:root {
      --blue: #003a8c;
      --blue-2: #0059d1;
      --navy: #061b3b;
      --navy-2: #0b2b63;
      --red: #ed1212;
      --red-2: #b60000;
      --paper: #ffffff;
      --soft: #f5f8ff;
      --soft-blue: #eaf1ff;
      --ink: #071225;
      --muted: #5f6c80;
      --line: rgba(0, 58, 140, 0.18);
      --shadow: 0 26px 80px rgba(6, 27, 59, 0.16);
      --radius: 26px;
      --max: 1200px;
    }

    * { box-sizing: border-box; }
    html { scroll-behavior: smooth; }
    body {
      margin: 0;
      color: var(--ink);
      font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
      line-height: 1.62;
      background:
        radial-gradient(circle at 8% 4%, rgba(237, 18, 18, .12), transparent 30rem),
        radial-gradient(circle at 92% 0%, rgba(0, 58, 140, .16), transparent 32rem),
        linear-gradient(180deg, #ffffff 0%, #f8fbff 44%, #ffffff 100%);
    }

    a { color: inherit; }
    img { max-width: 100%; display: block; }

    .skip-link {
      position: absolute;
      left: -999px;
      top: 1rem;
      z-index: 200;
      background: var(--blue);
      color: #fff;
      padding: .75rem 1rem;
      border-radius: 999px;
      text-decoration: none;
      font-weight: 800;
    }
    .skip-link:focus { left: 1rem; }

    .site-header {
      position: sticky;
      top: 0;
      z-index: 100;
      background: rgba(255, 255, 255, .9);
      backdrop-filter: blur(18px);
      border-bottom: 1px solid var(--line);
    }
    .nav-shell {
      width: min(var(--max), calc(100% - 32px));
      margin: 0 auto;
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1rem;
      min-height: 82px;
    }
    .brand {
      display: inline-flex;
      align-items: center;
      gap: .85rem;
      text-decoration: none;
      min-width: max-content;
    }
    .brand img {
      width: 58px;
      height: 58px;
      object-fit: cover;
      border: 4px solid var(--blue);
      background: #fff;
      box-shadow: 0 10px 24px rgba(0, 58, 140, .22);
    }
    .brand strong {
      display: block;
      color: var(--blue);
      font-size: 1.08rem;
      letter-spacing: .02em;
      line-height: 1;
    }
    .brand span {
      display: block;
      margin-top: .22rem;
      color: var(--muted);
      font-size: .74rem;
      font-weight: 800;
      letter-spacing: .12em;
      text-transform: uppercase;
    }
    .main-nav {
      display: flex;
      align-items: center;
      gap: .28rem;
    }
    .main-nav a {
      position: relative;
      display: inline-flex;
      align-items: center;
      gap: .4rem;
      text-decoration: none;
      color: var(--navy);
      font-size: .92rem;
      font-weight: 850;
      padding: .66rem .85rem;
      border-radius: 999px;
      white-space: nowrap;
      transition: background .2s ease, color .2s ease, transform .2s ease;
    }
    .main-nav .nav-icon {
      width: 1.05rem;
      height: 1.05rem;
      color: var(--red);
      flex: 0 0 auto;
      transition: color .2s ease, transform .2s ease;
    }
    .main-nav a:hover .nav-icon,
    .main-nav a.active .nav-icon {
      color: var(--blue);
      transform: translateY(-1px);
    }
    .main-nav a:hover,
    .main-nav a.active {
      color: var(--blue);
      background: var(--soft-blue);
      transform: translateY(-1px);
    }
    .main-nav a.active {
      font-weight: 900;
    }
    .main-nav a.active::after {
      content: "";
      position: absolute;
      left: .85rem;
      right: .85rem;
      bottom: .28rem;
      height: 2.5px;
      border-radius: 2px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    .nav-toggle {
      display: none;
      width: 48px;
      height: 44px;
      border-radius: 14px;
      border: 1px solid var(--line);
      background: #fff;
      cursor: pointer;
      padding: 0;
    }
    .nav-toggle span {
      display: block;
      width: 22px;
      height: 2px;
      margin: 5px auto;
      background: var(--blue);
      border-radius: 99px;
    }

