*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
    :root{
      --bg:#f7f9fc;--surface:#fff;--surface-2:#f9fafb;--surface-3:#eff6ff;
      --border:#e5e7eb;--text:#111827;--muted:#4b5563;--dim:#6b7280;--soft:#9ca3af;
      --accent:#2563eb;--accent-dark:#1d4ed8;--accent-soft:#e0ecff;
      --success:#16a34a;--success-soft:#dcfce7;
      --warning:#d97706;--warning-soft:#fef3c7;
      --danger:#dc2626;--danger-soft:#fee2e2;
      --purple:#7c3aed;--purple-soft:#ede9fe;
      --teal:#0f766e;--teal-soft:#ccfbf1;
      --radius:18px;--shadow:0 10px 30px rgba(15,23,42,.04);
      --sans:Inter,Arial,sans-serif
    }
    html{scroll-behavior:smooth;overflow-x:hidden}
    body{background:var(--bg);color:var(--text);font-family:var(--sans);font-size:15px;line-height:1.7;-webkit-font-smoothing:antialiased;overflow-x:hidden}
    img,table,pre,iframe,video,canvas{max-width:100%}
    a{color:var(--accent);text-decoration:none}
    a:hover{text-decoration:underline}
    .hero,.article-hero,.hero-card,.content-card,.definition-card,.content-stack,.layout,.article-card,.sidebar,.sidebar-card,.related-card,.cta-block,.hub-cta,.calculator-callout,.formula-box,.table-wrap{max-width:100%;min-width:0}

    .site-header{position:sticky;top:0;z-index:1000;background:rgba(255,255,255,.92);backdrop-filter:blur(14px);border-bottom:1px solid var(--border)}
    .nav-wrap{max-width:1120px;margin:0 auto;padding:14px 20px;display:flex;align-items:center;justify-content:space-between;gap:18px}
    .brand{display:flex;align-items:center;gap:10px;font-size:18px;font-weight:800;color:var(--text);text-decoration:none}
    .brand:hover{text-decoration:none;color:var(--text)}
    .brand-mark{width:32px;height:32px;border-radius:10px;background:var(--accent);color:#fff;display:grid;place-items:center;font-weight:800}
    .top-nav{display:flex;align-items:center;gap:18px;font-size:14px;font-weight:600}
    .top-nav a{color:var(--muted);text-decoration:none}
    .top-nav a:hover{color:var(--accent);text-decoration:none}
    .menu-btn{display:none;background:none;border:none;cursor:pointer;padding:8px;color:var(--text);border-radius:8px;line-height:1}

    .mobile-nav{visibility:hidden;pointer-events:none;position:fixed;top:0;left:0;right:0;bottom:0;z-index:9999}
    .mobile-nav.open{visibility:visible;pointer-events:auto}
    .mobile-nav-overlay{position:absolute;top:0;left:0;right:0;bottom:0;background:rgba(15,23,42,.5)}
    .mobile-nav-panel{position:absolute;top:0;right:0;width:280px;max-width:85vw;height:100%;background:#fff;box-shadow:-4px 0 24px rgba(15,23,42,.15);display:flex;flex-direction:column;overflow-y:auto;transform:translateX(100%);transition:transform .25s ease}
    .mobile-nav.open .mobile-nav-panel{transform:translateX(0)}
    .mobile-nav-head{display:flex;align-items:center;justify-content:space-between;padding:18px 20px;border-bottom:1px solid var(--border);background:#fff}
    .mobile-nav-head strong{font-weight:800;font-size:16px;color:var(--text)}
    .mobile-nav-close{background:none;border:none;cursor:pointer;color:var(--dim);padding:6px;border-radius:8px;line-height:1;font-size:22px}
    .mobile-nav-links{flex:1}
    .mobile-nav-links a{display:block;padding:15px 20px;font-size:15px;font-weight:600;color:var(--text);border-bottom:1px solid var(--border);text-decoration:none}
    .mobile-nav-links a:active{background:var(--surface-2)}
    .mobile-nav-footer{padding:16px 20px;border-top:1px solid var(--border);font-size:12px;color:var(--dim)}

    .main{max-width:1120px;margin:0 auto;padding:20px 20px 70px}
    .breadcrumb{display:flex;align-items:center;gap:8px;font-size:13px;color:var(--dim);margin-bottom:14px;flex-wrap:wrap}
    .breadcrumb a{color:var(--muted);font-weight:600;text-decoration:none}
    .breadcrumb a:hover{color:var(--accent);text-decoration:none}

