:root { --accent: #0ea5e9; }
* { box-sizing: border-box; }
body { margin:0; font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial; color:#0b0b0e; background:#f5f5f7; }
.container { max-width: 1100px; margin: 0 auto; padding: 24px; }
.header { display:flex; align-items:center; justify-content:space-between; padding:18px 0; }
.nav a { margin-left:16px; color: var(--accent); text-decoration:none; }
.card { background:#fff; border-radius:16px; padding:22px; box-shadow: 0 6px 28px rgba(0,0,0,.06); margin-bottom:20px; }
.input { width:100%; padding:10px 12px; border:1px solid #d7d7dd; border-radius:12px; }
.btn { background:#111; color:#fff; border:none; border-radius:12px; padding:10px 14px; cursor:pointer; }
.btn:disabled { opacity:.6; cursor:not-allowed; }
.label { font-size:12px; color:#555; margin-bottom:6px; display:block; }
.row { display:grid; grid-template-columns: 1fr 1fr; gap:16px; }
.grid-4 { display:grid; grid-template-columns: repeat(4, 1fr); gap:16px; }
.footer { text-align:center; color:#666; font-size:12px; padding:24px 0; }
.help { color:#6b7280; font-size:12px; }
.h1 { font-size: 28px; font-weight: 700; margin: 6px 0 4px; }
.h2 { font-size: 20px; font-weight: 700; margin: 10px 0; }
.p { line-height: 1.6; }
.kicker { text-transform: uppercase; letter-spacing: 0.06em; font-size: 11px; color: #2563eb; }
.badge { display:inline-block; padding:4px 8px; border-radius:999px; background:#e5f2ff; color:#0369a1; font-size:11px; }


/* UI polish */
.header .brand { font-weight:800; letter-spacing:.2px; }
.header .nav a { font-weight:600; padding:6px 10px; border-radius:10px; }
.header .nav a:hover { background: #eef7ff; text-decoration: none; }
h1,h2,h3 { letter-spacing:.1px; }
.card h2.h2 { margin-top: 0; }
input.input, textarea.input, select.input { background:#fff; }
.card .smallbtn { transition: transform .08s ease; }
.card .smallbtn:active, .btn:active { transform: translateY(1px); }
@media (max-width: 720px) {
  .row { grid-template-columns: 1fr; }
}

.nav a.active { border-bottom:2px solid #111; color:#111; }


/* ---- Sticky header + smooth scroll + active nav ---- */
html { scroll-behavior: smooth; }
.header { position: sticky; top: 0; z-index: 50; background: rgba(245,245,247,.9); backdrop-filter: blur(8px); border-bottom: 1px solid #eaeaf0; }
.nav a.active { background:#111; color:#fff; }
[id] { scroll-margin-top: 76px; }
.scrolled .header { box-shadow: 0 10px 30px rgba(0,0,0,.06); }