    .section {
      position: relative;
      overflow: hidden;
      padding: clamp(4.25rem, 8vw, 7.5rem) 0;
      scroll-margin-top: 90px;
    }
    .container {
      width: min(var(--max), calc(100% - 32px));
      margin: 0 auto;
    }
    .two-col {
      display: grid;
      grid-template-columns: minmax(0, 1fr) minmax(320px, .92fr);
      gap: clamp(2rem, 5vw, 4.5rem);
      align-items: center;
    }
    .section-heading {
      max-width: 860px;
      margin-bottom: 2.4rem;
    }
    .section-heading.center {
      text-align: center;
      margin-left: auto;
      margin-right: auto;
    }
    .eyebrow {
      display: inline-flex;
      align-items: center;
      gap: .55rem;
      margin: 0 0 .9rem;
      color: var(--red-2);
      font-size: .78rem;
      font-weight: 900;
      letter-spacing: .15em;
      text-transform: uppercase;
    }
    .eyebrow::before {
      content: "";
      width: 38px;
      height: 3px;
      border-radius: 999px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    h1, h2, h3 { margin: 0; line-height: 1.06; color: var(--navy); }
    h1 {
      max-width: 920px;
      font-size: clamp(2.8rem, 6.3vw, 6.5rem);
      letter-spacing: -.065em;
    }
    h2 {
      font-size: clamp(2.05rem, 4vw, 4.3rem);
      letter-spacing: -.052em;
    }
    h3 {
      font-size: clamp(1.2rem, 2vw, 1.56rem);
      letter-spacing: -.02em;
    }
    p { margin: 0 0 1rem; }
    .lead {
      margin-top: 1.15rem;
      color: var(--muted);
      font-size: clamp(1.08rem, 1.6vw, 1.32rem);
      max-width: 68ch;
    }
    .support-copy { color: var(--muted); max-width: 72ch; }

    .button-row {
      display: flex;
      flex-wrap: wrap;
      gap: .9rem;
      margin: 2rem 0;
    }
    .button {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      min-height: 3.15rem;
      padding: .84rem 1.18rem;
      border-radius: 999px;
      border: 2px solid transparent;
      text-decoration: none;
      font-weight: 900;
      cursor: pointer;
      transition: transform .2s ease, box-shadow .2s ease, background .2s ease;
      font: inherit;
    }
    .button:hover { transform: translateY(-2px); }
    .button.primary {
      color: #fff;
      background: linear-gradient(135deg, var(--blue), var(--red));
      box-shadow: 0 18px 35px rgba(0, 58, 140, .26);
    }
    .button.secondary {
      color: var(--blue);
      background: #fff;
      border-color: rgba(0, 58, 140, .22);
    }

    .hero {
      min-height: calc(100vh - 82px);
      display: flex;
      align-items: center;
      padding-top: clamp(3.5rem, 7vw, 6.8rem);
    }
    .hero::after {
      content: "";
      position: absolute;
      right: -13rem;
      top: 11rem;
      width: 36rem;
      height: 36rem;
      border: 44px solid rgba(237, 18, 18, .08);
      border-radius: 50%;
      transform: rotate(18deg);
      pointer-events: none;
    }
    .hero-copy { position: relative; z-index: 2; }
    .hero-side {
      position: relative;
      z-index: 2;
      display: grid;
      gap: 1rem;
      align-self: start;
      padding-top: 2.15rem;
    }
    .hero-stress-card {
      margin: 0;
      border: 1px solid rgba(0, 58, 140, .2);
      border-radius: var(--radius);
      background:
        linear-gradient(180deg, rgba(255, 255, 255, .96), rgba(245, 248, 255, .94)),
        radial-gradient(circle at 12% 10%, rgba(237, 18, 18, .12), transparent 18rem);
      box-shadow: var(--shadow);
      padding: .8rem;
      overflow: hidden;
    }
    .hero-stress-card img {
      width: 100%;
      height: auto;
      border-radius: 20px;
      border: 1px solid rgba(0, 58, 140, .14);
      background: #fff;
    }
    .hero-stress-card figcaption {
      display: flex;
      flex-wrap: wrap;
      gap: .35rem;
      align-items: baseline;
      padding: .8rem .4rem .2rem;
      color: var(--muted);
      font-size: .93rem;
      line-height: 1.45;
    }
    .hero-stress-card figcaption strong {
      color: var(--red-2);
      text-transform: uppercase;
      letter-spacing: .08em;
      font-size: .8rem;
    }
    .metrics {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: .85rem;
      margin-top: 1.8rem;
    }
    .metric {
      border: 1px solid var(--line);
      background: rgba(255, 255, 255, .78);
      border-radius: 22px;
      padding: 1rem;
      box-shadow: 0 10px 26px rgba(6, 27, 59, .06);
    }
    .metric b {
      display: block;
      color: var(--red);
      font-size: clamp(1.65rem, 3vw, 2.4rem);
      line-height: 1;
      letter-spacing: -.04em;
    }
    .metric span {
      display: block;
      margin-top: .35rem;
      color: var(--muted);
      font-size: .88rem;
      font-weight: 750;
    }