    .article-hero{padding:22px 28px;margin-bottom:20px;position:relative;background:linear-gradient(135deg,#fff 0%,#eff6ff 100%);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow)}
    .eyebrow{display:inline-flex;align-items:center;gap:8px;padding:5px 10px;font-size:12px;font-weight:800;letter-spacing:.04em;text-transform:uppercase;border-radius:999px;background:var(--accent-soft);color:var(--accent);margin-bottom:10px}
    h1{font-size:clamp(24px,3.4vw,38px);line-height:1.1;letter-spacing:-.04em;max-width:100%;margin-bottom:10px;color:var(--text)}
    .hero-subtitle{font-size:15px;line-height:1.6;max-width:100%;color:var(--muted)}
    .article-meta-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:14px}
    .meta-pill{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--border);background:#fff;border-radius:999px;padding:5px 10px;font-size:12px;font-weight:700;color:var(--muted)}
    .hero-search-panel{margin-top:14px;max-width:480px;position:relative;z-index:100}
    .hero-search-label{font-size:11.5px;font-weight:700;color:var(--muted);letter-spacing:.04em;text-transform:uppercase;margin-bottom:8px;display:block}
    .search-container{position:relative}
    .search-input-wrap{position:relative}
    .search-input{width:100%;padding:11px 14px 11px 40px;border-radius:12px;border:1px solid var(--border);background:var(--surface-2);color:var(--text);font-size:14px;font-family:var(--sans);outline:none;transition:border-color .15s ease,background .15s ease}
    .search-input:focus{border-color:var(--accent);background:#fff}
    .search-input::placeholder{color:var(--soft)}
    .search-icon{position:absolute;left:12px;top:50%;transform:translateY(-50%);color:var(--soft);pointer-events:none}
    .search-dropdown{position:absolute;left:0;right:0;top:calc(100% + 6px);background:var(--surface);border:1px solid var(--border);border-radius:14px;box-shadow:0 20px 40px rgba(15,23,42,.18);max-height:300px;overflow-y:auto;z-index:9999}
    .search-dropdown.hidden{display:none}
    .search-results{padding:4px 0}
    .search-result{display:flex;align-items:center;justify-content:space-between;gap:10px;padding:10px 14px;font-size:13.5px;color:var(--text);font-weight:600;border-bottom:1px solid var(--border);transition:background .1s ease;text-decoration:none;line-height:1.4}
    .search-result:last-child{border-bottom:0}
    .search-result:hover{background:var(--surface-2);text-decoration:none;color:var(--text)}
    .search-cat{font-size:11px;font-weight:700;color:var(--dim);background:var(--surface-2);padding:2px 7px;border-radius:999px;white-space:nowrap;flex-shrink:0}
    .search-empty{padding:12px 14px;font-size:13.5px;color:var(--dim)}

    .layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:24px;align-items:start}
    .content-stack{display:flex;flex-direction:column;gap:18px}
    .content-card,.article-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:24px;min-width:0;max-width:100%;overflow-wrap:break-word;word-wrap:break-word}
    .content-card h2,.article-card h2{font-size:23px;line-height:1.2;letter-spacing:-.02em;margin-bottom:12px;color:var(--text)}
    .content-card h3,.article-card h3{font-size:17px;line-height:1.3;margin:18px 0 8px;color:var(--text)}
    .content-card p,.article-card p{color:var(--muted);margin-bottom:12px}
    .content-card p:last-child,.article-card p:last-child{margin-bottom:0}
    .content-card ul,.article-card ul,.content-card ol,.article-card ol{margin:10px 0 12px 20px;color:var(--muted)}
    .content-card li,.article-card li{margin-bottom:6px}
    .content-card strong,.article-card strong{color:var(--text)}

    .summary-box{border:1px solid var(--accent-soft);background:var(--surface-3);border-radius:16px;padding:16px;margin:14px 0}
    .summary-box strong{display:block;margin-bottom:4px;color:var(--text)}
    .formula-box{background:#0f172a;color:#e5e7eb;border-radius:16px;padding:16px;overflow-x:auto;max-width:100%;margin:14px 0}
    .formula-box code{display:block;max-width:100%;white-space:pre;font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:13px;line-height:1.7}
    .table-wrap{width:100%;max-width:100%;overflow-x:auto;margin:14px 0;border:1px solid var(--border);border-radius:16px;background:#fff}
    table{width:100%;border-collapse:collapse;min-width:620px}
    th,td{padding:12px 14px;border-bottom:1px solid var(--border);text-align:left;vertical-align:top;font-size:14px}
    th{background:var(--surface-2);font-size:12px;text-transform:uppercase;letter-spacing:.06em;color:var(--dim);font-weight:800}
    tr:last-child td{border-bottom:0}

