:root {
  --bg-top: #e8f4f8;
  --bg-bottom: #f7fbfc;
  --ink: #12232b;
  --muted: #4a6670;
  --accent: #0a7ea4;
  --accent-deep: #06607d;
  --surface: rgba(255, 255, 255, 0.88);
  --line: rgba(10, 126, 164, 0.18);
  --radius: 18px;
  --shadow: 0 18px 50px rgba(18, 55, 70, 0.08);
  --font: "Source Sans 3", system-ui, sans-serif;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font);
  color: var(--ink);
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(10, 126, 164, 0.18), transparent 60%),
    radial-gradient(900px 420px at 100% 0%, rgba(80, 170, 190, 0.16), transparent 55%),
    linear-gradient(180deg, var(--bg-top), var(--bg-bottom));
  line-height: 1.6;
}

.wrap {
  width: min(760px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2.25rem 0 4rem;
}

.topnav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.1rem;
  margin-bottom: 1.5rem;
  font-size: 0.95rem;
}

.topnav a {
  color: var(--accent-deep);
  text-decoration: none;
  font-weight: 600;
}

.topnav a:hover { text-decoration: underline; }

.brand-name {
  margin: 0 0 0.25rem;
  font-size: clamp(2rem, 5vw, 2.5rem);
  font-weight: 700;
  color: var(--accent-deep);
  letter-spacing: -0.02em;
}

.brand-sub {
  margin: 0 0 1.5rem;
  color: var(--muted);
  font-size: 1.05rem;
}

.panel {
  background: var(--surface);
  backdrop-filter: blur(10px);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: clamp(1.25rem, 3vw, 1.85rem);
  margin-bottom: 1rem;
}

h1 {
  margin: 0 0 0.5rem;
  font-size: clamp(1.4rem, 3.5vw, 1.75rem);
}

.updated {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.95rem;
}

h2 {
  margin: 1.5rem 0 0.55rem;
  font-size: 1.12rem;
  color: var(--accent-deep);
}

h2:first-of-type { margin-top: 0.35rem; }

p, li {
  color: var(--muted);
  margin: 0 0 0.7rem;
}

ul {
  margin: 0 0 0.5rem;
  padding-inline-start: 1.2rem;
}

li { margin-bottom: 0.4rem; }

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

.note {
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border-radius: 12px;
  background: rgba(10, 126, 164, 0.08);
  color: var(--muted);
  font-size: 0.95rem;
}

footer {
  margin-top: 1.5rem;
  text-align: center;
  color: var(--muted);
  font-size: 0.92rem;
}