    .analysis-panel {
      position: relative;
      z-index: 2;
      border: 1px solid rgba(0, 58, 140, .2);
      border-radius: var(--radius);
      background:
        linear-gradient(180deg, rgba(255, 255, 255, .94), rgba(245, 248, 255, .92)),
        radial-gradient(circle at 92% 8%, rgba(237, 18, 18, .18), transparent 18rem);
      box-shadow: var(--shadow);
      padding: clamp(1.2rem, 3vw, 2rem);
      overflow: hidden;
    }
    .panel-head {
      display: flex;
      justify-content: space-between;
      align-items: center;
      gap: 1rem;
      margin-bottom: 1.2rem;
    }
    .panel-head img {
      width: 92px;
      height: 82px;
      object-fit: cover;
      border: 4px solid var(--blue);
      background: #fff;
    }
    .panel-head span {
      color: var(--red-2);
      font-weight: 900;
      text-transform: uppercase;
      letter-spacing: .12em;
      font-size: .72rem;
      text-align: right;
    }
    .equation {
      display: block;
      margin: .8rem 0;
      border: 1px solid rgba(0, 58, 140, .16);
      border-radius: 18px;
      background: #fff;
      padding: .95rem 1rem;
      color: var(--navy);
      font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;
      font-size: clamp(.96rem, 1.45vw, 1.1rem);
      overflow-x: auto;
      white-space: nowrap;
    }
    .equation.large {
      color: #fff;
      border-color: transparent;
      background: linear-gradient(135deg, var(--navy), var(--blue) 60%, var(--red));
      font-size: clamp(1.05rem, 2vw, 1.4rem);
      padding: 1.25rem;
      box-shadow: 0 18px 42px rgba(0, 58, 140, .2);
    }
    .eq-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: .9rem;
      margin-top: .9rem;
    }
    .mini-eq {
      border: 1px solid rgba(0, 58, 140, .16);
      background: #fff;
      border-radius: 18px;
      padding: .95rem;
    }
    .mini-eq b {
      display: block;
      color: var(--red-2);
      font-size: .78rem;
      letter-spacing: .08em;
      text-transform: uppercase;
      margin-bottom: .5rem;
    }
    .panel-note {
      margin: 1.05rem 0 0;
      color: var(--muted);
      font-size: .95rem;
    }

    .origin-cards {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 1rem;
      margin-top: 2.2rem;
    }
    .origin-card, .tool-card, .math-card, .application-card, .contact-card {
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: rgba(255, 255, 255, .9);
      box-shadow: 0 18px 46px rgba(6, 27, 59, .08);
      padding: clamp(1.1rem, 2.5vw, 1.55rem);
    }
    .origin-card b {
      display: block;
      margin-bottom: .45rem;
      color: var(--red);
      font-size: 2rem;
      letter-spacing: -.04em;
    }
    .origin-card span { color: var(--muted); }

