm {
  height: 32px !important;
  padding: 0 var(--space-4) !important;
  font-size: var(--text-sm) !important;
}

.btn-md,
.btn--md {
  height: 40px !important;
  padding: 0 var(--space-5) !important;
  font-size: var(--text-sm) !important;
}

.btn-lg,
.btn--lg {
  height: 48px !important;
  padding: 0 var(--space-6) !important;
  font-size: var(--text-base) !important;
}

.btn-xl,
.btn--xl {
  height: 56px !important;
  padding: 0 var(--space-8) !important;
  font-size: var(--text-lg) !important;
}

/* 按钮变体 */
.btn-primary,
.btn--primary {
  background: var(--color-primary);
  color: var(--color-on-primary);
  box-shadow: var(--shadow-btn);
}

.btn-primary:hover:not(:disabled),
.btn--primary:hover:not(:disabled) {
  background: var(--color-primary-600);
  transform: translateY(-1px);
  box-shadow: var(--shadow-btn-hover);
}

.btn-primary:active:not(:disabled),
.btn--primary:active:not(:disabled) {
  transform: translateY(0);
}

.btn-secondary,
.btn--secondary {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-default);
  font-weight: 600;
  transition: all var(--transition-fast);
}

.btn-secondary:hover:not(:disabled),
.btn--secondary:hover:not(:disabled) {
  background: var(--bg-tertiary);
  border-color: var(--border-strong);
  color: var(--text-primary);
  transform: translateY(-1px);
}

.btn-ghost,
.btn--ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid var(--border-default);
}

.btn-ghost:hover:not(:disabled),
.btn--ghost:hover:not(:disabled) {
  background: var(--bg-tertiary);
  border-color: var(--border-strong);
  color: var(--text-primary);
}

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

.btn-danger:hover:not(:disabled),
.btn--danger:hover:not(:disabled) {
  background: #DC2626;
}

.btn-icon {
  width: 40px;
  height: 40px;
  padding: 0;
}

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

.btn-icon.btn-lg {
  width: 48px;
  height: 48px;
}

.btn svg {
  width: 20px;
  height: 20px;
}

/* ========== 8. 卡片 ========== */
.card {
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  border: 1px solid var(--border-default);
  transition: all var(--transition-normal);
}

.card:hover {
  border-color: var(--color-primary-300);
}

.card--interactive:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-2px);
}

/* ========== 探照灯卡片 ========== */
.card-spotlight {
  position: relative;
  overflow: hidden;
  cursor: pointer;
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-default);
  transition: all var(--transition-normal);
}

.card-spotlight::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: radial-gradient(
    300px circle at var(--mouse-x, 0px) var(--mouse-y, 0px),
    rgba(var(--color-primary-rgb), 0.6) 0%,
    rgba(var(--color-primary-rgb), 0.4) 30%,
    transparent 40%
  );
  opacity: 0;
  transition: opacity var(--transition-normal);
  pointer-events: none;
  z-index: 1;
}

.card-spotlight::after {
  content: '';
  position: absolute;
  top: var(--mouse-y, 50%);
  left: var(--mouse-x, 50%);
  width: 200px;
  height: 200px;
  background: radial-gradient(
    circle,
    rgba(var(--color-primary-rgb), 0.3) 0%,
    rgba(var(--color-primary-rgb), 0.1) 50%,
    transparent 70%
  );
  border-radius: 50%;
  transform: translate(-50%, -50%);
  opacity: 0;
  transition: opacity var(--transition-normal);
  pointer-events: none;
  z-index: 0;
  filter: blur(20px);
}

.card-spotlight:hover::before {
  opacity: 1;
}

.card-spotlight:hover::after {
  opacity: 1;
}

.card-spotlight__content {
  position: relative;
  z-index: 2;
  background: var(--bg-elevated);
  margin: 1px;
  border-radius: calc(var(--radius-xl) - 1px);
  padding: var(--space-6);
  transition: all var(--transition-normal);
}

.card-spotlight:hover {
  border-color: var(--border-default);
  transform: translateY(-2px);
  box-shadow: var(--shadow-card-hover);
}

.card-spotlight:hover .card-spotlight__content {
  background: var(--bg-primary);
}

/* 减少动画偏好时的降级方案 */
@media (prefers-reduced-motion: reduce) {
  .card-spotlight::before {
    display: none;
  }
  
  .card-spotlight__content {
    margin: 0;
    border-radius: var(--radius-xl);
  }
}

.card__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-4);
}

.card__title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--text-primary);
}

.card__subtitle {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-top: var(--space-1);
}

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

.card__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--border-default);
}

/* ========== 9. 徽章 ========== */
.badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-1);
  padding: 4px 10px;
  font-size: var(--text-xs);
  font-weight: 600;
  border-radius: var(--radius-full);
}

.badge--primary {
  background: var(--color-primary-tint-15);
  color: var(--color-primary-600);
}