    .calculator-callout{display:flex;align-items:center;justify-content:space-between;gap:16px;background:linear-gradient(135deg,var(--accent-soft),#fff);border:1px solid #bfdbfe;border-radius:18px;padding:18px;overflow:hidden;margin:14px 0}
    .calculator-callout h3{margin:0 0 4px;font-size:17px}
    .calculator-callout p{margin:0;color:var(--muted);font-size:14px}
    .btn{display:inline-flex;align-items:center;justify-content:center;gap:8px;border-radius:12px;padding:11px 15px;border:1px solid transparent;font-size:14px;font-weight:800;cursor:pointer;text-decoration:none;line-height:1.2;white-space:nowrap}
    .btn:hover{text-decoration:none}
    .btn-primary{background:var(--accent);color:#fff}
    .btn-primary:hover{background:var(--accent-dark);color:#fff}
    .btn-secondary{background:#fff;color:var(--text);border-color:var(--border)}
    .btn-secondary:hover{border-color:var(--accent);color:var(--accent)}
    .inline-note{background:var(--warning-soft);border:1px solid #fde68a;border-radius:14px;padding:12px 14px;color:#92400e;font-size:14px;margin:14px 0}
    .check-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:12px}
    .check-card{border:1px solid var(--border);background:var(--surface-2);border-radius:14px;padding:13px;min-width:0}
    .check-card strong{display:block;font-size:14px;margin-bottom:4px}
    .check-card span{display:block;color:var(--muted);font-size:13.5px;line-height:1.5}

    .sidebar{position:sticky;top:86px;display:flex;flex-direction:column;gap:14px;min-width:0;max-width:100%}
    .sidebar-card{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:var(--shadow);padding:16px;min-width:0;max-width:100%}
    .sidebar-card h2{font-size:13px;text-transform:uppercase;letter-spacing:.08em;color:var(--dim);margin-bottom:10px}
    .toc{display:flex;flex-direction:column;gap:0}
    .toc a{display:block;padding:9px 0;border-bottom:1px solid var(--border);font-size:14px;font-weight:600;color:var(--text);text-decoration:none;line-height:1.35}
    .toc a:last-child{border-bottom:0}
    .toc a:hover{color:var(--accent);text-decoration:none}
    .toc-select{display:none;width:100%;padding:10px 12px;border:1px solid var(--border);border-radius:12px;background:#fff;color:var(--text);font-size:14px;font-weight:600;cursor:pointer}
    .sidebar-cta{background:linear-gradient(135deg,#111827,#1f2937);color:#fff;border-color:#111827}
    .sidebar-cta h2{color:#c7d2fe}
    .sidebar-cta p{color:#e5e7eb;font-size:14px;margin-bottom:12px}
    .sidebar-cta .btn{width:100%}

    .related-guide-nav,.also-useful-nav,.quick-links-nav{display:flex;flex-direction:column;gap:0}
    .related-guide-nav a,.also-useful-nav a,.quick-links-nav a{display:block;padding:10px 0;font-size:14px;font-weight:600;color:var(--text);border-bottom:1px solid var(--border);text-decoration:none;line-height:1.4}
    .related-guide-nav a:last-child,.also-useful-nav a:last-child,.quick-links-nav a:last-child{border-bottom:0}
    .related-guide-nav a:hover,.also-useful-nav a:hover,.quick-links-nav a:hover{color:var(--accent);text-decoration:none}
    .related-sidebar-mobile,.also-useful-sidebar-mobile,.quick-links-sidebar-mobile{display:none;padding:0 12px 24px;box-sizing:border-box;width:100%}

    .faq-item{border-top:1px solid var(--border);padding:14px 0}
    .faq-item:first-of-type{border-top:0;padding-top:0}
    .faq-item h3{font-size:16px;margin:0 0 6px}
    .source-list{font-size:13.5px;color:var(--muted)}
    .source-list li{margin-bottom:8px}