    .dark {
      color: #fff;
      background:
        radial-gradient(circle at 20% 12%, rgba(237, 18, 18, .22), transparent 26rem),
        radial-gradient(circle at 88% 74%, rgba(0, 89, 209, .36), transparent 25rem),
        linear-gradient(135deg, #061b3b 0%, #082555 50%, #030b18 100%);
    }
    .dark h2, .dark h3 { color: #fff; }
    .dark .eyebrow { color: #ffb2b2; }
    .dark .support-copy, .dark .lead { color: rgba(255, 255, 255, .76); }
    .dark .math-card {
      background: rgba(255, 255, 255, .075);
      border-color: rgba(255, 255, 255, .16);
      box-shadow: none;
      backdrop-filter: blur(12px);
    }
    .dark .equation {
      color: #fff;
      background: rgba(255, 255, 255, .08);
      border-color: rgba(255, 255, 255, .16);
    }
    .math-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 1rem;
      margin-top: 2.1rem;
    }
    .math-card p, .tool-card p, .application-card p { color: var(--muted); }
    .dark .math-card p { color: rgba(255, 255, 255, .74); }
    .method-strip {
      display: grid;
      grid-template-columns: repeat(4, minmax(0, 1fr));
      gap: .85rem;
      margin-top: 1.6rem;
    }
    .method-step {
      border: 1px solid rgba(255, 255, 255, .16);
      border-radius: 20px;
      background: rgba(255, 255, 255, .07);
      padding: 1rem;
    }
    .method-step b {
      display: inline-flex;
      width: 32px;
      height: 32px;
      align-items: center;
      justify-content: center;
      border-radius: 999px;
      margin-bottom: .65rem;
      background: var(--red);
      color: #fff;
    }
    .method-step span { display: block; color: rgba(255, 255, 255, .78); font-size: .92rem; }

    .tool-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 1rem;
    }
    .tool-card {
      position: relative;
      overflow: hidden;
      min-height: 245px;
    }
    .tool-card::before {
      content: "";
      position: absolute;
      inset: 0 0 auto 0;
      height: 6px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    .tool-card h3 { margin-bottom: .7rem; }
    .tool-card .tag {
      display: inline-flex;
      margin-top: .4rem;
      border-radius: 999px;
      background: var(--soft-blue);
      color: var(--blue);
      padding: .36rem .6rem;
      font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
      font-size: .82rem;
      font-weight: 800;
    }

    .extra-tool-grid {
      margin-top: 1rem;
    }
    .extra-tool-card {
      min-height: 168px;
      display: grid;
      align-content: start;
      gap: .75rem;
      background: linear-gradient(180deg, rgba(255,255,255,.96), rgba(245,248,255,.96));
    }
    .extra-tool-number {
      display: inline-flex;
      width: 36px;
      height: 36px;
      align-items: center;
      justify-content: center;
      border-radius: 999px;
      background: linear-gradient(135deg, var(--blue), var(--red));
      color: #fff;
      font-size: .86rem;
      font-weight: 950;
      line-height: 1;
    }
    .extra-tool-card p {
      margin: 0;
      color: var(--navy);
      font-size: 1rem;
      font-weight: 780;
      line-height: 1.45;
    }
    .extra-tool-image {
      margin: .15rem 0 0;
      border: 1px solid rgba(0, 58, 140, .16);
      border-radius: 18px;
      background: #fff;
      padding: .45rem;
      box-shadow: 0 12px 28px rgba(6, 27, 59, .08);
    }
    .extra-tool-link {
      justify-self: start;
      min-height: 2.4rem;
      padding: .5rem 1.05rem;
      font-size: .88rem;
      font-weight: 800;
    }
    .extra-tool-link-disabled {
      color: var(--muted);
      background: rgba(95, 108, 128, .07);
      border-color: rgba(95, 108, 128, .18);
      cursor: default;
    }
    .extra-tool-link-disabled:hover {
      transform: none;
    }
    .extra-tool-image img {
      width: 100%;
      height: auto;
      border-radius: 12px;
      background: #fff;
    }
    .extra-tool-image-pending {
      display: flex;
    }
    .image-pending-box {
      width: 100%;
      min-height: 160px;
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: .4rem;
      border-radius: 12px;
      background: repeating-linear-gradient(135deg, rgba(95,108,128,.05), rgba(95,108,128,.05) 10px, rgba(95,108,128,.09) 10px, rgba(95,108,128,.09) 20px);
      border: 1px dashed rgba(95,108,128,.35);
    }
    .image-pending-icon {
      font-size: 1.6rem;
      opacity: .5;
    }
    .image-pending-text {
      color: var(--muted);
      font-size: .78rem;
      font-weight: 800;
      text-transform: uppercase;
      letter-spacing: .04em;
    }


