:root {
  --primary: #1e3a5f;
  --accent: #1d6fce;
  --accent-lt: #2d84e8;
  --surface: #fff;
  --bg: #f0f4f9;
  --bg-dark: #0d1f35;
  --border: #c8d8eb;
  --text: #0f1f2e;
  --muted: #5a7080;
  --coming: #d97706;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--text);
  font-family: "Helvetica Neue", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic UI", Arial, sans-serif;
  line-height: 1.7;
}
a { color: var(--accent); }
nav {
  align-items: center;
  backdrop-filter: blur(8px);
  background: rgba(14, 31, 53, .96);
  border-bottom: 1px solid rgba(255, 255, 255, .08);
  display: flex;
  height: 56px;
  justify-content: space-between;
  padding: 0 32px;
  position: sticky;
  top: 0;
  z-index: 100;
}
.nav-logo { align-items: center; display: flex; gap: 10px; text-decoration: none; }
.nav-logo-mark { border-radius: 6px; display: block; flex-shrink: 0; height: auto; width: 24px; }
.nav-logo-text { color: #fff; font-size: 1rem; font-weight: 800; letter-spacing: -.02em; }
.nav-logo-text span { color: var(--accent-lt); }
.nav-links { align-items: center; display: flex; gap: 28px; list-style: none; }
.nav-links a { color: rgba(255, 255, 255, .65); font-size: .82rem; font-weight: 600; text-decoration: none; }
.nav-links a:hover { color: #fff; }
.nav-badge {
  background: rgba(217, 119, 6, .15);
  border: 1px solid rgba(217, 119, 6, .35);
  border-radius: 999px;
  color: var(--coming);
  font-size: .7rem;
  font-weight: 700;
  padding: 2px 10px;
}
.breadcrumb { background: var(--surface); border-bottom: 1px solid var(--border); }
.breadcrumb-inner { color: var(--muted); font-size: .78rem; margin: 0 auto; max-width: 760px; padding: 12px 24px; }
.breadcrumb-inner a { color: var(--muted); text-decoration: none; }
.breadcrumb-inner span { color: var(--primary); font-weight: 600; }
.breadcrumb-sep { color: var(--border) !important; margin: 0 8px; }
.hero {
  background: linear-gradient(160deg, #0b1a2e 0%, #0d2240 55%, #102d52 100%);
  overflow: hidden;
  padding: 72px 24px 64px;
  position: relative;
  text-align: center;
}
.hero::before {
  background: radial-gradient(circle, rgba(29, 111, 206, .18) 0%, transparent 70%);
  content: "";
  height: 800px;
  left: 50%;
  pointer-events: none;
  position: absolute;
  top: -120px;
  transform: translateX(-50%);
  width: 800px;
}
.hero-tag {
  background: rgba(29, 111, 206, .18);
  border-radius: 999px;
  color: var(--accent-lt);
  display: inline-block;
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .1em;
  margin-bottom: 22px;
  padding: 5px 14px;
  position: relative;
}
.hero h1 {
  color: #fff;
  font-size: clamp(1.7rem, 4.5vw, 2.8rem);
  font-weight: 900;
  letter-spacing: -.03em;
  line-height: 1.25;
  margin: 0 auto 18px;
  max-width: 780px;
  position: relative;
}
.hero-sub {
  color: rgba(255, 255, 255, .65);
  font-size: clamp(.98rem, 2.2vw, 1.1rem);
  line-height: 1.8;
  margin: 0 auto;
  max-width: 650px;
  position: relative;
}
.article { background: var(--surface); }
.article-inner { margin: 0 auto; max-width: 760px; padding: 64px 24px; }
.article-inner h2 {
  color: var(--primary);
  font-size: clamp(1.35rem, 3vw, 1.7rem);
  font-weight: 900;
  letter-spacing: -.02em;
  line-height: 1.4;
  margin: 48px 0 16px;
}
.article-inner h2:first-child { margin-top: 0; }
.article-inner h3 { color: var(--primary); font-size: 1.08rem; font-weight: 800; margin: 28px 0 10px; }
.article-inner p { color: #2a3a4a; font-size: 1rem; line-height: 1.95; margin-bottom: 16px; }
.article-inner ul, .article-inner ol { margin: 0 0 18px; padding-left: 22px; }
