/* ============================================
   PokeDAO 商学院 · Global Styles
   深空紫 + 雷电黄 + 电子蓝 · 霸气路线
   ============================================ */

:root {
  /* 主色板 */
  --bg-void: #07030f;
  --bg-deep: #0d0820;
  --bg-card: #15102a;
  --bg-card-hover: #1c1638;
  --bg-elevated: #221a3d;

  /* 紫色谱系(主色) */
  --purple-glow: #a855f7;
  --purple-mid: #7c3aed;
  --purple-deep: #4c1d95;
  --purple-soft: #c4b5fd;

  /* 强调色 */
  --yellow-bolt: #fbbf24;
  --yellow-glow: #fde047;
  --blue-electric: #38bdf8;
  --blue-deep: #0ea5e9;
  --pink-flash: #ec4899;
  --green-cash: #10b981;
  --red-alert: #ef4444;
  --orange-fire: #fb923c;

  /* 文字 */
  --text-primary: #f5f3ff;
  --text-secondary: #c4b5fd;
  --text-muted: #8b7fb3;
  --text-dim: #5f548c;

  /* 边框 */
  --border-subtle: rgba(168, 85, 247, 0.15);
  --border-strong: rgba(168, 85, 247, 0.4);
  --border-glow: rgba(168, 85, 247, 0.6);

  /* 字体 */
  --font-display: 'Orbitron', 'Bebas Neue', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', monospace;

  /* 阴影 / 光效 */
  --glow-purple: 0 0 40px rgba(168, 85, 247, 0.4);
  --glow-yellow: 0 0 30px rgba(251, 191, 36, 0.5);
  --glow-pink: 0 0 30px rgba(236, 72, 153, 0.4);
  --shadow-card: 0 10px 40px -10px rgba(124, 58, 237, 0.3);
  --shadow-deep: 0 20px 60px -20px rgba(0, 0, 0, 0.8);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  background: var(--bg-void);
  color: var(--text-primary);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.6;
  overflow-x: hidden;
  min-height: 100vh;

  /* 背景纹理: 噪点 + 微光 */
  background-image:
    radial-gradient(ellipse at 20% 10%, rgba(124, 58, 237, 0.15), transparent 50%),
    radial-gradient(ellipse at 80% 80%, rgba(168, 85, 247, 0.1), transparent 50%),
    radial-gradient(ellipse at 50% 50%, rgba(56, 189, 248, 0.05), transparent 60%);
  background-attachment: fixed;
}

/* 全局背景颗粒纹理 */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 1;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3CfeColorMatrix values='0 0 0 0 0.4 0 0 0 0 0.2 0 0 0 0 0.6 0 0 0 0.05 0'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  opacity: 0.4;
  mix-blend-mode: overlay;
}

/* ============================================
   通用工具类
   ============================================ */
.container {
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 2;
}

.section {
  padding: 100px 0;
  position: relative;
  z-index: 2;
}

.section-label {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.3em;
  color: var(--purple-glow);
  text-transform: uppercase;
  padding: 6px 14px;
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  background: rgba(168, 85, 247, 0.08);
  margin-bottom: 24px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(32px, 5vw, 56px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #fff 0%, var(--purple-soft) 60%, var(--purple-glow) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-subtitle {
  font-size: 18px;
  color: var(--text-secondary);
  max-width: 720px;
  margin-bottom: 64px;
  line-height: 1.7;
}

/* ============================================
   导航栏
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 0;
  background: rgba(7, 3, 15, 0.7);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 24px;
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  color: var(--text-primary);
}

.nav-logo img {
  height: 36px;
  width: auto;
}

.nav-logo-text {
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.25em;
  color: var(--purple-soft);
  text-transform: uppercase;
}

.nav-menu {
  display: flex;
  gap: 36px;
  list-style: none;
}

.nav-menu a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s ease;
  position: relative;
}

.nav-menu a:hover {
  color: var(--purple-glow);
}

.nav-menu a.active {
  color: var(--yellow-bolt);
}

.nav-cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 10px 20px;
  background: linear-gradient(135deg, var(--purple-mid), var(--purple-glow));
  color: white;
  text-decoration: none;
  font-size: 14px;
  font-weight: 600;
  border-radius: 6px;
  transition: all 0.2s ease;
  box-shadow: 0 4px 20px -4px rgba(168, 85, 247, 0.6);
}

.nav-cta:hover {
  transform: translateY(-1px);
  box-shadow: 0 8px 30px -4px rgba(168, 85, 247, 0.8);
}