[data-theme="dark"] .badge--primary {
  color: var(--color-primary);
}

.badge--success {
  background: var(--color-success-tint);
  color: var(--color-success);
}

.badge--warning {
  background: var(--color-warning-tint);
  color: var(--color-warning);
}

.badge--error {
  background: var(--color-error-tint);
  color: var(--color-error);
}

.badge--info {
  background: var(--color-info-tint);
  color: var(--color-info);
}

/* ========== 10. 进度条 ========== */
.progress-bar {
  height: 8px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
  overflow: hidden;
}

.progress-bar__fill {
  height: 100%;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-300));
  border-radius: var(--radius-full);
  transition: width 0.5s ease;
}

.progress-ring {
  transform: rotate(-90deg);
}

.progress-ring__circle {
  stroke: var(--bg-tertiary);
  fill: none;
}

.progress-ring__progress {
  stroke: var(--color-primary);
  fill: none;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.5s ease;
}

/* ========== 11. 练习卡片 ========== */
.practice-card {
  position: relative;
  overflow: hidden;
  cursor: pointer;
}

.practice-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-300));
  pointer-events: none;
}

.practice-card__icon {
  width: 48px;
  height: 48px;
  background: var(--color-primary-50);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-2xl);
  margin-bottom: var(--space-4);
}

.practice-card__title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.practice-card__desc {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
}

.practice-card__meta {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

.practice-card__meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.practice-card__meta-item svg {
  width: 16px;
  height: 16px;
}

.practice-card__difficulty {
  position: absolute;
  top: var(--space-4);
  right: var(--space-4);
  padding: 4px 12px;
  border-radius: var(--radius-full);
  font-size: var(--text-xs);
  font-weight: 600;
}

.practice-card__difficulty--easy {
  background: var(--color-success-tint);
  color: var(--color-success);
}

.practice-card__difficulty--medium {
  background: var(--color-warning-tint);
  color: var(--color-warning);
}

.practice-card__difficulty--hard {
  background: var(--color-error-tint);
  color: var(--color-error);
}

/* ========== 12. 表单元素 ========== */
.form-group {
  margin-bottom: var(--space-5);
}

.form-label {
  display: block;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.form-input {
  width: 100%;
  height: 48px;
  padding: 0 var(--space-4);
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  font-size: var(--text-base);
  color: var(--text-primary);
  transition: all var(--transition-fast);
}

.form-input::placeholder {
  color: var(--text-disabled);
}

.form-input:hover:not(:disabled):not(:focus) {
  border-color: var(--color-primary-300);
}

.form-input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-tint-15);
}

.form-input:disabled {
  background: var(--bg-tertiary);
  cursor: not-allowed;
}

.form-input--error {
  border-color: var(--color-error);
}

.form-input--error:focus {
  box-shadow: 0 0 0 4px var(--color-error-tint);
}

.form-error {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  margin-top: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-error);
}

.form-error svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* ========== 13. 模态框 ========== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: var(--overlay-bg);
  backdrop-filter: blur(4px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  z-index: 1000;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

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

.modal {
  background: var(--bg-elevated);
  border-radius: var(--radius-2xl);
  width: 100%;
  max-width: 480px;
  max-height: 90vh;
  overflow: auto;
  transform: scale(0.9) translateY(20px);
  transition: transform var(--transition-normal);
  border: 1px solid var(--border-default);
}

.modal-overlay--active .modal {
  transform: scale(1) translateY(0);
}

.modal__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-6);
  border-bottom: 1px solid var(--border-default);
}

.modal__title {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--text-primary);
}

.modal__close {
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-md);
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.modal__close:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.modal__body {
  padding: var(--space-6);
}

.modal__footer {
  display: flex;
  gap: var(--space-3);
  justify-content: flex-end;
  align-items: center;
  flex-wrap: wrap;
  padding: var(--space-6);
  border-top: 1px solid var(--border-default);
}

.modal__footer .btn,
.modal__footer .btn-primary,
.modal__footer .btn-secondary,
.modal__footer .btn-ghost,
.modal__footer .btn-danger,
.modal__footer .btn--primary,
.modal__footer .btn--secondary,
.modal__footer .btn--ghost,
.modal__footer .btn--danger {
  min-width: 96px;
}

/* ========== 14. 统计卡片 ========== */
.stat-card {
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  padding: var(--space-5);
  border: 1px solid var(--border-default);
  transition: all var(--transition-normal);
}

.stat-card__icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--space-4);
}

.stat-card__icon--primary {
  background: var(--color-primary-tint-15);
  color: var(--color-primary);
}

.stat-card__icon--success {
  background: var(--color-success-tint);
  color: var(--color-success);
}

.stat-card__icon--warning {
  background: var(--color-warning-tint);
  color: var(--color-warning);
}

.stat-card__icon--info {
  background: var(--color-info-tint);
  color: var(--color-info);
}

