:root {
  --ink: #0c1f2e;
  --body: #33454f;
  --muted: #6b7f96;
  --line: #e2eef3;
  --teal: #6dd0db;
  --teal-dark: #0c86a8;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: #fff;
  color: var(--body);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  -webkit-font-smoothing: antialiased;
  line-height: 1.65;
}

/* header */
.lg-top {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.92);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(207, 227, 236, 0.6);
}
.lg-top__inner {
  max-width: 72rem;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 16px;
}
.lg-top img { height: 28px; width: auto; display: block; }
.lg-top a.lg-back {
  margin-left: auto;
  font-size: 14px;
  font-weight: 700;
  color: var(--teal-dark);
  text-decoration: none;
}
.lg-top a.lg-back:hover { text-decoration: underline; }

/* hero */
.lg-hero {
  background: linear-gradient(180deg, #04121d 0%, #0a2133 45%, #0f3049 100%);
  color: #fff;
  padding: 68px 24px 74px;
  text-align: center;
}
.lg-hero p.eyebrow {
  font-size: 12px;
  font-weight: 800;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--teal);
  margin-bottom: 14px;
}
.lg-hero h1 {
  font-size: clamp(30px, 5vw, 44px);
  font-weight: 800;
  letter-spacing: -0.5px;
  line-height: 1.15;
}
.lg-hero .lg-date {
  margin-top: 14px;
  font-size: 14px;
  color: rgba(214, 234, 242, 0.78);
}

/* layout */
.lg-wrap {
  max-width: 72rem;
  margin: 0 auto;
  padding: 54px 24px 90px;
  display: grid;
  grid-template-columns: 232px minmax(0, 1fr);
  gap: 48px;
  align-items: start;
}
.lg-toc {
  position: sticky;
  top: 84px;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 18px 20px;
  background: #f7fbfc;
}
.lg-toc h2 {
  font-size: 11px;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
  margin-bottom: 12px;
}
.lg-toc ol { list-style: none; counter-reset: toc; }
.lg-toc li { counter-increment: toc; }
.lg-toc a {
  display: block;
  padding: 5px 0;
  font-size: 13.5px;
  color: var(--body);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}
.lg-toc a:hover { color: var(--teal-dark); }
.lg-toc a::before { content: counter(toc) ". "; color: var(--muted); }

.lg-body h2 {
  margin: 42px 0 14px;
  font-size: 21px;
  font-weight: 800;
  color: var(--ink);
  letter-spacing: -0.2px;
  scroll-margin-top: 92px;
}
.lg-body h2:first-child { margin-top: 0; }
.lg-body h3 {
  margin: 24px 0 8px;
  font-size: 15.5px;
  font-weight: 800;
  color: var(--ink);
}
.lg-body p { margin: 0 0 14px; font-size: 15.5px; }
.lg-body ul { margin: 0 0 16px; padding-left: 0; list-style: none; }
.lg-body li {
  position: relative;
  padding-left: 22px;
  margin-bottom: 7px;
  font-size: 15.5px;
}
.lg-body li::before {
  content: "";
  position: absolute;
  left: 4px;
  top: 10px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--teal);
}
.lg-body a { color: var(--teal-dark); }
.lg-intro {
  border-left: 3px solid var(--teal);
  padding: 4px 0 4px 18px;
  margin-bottom: 34px;
}
.lg-intro p { font-size: 16px; }
.lg-note {
  background: #f4fafb;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px 20px;
  margin: 26px 0;
}
.lg-note p:last-child { margin-bottom: 0; }
.lg-contact {
  background: linear-gradient(160deg, #0c2231 0%, #123549 100%);
  border-radius: 18px;
  padding: 26px 28px;
  color: rgba(220, 238, 245, 0.9);
  margin-top: 12px;
}
.lg-contact h2 { color: #fff; margin-top: 0; }
.lg-contact p { color: rgba(220, 238, 245, 0.9); }
.lg-contact a { color: var(--teal); font-weight: 700; }

/* footer */
.lg-foot {
  background: #0c1f2e;
  color: #8a9db5;
  padding: 34px 24px;
  font-size: 13px;
}
.lg-foot__inner {
  max-width: 72rem;
  margin: 0 auto;
  display: flex;
  flex-wrap: wrap;
  gap: 14px 26px;
  align-items: center;
  justify-content: space-between;
}
.lg-foot a { color: #8a9db5; text-decoration: none; }
.lg-foot a:hover { color: #fff; }
.lg-foot nav { display: flex; gap: 20px; }

@media (max-width: 860px) {
  .lg-wrap { grid-template-columns: 1fr; gap: 26px; padding-top: 34px; }
  .lg-toc { position: static; }
}