:root {
      --navy-950: #071321;
      --navy-900: #0b1d31;
      --navy-800: #12304d;
      --blue-700: #195f90;
      --blue-600: #1478ad;
      --cyan-500: #22b6c7;
      --cyan-300: #76dfe8;
      --mint-400: #62d6b4;
      --lime-400: #b6e66a;
      --paper: #f5f8fb;
      --white: #ffffff;
      --ink: #12263a;
      --muted: #587085;
      --line: #dbe6ee;
      --soft-blue: #eaf6fb;
      --soft-mint: #eaf9f4;
      --soft-lime: #f3f9e7;
      --shadow: 0 18px 50px rgba(8, 39, 65, 0.12);
      --shadow-soft: 0 10px 30px rgba(8, 39, 65, 0.08);
      --radius-xl: 28px;
      --radius-lg: 20px;
      --radius-md: 14px;
      --content: 1180px;
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
      color: var(--ink);
      background: var(--paper);
      line-height: 1.55;
    }

    a { color: inherit; text-decoration: none; }
    button, input { font: inherit; }
    img, svg { display: block; max-width: 100%; }
    .container { width: min(calc(100% - 40px), var(--content)); margin: 0 auto; }

    .topbar {
      background: var(--navy-950);
      color: #d7e5ee;
      font-size: 0.86rem;
    }
    .topbar .container {
      min-height: 38px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 20px;
    }
    .topbar strong { color: var(--cyan-300); }
    .topbar-links { display: flex; gap: 20px; white-space: nowrap; }

    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(255,255,255,0.95);
      backdrop-filter: blur(12px);
      border-bottom: 1px solid rgba(219,230,238,.85);
    }
    .header-inner {
      min-height: 78px;
      display: grid;
      grid-template-columns: auto 1fr auto;
      align-items: center;
      gap: 28px;
    }
    .brand {
      display: inline-flex;
      align-items: center;
      line-height: 0;
    }
    .brand-logo {
      height: 48px;
      width: auto;
      max-width: 168px;
    }
    .brand-icon {
      display: none;
      width: 40px;
      height: 40px;
      object-fit: contain;
    }
    .brand--footer {
      display: inline-block;
      background: transparent;
      padding: 0;
    }
    .brand--footer .brand-logo {
      height: 52px;
      max-width: 180px;
    }

    .main-nav {
      display: flex;
      justify-content: center;
      align-items: center;
      gap: 22px;
      font-size: .92rem;
      font-weight: 680;
      color: #29475d;
    }
    .main-nav a { position: relative; padding: 28px 0; }
    .main-nav a::after {
      content: "";
      position: absolute;
      left: 0; right: 0; bottom: 18px;
      height: 2px;
      background: var(--cyan-500);
      transform: scaleX(0);
      transition: transform .2s ease;
    }
    .main-nav a:hover::after { transform: scaleX(1); }

    .header-actions { display: flex; gap: 10px; align-items: center; }
    .btn {
      border: 0;
      border-radius: 999px;
      padding: 12px 18px;
      font-weight: 760;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      cursor: pointer;
      transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
    }
    .btn:hover { transform: translateY(-2px); }
    .btn-primary {
      color: var(--white);
      background: linear-gradient(135deg, var(--blue-600), var(--cyan-500));
      box-shadow: 0 10px 24px rgba(20,120,173,.24);
    }
    .btn-secondary {
      color: var(--navy-900);
      background: var(--white);
      border: 1px solid var(--line);
    }
    .btn-ghost { color: var(--blue-700); background: transparent; padding-inline: 8px; }
    .mobile-toggle {
      display: none;
      width: 42px;
      height: 42px;
      border-radius: 12px;
      border: 1px solid var(--line);
      background: var(--white);
      cursor: pointer;
    }

