:root {
  --bg: #0b0f16;
  --bg-2: #0e131b;
  --surface: #121824;
  --card: #171f2c;
  --muted: #94a3b8;
  --text: #e6eef9;
  --primary: #19e3c6;
  --accent: #4aa3ff;
  --danger: #ff5c7a;
  --shadow: 0 10px 30px rgba(0,0,0,.35);
  --radius: 16px;
  --radius-sm: 12px;
  --radius-lg: 22px;
  --container: 1200px;
  --font-sans: "Inter","Segoe UI",system-ui,-apple-system,"Helvetica Neue",Arial,"Noto Sans",sans-serif;
  --font-serif: "Merriweather","Georgia","Times New Roman",serif;
}

html {
  box-sizing: border-box;
  scroll-behavior: smooth;
}
*, *::before, *::after { box-sizing: inherit; }

body {
  margin: 0;
  color: var(--text);
  background: radial-gradient(1200px 600px at 50% -100px, rgba(25,227,198,.25), transparent 60%) , var(--bg);
  font-family: var(--font-sans);
  line-height: 1.6;
}

img { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:focus, button:focus, [tabindex]:focus { outline: 2px solid var(--primary); outline-offset: 3px; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: -9999px;
}
.skip-link:focus {
  left: 16px;
  top: 16px;
  background: var(--surface);
  color: var(--text);
  padding: 10px 14px;
  border-radius: 8px;
  box-shadow: var(--shadow);
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 20px;
}

header.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(140%) blur(10px);
  background: linear-gradient(180deg, rgba(18,24,36,.85), rgba(18,24,36,.65));
  border-bottom: 1px solid rgba(148,163,184,.15);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 64px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  letter-spacing: .2px;
}
.brand .dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--primary);
  box-shadow: 0 0 0 4px rgba(25,227,198,.2);
}
.nav {
  display: flex;
  align-items: center;
  gap: 22px;
}
.nav a {
  color: var(--text);
  opacity: .9;
}
.nav a:hover { color: var(--primary); }
.menu-toggle {
  display: none;
  border: 0;
  background: var(--surface);
  color: var(--text);
  border-radius: 10px;
  padding: 10px 12px;
}
.mobile-nav {
  display: none;
  padding: 10px 0 20px;
}
.mobile-nav.open { display: block; }
.mobile-nav a { display: block; padding: 12px 6px; color: var(--text); }

.hero {
  position: relative;
  padding: 80px 0 40px;
  background:
    radial-gradient(600px 280px at 50% 0, rgba(25,227,198,.25), transparent 70%),
    radial-gradient(400px 180px at 10% -50px, rgba(74,163,255,.22), transparent 70%),
    radial-gradient(400px 180px at 90% -50px, rgba(74,163,255,.22), transparent 70%);
}
.hero .content {
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
}
.kicker {
  color: var(--primary);
  font-weight: 600;
  letter-spacing: .3px;
}
.hero h1 {
  font-size: clamp(28px, 5vw, 42px);
  margin: 12px 0 10px;
}
.hero p {
  color: var(--muted);
  font-size: clamp(16px, 3.6vw, 18px);
  margin: 0 0 22px;
}
.cta {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  background: linear-gradient(180deg, var(--primary), #0fd2b2);
  color: #041015;
  font-weight: 700;
  padding: 14px 18px;
  border-radius: 12px;
  box-shadow: 0 8px 20px rgba(25,227,198,.35);
}
.cta:hover { filter: brightness(1.05); transform: translateY(-1px); }

.cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  margin: 30px 0 10px;
}
.card {
  background: linear-gradient(180deg, var(--card), #0f1723);
  border: 1px solid rgba(148,163,184,.18);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}
.card .thumb {
  aspect-ratio: 16/10;
  background: linear-gradient(120deg, rgba(74,163,255,.25), rgba(25,227,198,.25));
}
.card .body {
  padding: 16px;
}
.card h3 {
  margin: 0 0 8px;
  font-size: 18px;
}
.card p {
  margin: 0 0 14px;
  color: var(--muted);
  font-size: 15px;
}
.card .meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}
.card .btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #0c1a22;
  color: var(--text);
  border: 1px solid rgba(148,163,184,.2);
  padding: 10px 12px;
  border-radius: 10px;
}
.card .btn:hover { border-color: var(--primary); color: var(--primary); }

.section {
  padding: 60px 0;
}
.section.light {
  background: #f8fafc;
  color: #0b0f16;
}
.section.light .muted { color: #334155; }

.features-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}
.feature {
  background: var(--surface);
  border: 1px solid rgba(148,163,184,.18);
  border-radius: var(--radius);
  padding: 18px;
  box-shadow: var(--shadow);
}
.feature h4 { margin: 0 0 8px; font-size: 18px; }
.feature p { margin: 0; color: var(--muted); }

.panel-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.panel {
  background: linear-gradient(180deg, #101826, #0c131f);
  border: 1px solid rgba(148,163,184,.18);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
}
.panel .title { font-weight: 700; }
.panel .desc { color: var(--muted); font-size: 14px; }

.tagbar {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}
.tag {
  background: #0c1a22;
  color: var(--text);
  border-radius: 999px;
  border: 1px solid rgba(148,163,184,.2);
  padding: 8px 12px;
  font-size: 13px;
}

footer.site-footer {
  padding: 40px 0 60px;
  border-top: 1px solid rgba(148,163,184,.15);
  background: var(--bg-2);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  text-align: center;
}
.footer-nav {
  display: flex;
  justify-content: center;
  gap: 18px;
}
.copyright {
  color: var(--muted);
  font-size: 14px;
}

main.article {
  padding: 32px 0 60px;
}
.article header {
  margin-bottom: 20px;
}
.article h1 {
  font-size: clamp(26px, 5vw, 38px);
  margin: 0 0 12px;
}
.article .lede {
  color: var(--muted);
  font-size: 18px;
}
.article .content {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin-top: 26px;
}
.article img.hero {
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}
.article h2 { margin: 24px 0 10px; font-size: 22px; }
.article p { margin: 0; }
.article ul, .article ol { padding-left: 22px; }
.article table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border: 1px solid rgba(148,163,184,.18);
  border-radius: var(--radius);
  overflow: hidden;
}
.article th, .article td {
  border-bottom: 1px solid rgba(148,163,184,.18);
  padding: 12px 14px;
  text-align: left;
}
.faq {
  margin-top: 24px;
  border-top: 1px solid rgba(148,163,184,.18);
  padding-top: 10px;
}
.faq details {
  background: var(--card);
  border: 1px solid rgba(148,163,184,.18);
  border-radius: var(--radius-sm);
  padding: 12px 14px;
  margin: 10px 0;
}
.faq summary {
  cursor: pointer;
  font-weight: 600;
}

@media (min-width: 640px) {
  .cards { grid-template-columns: repeat(2, 1fr); }
  .features-grid { grid-template-columns: repeat(3, 1fr); }
  .footer-inner { grid-template-columns: repeat(3, 1fr); text-align: left; }
}
@media (min-width: 960px) {
  .cards { grid-template-columns: repeat(3, 1fr); }
  .header-inner { min-height: 72px; }
  .hero { padding: 110px 0 60px; }
  .features-grid { grid-template-columns: repeat(4, 1fr); }
  .panel-grid { grid-template-columns: repeat(4, 1fr); }
  .article .content { grid-template-columns: 1fr 320px; }
}
@media (max-width: 820px) {
  .nav { display: none; }
  .menu-toggle { display: inline-flex; }
}