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

:root {
  --bg:           #0a0e1a;
  --surface:      #111827;
  --surface-high: #1a2235;
  --border:       #222840;
  --gold:         #c9a227;
  --gold-light:   #ffd97a;
  --gold-dim:     #8a6d10;
  --text:         #e8ecf4;
  --text-muted:   #b0b8cc;
  --blue:         #4a9eff;
  --font-head:    'Space Grotesk', sans-serif;
  --font-body:    'Inter', sans-serif;
  --max-w:        1200px;
  --nav-h:        68px;
  --radius-sm:    4px;
  --radius-md:    10px;
  --radius-lg:    16px;
  --radius-full:  9999px;
}

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
}

/* ===== NAVBAR ===== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  height: var(--nav-h);
  background: rgba(10, 14, 26, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  z-index: 1000;
  transition: background 0.3s;
}

.navbar.scrolled {
  background: rgba(10, 14, 26, 0.97);
}

.nav-inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 24px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

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

.logo-icon {
  font-size: 22px;
  color: var(--gold);
  font-family: var(--font-head);
  font-weight: 700;
}

.logo-text {
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

.lang-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  padding: 4px 12px;
}

.lang-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  padding: 2px 4px;
  transition: color 0.2s;
}

.lang-btn.active {
  color: var(--gold);
}

.lang-sep {
  color: var(--border);
  font-size: 12px;
}

.btn-ghost {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  padding: 7px 18px;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s;
}

.btn-ghost:hover {
  border-color: var(--gold);
  color: var(--gold);
}

/* ===== BUTTONS ===== */
.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--gold);
  color: var(--bg);
  font-family: var(--font-head);
  font-weight: 700;
  font-size: 16px;
  padding: 14px 36px;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
  letter-spacing: 0.01em;
  text-decoration: none;
}

.btn-primary:hover {
  background: var(--gold-light);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(201, 162, 39, 0.35);
}

.btn-primary.btn-lg {
  font-size: 18px;
  padding: 18px 48px;
}

/* ===== HERO ===== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: calc(var(--nav-h) + 40px) 24px 80px;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  pointer-events: none;
}

.grid-overlay {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(201, 162, 39, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(201, 162, 39, 0.04) 1px, transparent 1px);
  background-size: 60px 60px;
}

.coin-float {
  position: absolute;
  font-size: 48px;
  opacity: 0.06;
  animation: float 8s ease-in-out infinite;
  color: var(--gold);
  font-family: var(--font-head);
}

.coin-1 { top: 20%; left: 10%; animation-delay: 0s; }
.coin-2 { top: 30%; right: 12%; animation-delay: 2s; font-size: 40px; }
.coin-3 { bottom: 25%; left: 15%; animation-delay: 4s; font-size: 36px; }
.coin-4 { bottom: 30%; right: 8%; animation-delay: 1s; font-size: 44px; }

@keyframes float {
  0%, 100% { transform: translateY(0px) rotate(0deg); }
  50% { transform: translateY(-20px) rotate(5deg); }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 760px;
}

.hero-badge {
  display: inline-block;
  background: rgba(201, 162, 39, 0.12);
  border: 1px solid rgba(201, 162, 39, 0.3);
  color: var(--gold);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 6px 16px;
  border-radius: var(--radius-full);
  margin-bottom: 28px;
}

.hero-title {
  font-family: var(--font-head);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 24px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.line-en {
  font-size: clamp(36px, 5vw, 60px);
  color: var(--text);
  letter-spacing: -0.03em;
}

.line-zh {
  font-size: clamp(24px, 3.5vw, 44px);
  color: var(--gold);
  letter-spacing: 0.02em;
}

.hero-sub {
  font-size: 17px;
  color: var(--text-muted);
  margin-bottom: 40px;
  line-height: 1.8;
}

.sub-zh {
  color: rgba(176, 184, 204, 0.7);
  font-size: 15px;
}

.hero-note {
  margin-top: 16px;
  font-size: 13px;
  color: var(--text-muted);
  opacity: 0.6;
}

/* ===== TRUST BADGES ===== */
.trust-section {
  padding: 0 0 80px;
}

.trust-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: -40px;
}

.trust-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px 24px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
  transition: border-color 0.2s, transform 0.2s;
}

.trust-card:hover {
  border-color: var(--gold-dim);
  transform: translateY(-3px);
}

.trust-icon {
  font-size: 28px;
  line-height: 1;
  flex-shrink: 0;
}

.trust-title {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 16px;
  color: var(--text);
  margin-bottom: 2px;
}

