/* ========== Reset & Base ========== */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg-dark: #0d1117;
  --bg-mid: #161b22;
  --bg-card: #1c2330;
  --gold: #c9a86a;
  --gold-light: #e0c488;
  --text: #e0d6c8;
  --text-dim: #9b9080;
  --text-second: #b8a88a;
  --accent: #6a8caf;
  --border: #2a3340;
  --radius: 10px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", -apple-system, sans-serif;
  background: var(--bg-dark);
  color: var(--text);
  line-height: 1.7;
  overflow-x: hidden;
}

.container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ========== 语言切换 ========== */
.lang-switcher {
  position: fixed;
  top: 20px;
  right: 24px;
  z-index: 1000;
}

.lang-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  background: rgba(13, 17, 23, 0.85);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--gold-light);
  font-size: 14px;
  cursor: pointer;
  transition: all 0.3s;
  backdrop-filter: blur(8px);
}

.lang-btn:hover {
  border-color: var(--gold);
  background: rgba(201, 168, 106, 0.1);
}

.lang-menu {
  list-style: none;
  position: absolute;
  top: 100%;
  right: 0;
  margin-top: 6px;
  background: rgba(13, 17, 23, 0.95);
  border: 1px solid var(--border);
  border-radius: 8px;
  overflow: hidden;
  display: none;
  backdrop-filter: blur(12px);
  min-width: 130px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

.lang-menu.open {
  display: block;
}

.lang-menu li {
  padding: 10px 18px;
  font-size: 14px;
  color: var(--text-dim);
  cursor: pointer;
  transition: all 0.2s;
}

.lang-menu li:hover {
  background: rgba(201, 168, 106, 0.12);
  color: var(--gold-light);
}

/* ========== Hero ========== */
.hero {
  height: 100vh;
  min-height: 560px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  background: linear-gradient(135deg, #0d1117 0%, #1a1f2e 30%, #15202b 60%, #0d1117 100%);
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 30% 40%, rgba(201, 168, 106, 0.08) 0%, transparent 50%),
    radial-gradient(ellipse at 70% 60%, rgba(106, 140, 175, 0.06) 0%, transparent 50%);
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(90deg, transparent 0, transparent 2px, rgba(201,168,106,0.015) 2px, rgba(201,168,106,0.015) 4px);
  pointer-events: none;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, transparent 0%, transparent 60%, rgba(13, 17, 23, 0.8) 100%);
}

.hero-content {
  text-align: center;
  position: relative;
  z-index: 2;
  padding: 0 24px;
}

.hero-title {
  font-size: clamp(2rem, 6vw, 4.5rem);
  font-weight: 300;
  letter-spacing: 0.15em;
  color: var(--gold-light);
  text-shadow: 0 0 60px rgba(201, 168, 106, 0.3);
  margin-bottom: 20px;
}

.hero-sub {
  font-size: clamp(0.85rem, 1.5vw, 1.1rem);
  color: var(--text-dim);
  letter-spacing: 0.1em;
  max-width: 600px;
  margin: 0 auto;
  min-height: 1.5em;
}

/* ========== Section Common ========== */
.section-title {
  text-align: center;
  margin-bottom: 12px;
}

.section-title .zh,
.section-desc .zh,
.info-card h3 .zh,
.info-card p .zh,
.hero-sub .zh {
  display: block;
}

.section-title .zh {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 400;
  color: var(--gold);
  letter-spacing: 0.08em;
}

.section-title .second-lang {
  display: block;
  font-size: clamp(0.9rem, 1.8vw, 1.2rem);
  color: var(--text-second);
  font-weight: 300;
  margin-top: 4px;
  min-height: 1.2em;
}

.section-desc {
  text-align: center;
  margin-bottom: 48px;
}

.section-desc .zh {
  font-size: 1rem;
  color: var(--text-dim);
}

.section-desc .second-lang {
  display: block;
  font-size: 0.85rem;
  color: var(--text-second);
  margin-top: 2px;
  min-height: 1.2em;
}

/* hero sub 双语言 */
.hero-sub .zh {
  font-size: clamp(0.8rem, 1.3vw, 1.05rem);
  color: var(--text-dim);
  letter-spacing: 0.06em;
  margin-bottom: 10px;
  line-height: 2;
  max-width: 750px;
  margin-left: auto;
  margin-right: auto;
}

