:root {
    --teal: #01C3D0;
    --teal-dark: #009faa;
    --teal-light: #e0f9fb;
    --teal-mid: #b2eff3;
    --green: #00E5A0;
    --navy: #0a1628;
    --dark: #111827;
    --muted: #6b7280;
    --light: #f8fffe;
    --border: #eef2f0;
    --white: #ffffff;
  }

  *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
  html { scroll-behavior: smooth; }

  body {
    font-family: 'DM Sans', sans-serif;
    background: var(--light);
    color: var(--dark);
    overflow-x: hidden;
  }

  /* ── NAV ── */
  nav {
    position: fixed; top: 0; left: 0; right: 0; z-index: 100;
    display: flex; align-items: center; justify-content: space-between;
    padding: 18px 6%;
    background: rgba(248,255,254,0.92);
    backdrop-filter: blur(16px);
    border-bottom: 1px solid rgba(1,195,208,.12);
    box-shadow: 0 2px 20px rgba(0,0,0,.04);
  }
  .nav-logo {
    font-family: 'Roboto', sans-serif; font-weight: 800; font-size: 1.4rem;
    color: var(--teal); letter-spacing: -.02em; text-decoration: none;
  }
  .nav-logo span { color: #FEBB1E; }
  .nav-back {
    display: inline-flex; align-items: center; gap: 8px;
    font-size: .88rem; font-weight: 500; color: var(--muted);
    text-decoration: none; transition: color .2s;
  }
  .nav-back:hover { color: var(--teal); }
  .nav-back svg { transition: transform .2s; }
  .nav-back:hover svg { transform: translateX(-3px); }
  .nav-cta {
    background: var(--teal); color: #fff; border: none; border-radius: 100px;
    padding: 9px 20px; font-family: 'DM Sans', sans-serif; font-size: .88rem;
    font-weight: 500; cursor: pointer; text-decoration: none;
    box-shadow: 0 4px 16px rgba(1,195,208,.3); transition: all .2s;
  }
  .nav-cta:hover { background: var(--teal-dark); transform: translateY(-1px); }

  /* ── HERO HEADER ── */
  .page-hero {
    background: linear-gradient(135deg, var(--navy) 0%, #0d2535 100%);
    padding: 140px 6% 80px;
    position: relative;
    overflow: hidden;
    text-align: center;
  }
  .page-hero::before {
    content: '';
    position: absolute; inset: 0;
    background:
      radial-gradient(ellipse at 15% 50%, rgba(1,195,208,.15) 0%, transparent 55%),
      radial-gradient(ellipse at 85% 30%, rgba(0,229,160,.08) 0%, transparent 50%);
  }
  .page-hero::after {
    content: '';
    position: absolute; bottom: 0; left: 0; right: 0;
    height: 60px;
    background: var(--light);
    clip-path: ellipse(55% 100% at 50% 100%);
  }

  .hero-icon {
    width: 72px; height: 72px;
    background: rgba(1,195,208,.15);
    border: 1.5px solid rgba(1,195,208,.25);
    border-radius: 22px;
    display: inline-flex; align-items: center; justify-content: center;
    font-size: 2rem; margin-bottom: 1.5rem;
    position: relative; z-index: 1;
    animation: fadeDown .6s ease both;
  }
  .page-title {
    font-family: 'Roboto', sans-serif;
    font-size: clamp(2rem, 4vw, 3rem);
    font-weight: 800; line-height: 1.1; letter-spacing: -.025em;
    color: #fff;
    position: relative; z-index: 1;
    animation: fadeDown .6s ease .1s both;
  }
  .page-subtitle {
    margin-top: .8rem;
    font-size: 1rem; color: rgba(255,255,255,.5);
    position: relative; z-index: 1;
    animation: fadeDown .6s ease .2s both;
  }
  .page-meta {
    display: inline-flex; align-items: center; gap: 8px;
    margin-top: 1.5rem;
    background: rgba(255,255,255,.08);
    border: 1px solid rgba(255,255,255,.12);
    border-radius: 100px;
    padding: 8px 18px;
    font-size: .8rem; color: rgba(255,255,255,.55);
    position: relative; z-index: 1;
    animation: fadeDown .6s ease .3s both;
  }
  .meta-dot { width: 6px; height: 6px; border-radius: 50%; background: var(--green); }