    .hero {
      position: relative;
      overflow: hidden;
      background:
        radial-gradient(circle at 78% 22%, rgba(34,182,199,.24), transparent 27%),
        radial-gradient(circle at 8% 88%, rgba(98,214,180,.18), transparent 30%),
        linear-gradient(135deg, var(--navy-950), var(--navy-800));
      color: var(--white);
      padding: 82px 0 70px;
    }
    .hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image:
        linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
      background-size: 34px 34px;
      mask-image: linear-gradient(to bottom, black, transparent 85%);
    }
    .hero-grid {
      position: relative;
      display: grid;
      grid-template-columns: 1.12fr .88fr;
      gap: 56px;
      align-items: center;
    }
    .eyebrow {
      display: inline-flex;
      align-items: center;
      gap: 9px;
      padding: 7px 12px;
      border-radius: 999px;
      background: rgba(118,223,232,.12);
      border: 1px solid rgba(118,223,232,.25);
      color: #baf3f6;
      font-weight: 760;
      font-size: .82rem;
      letter-spacing: .02em;
      text-transform: uppercase;
    }
    .eyebrow-dot {
      width: 8px; height: 8px; border-radius: 50%;
      background: var(--lime-400);
      box-shadow: 0 0 0 5px rgba(182,230,106,.12);
    }
    h1 {
      margin: 20px 0 20px;
      font-size: clamp(3rem, 6vw, 5.6rem);
      line-height: .98;
      letter-spacing: -.058em;
      max-width: 800px;
    }
    .hero-highlight {
      background: linear-gradient(90deg, var(--cyan-300), var(--lime-400));
      -webkit-background-clip: text;
      background-clip: text;
      color: transparent;
    }
    .hero-copy {
      max-width: 680px;
      color: #c7d8e4;
      font-size: 1.15rem;
      margin: 0 0 28px;
    }
    .hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 30px; }
    .hero .btn-secondary { background: rgba(255,255,255,.08); color: white; border-color: rgba(255,255,255,.18); }
    .trust-line {
      display: flex;
      flex-wrap: wrap;
      gap: 18px;
      color: #9fb8c8;
      font-size: .88rem;
    }
    .trust-line span { display: inline-flex; gap: 7px; align-items: center; }
    .trust-line svg { width: 16px; height: 16px; color: var(--mint-400); }

    .qa-panel {
      position: relative;
      border-radius: var(--radius-xl);
      padding: 24px;
      background: rgba(255,255,255,.09);
      border: 1px solid rgba(255,255,255,.16);
      box-shadow: 0 34px 70px rgba(0,0,0,.28);
      backdrop-filter: blur(14px);
    }
    .qa-panel::after {
      content: "";
      position: absolute;
      width: 120px; height: 120px;
      border-radius: 50%;
      right: -35px; top: -42px;
      background: rgba(182,230,106,.16);
      filter: blur(2px);
    }
    .panel-label { color: #a8c6d6; font-size: .82rem; font-weight: 730; text-transform: uppercase; letter-spacing: .08em; }
    .qa-panel h2 { font-size: 1.65rem; line-height: 1.2; margin: 8px 0 18px; }
    .ask-box {
      background: var(--white);
      border-radius: 18px;
      padding: 8px;
      display: grid;
      grid-template-columns: 1fr auto;
      gap: 8px;
      box-shadow: 0 10px 24px rgba(0,0,0,.18);
    }
    .ask-box input {
      border: 0;
      outline: none;
      padding: 12px 14px;
      min-width: 0;
      color: var(--ink);
      background: transparent;
    }
    .ask-box .btn { border-radius: 13px; padding-inline: 15px; }
    .popular-questions { display: grid; gap: 9px; margin-top: 18px; }
    .question-chip {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 14px;
      padding: 12px 14px;
      border-radius: 13px;
      color: #d8e7ef;
      background: rgba(255,255,255,.07);
      border: 1px solid rgba(255,255,255,.1);
      font-size: .9rem;
    }
    .question-chip:hover { background: rgba(255,255,255,.12); }
    .question-chip span:last-child { color: var(--cyan-300); }

    .stats-wrap { margin-top: -32px; position: relative; z-index: 3; }
    .stats {
      background: var(--white);
      border-radius: 20px;
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      box-shadow: var(--shadow);
      border: 1px solid var(--line);
      overflow: hidden;
    }
    .stat { padding: 24px 26px; border-right: 1px solid var(--line); }
    .stat:last-child { border-right: 0; }
    .stat strong { display: block; font-size: 1.45rem; color: var(--navy-900); letter-spacing: -.03em; }
    .stat span { color: var(--muted); font-size: .88rem; }

    .section { padding: 88px 0; }
    .section-sm { padding: 64px 0; }
    .section-white { background: var(--white); }
    .section-dark {
      background: linear-gradient(145deg, var(--navy-950), var(--navy-800));
      color: var(--white);
    }
    .section-head {
      display: flex;
      justify-content: space-between;
      align-items: end;
      gap: 28px;
      margin-bottom: 36px;
    }
    .kicker {
      color: var(--blue-600);
      font-weight: 820;
      font-size: .82rem;
      text-transform: uppercase;
      letter-spacing: .09em;
    }
    .section-dark .kicker { color: var(--cyan-300); }
    h2.section-title {
      margin: 7px 0 0;
      font-size: clamp(2rem, 4vw, 3.25rem);
      letter-spacing: -.045em;
      line-height: 1.08;
    }
    .section-intro {
      max-width: 520px;
      color: var(--muted);
      margin: 0;
    }
    .section-dark .section-intro { color: #b4c9d7; }