.trust-title-zh {
  font-size: 13px;
  color: var(--gold);
  margin-bottom: 6px;
}

.trust-body p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ===== HOW IT WORKS ===== */
.how-section {
  padding: 80px 0;
  border-top: 1px solid var(--border);
}

.section-heading {
  text-align: center;
  margin-bottom: 56px;
}

.section-heading h2 {
  font-family: var(--font-head);
  font-size: clamp(26px, 3vw, 36px);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.heading-zh {
  color: var(--gold);
  margin-left: 12px;
}

.steps-grid {
  display: flex;
  align-items: center;
  gap: 0;
  justify-content: center;
}

.step-card {
  flex: 1;
  max-width: 280px;
  text-align: center;
  padding: 32px 24px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: border-color 0.2s;
}

.step-card:hover {
  border-color: var(--gold-dim);
}

.step-connector {
  width: 60px;
  height: 1px;
  background: linear-gradient(90deg, var(--border), var(--gold-dim), var(--border));
  flex-shrink: 0;
}

.step-num {
  font-family: var(--font-head);
  font-size: 40px;
  font-weight: 700;
  color: var(--border);
  margin-bottom: 12px;
}

.step-icon {
  font-size: 32px;
  margin-bottom: 16px;
}

.step-title {
  font-family: var(--font-head);
  font-weight: 600;
  font-size: 16px;
  margin-bottom: 4px;
}

.step-title-zh {
  font-size: 13px;
  color: var(--gold);
  margin-bottom: 10px;
}

.step-card p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 1.5;
}

.how-cta {
  text-align: center;
  margin-top: 48px;
}

/* ===== SUPPORTED ASSETS ===== */
.assets-section {
  padding: 60px 0;
  border-top: 1px solid var(--border);
}

.assets-label {
  text-align: center;
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 24px;
}

.coins-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  justify-content: center;
}

.coin-chip {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  padding: 8px 20px;
  font-size: 14px;
  font-weight: 500;
  transition: border-color 0.2s, color 0.2s;
}

.coin-chip:hover {
  border-color: var(--gold-dim);
  color: var(--gold-light);
}

.coin-sym {
  color: var(--gold);
  font-size: 16px;
}

.more-chip {
  color: var(--text-muted);
  font-size: 13px;
}

/* ===== FOOTER ===== */
.footer {
  background: var(--surface);
  border-top: 1px solid var(--border);
  padding: 48px 0 24px;
}

.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 40px;
  padding-bottom: 32px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 24px;
}

.footer-tagline {
  font-size: 13px;
  color: var(--text-muted);
  margin-top: 8px;
}

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

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

.footer-links a:hover {
  color: var(--gold);
}

.footer-powered {
  text-align: right;
  font-size: 13px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

.transak-badge {
  background: rgba(201, 162, 39, 0.12);
  border: 1px solid rgba(201, 162, 39, 0.3);
  color: var(--gold);
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.footer-copy {
  text-align: center;
  font-size: 12px;
  color: var(--text-muted);
  opacity: 0.5;
}

/* ===== MODAL ===== */
.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(6px);
  z-index: 2000;
  align-items: center;
  justify-content: center;
}

.modal-overlay.open {
  display: flex;
}

.modal-box {
  position: relative;
  width: 480px;
  height: 650px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

.modal-close {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 10;
  background: var(--surface-high);
  border: 1px solid var(--border);
  color: var(--text-muted);
  width: 32px;
  height: 32px;
  border-radius: var(--radius-full);
  cursor: pointer;
  font-size: 14px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.2s, border-color 0.2s;
}

.modal-close:hover {
  color: var(--gold);
  border-color: var(--gold-dim);
}

#transak-iframe {
  width: 100%;
  height: 100%;
  border: none;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .trust-grid {
    grid-template-columns: 1fr;
    margin-top: -20px;
  }

  .steps-grid {
    flex-direction: column;
    gap: 20px;
  }

  .step-connector {
    width: 1px;
    height: 40px;
    background: linear-gradient(180deg, var(--border), var(--gold-dim), var(--border));
  }

  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 24px;
  }

  .footer-links {
    justify-content: center;
  }

  .footer-powered {
    justify-content: center;
  }

  .modal-box {
    width: calc(100vw - 32px);
    height: calc(100vh - 80px);
  }

  .nav-right .btn-ghost {
    display: none;
  }
}