:root {
  /* 颜色变量定义 - 与 Tailwind 配置对应 */
  --color-paper: #EBEEFA;
  --color-card: #FFFFFF;
  --color-ink: #1F1633;
  --color-muted: #5B647A;
  --color-subtle: #7B8398;
  --color-stroke: #DDE3F4;
  --color-primary: #C7B3FF;
  --color-primaryDeep: #9F86FF;
  
  /* 新增的 Tailwind 兼容颜色变量 */
  --tw-color-paper: var(--color-paper);
  --tw-color-card: var(--color-card);
  --tw-color-ink: var(--color-ink);
  --tw-color-muted: var(--color-muted);
  --tw-color-subtle: var(--color-subtle);
  --tw-color-stroke: var(--color-stroke);
  --tw-color-primary: var(--color-primary);
  --tw-color-primaryDeep: var(--color-primaryDeep);
  
  /* 辅助颜色变量 */
  --color-primary-light: rgba(199, 179, 255, 0.55);
  --color-primaryDeep-light: rgba(159, 134, 255, 0.55);
  --color-accent: #A79FBF;
  --color-dark-bg: #07060A;
  --color-dark-card: rgba(255, 255, 255, 0.05);
  --color-dark-stroke: rgba(255, 255, 255, 0.12);
  --color-gold: #EBCB7A;
  --color-light-bg: rgba(247, 244, 255, 0.78);
  --color-white-transparent-90: rgba(255, 255, 255, 0.9);
  --color-white-transparent-80: rgba(255, 255, 255, 0.8);
  --color-white-transparent-70: rgba(255, 255, 255, 0.7);
  --color-white-transparent-50: rgba(255, 255, 255, 0.5);
  --color-white-transparent-30: rgba(255, 255, 255, 0.3);
  --color-white-transparent-20: rgba(255, 255, 255, 0.2);
  --color-white-transparent-10: rgba(255, 255, 255, 0.1);
  --color-black-transparent-70: rgba(7, 6, 10, 0.7);
  --color-black-transparent-30: rgba(0, 0, 0, 0.3);
  --color-black-transparent-10: rgba(31, 22, 51, 0.1);

  --color-bg-dropdown-menu: var(--color-card, #FFFFFF);
  --color-dark-bg-dropdown-menu: #1a112e;
}

/* 确保 Tailwind 使用我们的变量 */
.text-ink { color: var(--tw-color-ink); }
.text-muted { color: var(--tw-color-muted); }
.text-subtle { color: var(--tw-color-subtle); }
.text-primary { color: var(--tw-color-primary); }
.text-primaryDeep { color: var(--tw-color-primaryDeep); }
.bg-paper { background-color: var(--tw-color-paper); }
.bg-card { background-color: var(--tw-color-card); }
.bg-primary { background-color: var(--tw-color-primary); }
.bg-primaryDeep { background-color: var(--tw-color-primaryDeep); }
.border-stroke { border-color: var(--tw-color-stroke); }

/* 深色模式下的 Tailwind 颜色覆盖 */
.dark .text-ink { color: rgba(247, 244, 255, 0.78); }
.dark .text-muted { color: #CFC8E6; }
.dark .text-subtle { color: var(--color-accent); }
.dark .text-primaryDeep { color: var(--color-gold); }
.dark .bg-primaryDeep { background-color: #78E6FF; }
.dark .border-stroke { border-color: rgba(255, 255, 255, 0.14); }

/* 其余的 CSS 保持不变... */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--color-paper);
}

::-webkit-scrollbar-thumb {
  background: rgba(159, 134, 255, 0.38);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-primaryDeep-light);
}

html {
  scroll-behavior: smooth;
}

::selection {
  background: var(--color-primary-light);
  color: var(--color-ink);
}

/* 页面背景 */
.page-bg {
  background:
    radial-gradient(900px 280px at 18% 0%, rgba(255, 255, 255, 0.98), transparent 62%),
    radial-gradient(860px 260px at 78% -20%, rgba(255, 255, 255, 0.96), transparent 60%),
    radial-gradient(760px 240px at 55% 6%, rgba(255, 255, 255, 0.92), transparent 64%),
    radial-gradient(820px 420px at 22% 22%, rgba(199, 179, 255, 0.3), transparent 62%),
    radial-gradient(740px 400px at 82% 32%, rgba(159, 134, 255, 0.18), transparent 64%),
    linear-gradient(180deg, var(--color-paper) 0%, var(--color-card) 62%, var(--color-card) 100%);
}

/* UI 卡片 */
.ui-card {
  background: var(--color-card);
  border: 1px solid var(--color-stroke);
  box-shadow: 0 28px 60px rgba(159, 134, 255, 0.16), 0 14px 30px rgba(31, 22, 51, 0.06);
  transition: box-shadow 160ms ease, transform 160ms ease, border-color 160ms ease;
}

.ui-card:hover {
  border-color: var(--color-primary-light);
  box-shadow: 0 34px 74px rgba(159, 134, 255, 0.2), 0 16px 34px rgba(31, 22, 51, 0.07);
  transform: translateY(-1px);
}

/* UI 标签 */
.ui-pill {
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--color-stroke);
}

/* UI 按钮 */
.ui-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 12px 18px;
  border-radius: 9999px;
  font-weight: 650;
  letter-spacing: 0.2px;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease, border-color 160ms ease, color 160ms ease;
  will-change: transform;
}

.ui-btn:active {
  transform: translateY(1px);
}

/* 主按钮 */
.ui-btn-primary {
  color: var(--color-ink);
  background: var(--color-primary);
  box-shadow: 0 18px 34px rgba(159, 134, 255, 0.22), 0 10px 22px rgba(31, 22, 51, 0.1);
}