    .pillar-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 18px;
    }
    .pillar-card {
      min-height: 330px;
      border-radius: var(--radius-lg);
      padding: 24px;
      border: 1px solid var(--line);
      background: var(--white);
      box-shadow: var(--shadow-soft);
      display: flex;
      flex-direction: column;
      transition: transform .22s ease, box-shadow .22s ease;
    }
    .pillar-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }
    .pillar-icon {
      width: 52px; height: 52px;
      border-radius: 16px;
      display: grid; place-items: center;
      margin-bottom: 24px;
    }
    .pillar-icon svg { width: 27px; height: 27px; }
    .icon-blue { color: var(--blue-700); background: var(--soft-blue); }
    .icon-mint { color: #168f72; background: var(--soft-mint); }
    .icon-lime { color: #547e18; background: var(--soft-lime); }
    .icon-navy { color: var(--navy-800); background: #edf1f5; }
    .pillar-card h3 { margin: 0 0 10px; font-size: 1.25rem; letter-spacing: -.02em; }
    .pillar-card p { color: var(--muted); margin: 0 0 22px; font-size: .95rem; }
    .pillar-card a { margin-top: auto; color: var(--blue-600); font-weight: 760; display: inline-flex; align-items: center; gap: 7px; }

    .topic-layout {
      display: grid;
      grid-template-columns: 1.15fr .85fr;
      gap: 24px;
    }
    .topic-main {
      border-radius: var(--radius-xl);
      background:
        radial-gradient(circle at 88% 15%, rgba(34,182,199,.16), transparent 35%),
        var(--navy-900);
      color: white;
      padding: 34px;
      min-height: 430px;
      display: grid;
      align-content: space-between;
      overflow: hidden;
      position: relative;
    }
    .topic-main h3 { font-size: 2.3rem; line-height: 1.08; letter-spacing: -.04em; margin: 10px 0 14px; max-width: 580px; }
    .topic-main p { color: #bdd0dc; max-width: 580px; }
    .topic-tags { display: flex; flex-wrap: wrap; gap: 9px; margin-top: 24px; }
    .topic-tags span { background: rgba(255,255,255,.08); border: 1px solid rgba(255,255,255,.12); padding: 8px 11px; border-radius: 999px; font-size: .82rem; color: #d7e7ef; }
    .topic-visual {
      justify-self: end;
      width: 84%;
      max-width: 490px;
      background: white;
      color: var(--ink);
      border-radius: 18px 18px 0 0;
      padding: 18px;
      margin: 26px -18px -34px 0;
      transform: rotate(-2deg);
      box-shadow: 0 24px 48px rgba(0,0,0,.24);
    }
    .mini-bar { height: 9px; border-radius: 999px; background: #dce8ef; margin-bottom: 12px; overflow: hidden; }
    .mini-bar span { display: block; height: 100%; border-radius: inherit; background: linear-gradient(90deg, var(--blue-600), var(--cyan-500)); }
    .mini-list { display: grid; gap: 10px; margin-top: 14px; }
    .mini-row { display: grid; grid-template-columns: 32px 1fr auto; gap: 10px; align-items: center; font-size: .77rem; color: #547085; }
    .mini-check { width: 28px; height: 28px; border-radius: 8px; background: var(--soft-mint); color: #168f72; display: grid; place-items: center; font-weight: 900; }

    .topic-side { display: grid; gap: 18px; }
    .side-card {
      padding: 24px;
      border-radius: var(--radius-lg);
      background: var(--white);
      border: 1px solid var(--line);
      box-shadow: var(--shadow-soft);
    }
    .side-card h3 { margin: 13px 0 8px; font-size: 1.22rem; }
    .side-card p { margin: 0 0 18px; color: var(--muted); font-size: .92rem; }
    .side-card .small-link { color: var(--blue-600); font-weight: 760; font-size: .9rem; }

