:root {
  --bg: #f4f7fb;
  --surface: #ffffff;
  --ink: #0f1f3a;
  --muted: #4e607f;
  --brand: #0b5fff;
  --brand-soft: #dce7ff;
  --border: #dfe7f3;
  --shadow: 0 10px 30px rgba(14, 34, 77, 0.08);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
}

body {
  font-family: "Segoe UI", "Helvetica Neue", Arial, sans-serif;
  background: radial-gradient(circle at top right, #e6efff 0%, #f4f7fb 40%, #f4f7fb 100%);
  color: var(--ink);
  line-height: 1.65;
}

.container {
  width: min(980px, calc(100% - 2rem));
  margin: 0 auto;
}

.hero {
  background: linear-gradient(140deg, #0b1536 0%, #0d2554 45%, #0b5fff 100%);
  color: #fff;
  padding: 3.5rem 0 2.4rem;
  box-shadow: var(--shadow);
}

.eyebrow {
  margin: 0;
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  opacity: 0.82;
}

h1 {
  margin: 0.45rem 0 0.7rem;
  font-size: clamp(1.8rem, 2.8vw, 2.9rem);
  line-height: 1.2;
}

.subtitle {
  max-width: 72ch;
  margin: 0 0 1rem;
  color: rgba(255, 255, 255, 0.92);
}

.meta {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
  font-size: 0.92rem;
  color: rgba(255, 255, 255, 0.92);
}

.content {
  padding: 1.5rem 0 3rem;
}

.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.1rem 1.2rem;
  margin: 0 0 1rem;
  box-shadow: 0 3px 10px rgba(15, 31, 58, 0.04);
}

.card h2 {
  margin: 0 0 0.45rem;
  font-size: 1.17rem;
  color: var(--ink);
}

.card h3 {
  margin: 0.8rem 0 0.35rem;
  font-size: 1rem;
  color: #163d8f;
}

.card p {
  margin: 0.45rem 0;
  color: var(--muted);
}

ul,
ol {
  margin: 0.45rem 0 0.45rem 1.2rem;
  padding: 0;
}

li {
  margin: 0.25rem 0;
  color: var(--muted);
}

.toc ol {
  columns: 2;
  column-gap: 2rem;
}

.toc a {
  color: #1848ad;
  text-decoration: none;
}

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

.notice {
  border-left: 4px solid #f4b400;
  background: #fffcee;
}

.contact ul {
  margin-left: 1rem;
}

.footer {
  border-top: 1px solid var(--border);
  background: #edf2fb;
  padding: 1.1rem 0 1.4rem;
  color: #4c6186;
  font-size: 0.9rem;
}

@media (max-width: 760px) {
  .hero {
    padding-top: 2.3rem;
  }

  .toc ol {
    columns: 1;
  }

  .card {
    padding: 1rem;
  }
}