.hero-sub .second-lang {
  display: block;
  font-size: clamp(0.75rem, 1.15vw, 0.92rem);
  color: var(--text-second);
  letter-spacing: 0.03em;
  line-height: 1.85;
  max-width: 750px;
  margin: 0 auto;
  min-height: 1.2em;
}

/* info card 双语言 */
.info-card h3 .zh {
  display: block;
  font-size: 1.15rem;
  color: var(--gold-light);
  font-weight: 500;
  margin-bottom: 2px;
}

.info-card h3 .second-lang {
  display: block;
  font-size: 0.95rem;
  color: var(--text-second);
  font-weight: 400;
  min-height: 1.2em;
}

.info-card p .zh {
  display: block;
  font-size: 0.9rem;
  color: var(--text);
  line-height: 1.8;
  margin-bottom: 6px;
}

.info-card p .second-lang {
  display: block;
  font-size: 0.82rem;
  color: var(--text-second);
  line-height: 1.7;
  min-height: 1.2em;
}

/* ========== Download Section ========== */
.download-section {
  padding: 100px 0;
  background: var(--bg-dark);
}

.download-section::before {
  display: none;
}

.download-cards {
  display: flex;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
}

.dl-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 32px;
  width: 240px;
  text-align: center;
  transition: all 0.4s;
}

.dl-card:hover {
  border-color: var(--gold);
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(201, 168, 106, 0.1);
}

.dl-icon {
  margin-bottom: 20px;
}

.dl-name {
  margin-bottom: 24px;
}

.dl-name .dl-zh {
  display: block;
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--text);
  margin-bottom: 4px;
}

.dl-name .dl-en {
  display: block;
  font-size: 0.9rem;
  color: var(--text-second);
  min-height: 1.2em;
}

.dl-links {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.dl-btn {
  display: block;
  padding: 10px 20px;
  border-radius: 6px;
  font-size: 0.9rem;
  text-decoration: none;
  transition: all 0.3s;
  letter-spacing: 0.05em;
}

.dl-btn-cn {
  background: var(--gold);
  color: #0d1117;
  font-weight: 500;
}

.dl-btn-cn:hover {
  background: var(--gold-light);
}

.dl-btn-en {
  background: rgba(201, 168, 106, 0.15);
  border: 1px solid var(--gold);
  color: var(--gold-light);
  font-weight: 500;
}

.dl-btn-en:hover {
  background: rgba(201, 168, 106, 0.25);
  border-color: var(--gold-light);
}

/* ========== Info Section ========== */
.info-section {
  padding: 100px 0;
  background: var(--bg-dark);
}

.info-cards {
  display: flex;
  justify-content: center;
  gap: 20px;
  flex-wrap: wrap;
}

.info-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 30px 20px;
  flex: 1 1 180px;
  max-width: 220px;
  transition: all 0.4s;
}

.info-card:hover {
  border-color: var(--accent);
  transform: translateY(-2px);
}

.info-icon {
  font-size: 2.5rem;
  color: var(--gold);
  margin-bottom: 16px;
}

.info-card h3 {
  font-size: 1.15rem;
  color: var(--gold-light);
  margin-bottom: 12px;
  font-weight: 500;
}

.info-card p {
  font-size: 0.9rem;
  color: var(--text-dim);
  line-height: 1.8;
}

/* ========== Footer ========== */
.footer {
  background: var(--bg-dark);
  padding: 48px 0;
  text-align: center;
  border-top: 1px solid var(--border);
}

.footer-content > p {
  margin-bottom: 8px;
  font-size: 0.85rem;
}

.footer-brand {
  color: var(--gold) !important;
  font-size: 1rem !important;
  margin-bottom: 16px !important;
  letter-spacing: 0.1em;
}

.footer-icp a,
.footer-email a {
  color: var(--text-dim);
  text-decoration: none;
  transition: color 0.3s;
}

.footer-icp a:hover,
.footer-email a:hover {
  color: var(--gold-light);
}

.footer-copy {
  color: var(--text-dim) !important;
  opacity: 0.6;
  margin-top: 16px !important;
}

/* ========== Responsive ========== */
@media (max-width: 768px) {
  .download-cards {
    gap: 20px;
  }

  .dl-card {
    width: 100%;
    max-width: 320px;
  }

  .info-cards {
    gap: 20px;
    flex-wrap: wrap;
  }

  .info-card {
    max-width: 360px;
  }

  .lang-switcher {
    top: 14px;
    right: 14px;
  }
}