    .program-showcase {
      margin-top: clamp(2.2rem, 5vw, 3.4rem);
    }
    .subsection-head {
      margin-bottom: 1.4rem;
      max-width: 920px;
    }
    .mini-eyebrow {
      display: inline-flex;
      align-items: center;
      gap: .5rem;
      margin: 0 0 .85rem;
      color: var(--red-2);
      font-size: .75rem;
      font-weight: 900;
      letter-spacing: .14em;
      text-transform: uppercase;
    }
    .mini-eyebrow::before {
      content: "";
      width: 28px;
      height: 3px;
      border-radius: 999px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    .program-highlight {
      display: grid;
      grid-template-columns: minmax(280px, .82fr) minmax(0, 1.18fr);
      gap: 1rem;
      align-items: stretch;
      margin-bottom: 1rem;
    }
    .program-copy {
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: linear-gradient(180deg, #f9fbff, #eef4ff);
      box-shadow: 0 18px 46px rgba(6, 27, 59, .08);
      padding: clamp(1.1rem, 2.5vw, 1.55rem);
    }
    .program-copy h3 {
      margin-bottom: .8rem;
    }
    .program-points {
      list-style: none;
      padding: 0;
      margin: 1rem 0 0;
      display: grid;
      gap: .75rem;
    }
    .program-points li {
      display: grid;
      grid-template-columns: 28px 1fr;
      gap: .75rem;
      align-items: start;
      color: var(--muted);
    }
    .program-points b {
      display: inline-flex;
      width: 28px;
      height: 28px;
      align-items: center;
      justify-content: center;
      border-radius: 999px;
      background: var(--blue);
      color: #fff;
      font-size: .84rem;
      line-height: 1;
    }
    .screenshot-grid {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      gap: 1rem;
      margin-top: 1rem;
    }
    .shot-card {
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: rgba(255, 255, 255, .95);
      box-shadow: 0 18px 46px rgba(6, 27, 59, .08);
      padding: .9rem;
      overflow: hidden;
    }
    .shot-card img {
      width: 100%;
      height: auto;
      border-radius: 18px;
      border: 1px solid rgba(0, 58, 140, .12);
      background: #fff;
    }
    .shot-card.feature {
      padding-bottom: 1rem;
    }
    .shot-card figcaption {
      margin-top: .8rem;
      color: var(--muted);
      font-size: .95rem;
    }
    .shot-card strong {
      color: var(--navy);
    }

    .applications {
      background:
        linear-gradient(180deg, rgba(255, 255, 255, .92), rgba(245, 248, 255, .96)),
        repeating-linear-gradient(90deg, rgba(0, 58, 140, .05) 0 1px, transparent 1px 42px),
        repeating-linear-gradient(0deg, rgba(0, 58, 140, .05) 0 1px, transparent 1px 42px);
    }
    .aero-visual {
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: #fff;
      box-shadow: var(--shadow);
      padding: 1.2rem;
    }
    .aero-visual svg { width: 100%; height: auto; overflow: visible; }
    .application-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 1rem;
      margin-top: 1.6rem;
    }
    .application-card h3 { margin-bottom: .55rem; }