    .footer{border-top:1px solid var(--border);background:#fff;padding:40px 20px 24px;margin-top:40px}
    .footer-inner{max-width:1120px;margin:0 auto}
    .footer-cols{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:32px;margin-bottom:32px}
    .footer-col h4{font-size:11px;font-weight:800;letter-spacing:.08em;text-transform:uppercase;color:var(--dim);margin-bottom:12px}
    .footer-col ul{list-style:none;display:flex;flex-direction:column;gap:8px;margin:0}
    .footer-col ul li{margin:0}
    .footer-col ul li a{color:var(--muted);font-size:13px;font-weight:600;transition:color .12s ease;text-decoration:none}
    .footer-col ul li a:hover{color:var(--accent);text-decoration:none}
    .footer-base{border-top:1px solid var(--border);padding-top:20px;color:var(--dim);font-size:12px}

    @media(max-width:980px){
      .layout{display:flex;flex-direction:column}
      .sidebar{position:static;order:-1;width:100%}
      .toc{display:none}.toc-select{display:block}
      .check-grid{grid-template-columns:1fr}
      .related-sidebar{display:none}.also-useful-sidebar{display:none}.quick-links-sidebar{display:none}
      .related-sidebar-mobile{display:block}.also-useful-sidebar-mobile{display:block}.quick-links-sidebar-mobile{display:block}
    }
    @media(max-width:760px){
      .top-nav{display:none}.menu-btn{display:block}
      .main{padding:16px 12px 48px}
      .article-hero,.hero,.hero-card{padding:16px}
      .content-card,.definition-card,.article-card{padding:16px}
      .sidebar-card{padding:14px}
      .cta-block,.hub-cta{padding:16px}
      h1{font-size:22px}
      h2{font-size:19px;margin-bottom:10px}
      h3{font-size:16px}
      .hero-subtitle{font-size:14px}
      .calculator-callout{display:block}
      .calculator-callout .btn{margin-top:12px;display:block;text-align:center;width:100%;box-sizing:border-box}
      .btn{width:100%;box-sizing:border-box}
      .hero-search-panel{max-width:100%}
      .footer-cols{grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}
      table{min-width:560px}
    }
    @media(max-width:420px){.footer-cols{grid-template-columns:1fr}}

    /* Glossary definition page blocks */
    .article-meta-pill{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--border);background:#fff;border-radius:999px;padding:5px 10px;font-size:12px;font-weight:700;color:var(--muted)}
    .definition-box{border:1px solid var(--accent-soft);border-radius:16px;background:var(--surface-3);padding:16px;margin:14px 0}
    .definition-box strong{display:block;margin-bottom:4px;color:var(--text)}
    .definition-box p{margin:0;color:var(--muted);line-height:1.65}
    .summary-box,.answer-box{border:1px solid var(--accent-soft);background:var(--surface-3);border-radius:16px;padding:16px;margin:14px 0}
    .summary-box strong,.answer-box strong{display:block;margin-bottom:4px;color:var(--text)}
    .summary-box p,.answer-box p{margin:0;color:var(--muted);line-height:1.65}
    .term-summary-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px;margin-top:14px}
    .term-summary-card{border:1px solid var(--border);border-radius:16px;background:var(--surface-2);padding:14px;min-width:0}
    .term-summary-card strong{display:block;font-size:13px;text-transform:uppercase;letter-spacing:.06em;color:var(--dim);margin-bottom:4px}
    .term-summary-card span{display:block;font-size:15px;font-weight:800;color:var(--text);line-height:1.35}
    .term-list{display:grid;gap:10px;margin-top:10px}
    .term-list-item{border:1px solid var(--border);border-radius:14px;background:var(--surface-2);padding:12px;min-width:0}
    .term-list-item strong{display:block;color:var(--text);font-size:14px;margin-bottom:3px}
    .term-list-item span{display:block;color:var(--muted);font-size:13.5px;line-height:1.5}
    .glossary-pills{display:flex;flex-wrap:wrap;gap:8px;margin-top:12px}
    .glossary-pill{display:inline-flex;align-items:center;background:var(--surface-2);border:1px solid var(--border);border-radius:999px;padding:6px 10px;font-size:12px;font-weight:800;color:var(--muted);text-decoration:none}
    .glossary-pill:hover{border-color:var(--accent);color:var(--accent);background:#fff;text-decoration:none}
    @media(max-width:760px){.term-summary-grid{grid-template-columns:1fr}}