    .learning-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
    .learning-card {
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-soft);
    }
    .learning-top {
      min-height: 120px;
      padding: 24px;
      display: flex;
      justify-content: space-between;
      align-items: start;
      background: linear-gradient(135deg, var(--soft-blue), #f8fcfe);
    }
    .learning-card:nth-child(2) .learning-top { background: linear-gradient(135deg, var(--soft-mint), #f9fdfb); }
    .learning-card:nth-child(3) .learning-top { background: linear-gradient(135deg, var(--soft-lime), #fcfef7); }
    .level {
      padding: 6px 9px;
      border-radius: 999px;
      background: rgba(255,255,255,.78);
      font-size: .72rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: .06em;
      color: var(--blue-700);
    }
    .learning-top svg { width: 54px; height: 54px; color: var(--blue-600); }
    .learning-body { padding: 24px; }
    .learning-body h3 { margin: 0 0 8px; font-size: 1.3rem; }
    .learning-body p { margin: 0 0 20px; color: var(--muted); }
    .lesson-list { list-style: none; padding: 0; margin: 0 0 20px; display: grid; gap: 10px; color: #3d5b70; font-size: .9rem; }
    .lesson-list li { display: flex; gap: 9px; align-items: start; }
    .lesson-list li::before { content: "✓"; color: #168f72; font-weight: 900; }

    .resource-grid {
      display: grid;
      grid-template-columns: 1.15fr .85fr;
      gap: 22px;
      align-items: stretch;
    }
    .resource-feature {
      padding: 34px;
      border-radius: var(--radius-xl);
      background: linear-gradient(135deg, #eef8fc, #f8fcfd);
      border: 1px solid #d2e9f1;
      display: grid;
      grid-template-columns: 1fr .72fr;
      gap: 28px;
      align-items: center;
    }
    .resource-feature h3 { margin: 8px 0 12px; font-size: 2rem; line-height: 1.12; letter-spacing: -.035em; }
    .resource-feature p { color: var(--muted); }
    .doc-stack { position: relative; min-height: 250px; }
    .doc {
      position: absolute;
      width: 78%;
      aspect-ratio: .76;
      right: 6%;
      top: 0;
      border-radius: 12px;
      background: white;
      border: 1px solid var(--line);
      box-shadow: 0 16px 35px rgba(20,72,100,.14);
      padding: 18px;
    }
    .doc:nth-child(1) { transform: rotate(-8deg); right: 18%; top: 20px; }
    .doc:nth-child(2) { transform: rotate(4deg); right: 2%; top: 12px; }
    .doc:nth-child(3) { transform: rotate(-1deg); }
    .doc-line { height: 8px; background: #dfe9ef; border-radius: 8px; margin: 10px 0; }
    .doc-line.short { width: 55%; }
    .doc-line.accent { background: var(--cyan-500); width: 36%; height: 10px; }
    .resource-list { display: grid; gap: 12px; }
    .resource-item {
      display: grid;
      grid-template-columns: 46px 1fr auto;
      gap: 14px;
      align-items: center;
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: 16px;
      padding: 15px;
    }
    .resource-item:hover { box-shadow: var(--shadow-soft); }
    .resource-item .ri-icon { width: 46px; height: 46px; border-radius: 13px; display: grid; place-items: center; background: var(--soft-mint); color: #168f72; }
    .resource-item h4 { margin: 0; font-size: .97rem; }
    .resource-item small { color: var(--muted); }
    .resource-item .arrow { color: var(--blue-600); font-size: 1.3rem; }

    .ask-section {
      display: grid;
      grid-template-columns: .85fr 1.15fr;
      gap: 36px;
      align-items: center;
    }
    .ask-copy h2 { margin: 10px 0 16px; font-size: 2.7rem; line-height: 1.08; letter-spacing: -.04em; }
    .ask-copy p { color: #b9ccd8; }
    .qa-thread {
      background: rgba(255,255,255,.08);
      border: 1px solid rgba(255,255,255,.13);
      border-radius: var(--radius-xl);
      padding: 24px;
    }
    .thread-q, .thread-a { border-radius: 16px; padding: 18px; }
    .thread-q { background: white; color: var(--ink); margin-bottom: 12px; }
    .thread-a { background: rgba(34,182,199,.13); color: #d9edf2; border: 1px solid rgba(118,223,232,.17); }
    .thread-meta { font-size: .74rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em; color: var(--blue-600); margin-bottom: 6px; }
    .thread-a .thread-meta { color: var(--cyan-300); }
    .thread-q p, .thread-a p { margin: 0; }