.stat-card__icon svg {
  width: 22px;
  height: 22px;
}

.stat-card__value {
  font-size: var(--text-3xl);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1;
}

.stat-card__label {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-top: var(--space-2);
}

.stat-card__trend {
  display: flex;
  align-items: center;
  gap: var(--space-1);
  font-size: var(--text-sm);
  font-weight: 500;
  margin-top: var(--space-2);
}

.stat-card__trend--up {
  color: var(--color-success);
}

.stat-card__trend--down {
  color: var(--color-error);
}

/* ========== 15. 成就徽章 ========== */
.achievement-badge {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4);
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  border: 1px solid var(--border-default);
  text-align: center;
  transition: all var(--transition-normal);
}

.achievement-badge:hover {
  border-color: var(--color-primary-300);
  transform: translateY(-2px);
}

.achievement-badge--unlocked {
  border-color: var(--color-primary);
  background: linear-gradient(135deg, var(--bg-elevated), var(--color-primary-50));
}

.achievement-badge__icon {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-full);
  background: var(--bg-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-3xl);
}

.achievement-badge--unlocked .achievement-badge__icon {
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  box-shadow: var(--shadow-btn);
}

.achievement-badge__title {
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-primary);
}

.achievement-badge__desc {
  font-size: var(--text-xs);
  color: var(--text-secondary);
}

/* ========== 16. 打卡连续徽章 ========== */
.streak-badge {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-4);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  color: var(--color-on-primary);
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: var(--text-sm);
  box-shadow: var(--shadow-btn);
}

.streak-badge__fire {
  font-size: var(--text-lg);
}

/* ========== 17. 录音区域 ========== */
.record-area {
  background: var(--bg-elevated);
  border: 2px dashed var(--border-default);
  border-radius: var(--radius-2xl);
  padding: var(--space-12) var(--space-6);
  text-align: center;
  transition: all var(--transition-fast);
  cursor: pointer;
}

.record-area:hover {
  border-color: var(--color-primary);
  background: var(--color-primary-50);
}

.record-area--recording {
  border-color: var(--color-error);
  background: rgba(239, 68, 68, 0.05);
  border-style: solid;
}

.record-area__icon {
  width: 80px;
  height: 80px;
  margin: 0 auto var(--space-4);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-on-primary);
  transition: all var(--transition-fast);
}

.record-area:hover .record-area__icon {
  transform: scale(1.05);
  box-shadow: var(--shadow-btn-hover);
}

.record-area--recording .record-area__icon {
  background: var(--color-error);
  color: white;
  animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.1); }
}

.record-area__icon svg {
  width: 36px;
  height: 36px;
}

.record-area__text {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.record-area__hint {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

/* ========== 18. 波形动画 ========== */
.waveform {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 4px;
  height: 40px;
  margin: var(--space-4) 0;
}

.waveform__bar {
  width: 4px;
  height: 8px;
  background: var(--color-primary);
  border-radius: 2px;
  animation: waveform 0.5s ease-in-out infinite;
}

@keyframes waveform {
  0%, 100% { height: 8px; }
  50% { height: 32px; }
}

.waveform__bar:nth-child(1) { animation-delay: 0s; }
.waveform__bar:nth-child(2) { animation-delay: 0.1s; }
.waveform__bar:nth-child(3) { animation-delay: 0.2s; }
.waveform__bar:nth-child(4) { animation-delay: 0.3s; }
.waveform__bar:nth-child(5) { animation-delay: 0.4s; }
.waveform__bar:nth-child(6) { animation-delay: 0.5s; }
.waveform__bar:nth-child(7) { animation-delay: 0.6s; }

/* ========== 19. 评分环形 ========== */
.score-ring {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

.score-ring__svg {
  transform: rotate(-90deg);
}

.score-ring__circle-bg {
  fill: none;
  stroke: var(--bg-tertiary);
}

.score-ring__circle-progress {
  fill: none;
  stroke-linecap: round;
  transition: stroke-dashoffset 0.5s ease;
}

.score-ring--excellent .score-ring__circle-progress { stroke: var(--color-success); }
.score-ring--good .score-ring__circle-progress { stroke: var(--color-primary); }
.score-ring--fair .score-ring__circle-progress { stroke: var(--color-warning); }
.score-ring--poor .score-ring__circle-progress { stroke: var(--color-error); }

.score-ring__value {
  position: absolute;
  font-size: var(--text-3xl);
  font-weight: 700;
  color: var(--text-primary);
}

.score-ring__label {
  position: absolute;
  bottom: -8px;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--text-secondary);
  white-space: nowrap;
}

.score-ring--excellent .score-ring__label { color: var(--color-success); }
.score-ring--good .score-ring__label { color: var(--color-primary); }
.score-ring--fair .score-ring__label { color: var(--color-warning); }
.score-ring--poor .score-ring__label { color: var(--color-error); }

