:root {
  color-scheme: light dark;
  --accent: #197f9d;
  --accent-soft: #d9f3f8;
  --ink: #142126;
  --muted: #5c6b70;
  --surface: rgba(255, 255, 255, 0.72);
  --line: rgba(20, 33, 38, 0.10);
  --background: #f4fafb;
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Helvetica Neue", sans-serif;
  font-synthesis: none;
}

* { box-sizing: border-box; }

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

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 0%, rgba(50, 180, 211, 0.18), transparent 34rem),
    radial-gradient(circle at 90% 20%, rgba(136, 210, 185, 0.13), transparent 30rem),
    var(--background);
  font-size: 17px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

main, footer {
  width: min(720px, calc(100% - 40px));
  margin-inline: auto;
}

main { padding: 72px 0 44px; }
footer { padding: 0 0 52px; color: var(--muted); font-size: 14px; }

.eyebrow {
  margin: 0 0 10px;
  color: var(--accent);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

h1 {
  max-width: 12ch;
  margin: 0;
  font-size: clamp(2.6rem, 9vw, 4.7rem);
  line-height: 0.98;
  letter-spacing: -0.055em;
}

h2 {
  margin: 2.3rem 0 0.55rem;
  font-size: 1.35rem;
  line-height: 1.2;
  letter-spacing: -0.018em;
}

p, li { max-width: 68ch; }
p { margin: 0.6rem 0; }
ul { padding-left: 1.25rem; }
li { margin: 0.45rem 0; }
li::marker { color: var(--accent); }

a {
  color: var(--accent);
  text-decoration-thickness: 0.08em;
  text-underline-offset: 0.16em;
}

.meta {
  margin-top: 16px;
  color: var(--muted);
  font-size: 14px;
}

.summary, .notice {
  margin: 32px 0;
  padding: 22px 24px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--surface);
  box-shadow: 0 16px 44px rgba(26, 90, 105, 0.08);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
}

.summary h2, .notice h2 { margin-top: 0; }
.notice { border-left: 4px solid var(--accent); }

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

@media (prefers-color-scheme: dark) {
  :root {
    --accent: #73d1e7;
    --accent-soft: #163c45;
    --ink: #f0f6f7;
    --muted: #a1b0b4;
    --surface: rgba(21, 36, 41, 0.76);
    --line: rgba(225, 246, 250, 0.11);
    --background: #0d171a;
  }

  body {
    background:
      radial-gradient(circle at 15% 0%, rgba(36, 145, 171, 0.24), transparent 34rem),
      radial-gradient(circle at 90% 20%, rgba(67, 138, 115, 0.14), transparent 30rem),
      var(--background);
  }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

@media (max-width: 520px) {
  main { padding-top: 52px; }
  .summary, .notice { padding: 19px; border-radius: 18px; }
}