    .solution-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
    .solution-card {
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      background: var(--white);
      padding: 26px;
      display: flex;
      flex-direction: column;
      min-height: 280px;
    }
    .solution-card .number { font-size: .78rem; font-weight: 850; color: var(--cyan-500); }
    .solution-card h3 { font-size: 1.28rem; margin: 14px 0 10px; }
    .solution-card p { color: var(--muted); margin: 0 0 20px; }
    .solution-card a { color: var(--blue-600); font-weight: 760; margin-top: auto; }

    .newsletter {
      margin-bottom: 80px;
      background:
        radial-gradient(circle at 90% 10%, rgba(182,230,106,.2), transparent 30%),
        linear-gradient(135deg, var(--blue-700), var(--navy-900));
      border-radius: var(--radius-xl);
      padding: 44px;
      color: white;
      display: grid;
      grid-template-columns: 1fr .78fr;
      gap: 30px;
      align-items: center;
      box-shadow: var(--shadow);
    }
    .newsletter h2 { margin: 7px 0 10px; font-size: 2.2rem; line-height: 1.1; letter-spacing: -.04em; }
    .newsletter p { color: #c5d9e5; margin: 0; }
    .newsletter-form { display: grid; grid-template-columns: 1fr auto; background: white; padding: 7px; border-radius: 16px; }
    .newsletter-form input { border: 0; outline: 0; padding: 12px 14px; min-width: 0; }
    .newsletter-form .btn { border-radius: 11px; }

    footer { background: var(--navy-950); color: #afc3d1; padding: 54px 0 24px; }
    .footer-grid { display: grid; grid-template-columns: 1.5fr repeat(4, 1fr); gap: 30px; }
    .footer-brand p { max-width: 320px; font-size: .9rem; }
    .footer-col h4 { color: white; margin: 4px 0 14px; font-size: .94rem; }
    .footer-col a { display: block; padding: 5px 0; font-size: .87rem; }
    .footer-col a:hover { color: var(--cyan-300); }
    .footer-bottom { border-top: 1px solid rgba(255,255,255,.09); margin-top: 34px; padding-top: 20px; display: flex; justify-content: space-between; gap: 20px; font-size: .8rem; }

    @media (max-width: 1080px) {
      .main-nav { display: none; }
      .mobile-toggle { display: grid; place-items: center; }
      .header-inner { grid-template-columns: auto 1fr auto; }
      .header-actions .btn-secondary { display: none; }
      .header-actions { justify-self: end; }
      .pillar-grid { grid-template-columns: repeat(2, 1fr); }
      .footer-grid { grid-template-columns: 1.3fr repeat(2, 1fr); }
    }

    @media (max-width: 820px) {
      .topbar-links { display: none; }
      .hero { padding-top: 60px; }
      .hero-grid, .topic-layout, .resource-grid, .ask-section, .newsletter { grid-template-columns: 1fr; }
      .qa-panel { max-width: 620px; }
      .stats { grid-template-columns: repeat(2, 1fr); }
      .stat:nth-child(2) { border-right: 0; }
      .stat:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
      .learning-grid, .solution-grid { grid-template-columns: 1fr; }
      .resource-feature { grid-template-columns: 1fr; }
      .doc-stack { min-height: 310px; }
      .newsletter { padding: 34px; }
      .footer-grid { grid-template-columns: 1fr 1fr; }
      .footer-brand { grid-column: 1 / -1; }
    }

    @media (max-width: 560px) {
      .container { width: min(calc(100% - 26px), var(--content)); }
      .topbar { display: none; }
      .header-inner { min-height: 68px; gap: 12px; }
      .site-header .brand-logo { display: none; }
      .site-header .brand-icon { display: block; }
      .header-actions .btn-primary { display: none; }
      .hero { padding: 50px 0 58px; }
      h1 { font-size: 3.05rem; }
      .hero-copy { font-size: 1rem; }
      .ask-box { grid-template-columns: 1fr; }
      .ask-box .btn { width: 100%; }
      .stats-wrap { margin-top: -20px; }
      .stats { grid-template-columns: 1fr; }
      .stat { border-right: 0; border-bottom: 1px solid var(--line); }
      .stat:last-child { border-bottom: 0; }
      .section { padding: 66px 0; }
      .section-head { align-items: start; flex-direction: column; }
      .pillar-grid { grid-template-columns: 1fr; }
      .pillar-card { min-height: auto; }
      .topic-main { padding: 25px; }
      .topic-main h3 { font-size: 1.8rem; }
      .topic-visual { width: 100%; margin-right: -8px; }
      .resource-feature { padding: 25px; }
      .newsletter { padding: 26px; }
      .newsletter-form { grid-template-columns: 1fr; gap: 7px; background: transparent; padding: 0; }
      .newsletter-form input { background: white; border-radius: 11px; }
      .footer-grid { grid-template-columns: 1fr; }
      .footer-brand { grid-column: auto; }
      .footer-bottom { flex-direction: column; }
    }