/* ========== 20. 空状态 ========== */
.empty-state {
  text-align: center;
  padding: var(--space-12) var(--space-6);
}

.empty-state__icon {
  width: 120px;
  height: 120px;
  margin: 0 auto var(--space-6);
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-primary);
  font-size: var(--text-4xl);
}

.empty-state__icon svg {
  width: 48px;
  height: 48px;
}

.empty-state__title {
  font-size: var(--text-xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.empty-state__desc {
  font-size: var(--text-base);
  color: var(--text-secondary);
  max-width: 400px;
  margin: 0 auto var(--space-6);
}

/* ========== 21. 分页 ========== */
.pagination {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  margin-top: var(--space-8);
}

.pagination__btn {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-lg);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-secondary);
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  transition: all var(--transition-fast);
}

.pagination__btn:hover:not(:disabled) {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.pagination__btn--active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: var(--color-on-primary);
}

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

.pagination__btn svg {
  width: 20px;
  height: 20px;
}

/* ========== 22. 标签页 ========== */
.tabs {
  display: flex;
  gap: var(--space-1);
  border-bottom: 1px solid var(--border-default);
  margin-bottom: var(--space-6);
  overflow-x: auto;
}

.tabs__item {
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-secondary);
  border-bottom: 2px solid transparent;
  transition: all var(--transition-fast);
  white-space: nowrap;
}

.tabs__item:hover {
  color: var(--text-primary);
}

.tabs__item--active {
  color: var(--color-primary);
  border-bottom-color: var(--color-primary);
}

/* ========== 23. 工具类 ========== */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.font-medium { font-weight: 500; }
.font-semibold { font-weight: 600; }
.font-bold { font-weight: 700; }

.text-primary { color: var(--text-primary); }
.text-secondary { color: var(--text-secondary); }
.text-tertiary { color: var(--text-tertiary); }
.text-disabled { color: var(--text-disabled); }
.text-success { color: var(--color-success); }
.text-warning { color: var(--color-warning); }
.text-error { color: var(--color-error); }

.bg-primary { background-color: var(--bg-primary); }
.bg-secondary { background-color: var(--bg-secondary); }
.bg-tertiary { background-color: var(--bg-tertiary); }
.bg-error-tint { background-color: var(--color-error-tint); }

.flex { display: flex; }
.flex-col { flex-direction: column; }
.items-center { align-items: center; }
.items-start { align-items: flex-start; }
.items-end { align-items: flex-end; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }
.justify-end { justify-content: flex-end; }
.flex-wrap { flex-wrap: wrap; }
.flex-1 { flex: 1; }
.gap-1 { gap: var(--space-1); }
.gap-2 { gap: var(--space-2); }
.gap-3 { gap: var(--space-3); }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.grid { display: grid; gap: var(--space-6); }
.grid-cols-1 { grid-template-columns: repeat(1, 1fr); }
.grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
.grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
.grid-cols-4 { grid-template-columns: repeat(4, 1fr); }

@media (min-width: 640px) {
  .sm\:grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 768px) {
  .md\:grid-cols-2 { grid-template-columns: repeat(2, 1fr); }
  .md\:grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
  .md\:flex-row { flex-direction: row; }
}

@media (min-width: 1024px) {
  .lg\:grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
  .lg\:grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
}

.w-full { width: 100%; }
.h-full { height: 100%; }

.mt-1 { margin-top: var(--space-1); }
.mt-2 { margin-top: var(--space-2); }
.mt-3 { margin-top: var(--space-3); }
.mt-4 { margin-top: var(--space-4); }
.mt-6 { margin-top: var(--space-6); }
.mt-8 { margin-top: var(--space-8); }
.mt-0 { margin-top: 0; }

.mb-1 { margin-bottom: var(--space-1); }
.mb-2 { margin-bottom: var(--space-2); }
.mb-3 { margin-bottom: var(--space-3); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }
.mb-8 { margin-bottom: var(--space-8); }

.p-3 { padding: var(--space-3); }
.p-4 { padding: var(--space-4); }
.p-6 { padding: var(--space-6); }
.p-8 { padding: var(--space-8); }
.pl-4 { padding-left: var(--space-4); }
.px-4 { padding-left: var(--space-4); padding-right: var(--space-4); }
.py-4 { padding-top: var(--space-4); padding-bottom: var(--space-4); }

.rounded-lg { border-radius: var(--radius-lg); }
.rounded-xl { border-radius: var(--radius-xl); }
.rounded-full { border-radius: var(--radius-full); }

.shadow-sm { box-shadow: var(--shadow-sm); }
.shadow-md { box-shadow: var(--shadow-md); }
.shadow-lg { box-shadow: var(--shadow-lg); }

.hidden { display: none; }
.block { display: block; }
.inline-flex { display: inline-flex; }

.overflow-hidden { overflow: hidden; }
.relative { position: relative; }
.absolute { position: absolute; }

