:root {
  --xb-blue: #1a4a8c;
  --xb-blue-dark: #0f2f5c;
  --xb-green: #3db34a;
  --xb-green-dark: #2c9a38;
  --xb-bg: #f4f6f9;
  --xb-text: #1f2733;
  --xb-muted: #5b6675;
  --xb-border: #e2e7ee;
  --xb-card: #ffffff;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: 'Noto Sans KR', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  color: var(--xb-text);
  background: var(--xb-bg);
  line-height: 1.75;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--xb-blue); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 960px; margin: 0 auto; padding: 0 18px; }

/* Header */
.site-header {
  background: linear-gradient(90deg, var(--xb-blue) 0%, var(--xb-blue) 50%, var(--xb-green) 50%, var(--xb-green) 100%);
  padding: 14px 0;
  position: sticky;
  top: 0;
  z-index: 50;
  box-shadow: 0 2px 10px rgba(15,47,92,0.18);
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand img { height: 34px; width: auto; display: block; }
.brand-name { color: #fff; font-weight: 800; font-size: 18px; letter-spacing: .3px; }
.header-date {
  color: #fff;
  font-size: 13px;
  background: rgba(255,255,255,0.18);
  padding: 5px 12px;
  border-radius: 20px;
  white-space: nowrap;
}

/* Hero */
.hero {
  background: linear-gradient(135deg, var(--xb-blue-dark) 0%, var(--xb-blue) 60%, var(--xb-green-dark) 130%);
  color: #fff;
  padding: 46px 0 40px;
  text-align: center;
}
.hero img.hero-logo {
  max-width: 320px;
  width: 70%;
  height: auto;
  border-radius: 10px;
  margin: 0 auto 22px;
  display: block;
  box-shadow: 0 8px 26px rgba(0,0,0,0.28);
}
.hero h1 { font-size: 30px; line-height: 1.35; margin-bottom: 14px; font-weight: 800; }
.hero p { font-size: 16px; color: #e6eef8; max-width: 720px; margin: 0 auto 26px; }

/* Buttons */
.btn-group { display: flex; flex-wrap: wrap; gap: 14px; justify-content: center; }
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 15px 26px;
  font-size: 16px;
  font-weight: 800;
  border-radius: 10px;
  border: none;
  cursor: pointer;
  transition: transform .12s ease, box-shadow .12s ease, filter .12s ease;
  text-align: center;
  min-width: 240px;
  color: #fff;
}
.btn:hover { text-decoration: none; transform: translateY(-2px); box-shadow: 0 10px 22px rgba(0,0,0,0.25); filter: brightness(1.05); }
.btn-primary { background: var(--xb-green); }
.btn-primary:hover { background: var(--xb-green-dark); }
.btn-apk { background: #ffffff; color: var(--xb-blue-dark); border: 2px solid #fff; }
.btn-apk:hover { background: #eef4ff; }

/* Bonus code banner */
.bonus-banner {
  background: linear-gradient(90deg, var(--xb-green) 0%, var(--xb-blue) 100%);
  color: #fff;
  border-radius: 14px;
  padding: 22px 20px;
  margin: 26px 0;
  text-align: center;
  box-shadow: 0 6px 20px rgba(26,74,140,0.2);
}
.bonus-banner h2 { font-size: 20px; margin-bottom: 8px; }
.promo-code {
  display: inline-block;
  background: #fff;
  color: var(--xb-blue-dark);
  font-weight: 900;
  font-size: 26px;
  letter-spacing: 3px;
  padding: 10px 26px;
  border-radius: 10px;
  margin: 10px 0;
  border: 2px dashed var(--xb-blue-dark);
}
.bonus-banner small { display:block; color: #eaf3ff; margin-top: 6px; }

/* Content */
main { padding: 30px 0 10px; }
.content h1, .content h2, .content h3 { color: var(--xb-blue-dark); font-weight: 800; }
.content h2 {
  font-size: 23px;
  margin: 34px 0 14px;
  padding-bottom: 8px;
  border-bottom: 3px solid var(--xb-green);
}
.content h3 { font-size: 19px; margin: 22px 0 10px; }
.content p { margin: 0 0 16px; color: var(--xb-text); }
.content ul, .content ol { margin: 0 0 18px 22px; }
.content li { margin-bottom: 8px; }

.card {
  background: var(--xb-card);
  border: 1px solid var(--xb-border);
  border-radius: 12px;
  padding: 22px 24px;
  margin-bottom: 20px;
  box-shadow: 0 1px 4px rgba(15,47,92,0.05);
}

.callout {
  background: #eef4ff;
  border-left: 4px solid var(--xb-blue);
  padding: 14px 18px;
  border-radius: 8px;
  margin: 18px 0;
  color: var(--xb-text);
}

/* Bonus grid */
.bonus-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 14px; margin: 16px 0 8px; }
.bonus-item {
  background: #fff;
  border: 1px solid var(--xb-border);
  border-top: 4px solid var(--xb-green);
  border-radius: 10px;
  padding: 16px 18px;
}
.bonus-item strong { color: var(--xb-blue-dark); display: block; margin-bottom: 6px; font-size: 16px; }
.bonus-item span { color: var(--xb-muted); font-size: 14px; }

/* Steps */
.steps { counter-reset: step; list-style: none; margin-left: 0; }
.steps li {
  position: relative;
  padding-left: 46px;
  margin-bottom: 16px;
  min-height: 34px;
}
.steps li::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0; top: 0;
  width: 32px; height: 32px;
  background: var(--xb-blue);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 800;
  font-size: 15px;
}

/* Sticky mobile CTA */
.mobile-cta {
  display: none;
  position: fixed;
  bottom: 0; left: 0; right: 0;
  background: #fff;
  border-top: 1px solid var(--xb-border);
  padding: 10px 12px;
  gap: 10px;
  z-index: 60;
  box-shadow: 0 -3px 14px rgba(0,0,0,0.12);
}
.mobile-cta .btn { min-width: 0; flex: 1; padding: 12px 8px; font-size: 14px; }

/* Footer */
.site-footer {
  background: var(--xb-blue-dark);
  color: #cdd9ea;
  padding: 30px 0;
  margin-top: 40px;
  font-size: 14px;
}
.site-footer .container { text-align: center; }
.site-footer .warn {
  background: rgba(255,255,255,0.08);
  border-radius: 10px;
  padding: 16px;
  margin-bottom: 16px;
  line-height: 1.7;
}
.site-footer a { color: #9fc0ea; }

figure { margin: 18px 0; text-align: center; }
figure img { max-width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--xb-border); }
figcaption { color: var(--xb-muted); font-size: 13px; margin-top: 8px; }

@media (max-width: 640px) {
  .hero h1 { font-size: 23px; }
  .content h2 { font-size: 20px; }
  .btn { min-width: 100%; }
  .header-date { display: none; }
  body { padding-bottom: 70px; }
  .mobile-cta { display: flex; }
}