    .mobile-menu {
      display: none;
      background: white;
      border-top: 1px solid var(--line);
      padding: 10px 20px 18px;
    }
    .mobile-menu.open { display: grid; }
    .mobile-menu a { padding: 11px 0; font-weight: 700; color: #29475d; border-bottom: 1px solid #eef3f6; }
    /* Extra: 8-item nav + shared PHP pages */
    .main-nav { gap: 13px; font-size: .82rem; }
    .main-nav a.is-active::after { transform: scaleX(1); }
    .page-hero {
      background:
        radial-gradient(circle at 78% 22%, rgba(34,182,199,.24), transparent 27%),
        linear-gradient(135deg, var(--navy-950), var(--navy-800));
      color: var(--white);
      padding: 72px 0 56px;
    }
    .page-hero h1 {
      margin: 16px 0 16px;
      font-size: clamp(2.2rem, 5vw, 3.6rem);
      line-height: 1.05;
      letter-spacing: -.045em;
      max-width: 820px;
    }
    .page-hero p { max-width: 68ch; color: #c7d8e4; font-size: 1.08rem; margin: 0; }
    .page-topics { padding: 64px 0 88px; }
    @media (max-width: 1200px) {
      .main-nav { display: none; }
      .mobile-toggle { display: grid; place-items: center; }
    }

    .learn-hero {
      position: relative;
      overflow: hidden;
      background:
        radial-gradient(circle at 78% 22%, rgba(34,182,199,.24), transparent 27%),
        linear-gradient(135deg, var(--navy-950), var(--navy-800));
      color: var(--white);
      padding: 56px 0 48px;
    }
    .learn-hero::before {
      content: "";
      position: absolute;
      inset: 0;
      background-image:
        linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
      background-size: 34px 34px;
      mask-image: linear-gradient(to bottom, black, transparent 85%);
    }
    .learn-hero .container,
    .learn-hero .hero-grid { position: relative; }
    .learn-hero h1 {
      margin: 12px 0 16px;
      font-size: clamp(2.2rem, 5vw, 3.6rem);
      line-height: 1.05;
      letter-spacing: -.045em;
      max-width: 860px;
    }
    .learn-hero .lead,
    .hero .lead {
      max-width: 720px;
      color: #c7d8e4;
      font-size: 1.12rem;
      margin: 0;
    }
    .learn-hero .kicker { color: var(--cyan-300); }
    .reading-card {
      background: rgba(255,255,255,.09);
      border: 1px solid rgba(255,255,255,.16);
      border-radius: var(--radius-lg);
      padding: 22px 24px;
      color: #d8e7ef;
      align-self: center;
    }
    .reading-card b { display: block; color: var(--white); font-size: 1.2rem; margin-bottom: 8px; }
    .breadcrumbs {
      padding: 16px 0 0;
      font-size: .88rem;
      color: var(--muted);
    }
    .breadcrumbs a { color: var(--blue-600); font-weight: 700; }
    .page { padding: 36px 0 72px; }
    .layout {
      display: grid;
      grid-template-columns: 260px 1fr;
      gap: 36px;
      align-items: start;
    }
    .sidebar { position: sticky; top: 110px; display: grid; gap: 16px; }
    .sidebox {
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: var(--radius-md);
      padding: 16px 16px 10px;
      box-shadow: var(--shadow-soft);
    }
    .sidebox h3 { margin: 0 0 10px; font-size: .92rem; letter-spacing: -.01em; }
    .sidebox a {
      display: block;
      padding: 7px 0;
      font-size: .86rem;
      color: #29475d;
      border-bottom: 1px solid #eef3f6;
    }
    .sidebox a:last-child { border-bottom: 0; }
    .sidebox a.active,
    .sidebox a:hover { color: var(--blue-600); font-weight: 760; }
    .article h2 { font-size: 1.55rem; letter-spacing: -.03em; margin: 0 0 12px; }
    .article section + section { margin-top: 34px; }
    .article p { color: #345066; }
    .article ul { color: #345066; padding-left: 1.2rem; }
    .article li + li { margin-top: 6px; }
    .article table { width: 100%; border-collapse: collapse; margin: 8px 0 6px; }
    .article th,
    .article td { border: 1px solid var(--line); padding: 10px 12px; text-align: left; vertical-align: top; }
    .article th { background: var(--soft-blue); color: var(--ink); font-size: .9rem; }
    .callout,
    .warning,
    .tip {
      border-radius: 14px;
      padding: 14px 16px;
      margin: 16px 0;
    }
    .callout { background: var(--soft-blue); border: 1px solid #d2e9f1; }
    .warning { background: #fff6e8; border: 1px solid #f0ddb4; }
    .tip { background: var(--soft-mint); border: 1px solid #cfe8dc; }
    .checklist { list-style: none; padding: 0; display: grid; gap: 8px; }
    .checklist li { display: flex; gap: 8px; align-items: start; }
    .checklist li::before { content: "✓"; color: #168f72; font-weight: 900; }
    .diagram {
      background: var(--navy-900);
      color: #d7e7ef;
      font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
      white-space: pre;
      line-height: 1.45;
      padding: 18px 20px;
      border-radius: 16px;
      overflow-x: auto;
      margin: 14px 0;
    }
    .example { margin: 12px 0; border: 1px solid var(--line); border-radius: 14px; overflow: hidden; }
    .example .head { background: #edf3f7; padding: 8px 12px; font-size: .78rem; font-weight: 800; text-transform: uppercase; letter-spacing: .06em; color: var(--blue-700); }
    .example .body { padding: 12px; }
    .bad { color: #b42318; }
    .good { color: #087443; }
    .related { margin-top: 42px; }
    .related-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 16px;
    }
    .related-card {
      display: block;
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      padding: 18px;
      box-shadow: var(--shadow-soft);
      min-height: 100%;
    }
    .related-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
    .related-card b { display: block; margin-bottom: 8px; font-size: 1.02rem; color: var(--ink); }
    .related-card span { color: var(--muted); font-size: .92rem; }
    .nextprev {
      display: flex;
      justify-content: space-between;
      gap: 16px;
      margin-top: 22px;
    }
    .nextprev a { color: var(--blue-600); }
    .nextprev small { display: block; color: var(--muted); font-weight: 700; text-transform: uppercase; letter-spacing: .06em; font-size: .72rem; }
    .cta {
      margin-top: 28px;
      background: linear-gradient(135deg, var(--navy-950), var(--navy-800));
      color: #d7e7ef;
      border-radius: var(--radius-xl);
      padding: 28px 30px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 20px;
    }
    .cta h2 { color: var(--white); margin: 0 0 8px; font-size: 1.7rem; }
    .cta p { margin: 0; color: #b9ccd8; }
    @media (max-width: 980px) {
      .layout { grid-template-columns: 1fr; }
      .sidebar { position: static; }
      .related-grid { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 820px) {
      .learn-hero .hero-grid,
      .cta,
      .nextprev { grid-template-columns: 1fr; flex-direction: column; }
      .related-grid { grid-template-columns: 1fr; }
    }