    .people {
      background:
        radial-gradient(circle at 86% 12%, rgba(237, 18, 18, .10), transparent 30rem),
        radial-gradient(circle at 12% 88%, rgba(0, 58, 140, .13), transparent 34rem),
        linear-gradient(180deg, #ffffff, #f5f8ff 55%, #ffffff);
    }
    .people-feature {
      display: grid;
      grid-template-columns: minmax(0, 1.2fr) minmax(280px, .8fr);
      gap: 1rem;
      align-items: stretch;
      margin-bottom: 1rem;
    }
    .legacy-card,
    .person-card {
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: rgba(255, 255, 255, .92);
      box-shadow: 0 18px 46px rgba(6, 27, 59, .08);
      padding: clamp(1.1rem, 2.5vw, 1.55rem);
    }
    .legacy-card {
      position: relative;
      overflow: hidden;
    }
    .legacy-card::before {
      content: "";
      position: absolute;
      inset: 0 auto 0 0;
      width: 7px;
      background: linear-gradient(180deg, var(--blue), var(--red));
    }
    .legacy-card h3 {
      margin-bottom: .85rem;
    }
    .legacy-equation {
      display: flex;
      flex-direction: column;
      justify-content: center;
      background:
        linear-gradient(135deg, rgba(6, 27, 59, .96), rgba(0, 58, 140, .88)),
        repeating-linear-gradient(90deg, rgba(255,255,255,.08) 0 1px, transparent 1px 32px);
      color: #fff;
      border-color: rgba(255, 255, 255, .16);
    }
    .legacy-equation .equation {
      color: #fff;
      background: rgba(255, 255, 255, .08);
      border-color: rgba(255, 255, 255, .16);
      margin: .9rem 0 0;
    }
    .legacy-equation p {
      color: rgba(255, 255, 255, .78);
      margin: 0;
    }
    .people-grid {
      display: grid;
      grid-template-columns: repeat(3, minmax(0, 1fr));
      gap: 1rem;
      margin-top: 1rem;
    }
    .person-card {
      position: relative;
      overflow: hidden;
      min-height: 230px;
    }
    .person-card::before {
      content: "";
      position: absolute;
      inset: 0 0 auto 0;
      height: 6px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    .person-icon {
      display: inline-flex;
      width: 46px;
      height: 46px;
      align-items: center;
      justify-content: center;
      border-radius: 16px;
      margin-bottom: .9rem;
      color: #fff;
      background: linear-gradient(135deg, var(--blue), var(--red));
      box-shadow: 0 14px 28px rgba(0, 58, 140, .18);
      font-weight: 950;
      font-size: 1.15rem;
    }
    .person-card h3 {
      margin-bottom: .65rem;
    }
    .person-card p {
      color: var(--muted);
    }

    .named-people {
      display: grid;
      grid-template-columns: repeat(2, minmax(0, 1fr));
      align-items: start;
      gap: 1rem;
      margin: 1.4rem 0 1rem;
    }
    .profile-card {
      display: grid;
      grid-template-columns: minmax(170px, .42fr) minmax(0, 1fr);
      gap: 1.1rem;
      align-items: stretch;
      border: 1px solid var(--line);
      border-radius: var(--radius);
      background: rgba(255, 255, 255, .94);
      box-shadow: 0 20px 54px rgba(6, 27, 59, .10);
      padding: clamp(1rem, 2.3vw, 1.35rem);
      overflow: hidden;
      position: relative;
    }
    .profile-card::before {
      content: "";
      position: absolute;
      inset: 0 0 auto 0;
      height: 7px;
      background: linear-gradient(90deg, var(--blue), var(--red));
    }
    .profile-media {
      min-height: 260px;
      margin: 0;
      border-radius: 22px;
      border: 1px solid rgba(0, 58, 140, .14);
      background: linear-gradient(135deg, #f5f8ff, #ffffff);
      overflow: hidden;
      box-shadow: inset 0 0 0 1px rgba(255,255,255,.5);
      display: flex;
      flex-direction: column;
    }
    .profile-media img {
      width: 100%;
      flex: 1 1 auto;
      min-height: 0;
      object-fit: cover;
      object-position: center top;
    }
    .profile-media figcaption {
      flex: 0 0 auto;
      padding: .85rem 1rem 1rem;
      color: var(--muted);
      font-size: .92rem;
      line-height: 1.45;
      background: rgba(255,255,255,.96);
      border-top: 1px solid rgba(0, 58, 140, .10);
    }
    .profile-media figcaption strong {
      color: var(--navy);
    }
    .profile-card.profile-wide {
      grid-column: 1 / -1;
      grid-template-columns: 1fr;
    }
    .profile-card.profile-wide .profile-media {
      min-height: auto;
    }
    .profile-card.profile-wide .profile-media img {
      display: block;
      width: 100%;
      height: auto;
      object-fit: contain;
      object-position: center center;
      background: #f5f8ff;
    }
    .profile-initials {
      display: flex;
      flex-direction: column;
      align-items: center;
      justify-content: center;
      text-align: center;
      color: #fff;
      background:
        radial-gradient(circle at 25% 20%, rgba(237, 18, 18, .9), transparent 10rem),
        linear-gradient(135deg, var(--navy), var(--blue));
    }
    .profile-initials span {
      display: inline-flex;
      width: 96px;
      height: 96px;
      align-items: center;
      justify-content: center;
      border: 2px solid rgba(255,255,255,.44);
      border-radius: 28px;
      font-size: 2.35rem;
      font-weight: 950;
      letter-spacing: -.04em;
      background: rgba(255,255,255,.10);
    }
    .profile-initials small {
      margin-top: .9rem;
      color: rgba(255,255,255,.78);
      font-weight: 850;
      letter-spacing: .11em;
      text-transform: uppercase;
    }
    .profile-kicker {
      margin: .15rem 0 .45rem;
      color: var(--red-2);
      font-size: .75rem;
      font-weight: 900;
      letter-spacing: .12em;
      text-transform: uppercase;
    }
    .profile-card h3 {
      margin-bottom: .7rem;
    }
    .profile-card p {
      color: var(--muted);
    }
    .profile-card p a {
      color: var(--blue);
      font-weight: 700;
      text-decoration-color: rgba(0, 58, 140, .35);
    }
    .profile-card p a:hover {
      color: var(--red);
    }
    .profile-tags {
      display: flex;
      flex-wrap: wrap;
      gap: .45rem;
      margin-top: .8rem;
    }
    .profile-tags span {
      border-radius: 999px;
      background: var(--soft-blue);
      color: var(--blue);
      padding: .36rem .62rem;
      font-size: .8rem;
      font-weight: 850;
    }