/* 移动端菜单 */
.nav-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 8px;
}

@media (max-width: 768px) {
  .nav-menu {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-deep);
    flex-direction: column;
    padding: 20px 24px;
    gap: 20px;
    border-bottom: 1px solid var(--border-subtle);
  }
  .nav-menu.open { display: flex; }
  .nav-toggle { display: block; }
  .nav-cta { padding: 8px 14px; font-size: 12px; }
}

/* ============================================
   按钮通用
   ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 28px;
  font-family: var(--font-body);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 8px;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, var(--purple-mid), var(--purple-glow));
  color: white;
  box-shadow: 0 6px 24px -6px rgba(168, 85, 247, 0.7);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 36px -6px rgba(168, 85, 247, 0.9);
}

.btn-secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-strong);
}

.btn-secondary:hover {
  background: rgba(168, 85, 247, 0.1);
  border-color: var(--purple-glow);
}

.btn-yellow {
  background: linear-gradient(135deg, var(--yellow-bolt), var(--orange-fire));
  color: #1a0f00;
  box-shadow: 0 6px 24px -6px rgba(251, 191, 36, 0.7);
}

.btn-yellow:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 36px -6px rgba(251, 191, 36, 0.9);
}

/* ============================================
   Footer (共用)
   ============================================ */
.footer {
  background: linear-gradient(180deg, transparent, rgba(0, 0, 0, 0.6));
  padding: 80px 0 40px;
  border-top: 1px solid var(--border-subtle);
  margin-top: 80px;
  position: relative;
  z-index: 2;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 48px;
  margin-bottom: 48px;
}

@media (max-width: 768px) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 32px;
  }
}

.footer-brand img {
  height: 44px;
  margin-bottom: 16px;
}

.footer-tagline {
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.7;
  max-width: 320px;
}

.footer-col h4 {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--purple-glow);
  text-transform: uppercase;
  margin-bottom: 20px;
}

.footer-col ul {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-col a {
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s ease;
}

.footer-col a:hover {
  color: var(--yellow-bolt);
}

.footer-bottom {
  padding-top: 32px;
  border-top: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 13px;
  color: var(--text-muted);
}

.footer-slogan {
  font-family: var(--font-display);
  letter-spacing: 0.15em;
  color: var(--purple-soft);
  font-size: 12px;
}

/* ============================================
   动画
   ============================================ */
@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px rgba(168, 85, 247, 0.4); }
  50% { box-shadow: 0 0 40px rgba(168, 85, 247, 0.8); }
}

@keyframes float-up {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

@keyframes spin-slow {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.fade-in {
  animation: float-up 0.8s ease forwards;
  opacity: 0;
}

.delay-1 { animation-delay: 0.15s; }
.delay-2 { animation-delay: 0.3s; }
.delay-3 { animation-delay: 0.45s; }
.delay-4 { animation-delay: 0.6s; }
.delay-5 { animation-delay: 0.75s; }

/* ============================================
   入场动画(可选增强,默认元素是显示的)
   只有加上 .reveal-init 才会先隐藏 → 等 .reveal-in 触发淡入
   兜底:JS 1.2s 后强制全部 .reveal-in,绝不留空白
   ============================================ */
.reveal-init {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal-init.reveal-in {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   v2 共用扩展样式
   ============================================ */

/* 用户徽章(导航右上角等级显示) */
.user-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: rgba(168, 85, 247, 0.1);
  border: 1px solid var(--border-strong);
  border-radius: 100px;
  font-size: 12px;
  color: var(--text-primary);
}

.user-badge-tier {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 11px;
  padding: 2px 8px;
  border-radius: 4px;
  letter-spacing: 0.05em;
}

.user-badge-tier.mst { background: rgba(168, 85, 247, 0.2); color: var(--purple-glow); }
.user-badge-tier.scl { background: rgba(56, 189, 248, 0.2); color: var(--blue-electric); }
.user-badge-tier.tts { background: rgba(236, 72, 153, 0.2); color: var(--pink-flash); }
.user-badge-tier.tsm { background: rgba(251, 191, 36, 0.2); color: var(--yellow-bolt); }