    .crumb { padding: 16px 0 0; font-size: .88rem; color: var(--muted); }
    .crumb a { color: var(--blue-600); font-weight: 700; }
    .read {
      background: rgba(255,255,255,.09);
      border: 1px solid rgba(255,255,255,.16);
      border-radius: var(--radius-lg);
      padding: 22px 24px;
      color: #d8e7ef;
      align-self: center;
    }
    .read b { display: block; color: var(--white); font-size: 1.2rem; margin-bottom: 8px; }
    .side {
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: var(--radius-md);
      padding: 16px 16px 10px;
      box-shadow: var(--shadow-soft);
    }
    .side h3 { margin: 0 0 10px; font-size: .92rem; letter-spacing: -.01em; }
    .side a {
      display: block;
      padding: 7px 0;
      font-size: .86rem;
      color: #29475d;
      border-bottom: 1px solid #eef3f6;
    }
    .side a:last-child { border-bottom: 0; }
    .side a.active,
    .side a:hover { color: var(--blue-600); font-weight: 760; }
    .checks { list-style: none; padding: 0; display: grid; gap: 8px; }
    .checks li { display: flex; gap: 8px; align-items: start; }
    .checks li::before { content: "✓"; color: #168f72; font-weight: 900; }
    .hub,
    .cards {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 16px;
    }
    .card {
      display: block;
      background: var(--white);
      border: 1px solid var(--line);
      border-radius: var(--radius-lg);
      padding: 18px;
      box-shadow: var(--shadow-soft);
      min-height: 100%;
    }
    .card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
    .card b { display: block; margin: 6px 0 8px; font-size: 1.05rem; color: var(--ink); }
    .card span { color: var(--muted); font-size: .92rem; }
    .num {
      color: var(--blue-600);
      font-size: .74rem;
      font-weight: 800;
      letter-spacing: .08em;
      text-transform: uppercase;
    }
    @media (max-width: 980px) {
      .hub, .cards { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 820px) {
      .hub, .cards { grid-template-columns: 1fr; }
    }

