:root{
  --primary:#0a5cff;
  --primary-dark:#0040c2;
  --accent:#22d3ee;
  --bg:#f7faff;
  --bg-2:#ffffff;
  --text:#0b1730;
  --muted:#5b6781;
  --border:#e5ecf7;
  --success:#10b981;
  --warn:#f59e0b;
  --radius:14px;
  --shadow:0 8px 24px rgba(10,92,255,.08);
  --shadow-lg:0 16px 40px rgba(10,92,255,.14);
  --grad:linear-gradient(135deg,#0a5cff 0%,#22d3ee 100%);
}
*{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
body{
  font-family:'Pretendard','Apple SD Gothic Neo','Noto Sans KR',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
  color:var(--text);
  background:var(--bg);
  line-height:1.65;
  -webkit-font-smoothing:antialiased;
}
img{max-width:100%;height:auto;display:block;border-radius:var(--radius)}
a{color:var(--primary);text-decoration:none}
a:hover{text-decoration:underline}

/* Layout */
.container{max-width:1120px;margin:0 auto;padding:0 20px}
section{padding:64px 0}
h1,h2,h3{line-height:1.25;letter-spacing:-.02em;color:var(--text)}
h1{font-size:clamp(28px,4.6vw,46px);font-weight:800}
h2{font-size:clamp(22px,3.2vw,32px);font-weight:800;margin-bottom:16px}
h3{font-size:18px;font-weight:700;margin-bottom:8px}
p{color:var(--muted)}
.lead{font-size:18px;color:#33415c}

/* Header */
.site-header{
  position:sticky;top:0;z-index:50;
  background:rgba(255,255,255,.85);
  backdrop-filter:saturate(180%) blur(12px);
  border-bottom:1px solid var(--border);
}
.nav{display:flex;align-items:center;justify-content:space-between;padding:14px 20px;max-width:1120px;margin:0 auto}
.brand{display:flex;align-items:center;gap:10px;font-weight:800;font-size:18px;color:var(--text)}
.brand img{width:32px;height:32px;border-radius:8px}
.nav-links{display:flex;gap:22px}
.nav-links a{color:var(--text);font-weight:600;font-size:15px}

/* Hero */
.hero{background:linear-gradient(180deg,#eaf2ff 0%,#f7faff 100%);padding:72px 0 56px}
.hero-grid{display:grid;grid-template-columns:1.1fr 1fr;gap:48px;align-items:center}
.eyebrow{display:inline-block;background:#e0ecff;color:var(--primary-dark);font-weight:700;padding:6px 12px;border-radius:999px;font-size:13px;margin-bottom:14px}
.hero p.lead{margin-top:18px;max-width:540px}
.cta-row{display:flex;gap:12px;margin-top:26px;flex-wrap:wrap}
.btn{
  display:inline-flex;align-items:center;gap:8px;
  padding:13px 22px;border-radius:12px;font-weight:700;font-size:15px;
  cursor:pointer;border:none;transition:transform .15s ease,box-shadow .15s ease;
}
.btn-primary{background:var(--grad);color:#fff;box-shadow:var(--shadow)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:var(--shadow-lg);text-decoration:none}
.btn-outline{background:#fff;color:var(--primary-dark);border:1.5px solid var(--primary)}
.btn-outline:hover{background:#f0f6ff;text-decoration:none}

/* Coupon cards */
.coupon-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:24px}
.coupon{
  position:relative;background:#fff;border:1.5px dashed var(--primary);border-radius:16px;
  padding:22px;display:flex;flex-direction:column;gap:12px;
  transition:transform .2s ease,box-shadow .2s ease;
}
.coupon:hover{transform:translateY(-4px);box-shadow:var(--shadow-lg)}
.coupon .tag{display:inline-block;background:var(--grad);color:#fff;font-weight:700;font-size:12px;padding:4px 10px;border-radius:6px;width:fit-content}
.coupon .code{font-family:'JetBrains Mono','SF Mono',monospace;font-size:22px;font-weight:800;color:var(--text);letter-spacing:.5px;padding:12px;background:#f3f7ff;border-radius:10px;text-align:center}
.coupon .copy-btn{background:var(--primary);color:#fff;border:none;padding:11px;border-radius:10px;font-weight:700;cursor:pointer;font-size:14px}
.coupon .copy-btn.copied{background:var(--success)}
.coupon .desc{font-size:13px;color:var(--muted)}

