*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
:root {
  --navy: #0F294D; --navy-dark: #050E24; --ink: #16233A; --gold: #D9A820;
  --white: #FFFFFF; --gray: #F0F3F8; --text: #10182B; --muted: #6B7280; --radius: 16px;
}
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: var(--text); background: var(--white); line-height: 1.7;
}

/* NAV */
body > nav {
  position: sticky; top: 0; z-index: 100;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 5vw; height: 64px;
  background: rgba(255,255,255,0.92); backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0,0,0,0.06);
}
.nav-logo { display: flex; align-items: center; gap: 10px; font-size: 1.25rem; font-weight: 800; color: var(--navy-dark); text-decoration: none; white-space: nowrap; }
.nav-logo img { width: 32px; height: 32px; border-radius: 8px; }
.logo-text span { color: var(--navy); }
.nav-links { display: flex; align-items: center; gap: 28px; list-style: none; }
.nav-links a { font-size: 0.9rem; font-weight: 500; color: var(--muted); text-decoration: none; transition: color .2s; }
.nav-links a:hover { color: var(--navy); }
.nav-cta { background: var(--navy); color: #fff !important; padding: 8px 18px; border-radius: 20px; }
.nav-cta:hover { background: var(--navy-dark) !important; }

/* HEADER */
.article-header {
  position: relative; overflow: hidden;
  background: linear-gradient(135deg, var(--navy-dark) 0%, var(--navy) 55%, var(--ink) 100%);
  color: var(--white); padding: 56px 5vw 52px;
}
.article-header-inner { max-width: 760px; margin: 0 auto; }
.breadcrumb { font-size: 0.82rem; color: rgba(255,255,255,0.6); margin-bottom: 18px; }
.breadcrumb a { color: rgba(255,255,255,0.8); text-decoration: none; }
.breadcrumb a:hover { color: #fff; }
.article-header h1 { font-size: clamp(1.9rem, 4.5vw, 2.8rem); font-weight: 900; letter-spacing: -0.02em; line-height: 1.15; margin-bottom: 16px; }
.article-meta { display: flex; flex-wrap: wrap; gap: 10px; align-items: center; font-size: 0.82rem; color: rgba(255,255,255,0.7); }
.tag { display: inline-block; background: var(--gold); color: var(--navy-dark); font-weight: 700; font-size: 0.72rem; letter-spacing: 0.05em; text-transform: uppercase; padding: 3px 10px; border-radius: 20px; }
.accent-bar { position: absolute; bottom: 0; left: 0; right: 0; height: 6px; background: linear-gradient(to right, var(--navy) 0%, var(--gold) 50%, var(--navy) 100%); }

/* ARTICLE BODY */
.article { max-width: 760px; margin: 0 auto; padding: 48px 5vw 24px; }
.article .lead { font-size: 1.12rem; color: var(--ink); margin-bottom: 28px; }
.article h2 { font-size: 1.5rem; font-weight: 800; letter-spacing: -0.01em; color: var(--navy-dark); margin: 40px 0 14px; }
.article h3 { font-size: 1.15rem; font-weight: 700; color: var(--navy); margin: 26px 0 10px; }
.article p { margin-bottom: 16px; }
.article ul, .article ol { margin: 0 0 18px 24px; }
.article li { margin-bottom: 6px; }
.article a { color: var(--navy); font-weight: 600; text-decoration: underline; text-decoration-color: rgba(217,168,32,0.7); text-underline-offset: 3px; }
.article a:hover { text-decoration-color: var(--navy); }
.article table { width: 100%; border-collapse: collapse; margin: 8px 0 22px; font-size: 0.93rem; }
.article th, .article td { border: 1px solid #E2E7EF; padding: 10px 12px; text-align: left; vertical-align: top; }
.article th { background: var(--gray); font-weight: 700; color: var(--navy-dark); }
.table-wrap { overflow-x: auto; }

.toc { background: var(--gray); border-radius: var(--radius); padding: 20px 24px; margin: 0 0 32px; }
.toc strong { display: block; font-size: 0.8rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--navy); margin-bottom: 8px; }
.toc ol { margin: 0 0 0 20px; }
.toc a { font-weight: 500; text-decoration: none; }

.key-box { border-left: 5px solid var(--gold); background: #FFFBEB; border-radius: 0 var(--radius) var(--radius) 0; padding: 18px 22px; margin: 24px 0; }
.key-box strong:first-child { display: block; color: var(--navy-dark); margin-bottom: 6px; }
.key-box ul { margin-bottom: 0; }
.example-box { background: var(--gray); border-radius: var(--radius); padding: 18px 22px; margin: 24px 0; }
.example-box p:last-child { margin-bottom: 0; }

.faq h3 { margin-top: 20px; }

.cta-box {
  margin: 44px 0 16px; padding: 30px 28px; border-radius: var(--radius); text-align: center;
  background: linear-gradient(135deg, var(--navy-dark), var(--navy)); color: #fff;
}
.cta-box h2 { color: #fff; margin: 0 0 8px; font-size: 1.35rem; }
.cta-box p { color: rgba(255,255,255,0.75); margin-bottom: 20px; }
.article .cta-box a.btn-primary {
  display: inline-block; background: var(--gold); color: var(--navy-dark);
  padding: 13px 24px; border-radius: 14px; font-weight: 700; text-decoration: none;
  transition: transform .2s;
}
.article .cta-box a.btn-primary:hover { transform: translateY(-2px); }

.related { max-width: 760px; margin: 0 auto; padding: 8px 5vw 64px; }
.related h2 { font-size: 1.2rem; font-weight: 800; margin-bottom: 14px; color: var(--navy-dark); }
.related ul { list-style: none; display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 12px; }
.related a { display: block; height: 100%; background: var(--gray); border-radius: 12px; padding: 14px 16px; color: var(--navy-dark); font-weight: 600; text-decoration: none; transition: background .2s; }
.related a:hover { background: #E3E9F3; }

/* INDEX */
.index-section { max-width: 1100px; margin: 0 auto; padding: 48px 5vw 24px; }
.index-section h2 { font-size: 1.5rem; font-weight: 800; color: var(--navy-dark); margin-bottom: 6px; }
.index-section > p { color: var(--muted); margin-bottom: 22px; }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 18px; }
.card { display: block; background: var(--white); border: 1px solid #E8ECF3; border-radius: var(--radius); padding: 22px; text-decoration: none; color: var(--text); box-shadow: 0 2px 10px rgba(0,0,0,0.04); transition: transform .2s, box-shadow .2s; }
.card:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(0,0,0,0.09); }
.card .tag { margin-bottom: 10px; }
.card h3 { font-size: 1.02rem; font-weight: 700; color: var(--navy-dark); margin-bottom: 6px; line-height: 1.35; }
.card p { font-size: 0.88rem; color: var(--muted); line-height: 1.55; }

/* FOOTER */
footer { background: var(--text); color: rgba(255,255,255,0.5); padding: 36px 5vw; text-align: center; font-size: 0.85rem; }
footer a { color: rgba(255,255,255,0.65); text-decoration: none; }
footer a:hover { color: #fff; }
.footer-links { display: flex; gap: 24px; justify-content: center; flex-wrap: wrap; margin-bottom: 16px; }
.footer-credit { margin-top: 10px; font-size: 0.8rem; color: rgba(255,255,255,0.4); }
.footer-credit a { color: rgba(255,255,255,0.55); font-weight: 600; }

@media (max-width: 600px) {
  .nav-links { display: none; }
  .article { padding-top: 36px; }
}