:root {
  color-scheme: light dark;
  --page: #f5fbf9;
  --page-deep: #e5f7f3;
  --surface: rgba(255, 255, 255, 0.78);
  --ink: #08282a;
  --muted: #456164;
  --accent: #087f84;
  --rule: rgba(8, 40, 42, 0.12);
  --shadow: 0 24px 80px rgba(1, 76, 80, 0.10);
}

@media (prefers-color-scheme: dark) {
  :root {
    --page: #061718;
    --page-deep: #0a292a;
    --surface: rgba(10, 42, 43, 0.72);
    --ink: #f2fffc;
    --muted: #b4cdca;
    --accent: #65d7d4;
    --rule: rgba(224, 255, 251, 0.14);
    --shadow: 0 24px 80px rgba(0, 0, 0, 0.28);
  }
}

* { box-sizing: border-box; }

html { background: var(--page); }

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at 78% 16%, rgba(91, 218, 211, 0.18), transparent 30rem),
    linear-gradient(160deg, var(--page) 0%, var(--page-deep) 100%);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", sans-serif;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); }

.shell {
  width: min(760px, calc(100% - 40px));
  margin: 0 auto;
  padding: 32px 0 72px;
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  min-height: 48px;
}

.brand {
  color: var(--ink);
  font-weight: 700;
  letter-spacing: -0.02em;
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 18px;
  font-size: 0.9rem;
}

.nav-links a { text-decoration: none; }

main { padding-top: clamp(56px, 10vw, 104px); }

.mark {
  width: 48px;
  height: 12px;
  margin-bottom: 30px;
  border-radius: 999px;
  background: var(--accent);
}

h1 {
  max-width: 680px;
  margin: 0;
  font-size: clamp(3rem, 9vw, 6.2rem);
  font-weight: 650;
  letter-spacing: -0.065em;
  line-height: 0.94;
}

.lead {
  max-width: 590px;
  margin: 30px 0 0;
  color: var(--muted);
  font-size: clamp(1.2rem, 3vw, 1.55rem);
  line-height: 1.48;
}

.card {
  margin-top: 52px;
  padding: clamp(24px, 5vw, 42px);
  border: 1px solid var(--rule);
  border-radius: 28px;
  background: var(--surface);
  box-shadow: var(--shadow);
  backdrop-filter: blur(20px);
}

h2 {
  margin: 0 0 16px;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

h3 {
  margin: 32px 0 10px;
  font-size: 1rem;
}

p, li {
  color: var(--muted);
  line-height: 1.62;
}

p { margin: 0 0 18px; }

ul {
  margin: 0;
  padding-left: 1.25rem;
}

.plain-list {
  display: grid;
  gap: 0;
  padding: 0;
  list-style: none;
}

.plain-list li {
  padding: 15px 0;
  border-bottom: 1px solid var(--rule);
}

.plain-list li:last-child { border-bottom: 0; }

.cta {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  margin-top: 8px;
  padding: 0 20px;
  border-radius: 999px;
  color: white;
  background: var(--accent);
  font-weight: 650;
  text-decoration: none;
}

footer {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 16px;
  margin-top: 56px;
  padding-top: 24px;
  border-top: 1px solid var(--rule);
  color: var(--muted);
  font-size: 0.88rem;
}

@media (max-width: 560px) {
  .shell { width: min(100% - 28px, 760px); }
  nav { align-items: flex-start; }
  .nav-links { flex-direction: column; gap: 8px; text-align: right; }
  .card { border-radius: 22px; }
}