.ui-btn-primary:hover {
  background: #B9A2FF;
  box-shadow: 0 20px 40px rgba(159, 134, 255, 0.26), 0 12px 26px rgba(31, 22, 51, 0.12);
  transform: translateY(-1px);
}

/* 次按钮 */
.ui-btn-secondary {
  color: var(--color-ink);
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid var(--color-stroke);
}

.ui-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.92);
  border-color: var(--color-primary-light);
  transform: translateY(-1px);
}

/* 链接 */
.ui-link {
  color: rgba(91, 100, 122, 0.95);
  transition: color 160ms ease;
}

.ui-link:hover {
  color: var(--color-ink);
}

/* Hero 背景 */
.hero-bg {
  background:
    radial-gradient(980px 300px at 20% 0%, rgba(255, 255, 255, 0.98), transparent 62%),
    radial-gradient(920px 280px at 72% -10%, rgba(255, 255, 255, 0.96), transparent 60%),
    radial-gradient(820px 420px at 25% 30%, rgba(199, 179, 255, 0.26), transparent 66%),
    radial-gradient(760px 420px at 78% 42%, rgba(159, 134, 255, 0.16), transparent 66%);
}

/* ========== 深色主题样式 ========== */
.dark ::-webkit-scrollbar-track {
  background: var(--color-dark-bg);
}

.dark ::-webkit-scrollbar-thumb {
  background: rgba(184, 161, 255, 0.28);
}

.dark ::-webkit-scrollbar-thumb:hover {
  background: rgba(235, 203, 122, 0.55);
}

.dark ::selection {
  background: rgba(184, 161, 255, 0.45);
  color: var(--color-dark-bg);
}

.dark .page-bg {
  background:
    radial-gradient(700px 380px at 15% 25%, rgba(184, 161, 255, 0.22), transparent 60%),
    radial-gradient(560px 320px at 70% 35%, rgba(120, 230, 255, 0.14), transparent 60%),
    radial-gradient(520px 360px at 85% 70%, rgba(235, 203, 122, 0.12), transparent 60%),
    var(--color-dark-bg);
}

.dark .hero-bg {
  background:
    radial-gradient(700px 380px at 15% 25%, rgba(184, 161, 255, 0.22), transparent 60%),
    radial-gradient(560px 320px at 70% 35%, rgba(120, 230, 255, 0.14), transparent 60%),
    radial-gradient(520px 360px at 85% 70%, rgba(235, 203, 122, 0.12), transparent 60%);
}

.dark .ui-card {
  background: rgba(255, 255, 255, 0.06);
  backdrop-filter: blur(14px);
  border: 1px solid rgba(255, 255, 255, 0.14);
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.45);
}

.dark .ui-card:hover {
  border-color: rgba(235, 203, 122, 0.3);
  background: rgba(255, 255, 255, 0.08);
  transform: translateY(-1px);
}

.dark .ui-pill {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.dark .ui-btn-primary {
  color: var(--color-dark-bg);
  background: linear-gradient(135deg, #B8A1FF 0%, #EBCB7A 55%, #78E6FF 140%);
  box-shadow: 0 12px 30px rgba(184, 161, 255, 0.22), 0 10px 22px rgba(235, 203, 122, 0.16);
}

.dark .ui-btn-primary:hover {
  box-shadow: 0 14px 36px rgba(184, 161, 255, 0.26), 0 12px 26px rgba(235, 203, 122, 0.22);
  transform: translateY(-1px);
}

.dark .ui-btn-secondary {
  color: rgba(247, 244, 255, 0.78);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.16);
}

.dark .ui-btn-secondary:hover {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.22);
  transform: translateY(-1px);
}

.dark .ui-link {
  color: rgba(247, 244, 255, 0.78);
}

.dark .ui-link:hover {
  color: rgba(247, 244, 255, 0.78);
}

.dark nav {
  background: rgba(7, 6, 10, 0.7);
  border-bottom-color: rgba(255, 255, 255, 0.1);
}

.dark footer {
  background: var(--color-dark-bg);
  border-top-color: rgba(255, 255, 255, 0.1);
}

/* 简体/繁体下拉菜单样式 - 最小化改动 */
[data-lang-select] {
  border-radius: 1rem !important;
  background: var(--color-bg-dropdown-menu) !important;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1) !important;
  border: 1px solid var(--color-stroke, #DDE3F4) !important;
}

/* 深色模式下的简体/繁体下拉菜单 */
.dark [data-lang-select] {
  background: var(--color-dark-bg-dropdown-menu) !important;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3) !important;
  border: 1px solid rgba(255, 255, 255, 0.14) !important;
}

/* 下拉菜单基础样式 */
.dropdown-menu {
  z-index: 1000;
  background: var(--color-bg-dropdown-menu);  
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
  border: 1px solid var(--color-stroke, #DDE3F4);
  position: absolute;
  /* 默认向下展开 */
  top: 100%;
  left: 0;
  margin-top: 0.5rem;
}

/* 向上展开的菜单 */
.dropdown-menu-up {
  top: auto;
  bottom: 100%;
  margin-top: 0;
  margin-bottom: 0.5rem;
}

/* 深色模式下的下拉菜单 */
.dark .dropdown-menu {
  background: var(--color-dark-bg-dropdown-menu);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  border: 1px solid rgba(255, 255, 255, 0.14);
}

/* 确保下拉菜单在小屏幕上也能正常显示 */
@media (max-width: 640px) {
  .dropdown-menu {
    width: 100%;
    left: 0;
    right: 0;
  }
}