.hidden-mobile { display: none; }
@media (min-width: 768px) {
  .hidden-mobile { display: inline-block; }
}

.border { border-width: 1px; }
.border-default { border-color: var(--border-default); }
.border-error { border-color: var(--color-error); }

.leading-relaxed { line-height: var(--leading-relaxed); }

/* ========== 24. 动画 ========== */
@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

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

@keyframes shake {
  0%, 100% { transform: translateX(0); }
  25% { transform: translateX(-8px); }
  75% { transform: translateX(8px); }
}

@keyframes successBounce {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(1.1); }
}

.animate-fade-in {
  animation: fadeIn var(--transition-normal) ease forwards;
}

.animate-slide-up {
  animation: slideUp var(--transition-normal) ease forwards;
}

.animate-shake {
  animation: shake 0.4s ease;
}

.animate-success {
  animation: successBounce 0.4s ease;
}

/* 减少动画偏好 */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* ========== 25. 滚动条美化 ========== */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-default);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-disabled);
}

/* ========== 26. 页面标题区 ========== */
.page-header {
  padding: var(--space-6) 0;
}

.page-header__greeting {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.page-header__subtitle {
  font-size: var(--text-base);
  color: var(--text-secondary);
}

.page-header__actions {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  margin-top: var(--space-4);
}

/* ========== 27. Section 标题 ========== */
.section {
  margin-bottom: var(--space-8);
}

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

.section__title {
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--text-primary);
}

.section__link {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--color-primary);
  display: flex;
  align-items: center;
  gap: var(--space-1);
  transition: all var(--transition-fast);
  background: none;
  border: none;
  cursor: pointer;
  padding: 0;
  font-family: inherit;
}

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

.section__link svg {
  width: 16px;
  height: 16px;
}

/* ========== 28. 列表项 ========== */
.list-item {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-elevated);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-default);
  transition: all var(--transition-fast);
  cursor: pointer;
}

.list-item:hover {
  border-color: var(--color-primary);
  transform: translateX(4px);
}

.list-item__icon {
  width: 44px;
  height: 44px;
  background: var(--color-primary-50);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  flex-shrink: 0;
}

.list-item__content {
  flex: 1;
  min-width: 0;
}

.list-item__title {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.list-item__subtitle {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

.list-item__action {
  color: var(--text-secondary);
  flex-shrink: 0;
}

.list-item__action svg {
  width: 20px;
  height: 20px;
}

/* ========== 29. 设置项 ========== */
.settings-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) 0;
  border-bottom: 1px solid var(--border-default);
}

.settings-item:last-child {
  border-bottom: none;
}

.settings-item__info {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.settings-item__icon {
  width: 40px;
  height: 40px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
}

.settings-item__icon svg {
  width: 20px;
  height: 20px;
}

.settings-item__title {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--text-primary);
}

.settings-item__desc {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

/* ========== 30. 开关 ========== */
.toggle {
  position: relative;
  width: 52px;
  height: 28px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.toggle--active {
  background: var(--color-primary);
}

.toggle__knob {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 24px;
  height: 24px;
  background: white;
  border-radius: var(--radius-full);
  box-shadow: var(--shadow-sm);
  transition: transform var(--transition-fast);
}

.toggle--active .toggle__knob {
  transform: translateX(24px);
}

/* ========== 31. 练习页面布局 ========== */
.practice-layout {
  display: grid;
  gap: var(--space-6);
  max-width: 800px;
  margin: 0 auto;
}

@media (min-width: 1024px) {
  .practice-layout {
    grid-template-columns: 1fr 300px;
    max-width: 1000px;
  }
}

.scene-info {
  text-align: center;
  padding: var(--space-6);
  background: linear-gradient(135deg, var(--color-primary-50), transparent);
  border-radius: var(--radius-xl);
  margin-bottom: var(--space-6);
}

@media (min-width: 1024px) {
  .scene-info {
    text-align: left;
    background: transparent;
    padding: 0;
  }
}

.scene-info__icon {
  font-size: 3rem;
  margin-bottom: var(--space-3);
}

.scene-info__title {
  font-size: var(--text-2xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.scene-info__desc {
  font-size: var(--text-lg);
  color: var(--text-secondary);
  margin-bottom: var(--space-3);
}

.sentence-box {
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  border: 1px solid var(--border-default);
  margin-bottom: var(--space-6);
}

.sentence-box__label {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.sentence-box__label svg {
  width: 18px;
  height: 18px;
}

.sentence-box__text {
  font-size: var(--text-xl);
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.6;
  margin-bottom: var(--space-4);
}

.sentence-box__phonetic {
  font-family: var(--font-mono);
  font-size: var(--text-base);
  color: var(--text-secondary);
  background: var(--bg-tertiary);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-lg);
}

.audio-player {
  background: var(--bg-tertiary);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  display: flex;
  align-items: center;
  gap: var(--space-4);
  margin-top: var(--space-4);
}