    .people-note {
      margin-top: 1rem;
      border: 1px dashed rgba(0, 58, 140, .28);
      border-radius: 20px;
      background: rgba(234, 241, 255, .72);
      padding: 1rem 1.1rem;
      color: var(--muted);
    }

    .contact {
      background:
        radial-gradient(circle at 12% 18%, rgba(237, 18, 18, .11), transparent 28rem),
        linear-gradient(180deg, #fff, #f7faff);
    }
    .contact-grid {
      display: grid;
      grid-template-columns: minmax(0, .92fr) minmax(320px, 1fr);
      gap: clamp(1.5rem, 4vw, 3rem);
      align-items: start;
    }
    .email-link {
      display: inline-flex;
      color: var(--blue);
      font-size: clamp(1.65rem, 3.4vw, 3.2rem);
      font-weight: 950;
      letter-spacing: -.05em;
      text-decoration: none;
      margin: .55rem 0 1rem;
      word-break: break-word;
    }
    .contact-card {
      background: #fff;
      box-shadow: var(--shadow);
    }
    .contact-card label {
      display: block;
      margin: .95rem 0 .35rem;
      color: var(--navy);
      font-weight: 850;
      font-size: .92rem;
    }
    .contact-card input,
    .contact-card textarea,
    .contact-card select {
      width: 100%;
      border: 1px solid rgba(0, 58, 140, .2);
      border-radius: 16px;
      padding: .9rem 1rem;
      color: var(--ink);
      background: var(--soft);
      font: inherit;
    }
    .contact-card textarea { min-height: 138px; resize: vertical; }
    .contact-card .button { margin-top: 1rem; width: 100%; }
    .copy-status {
      display: inline-block;
      min-height: 1.4rem;
      margin-left: .75rem;
      color: var(--red-2);
      font-weight: 850;
      font-size: .92rem;
    }
    .footer {
      border-top: 1px solid var(--line);
      padding: 1.4rem 0;
      color: var(--muted);
      font-size: .92rem;
      background: #fff;
    }
    .footer .container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      gap: 1rem;
      flex-wrap: wrap;
    }

    .reveal {
      opacity: 0;
      transform: translateY(18px);
      transition: opacity .65s ease, transform .65s ease;
    }
    .reveal.visible {
      opacity: 1;
      transform: none;
    }