    .pillars {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(210px, 1fr));
      gap: 18px;
      margin: 28px 0;
    }
    .pillar {
      border: 1px solid var(--line);
      border-radius: 18px;
      padding: 24px;
      background: #fbfdfe;
    }
    .pillar .label {
      font-size: .75rem;
      font-weight: 850;
      text-transform: uppercase;
      letter-spacing: .09em;
      color: var(--cyan-500);
    }
    .pillar h3 { margin: 8px 0; font-size: 1.25rem; }
    .pillar p { margin: 0; color: var(--muted); }
    .hub-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 16px;
      margin-top: 26px;
    }
    .hub-card {
      display: block;
      border: 1px solid var(--line);
      border-radius: 16px;
      padding: 20px;
      background: #fbfdfe;
      box-shadow: var(--shadow-soft);
      min-height: 100%;
    }
    .hub-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
    .hub-card .n {
      font-size: .75rem;
      font-weight: 850;
      color: var(--cyan-500);
      text-transform: uppercase;
      letter-spacing: .08em;
    }
    .hub-card h3 { margin: 8px 0; font-size: 1.16rem; color: var(--ink); }
    .hub-card p { font-size: .9rem; color: var(--muted); margin: 0; }
    .learn-page .checklist {
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 10px 18px;
    }
    .learn-page .checklist li {
      padding: 12px 13px;
      border: 1px solid var(--line);
      border-radius: 12px;
      background: #fbfdfe;
    }
    @media (max-width: 980px) {
      .hub-grid, .pillars { grid-template-columns: 1fr 1fr; }
    }
    @media (max-width: 820px) {
      .hub-grid, .pillars, .learn-page .checklist { grid-template-columns: 1fr; }
    }

    .learn-hero .hero-actions {
      display: flex;
      flex-wrap: wrap;
      gap: 12px;
      margin-top: 24px;
    }
    .learn-hero .btn-secondary {
      background: rgba(255,255,255,.08);
      color: var(--white);
      border-color: rgba(255,255,255,.18);
    }
    .problem-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 14px;
      margin: 20px 0 8px;
    }
    .problem-card {
      display: block;
      border: 1px solid var(--line);
      border-radius: 14px;
      padding: 18px;
      background: var(--white);
      box-shadow: var(--shadow-soft);
    }
    .problem-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
    .problem-card b { display: block; color: var(--ink); margin-bottom: 6px; }
    .problem-card span { font-size: .9rem; color: var(--muted); }
    .faq { border-top: 1px solid var(--line); margin-top: 18px; padding-top: 18px; }
    .faq h3 { margin-top: 20px; font-size: 1.05rem; }
    .question-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 14px;
      margin: 20px 0 8px;
    }
    .question-card {
      display: block;
      border: 1px solid var(--line);
      border-radius: 14px;
      padding: 18px;
      background: var(--white);
      box-shadow: var(--shadow-soft);
    }
    a.question-card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
    .question-card b { display: block; color: var(--ink); margin-bottom: 6px; }
    .question-card span { font-size: .9rem; color: var(--muted); }
    .answerbox {
      border: 1px solid var(--line);
      border-radius: 16px;
      overflow: hidden;
      margin: 24px 0;
    }
    .answerbox .head {
      background: var(--navy-900);
      color: var(--white);
      padding: 14px 18px;
      font-weight: 820;
    }
    .answerbox .body { padding: 20px; background: #fbfdfe; }
    .formbox {
      border: 1px solid var(--line);
      border-radius: 18px;
      padding: 22px;
      background: #fbfdfe;
      margin: 22px 0;
    }
    .field { margin-bottom: 14px; }
    .field label { display: block; font-weight: 800; color: var(--ink); margin-bottom: 6px; }
    .field input,
    .field textarea,
    .field select {
      width: 100%;
      border: 1px solid #cddce5;
      border-radius: 10px;
      padding: 12px;
      background: var(--white);
      font: inherit;
      color: var(--ink);
    }
    .field textarea { min-height: 110px; resize: vertical; }
    @media (max-width: 820px) {
      .problem-grid, .question-grid { grid-template-columns: 1fr; }
    }