  /* ── LAYOUT ── */
  .content-wrapper {
    max-width: 1100px;
    margin: 0 auto;
    padding: 60px 6% 100px;
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 60px;
    align-items: start;
  }

  /* ── SIDEBAR TOC ── */
  .sidebar {
    position: sticky;
    top: 100px;
  }
  .toc-card {
    background: #fff;
    border: 1.5px solid var(--border);
    border-radius: 20px;
    padding: 24px;
    box-shadow: 0 4px 20px rgba(0,0,0,.04);
  }
  .toc-title {
    font-family: 'Roboto', sans-serif;
    font-size: .75rem; font-weight: 700;
    letter-spacing: .1em; text-transform: uppercase;
    color: var(--muted); margin-bottom: 1rem;
  }
  .toc-list { list-style: none; }
  .toc-list li { margin-bottom: 2px; }
  .toc-list a {
    display: block;
    font-size: .85rem; font-weight: 400;
    color: var(--muted);
    text-decoration: none;
    padding: 7px 12px;
    border-radius: 10px;
    transition: all .2s;
    border-left: 2px solid transparent;
  }
  .toc-list a:hover,
  .toc-list a.active { color: var(--teal); background: var(--teal-light); border-left-color: var(--teal); font-weight: 500; }

  .toc-divider { height: 1px; background: var(--border); margin: 16px 0; }

  .toc-contact {
    background: var(--teal-light);
    border: 1px solid var(--teal-mid);
    border-radius: 14px;
    padding: 16px;
    margin-top: 16px;
  }
  .toc-contact p { font-size: .8rem; color: var(--teal-dark); line-height: 1.5; }
  .toc-contact a { color: var(--teal-dark); font-weight: 600; text-decoration: none; }

  /* ── ARTICLE CONTENT ── */
  .article {
    min-width: 0;
  }

  .section-block {
    margin-bottom: 3rem;
    padding-bottom: 3rem;
    border-bottom: 1.5px solid var(--border);
    animation: fadeUp .5s ease both;
  }
  .section-block:last-child { border-bottom: none; margin-bottom: 0; }

  .section-num {
    display: inline-flex; align-items: center; gap: 10px;
    margin-bottom: 1rem;
  }
  .num-badge {
    width: 32px; height: 32px;
    background: var(--teal);
    color: #fff;
    border-radius: 10px;
    display: flex; align-items: center; justify-content: center;
    font-family: 'Roboto', sans-serif;
    font-size: .8rem; font-weight: 800;
    flex-shrink: 0;
  }
  .section-block h2 {
    font-family: 'Roboto', sans-serif;
    font-size: 1.35rem; font-weight: 800;
    color: var(--dark); line-height: 1.2;
    letter-spacing: -.01em;
  }
  .section-block h3 {
    font-family: 'Roboto', sans-serif;
    font-size: 1rem; font-weight: 700;
    color: var(--dark); margin: 1.5rem 0 .6rem;
  }
  .section-block p {
    font-size: .95rem; line-height: 1.8;
    color: #374151; margin-bottom: 1rem;
  }
  .section-block p:last-child { margin-bottom: 0; }

  .section-block ul, .section-block ol {
    margin: .8rem 0 1rem 0;
    padding-left: 0;
    list-style: none;
  }
  .section-block ul li, .section-block ol li {
    font-size: .95rem; line-height: 1.8; color: #374151;
    padding: 6px 0 6px 28px;
    position: relative;
    border-bottom: 1px solid #f3f4f6;
  }
  .section-block ul li:last-child, .section-block ol li:last-child { border-bottom: none; }
  .section-block ul li::before {
    content: '';
    position: absolute; left: 0; top: 14px;
    width: 8px; height: 8px; border-radius: 50%;
    background: var(--teal);
  }
  .section-block ol { counter-reset: ol-counter; }
  .section-block ol li { counter-increment: ol-counter; }
  .section-block ol li::before {
    content: counter(ol-counter);
    position: absolute; left: 0; top: 5px;
    width: 20px; height: 20px; border-radius: 6px;
    background: var(--teal-light); color: var(--teal-dark);
    font-size: .72rem; font-weight: 700;
    display: flex; align-items: center; justify-content: center;
    font-family: 'Roboto', sans-serif;
  }