.article-inner li { color: #2a3a4a; line-height: 1.9; margin-bottom: 8px; }
.lead { color: var(--muted) !important; font-size: 1.05rem !important; }
.toc, .callout {
  background: var(--bg);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: 8px;
  margin: 24px 0;
  padding: 20px 24px;
}
.toc strong { color: var(--primary); display: block; margin-bottom: 8px; }
.toc ol { margin-bottom: 0; }
.callout p:last-child { margin-bottom: 0; }
.comparison { border-collapse: collapse; display: block; margin: 24px 0; overflow-x: auto; width: 100%; }
.comparison th, .comparison td { border: 1px solid var(--border); min-width: 130px; padding: 12px; text-align: left; vertical-align: top; }
.comparison th { background: var(--primary); color: #fff; font-size: .88rem; }
.comparison td { color: #2a3a4a; font-size: .9rem; }
.faq-section { background: var(--bg); border-top: 1px solid var(--border); padding: 64px 24px; }
.faq-inner { margin: 0 auto; max-width: 760px; }
.faq-inner h2 { color: var(--primary); font-size: 1.7rem; margin-bottom: 24px; }
details { background: #fff; border: 1px solid var(--border); border-radius: 8px; margin-bottom: 10px; }
summary { color: var(--primary); cursor: pointer; font-weight: 800; padding: 16px 20px; }
.faq-a { color: #2a3a4a; line-height: 1.85; padding: 0 20px 18px; }
.related { background: var(--surface); padding: 64px 24px; }
.related-inner { margin: 0 auto; max-width: 980px; }
.related h2 { color: var(--primary); font-size: 1.6rem; margin-bottom: 24px; text-align: center; }
.related-grid { display: grid; gap: 14px; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); }
.related-card { border: 1px solid var(--border); border-radius: 10px; color: inherit; padding: 20px; text-decoration: none; }
.related-card:hover { border-color: var(--accent); }
.rc-label { color: var(--accent); font-size: .7rem; font-weight: 800; }
.rc-title { color: var(--primary); font-weight: 800; margin: 8px 0; }
.rc-desc { color: var(--muted); font-size: .84rem; line-height: 1.7; }
.cta-section { background: linear-gradient(135deg, var(--primary), #0d2240); padding: 64px 24px; text-align: center; }
.cta-section h2 { color: #fff; font-size: clamp(1.5rem, 3.5vw, 2.2rem); margin-bottom: 12px; }
.cta-section p { color: rgba(255, 255, 255, .65); margin: 0 auto 28px; max-width: 580px; }
.cta-buttons { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }
.btn-primary, .btn-outline { border-radius: 9px; font-weight: 700; padding: 13px 24px; text-decoration: none; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-outline { border: 1px solid rgba(255, 255, 255, .35); color: #fff; }
footer { background: #091726; padding: 36px 24px; }
.footer-inner { align-items: center; display: flex; flex-wrap: wrap; gap: 20px; justify-content: space-between; margin: 0 auto; max-width: 1080px; }
.footer-logo { align-items: center; color: #fff; display: flex; font-weight: 800; gap: 9px; text-decoration: none; }
.footer-logo-mark { border-radius: 6px; width: 24px; }
.footer-links { display: flex; flex-wrap: wrap; gap: 16px; }
.footer-links a { color: rgba(255, 255, 255, .58); font-size: .75rem; text-decoration: none; }
.footer-copy { color: rgba(255, 255, 255, .38); font-size: .72rem; }
@media (max-width: 640px) {
  nav { padding: 0 18px; }
  .nav-links { gap: 12px; }
  .nav-links li:not(:nth-last-child(-n+2)) { display: none; }
  .article-inner { padding: 48px 20px; }
  .hero { padding: 60px 20px 52px; }
  .footer-inner { align-items: flex-start; flex-direction: column; }
}