    @media (max-width: 980px) {
      .two-col, .contact-grid { grid-template-columns: 1fr; }
      .tool-grid, .application-grid, .origin-cards, .screenshot-grid, .people-grid, .named-people { grid-template-columns: repeat(2, minmax(0, 1fr)); }
      .program-highlight, .people-feature, .profile-card { grid-template-columns: 1fr; }
      .math-grid { grid-template-columns: 1fr; }
      .method-strip { grid-template-columns: repeat(2, minmax(0, 1fr)); }
      .hero { min-height: auto; }
      .hero-side { max-width: 720px; padding-top: 0; }
      .analysis-panel { max-width: 720px; }
    }

    @media (max-width: 1600px) {
      .nav-toggle { display: block; }
      .main-nav {
        position: absolute;
        left: 16px;
        right: 16px;
        top: 76px;
        display: none;
        flex-direction: column;
        align-items: stretch;
        background: #fff;
        border: 1px solid var(--line);
        border-radius: 20px;
        padding: .75rem;
        box-shadow: var(--shadow);
      }
      .main-nav.open { display: flex; }
      .main-nav a { text-align: center; white-space: normal; }
      .brand span { display: none; }
    }

    @media (max-width: 760px) {
      .metrics, .origin-cards, .tool-grid, .application-grid, .method-strip, .eq-grid, .screenshot-grid, .people-grid, .named-people { grid-template-columns: 1fr; }
      .program-highlight, .people-feature, .profile-card { grid-template-columns: 1fr; }
      h1 { font-size: clamp(2.55rem, 16vw, 4.2rem); }
      .section { padding: 3.8rem 0; }
      .panel-head { align-items: flex-start; }
      .footer .container { display: block; }
    }

    @media (prefers-reduced-motion: reduce) {
      html { scroll-behavior: auto; }
      *, *::before, *::after { animation: none !important; transition: none !important; }
      .reveal { opacity: 1; transform: none; }
    }

/* ── Aircraft Fuselage Stresses — interactive slider tool (aerospace.html) ── */
.fs-tool {
  margin-top: 1.6rem;
  padding: 1.6rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, rgba(255,255,255,.97), rgba(245,248,255,.97));
  box-shadow: 0 18px 46px rgba(6, 27, 59, .08);
}
.fs-tool-kicker {
  font-weight: 900;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: .06em;
  font-size: .82rem;
  margin-bottom: 1rem;
}
.fs-units-row {
  display: flex;
  flex-wrap: wrap;
  gap: 1.2rem;
  align-items: center;
  margin-bottom: 1.2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}
.fs-unit-select {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-size: .8rem;
  font-weight: 800;
  color: var(--navy);
  text-transform: uppercase;
  letter-spacing: .03em;
}
.fs-unit-select select {
  font: inherit;
  font-weight: 700;
  text-transform: none;
  letter-spacing: normal;
  color: var(--blue);
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: .35rem .9rem;
  cursor: pointer;
}
.fs-tool-visuals-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.4rem;
  margin-bottom: 1.2rem;
}
.fs-visual-block {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: .9rem;
  display: flex;
  flex-direction: column;
}
.fs-visual-label {
  display: block;
  font-size: .74rem;
  font-weight: 800;
  color: var(--blue);
  text-transform: uppercase;
  letter-spacing: .04em;
  margin-bottom: .6rem;
}
.fs-visual-block canvas {
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 1;
  border-radius: 8px;
  display: block;
}
.fs-visual-block svg {
  width: 100%;
  height: auto;
  display: block;
}
.fs-slider {
  display: flex;
  flex-direction: column;
  gap: .35rem;
  font-size: .84rem;
  color: var(--navy);
  font-weight: 700;
}
.fs-visual-block .fs-slider {
  margin-top: .9rem;
  padding-top: .8rem;
  border-top: 1px dashed var(--line);
}
.fs-slider-alt {
  max-width: 420px;
  margin: 0 auto 1.2rem;
  text-align: center;
}
.fs-slider input[type="range"] {
  width: 100%;
  accent-color: var(--blue);
}
.fs-slider strong {
  font-size: 1.05rem;
  color: var(--blue);
}
.fs-readouts {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: .5rem 1.5rem;
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
}
.fs-readouts div {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: .6rem;
  font-size: .86rem;
  color: var(--muted);
}
.fs-readouts strong {
  color: var(--navy);
  font-weight: 900;
  white-space: nowrap;
}
.fs-tool-note {
  margin-top: 1.1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: .82rem;
}