  /* Highlight box */
  .highlight-box {
    background: var(--teal-light);
    border: 1.5px solid var(--teal-mid);
    border-left: 4px solid var(--teal);
    border-radius: 14px;
    padding: 18px 20px;
    margin: 1.2rem 0;
  }
  .highlight-box p { font-size: .9rem; color: var(--teal-dark); margin: 0; }
  .highlight-box strong { color: var(--teal-dark); }

  .warning-box {
    background: #fff8e6;
    border: 1.5px solid #fde68a;
    border-left: 4px solid #f59e0b;
    border-radius: 14px;
    padding: 18px 20px;
    margin: 1.2rem 0;
  }
  .warning-box p { font-size: .9rem; color: #92400e; margin: 0; }

  /* Data table */
  .data-table {
    width: 100%; border-collapse: collapse;
    margin: 1.2rem 0; font-size: .88rem;
    border-radius: 14px; overflow: hidden;
    border: 1.5px solid var(--border);
  }
  .data-table th {
    background: var(--navy); color: #fff;
    padding: 12px 16px; text-align: left;
    font-family: 'Roboto', sans-serif; font-size: .78rem;
    font-weight: 700; letter-spacing: .05em; text-transform: uppercase;
  }
  .data-table td { padding: 12px 16px; border-bottom: 1px solid var(--border); color: #374151; line-height: 1.5; }
  .data-table tr:last-child td { border-bottom: none; }
  .data-table tr:nth-child(even) td { background: #f9fffe; }

  /* Tag chips */
  .chip {
    display: inline-block;
    background: var(--teal-light); color: var(--teal-dark);
    border: 1px solid var(--teal-mid);
    border-radius: 100px; padding: 3px 12px;
    font-size: .75rem; font-weight: 600;
    margin: 2px;
  }

  /* ── FOOTER ── */
  footer {
    background: var(--navy);
    color: rgba(255,255,255,.5);
    padding: 50px 6% 30px;
  }
  .footer-inner {
    max-width: 1100px; margin: 0 auto;
    display: flex; justify-content: space-between; align-items: center;
    flex-wrap: wrap; gap: 1rem;
    padding-bottom: 1.5rem;
    border-bottom: 1px solid rgba(255,255,255,.08);
  }
  .footer-logo { font-family: 'Roboto', sans-serif; font-weight: 800; font-size: 1.2rem; color: var(--teal); text-decoration: none; }
  .footer-logo span { color:rgb(254,187,30); }
  .footer-links-row { display: flex; gap: 1.5rem; flex-wrap: wrap; }
  .footer-links-row a { font-size: .82rem; color: rgba(255,255,255,.4); text-decoration: none; transition: color .2s; }
  .footer-links-row a:hover { color: var(--teal); }
  .footer-links-row a.current { color: var(--teal); font-weight: 600; }
  .footer-copy { max-width: 1100px; margin: 1.5rem auto 0; font-size: .78rem; text-align: center; }

  /* ── ANIMATIONS ── */
  @keyframes fadeDown { from { opacity: 0; transform: translateY(-16px); } to { opacity: 1; transform: translateY(0); } }
  @keyframes fadeUp { from { opacity: 0; transform: translateY(16px); } to { opacity: 1; transform: translateY(0); } }

  /* ── RESPONSIVE ── */
  @media (max-width: 900px) {
    .content-wrapper { grid-template-columns: 1fr; gap: 32px; }
    .sidebar { position: static; }
  }
  @media (max-width: 600px) {
    nav { padding: 14px 5%; }
    .nav-links-row { display: none; }
    .page-hero { padding: 120px 5% 70px; }
    .content-wrapper { padding: 40px 5% 60px; }
  }