/* 表单样式 */
.form-group { margin-bottom: 20px; }
.form-label {
  display: block;
  font-size: 12px;
  font-weight: 700;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: 0.05em;
}
.form-label .required { color: var(--red-alert); margin-left: 4px; }
.form-label .optional { color: var(--text-muted); font-weight: 400; margin-left: 6px; font-size: 11px; }
.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: 14px 16px;
  background: var(--bg-deep);
  border: 1px solid var(--border-subtle);
  border-radius: 10px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 14px;
  outline: none;
  transition: border-color 0.2s ease;
}
.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  border-color: var(--purple-glow);
  background: var(--bg-card);
}
.form-input::placeholder { color: var(--text-dim); }
.form-textarea { min-height: 100px; resize: vertical; }
.form-hint {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 6px;
  line-height: 1.5;
}
.form-hint.warning { color: var(--orange-fire); }

/* 步骤标题 */
.form-step {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px dashed var(--border-subtle);
}
.form-step:last-of-type { border-bottom: none; }
.form-step-title {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.15em;
  color: var(--purple-glow);
  margin-bottom: 16px;
  text-transform: uppercase;
}
.form-step-num {
  width: 28px;
  height: 28px;
  background: var(--purple-mid);
  color: white;
  border-radius: 50%;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-size: 13px;
  font-weight: 900;
}

/* Page container 居中卡片(注册/登录用) */
.page-card {
  max-width: 560px;
  margin: 100px auto 40px;
  padding: 48px;
  background: var(--bg-card);
  border: 1px solid var(--border-strong);
  border-radius: 20px;
  box-shadow: var(--shadow-deep);
  position: relative;
  z-index: 2;
}

.page-card.wide { max-width: 720px; }

.page-card-title {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.page-card-subtitle {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 36px;
}

/* 状态徽章 */
.status-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 100px;
  font-family: var(--font-display);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}
.status-badge.pending { background: rgba(251, 146, 60, 0.15); color: var(--orange-fire); }
.status-badge.approved { background: rgba(16, 185, 129, 0.15); color: var(--green-cash); }
.status-badge.rejected { background: rgba(239, 68, 68, 0.15); color: var(--red-alert); }
.status-badge.locked { background: rgba(95, 84, 140, 0.15); color: var(--text-muted); }

/* ============================================
   Dashboard 布局
   ============================================ */
.dash-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  min-height: 100vh;
  position: relative;
  z-index: 2;
}

@media (max-width: 768px) {
  .dash-layout { grid-template-columns: 1fr; }
}

.dash-sidebar {
  background: var(--bg-deep);
  border-right: 1px solid var(--border-subtle);
  padding: 24px 0;
  position: sticky;
  top: 0;
  height: 100vh;
  overflow-y: auto;
}

@media (max-width: 768px) {
  .dash-sidebar {
    position: relative;
    height: auto;
    padding: 12px 0;
    border-right: none;
    border-bottom: 1px solid var(--border-subtle);
  }
}

.dash-brand {
  padding: 0 24px 24px;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 16px;
}

.dash-brand img {
  height: 32px;
  margin-bottom: 6px;
}

.dash-brand-text {
  font-family: var(--font-display);
  font-size: 10px;
  letter-spacing: 0.25em;
  color: var(--purple-soft);
  text-transform: uppercase;
}

.dash-nav-section {
  padding: 12px 0;
}

.dash-nav-label {
  padding: 0 24px 8px;
  font-family: var(--font-display);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.25em;
  color: var(--text-muted);
  text-transform: uppercase;
}

.dash-nav-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 24px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: all 0.2s ease;
  position: relative;
  cursor: pointer;
  border: none;
  background: none;
  width: 100%;
  text-align: left;
  font-family: var(--font-body);
}

.dash-nav-item:hover {
  background: rgba(168, 85, 247, 0.08);
  color: var(--text-primary);
}

.dash-nav-item.active {
  background: linear-gradient(90deg, rgba(168, 85, 247, 0.15), transparent);
  color: var(--text-primary);
  border-left: 3px solid var(--purple-glow);
  padding-left: 21px;
}

.dash-nav-icon {
  font-size: 18px;
  width: 24px;
  text-align: center;
}

.dash-nav-item.locked {
  color: var(--text-dim);
  cursor: not-allowed;
}

.dash-nav-item.locked:hover {
  background: rgba(239, 68, 68, 0.05);
  color: var(--text-muted);
}

.dash-nav-lock {
  margin-left: auto;
  font-size: 14px;
  opacity: 0.6;
}

.dash-nav-divider {
  height: 1px;
  background: var(--border-subtle);
  margin: 8px 24px;
}

.dash-nav-user {
  margin-top: auto;
  padding: 16px 24px;
  border-top: 1px solid var(--border-subtle);
}