.audio-player__btn {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-on-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.audio-player__btn:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-btn-hover);
}

.audio-player__btn svg {
  width: 20px;
  height: 20px;
}

.audio-player__info {
  flex: 1;
}

.audio-player__name {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-primary);
}

.audio-player__duration {
  font-size: var(--text-xs);
  color: var(--text-secondary);
}

.translation-area {
  margin-bottom: var(--space-6);
}

.translation-area__label {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: var(--space-3);
}

.translation-area__input {
  width: 100%;
  min-height: 100px;
  padding: var(--space-4);
  background: var(--bg-primary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  font-size: var(--text-base);
  color: var(--text-primary);
  resize: vertical;
  transition: all var(--transition-fast);
}

.translation-area__input:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-tint-15);
}

.practice-tips {
  background: var(--color-primary-50);
  border-radius: var(--radius-lg);
  padding: var(--space-4);
  margin-top: var(--space-6);
}

.practice-tips__title {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--space-3);
}

.practice-tips__title svg {
  width: 18px;
  height: 18px;
}

.practice-tips__list {
  list-style: disc;
  padding-left: 1.5rem;
}

.practice-tips__item {
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-2);
}

.practice-tips__item:last-child {
  margin-bottom: 0;
}

/* ========== 32. 登录页样式 ========== */
.login-page {
  min-height: 100dvh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-6);
}

.login-container {
  width: 100%;
  max-width: 500px;
  text-align: center;
  padding: var(--space-12) var(--space-6);
}

.login-header {
  margin-bottom: var(--space-16);
}

.login-header__logo {
  margin-bottom: var(--space-8);
  display: inline-flex;
  align-items: center;
}

.login-header__logo svg {
  width: 64px;
  height: 64px;
  color: var(--color-primary);
  transition: transform var(--transition-normal);
}

.login-header__logo svg:hover {
  transform: scale(1.05);
}

.login-header__logo-img {
  width: 64px;
  height: 64px;
  border-radius: var(--radius-lg);
  object-fit: cover;
  transition: transform var(--transition-normal);
}

.login-header__logo-img:hover {
  transform: scale(1.05);
}

.login-header__brand {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  margin-left: var(--space-4);
  font-family: var(--font-display);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
}

.login-header__brand em {
  font-style: normal;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
}

.login-header__title {
  font-size: var(--text-5xl);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: var(--space-4);
  font-family: var(--font-display);
  letter-spacing: -0.02em;
  color: var(--text-primary);
}

.login-header__subtitle {
  font-size: var(--text-lg);
  color: var(--text-secondary);
  font-weight: 500;
  max-width: 400px;
  margin: 0 auto;
  line-height: 1.5;
}

.login-main {
  margin-bottom: var(--space-8);
}

.login-main .qr-login {
  background: var(--bg-secondary);
  border-radius: var(--radius-xl);
  padding: var(--space-8);
  border: 1px solid var(--border-default);
  transition: all var(--transition-normal);
}

.login-main .qr-login:hover {
  box-shadow: var(--shadow-md);
}

.login-main .qr-code {
  width: 180px;
  height: 180px;
  background: var(--bg-primary);
  margin: 0 auto var(--space-4);
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.login-main .qr-hint {
  font-size: var(--text-base);
  color: var(--text-secondary);
  margin-bottom: var(--space-4);
  line-height: 1.5;
}

.login-main .refresh-qr {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: none;
  border: none;
  color: var(--color-primary);
  font-size: var(--text-sm);
  cursor: pointer;
  padding: var(--space-2);
  transition: color var(--transition-fast);
}

.login-main .refresh-qr:hover {
  color: var(--color-primary-500);
}

.login-divider {
  display: flex;
  align-items: center;
  margin: var(--space-6) 0;
  gap: var(--space-4);
}

.login-divider::before,
.login-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border-default);
}

.login-divider span {
  font-size: var(--text-sm);
  color: var(--text-tertiary);
  font-weight: 500;
}

.login-icons {
  display: flex;
  justify-content: center;
  gap: var(--space-6);
}

.login-icon-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-2);
  background: var(--bg-secondary);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-xl);
  padding: var(--space-4);
  width: 80px;
  cursor: pointer;
  transition: all var(--transition-normal);
}

.login-icon-btn:hover {
  background: var(--bg-tertiary);
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-sm);
}

.login-icon-btn svg {
  width: 28px;
  height: 28px;
}

.login-icon-btn span {
  font-size: var(--text-xs);
  color: var(--text-secondary);
  font-weight: 500;
}

.form-input-with-btn {
  display: flex;
  gap: var(--space-2);
}

.form-input-with-btn .form-input {
  flex: 1;
}

.btn--send-code {
  white-space: nowrap;
  padding: 0 var(--space-4);
  color: var(--color-primary);
  font-weight: 500;
}

.btn--send-code:disabled {
  color: var(--text-tertiary);
  cursor: not-allowed;
}