/* Feature grid */
.feature-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:22px;margin-top:28px}
.feature{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:24px;box-shadow:var(--shadow)}
.feature .icon{width:44px;height:44px;border-radius:10px;background:var(--grad);display:flex;align-items:center;justify-content:center;color:#fff;font-size:22px;font-weight:800;margin-bottom:14px}

/* Image gallery */
.media-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:24px}
.media-grid figure{margin:0}
.media-grid figcaption{font-size:13px;color:var(--muted);text-align:center;margin-top:8px}

/* Table */
.table-wrap{overflow-x:auto;margin-top:18px;border-radius:var(--radius);border:1px solid var(--border);background:#fff}
table{width:100%;border-collapse:collapse;min-width:560px}
th,td{padding:14px 16px;text-align:left;border-bottom:1px solid var(--border);font-size:15px}
th{background:#f3f7ff;font-weight:700;color:var(--text)}
tr:last-child td{border-bottom:none}
td.best{color:var(--primary-dark);font-weight:700}

/* Calculator */
.calc{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:28px;box-shadow:var(--shadow);margin-top:18px}
.calc-row{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.calc label{font-weight:600;font-size:14px;color:var(--text);display:block;margin-bottom:6px}
.calc input,.calc select{
  width:100%;padding:12px 14px;border:1.5px solid var(--border);border-radius:10px;
  font-size:15px;background:#fafcff;
}
.calc input:focus,.calc select:focus{outline:none;border-color:var(--primary)}
.calc-result{
  margin-top:18px;padding:20px;border-radius:12px;
  background:linear-gradient(135deg,#eaf2ff,#e0f7fa);
  font-size:17px;color:var(--text);font-weight:600;
}
.calc-result strong{color:var(--primary-dark);font-size:22px}

/* FAQ */
.faq-item{background:#fff;border:1px solid var(--border);border-radius:12px;padding:18px 22px;margin-bottom:12px}
.faq-item summary{cursor:pointer;font-weight:700;font-size:16px;list-style:none;display:flex;justify-content:space-between;align-items:center}
.faq-item summary::-webkit-details-marker{display:none}
.faq-item summary::after{content:'+';font-size:22px;color:var(--primary);font-weight:400}
.faq-item[open] summary::after{content:'−'}
.faq-item p{margin-top:12px;font-size:15px;line-height:1.7}

/* Steps */
.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:18px;margin-top:24px}
.step{background:#fff;border:1px solid var(--border);border-radius:var(--radius);padding:22px;text-align:center}
.step .num{display:inline-flex;width:36px;height:36px;border-radius:50%;background:var(--grad);color:#fff;font-weight:800;align-items:center;justify-content:center;margin-bottom:10px}

/* Footer */
footer{background:#0b1730;color:#cbd5e1;padding:42px 0;margin-top:60px}
footer .container{display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:14px}
footer a{color:#9fb4d4}
footer p{color:#94a3b8;font-size:14px}

/* Toast */
.toast{
  position:fixed;bottom:30px;left:50%;transform:translateX(-50%) translateY(20px);
  background:var(--text);color:#fff;padding:12px 22px;border-radius:10px;font-weight:600;
  opacity:0;transition:all .3s ease;z-index:100;font-size:14px;
}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}

/* Responsive */
@media (max-width:820px){
  section{padding:44px 0}
  .hero{padding:44px 0 36px}
  .hero-grid{grid-template-columns:1fr;gap:28px}
  .coupon-grid,.feature-grid,.media-grid{grid-template-columns:1fr}
  .steps{grid-template-columns:repeat(2,1fr)}
  .calc-row{grid-template-columns:1fr}
  .nav-links{display:none}
}