.dash-user-info {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.dash-user-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--purple-mid), var(--purple-glow));
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 14px;
}

.dash-user-meta {
  flex: 1;
  min-width: 0;
}

.dash-user-name {
  font-size: 13px;
  font-weight: 700;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.dash-user-wallet {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--text-muted);
}

.dash-logout {
  display: block;
  width: 100%;
  padding: 8px 12px;
  background: transparent;
  border: 1px solid var(--border-subtle);
  border-radius: 6px;
  color: var(--text-secondary);
  font-size: 12px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.dash-logout:hover {
  border-color: var(--red-alert);
  color: var(--red-alert);
}

.dash-main {
  padding: 32px 40px;
  min-height: 100vh;
  overflow-x: hidden;
}

@media (max-width: 768px) {
  .dash-main { padding: 24px 16px; }
}

.dash-section { display: none; }
.dash-section.active { display: block; animation: fade-in 0.3s ease; }

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

.dash-section-header {
  margin-bottom: 32px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--border-subtle);
}

.dash-section-title {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 900;
  color: var(--text-primary);
  margin-bottom: 8px;
  letter-spacing: -0.01em;
}

.dash-section-subtitle {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.6;
}

.dash-iframe-container {
  width: 100%;
  height: calc(100vh - 80px);
  background: var(--bg-deep);
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border-subtle);
}

.dash-iframe-container iframe {
  width: 100%;
  height: 100%;
  border: none;
  display: block;
}

/* Stat 卡片 */
.stat-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 32px;
}

.stat-card {
  padding: 20px 24px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
  position: relative;
  overflow: hidden;
}

.stat-card-label {
  font-family: var(--font-display);
  font-size: 10px;
  letter-spacing: 0.2em;
  color: var(--text-muted);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.stat-card-value {
  font-family: var(--font-display);
  font-size: 28px;
  font-weight: 900;
  color: var(--text-primary);
  line-height: 1;
  margin-bottom: 4px;
}

.stat-card-value.gold { color: var(--yellow-bolt); }
.stat-card-value.green { color: var(--green-cash); }
.stat-card-value.purple { color: var(--purple-glow); }

.stat-card-meta {
  font-size: 11px;
  color: var(--text-muted);
}

/* Lock card 锁定课程预览卡 */
.lock-card {
  position: relative;
  padding: 32px;
  background: linear-gradient(135deg, var(--bg-card), var(--bg-deep));
  border: 1px solid var(--border-subtle);
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 16px;
}

.lock-card::before {
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    135deg,
    transparent 0,
    transparent 20px,
    rgba(95, 84, 140, 0.05) 20px,
    rgba(95, 84, 140, 0.05) 22px
  );
  pointer-events: none;
}

.lock-card-content {
  position: relative;
  z-index: 1;
}

.lock-card-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 16px;
}

.lock-card-title {
  font-family: var(--font-display);
  font-size: 24px;
  font-weight: 900;
  color: var(--text-secondary);
  margin-bottom: 4px;
}

.lock-card-sub {
  font-size: 13px;
  color: var(--text-muted);
}

.lock-icon-large {
  font-size: 32px;
  opacity: 0.6;
}

.lock-card-desc {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.lock-card-requirements {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 20px;
  background: rgba(7, 3, 15, 0.5);
  border-radius: 8px;
  margin-bottom: 20px;
}

.lock-req-item {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  color: var(--text-secondary);
}

.lock-req-icon {
  font-size: 14px;
  flex-shrink: 0;
}

.lock-req-icon.done { color: var(--green-cash); }
.lock-req-icon.pending { color: var(--text-muted); }

.lock-req-item.done { color: var(--text-primary); }
.lock-req-item.done .lock-req-text { text-decoration: line-through; opacity: 0.7; }


/* ============================================
   语言切换按钮(右上角)
   ============================================ */
.lang-switch {
  display: inline-flex;
  align-items: center;
  background: rgba(7, 3, 15, 0.6);
  border: 1px solid var(--border-subtle);
  border-radius: 100px;
  padding: 3px;
  gap: 2px;
}

.lang-btn {
  background: transparent;
  border: none;
  padding: 5px 12px;
  border-radius: 100px;
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 700;
  font-family: var(--font-display);
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: all 0.2s ease;
  min-width: 32px;
}

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

.lang-btn.active {
  background: var(--purple-glow);
  color: white;
}

/* 移动端紧凑 */
@media (max-width: 768px) {
  .lang-btn {
    padding: 4px 10px;
    font-size: 11px;
  }
}