.form-links {
  text-align: right;
  margin-top: calc(-1 * var(--space-2));
  margin-bottom: var(--space-4);
}

.form-links a {
  font-size: var(--text-sm);
  color: var(--color-primary);
  text-decoration: none;
}

.form-links a:hover {
  text-decoration: underline;
}

.login-actions {
  margin-bottom: var(--space-8);
}

.verification-code {
  display: flex;
  gap: var(--space-3);
}

.verification-code input {
  flex: 1;
  text-align: center;
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: 0.1em;
}

@media (max-width: 640px) {
  .login-container {
    padding: var(--space-8) var(--space-4);
  }

  .login-header__title {
    font-size: var(--text-4xl);
  }

  .login-main .qr-code {
    width: 160px;
    height: 160px;
  }

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

  .login-icon-btn {
    width: 70px;
    padding: var(--space-3);
  }

  .login-icon-btn svg {
    width: 24px;
    height: 24px;
  }
}

/* ========== 33. Toast 提示 ========== */
.toast {
  position: fixed;
  top: var(--space-4);
  right: var(--space-4);
  padding: var(--space-3) var(--space-4);
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  z-index: 2000;
  transform: translateX(120%);
  transition: transform var(--transition-normal);
}

.toast--active {
  transform: translateX(0);
}

.toast--success {
  border-color: var(--color-success);
}

.toast--error {
  border-color: var(--color-error);
}

.toast-message {
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-primary);
}

/* ========== 34. 个人中心样式 ========== */
.profile-header {
  display: flex;
  align-items: center;
  gap: var(--space-6);
  padding: var(--space-8) 0;
  margin-bottom: var(--space-8);
  border-bottom: 1px solid var(--border-default);
}

.profile-avatar {
  width: 96px;
  height: 96px;
  border-radius: var(--radius-full);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-on-primary);
  font-size: var(--text-4xl);
  font-weight: 700;
  box-shadow: var(--shadow-md);
  object-fit: cover;
}

.profile-info {
  flex: 1;
}

.profile-info__name {
  font-size: var(--text-3xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.profile-info__level {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--text-secondary);
  margin-bottom: var(--space-3);
}

.profile-info__stats {
  display: flex;
  gap: var(--space-6);
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

.profile-info__stats strong {
  font-size: var(--text-lg);
  font-weight: 700;
  color: var(--text-primary);
  display: block;
}

/* ========== 35. 词库卡片 ========== */
.word-library-card {
  background: var(--bg-elevated);
  border-radius: var(--radius-xl);
  padding: var(--space-6);
  border: 1px solid var(--border-default);
  text-align: center;
  transition: all var(--transition-normal);
  cursor: pointer;
}

.word-library-card:hover {
  border-color: var(--color-primary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-card-hover);
}

.word-library-card__icon {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-3);
}

.word-library-card__value {
  font-size: var(--text-4xl);
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: var(--space-2);
}

.word-library-card__label {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

/* ========== 36. 历史记录 ========== */
.history-list {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}

.history-item {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  padding: var(--space-4);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
}

.history-item:hover {
  background: var(--bg-tertiary);
}

.history-item__icon {
  width: 48px;
  height: 48px;
  background: var(--color-primary-50);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-2xl);
  flex-shrink: 0;
}

.history-item__content {
  flex: 1;
}

.history-item__title {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: var(--space-1);
}

.history-item__date {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

.history-item__score {
  font-size: var(--text-xl);
  font-weight: 700;
  color: var(--color-primary);
  flex-shrink: 0;
}

/* ========== 37. 账号绑定项 ========== */
.account-bind-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4);
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  margin-bottom: var(--space-3);
}

.account-bind-item__left {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.account-bind-item__icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
}

.account-bind-item__icon--phone {
  background: linear-gradient(135deg, #10B981, #059669);
}

.account-bind-item__icon--email {
  background: linear-gradient(135deg, #3B82F6, #2563EB);
}

.account-bind-item__icon--wechat {
  background: linear-gradient(135deg, #07C160, #06AD56);
}

.account-bind-item__icon--google {
  background: linear-gradient(135deg, #4285F4, #34A853, #FBBC05, #EA4335);
}

.account-bind-item__title {
  font-size: var(--text-base);
  font-weight: 500;
  color: var(--text-primary);
}

.account-bind-item__value {
  font-size: var(--text-sm);
  color: var(--text-secondary);
}

/* ========== 38. 页脚 ========== */
.footer {
  text-align: center;
  padding: var(--space-12) 0;
  color: var(--text-tertiary);
  font-size: var(--text-sm);
}

/* ========== 39. 进度指示器 ========== */
.progress-indicator {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-4) 0;
}

.progress-indicator__step {
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
  background: var(--border-default);
  flex-shrink: 0;
  transition: all var(--transition-normal);
}

