:root {
  --bg: #0a0a0f;
  --bg-soft: #12121a;
  --fg: #ededf2;
  --fg-soft: #a0a0b0;
  --fg-mute: #6b6b78;
  --accent: #ff6b35;
  --accent-2: #ffb86b;
  --line: rgba(255, 255, 255, 0.08);
  --card: rgba(255, 255, 255, 0.03);
  --card-hover: rgba(255, 255, 255, 0.06);
  --radius: 16px;
  --maxw: 1100px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--fg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
  position: relative;
}

/* Background layers */
.bg-gradient {
  position: fixed;
  inset: 0;
  background: radial-gradient(
      ellipse 80% 50% at 50% -20%,
      rgba(255, 107, 53, 0.18),
      transparent 60%
    ),
    radial-gradient(ellipse 60% 50% at 80% 30%, rgba(120, 80, 255, 0.12), transparent 60%),
    radial-gradient(ellipse 60% 50% at 20% 60%, rgba(50, 180, 255, 0.08), transparent 60%);
  z-index: -2;
  pointer-events: none;
}

.bg-grid {
  position: fixed;
  inset: 0;
  background-image: linear-gradient(rgba(255, 255, 255, 0.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.025) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, #000, transparent 80%);
  -webkit-mask-image: radial-gradient(ellipse 70% 60% at 50% 30%, #000, transparent 80%);
  z-index: -1;
  pointer-events: none;
}

/* Nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  background: rgba(10, 10, 15, 0.6);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-size: 20px;
  font-weight: 800;
  text-decoration: none;
  color: var(--fg);
  letter-spacing: -0.02em;
}

.logo-x {
  color: var(--accent);
  margin-right: 2px;
}

.logo-rest {
  color: var(--fg);
}

.nav-links {
  display: flex;
  gap: 28px;
}

.nav-links a {
  color: var(--fg-soft);
  text-decoration: none;
  font-size: 14px;
  transition: color 0.2s;
}

.nav-links a:hover {
  color: var(--fg);
}

/* Hero */
.hero {
  padding: 120px 24px 80px;
  text-align: center;
}

.hero-inner {
  max-width: 820px;
  margin: 0 auto;
}

.badge {
  display: inline-block;
  padding: 6px 14px;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 13px;
  color: var(--fg-soft);
  letter-spacing: 0.05em;
  margin-bottom: 28px;
  background: rgba(255, 255, 255, 0.02);
}

.hero-title {
  font-size: clamp(40px, 7vw, 72px);
  font-weight: 800;
  line-height: 1.1;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
  background: linear-gradient(180deg, #ffffff 0%, #b8b8c8 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.hero-sub {
  font-size: clamp(15px, 2vw, 18px);
  color: var(--fg-soft);
  max-width: 580px;
  margin: 0 auto 40px;
  line-height: 1.7;
}

.hero-cta {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

.btn {
  display: inline-block;
  padding: 14px 28px;
  border-radius: 12px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: all 0.2s;
  border: 1px solid transparent;
  cursor: pointer;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  color: #0a0a0f;
  box-shadow: 0 8px 30px rgba(255, 107, 53, 0.3);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 12px 40px rgba(255, 107, 53, 0.4);
}

.btn-ghost {
  color: var(--fg);
  border-color: var(--line);
  background: rgba(255, 255, 255, 0.02);
}

.btn-ghost:hover {
  background: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.15);
}

/* Sections */
.section {
  padding: 100px 24px;
}

.section-alt {
  background: linear-gradient(
    180deg,
    transparent 0%,
    rgba(255, 255, 255, 0.015) 50%,
    transparent 100%
  );
}

.section-inner {
  max-width: var(--maxw);
  margin: 0 auto;
}

.section-head {
  text-align: center;
  margin-bottom: 64px;
}

.kicker {
  display: inline-block;
  font-size: 13px;
  color: var(--accent);
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.section-head h2 {
  font-size: clamp(28px, 4.5vw, 44px);
  font-weight: 800;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.section-desc {
  margin-top: 16px;
  color: var(--fg-soft);
  font-size: 16px;
}

.lead {
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
  color: var(--fg-soft);
  font-size: 17px;
  line-height: 1.8;
}

/* Cards */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px 28px;
  transition: all 0.25s ease;
}

.card:hover {
  background: var(--card-hover);
  border-color: rgba(255, 255, 255, 0.15);
  transform: translateY(-4px);
}

.card-num {
  font-family: "SF Mono", ui-monospace, Menlo, Consolas, monospace;
  font-size: 28px;
  font-weight: 700;
  color: var(--fg-mute);
  letter-spacing: 0.02em;
  margin-bottom: 28px;
  font-variant-numeric: tabular-nums;
  line-height: 1;
}

.card:hover .card-num {
  color: var(--accent);
  transition: color 0.2s ease;
}

.card h3 {
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 10px;
  letter-spacing: -0.01em;
}

.card p {
  color: var(--fg-soft);
  font-size: 15px;
  line-height: 1.7;
}

/* QR Section */
.section-join {
  padding-bottom: 140px;
}

.qr-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.qr-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 32px 24px;
  text-align: center;
  position: relative;
  transition: all 0.25s ease;
}

.qr-card:hover {
  background: var(--card-hover);
  border-color: rgba(255, 107, 53, 0.3);
  transform: translateY(-4px);
}

.qr-image {
  width: 200px;
  height: 200px;
  margin: 0 auto 20px;
  background: #fff;
  border-radius: 12px;
  padding: 12px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}

.qr-image img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: block;
}

.qr-placeholder-text {
  display: none;
  color: #999;
  font-size: 14px;
  text-align: center;
  line-height: 1.6;
  font-weight: 500;
  background-image: repeating-linear-gradient(
    45deg,
    transparent,
    transparent 8px,
    rgba(0, 0, 0, 0.04) 8px,
    rgba(0, 0, 0, 0.04) 16px
  );
  width: 100%;
  height: 100%;
  border-radius: 8px;
  align-items: center;
  justify-content: center;
}

.qr-image.placeholder .qr-placeholder-text {
  display: flex;
}

.qr-card h3 {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 8px;
}

.qr-card p {
  color: var(--fg-soft);
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 16px;
}

.qr-tag {
  display: inline-block;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 12px;
  background: rgba(255, 107, 53, 0.12);
  color: var(--accent);
  border: 1px solid rgba(255, 107, 53, 0.25);
  font-weight: 500;
}

/* Footer */
.footer {
  border-top: 1px solid var(--line);
  padding: 40px 24px;
  background: rgba(0, 0, 0, 0.3);
}

.footer-inner {
  max-width: var(--maxw);
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-brand {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.footer-meta {
  text-align: right;
  color: var(--fg-mute);
  font-size: 13px;
  line-height: 1.7;
}

.footer-copy {
  color: var(--fg-mute);
  font-size: 12px;
}

/* Responsive */
@media (max-width: 768px) {
  .nav-links {
    gap: 18px;
  }
  .nav-links a {
    font-size: 13px;
  }
  .hero {
    padding: 80px 20px 60px;
  }
  .section {
    padding: 70px 20px;
  }
  .cards,
  .qr-grid {
    grid-template-columns: 1fr;
  }
  .qr-image {
    width: 220px;
    height: 220px;
  }
  .footer-inner {
    flex-direction: column;
    text-align: center;
  }
  .footer-meta {
    text-align: center;
  }
}

@media (max-width: 480px) {
  .nav-links {
    display: none;
  }
}