.progress-indicator__step--active {
  background: var(--color-primary);
  box-shadow: 0 0 0 4px var(--color-primary-tint-15);
}

.progress-indicator__step--completed {
  background: var(--color-success);
}

/* ========== 40. 网格辅助类 ========== */
.grid--1 { grid-template-columns: 1fr; }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

@media (min-width: 640px) {
  .grid--1, .grid--2, .grid--3, .grid--4 {
    gap: var(--space-6);
  }
}

/* ========== 41. 侧边栏用户区域 ========== */
.sidebar__user {
  margin-top: auto;
  padding-top: var(--space-4);
  position: relative;
}

.sidebar__user-btn {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  width: 100%;
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-lg);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: left;
}

.sidebar__user-btn:hover {
  background: var(--bg-tertiary);
}

.sidebar__user-avatar {
  position: relative;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  flex-shrink: 0;
  overflow: hidden;
}

.sidebar__user-avatar-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: opacity 0.3s ease;
}

.sidebar__user-avatar-placeholder {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: var(--text-sm);
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-500));
  color: var(--color-on-primary);
  transition: opacity 0.3s ease;
}

.sidebar__user-name {
  flex: 1;
  font-size: var(--text-sm);
  font-weight: 600;
  color: var(--text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sidebar__user-arrow {
  width: 16px;
  height: 16px;
  color: var(--text-secondary);
  transition: transform var(--transition-fast);
  flex-shrink: 0;
}

.sidebar__user-btn.sidebar__user-btn--active .sidebar__user-arrow {
  transform: rotate(180deg);
}

.sidebar__user-menu {
  position: absolute;
  bottom: 100%;
  left: 0;
  right: 0;
  margin-bottom: var(--space-2);
  display: grid;
  gap: 0;
  padding: 18px var(--space-3);
  background: var(--bg-elevated);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: all var(--transition-normal);
  z-index: 10;
}

.sidebar__user-menu--active {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.sidebar__user-menu-item {
  display: flex;
  align-items: center;
  gap: var(--space-4);
  justify-content: flex-start;
  width: 100%;
  min-height: 52px;
  padding: 13px 18px;
  border-radius: var(--radius-lg);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-align: left;
  font-size: var(--text-sm);
  font-weight: 500;
  color: var(--text-primary);
}

.sidebar__user-menu-item:hover {
  background: var(--bg-tertiary);
  transform: none;
}

.sidebar__user-menu-item svg {
  width: 20px;
  height: 20px;
  color: var(--text-secondary);
  flex-shrink: 0;
}

.sidebar__user-menu-item--danger {
  color: var(--color-error);
  margin-top: var(--space-2);
}

.sidebar__user-menu-item--danger svg {
  color: var(--color-error);
}

.sidebar__user-menu-item--danger:hover {
  background: var(--color-error-tint);
}

/* ========== 42. 练习场景页头部搜索 ========== */
.page-header__top {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
}

@media (min-width: 768px) {
  .page-header__top {
    flex-direction: row;
    align-items: flex-end;
    justify-content: space-between;
  }
}

.page-header__search {
  width: 100%;
}

@media (min-width: 768px) {
  .page-header__search {
    max-width: 400px;
  }
}

.page-header__search-wrapper {
  position: relative;
}

.page-header__search-icon {
  position: absolute;
  left: var(--space-4);
  top: 50%;
  transform: translateY(-50%);
  width: 20px;
  height: 20px;
  color: var(--text-disabled);
}

.page-header__search-input {
  width: 100%;
  height: 48px;
  padding: 0 var(--space-4) 0 52px;
  background: var(--bg-tertiary);
  border: 1px solid transparent;
  border-radius: var(--radius-lg);
  font-size: var(--text-base);
  color: var(--text-primary);
  transition: all var(--transition-fast);
}

.page-header__search-input::placeholder {
  color: var(--text-disabled);
}

.page-header__search-input:focus {
  outline: none;
  border-color: var(--color-primary);
  background: var(--bg-primary);
}

/* ========== 43. 个人信息编辑弹窗 ========== */
.profile-edit {
  display: flex;
  flex-direction: column;
  align-items: center;
}

.profile-edit__avatar {
  position: relative;
  margin-bottom: var(--space-6);
}

.profile-edit__avatar-img {
  width: 120px;
  height: 120px;
  border-radius: var(--radius-full);
  object-fit: cover;
  border: 3px solid var(--color-primary);
}

.profile-edit__avatar-btn {
  position: absolute;
  bottom: 0;
  right: 0;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-full);
  background: var(--color-primary);
  color: var(--color-on-primary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow-sm);
}

.profile-edit__avatar-btn:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-md);
}

.profile-edit__avatar-btn svg {
  width: 18px;
  height: 18px;
}

/* ========== 44. 调整页面内容区，移除顶部栏占用的空间 ========== */
.page {
  padding-top: var(--space-6);
}

.container {
  padding-top: 0;
}