@media (max-width: 1280px) {
  :root {
    --shell: 1160px;
  }

  .shell {
    width: min(calc(100% - 64px), var(--shell));
  }

  .site-header {
    gap: 24px;
    padding-inline: 30px;
  }

  .brand {
    width: 174px;
  }

  .desktop-nav {
    gap: 24px;
  }

  .hero h1 {
    font-size: 72px;
  }

  .section-intro h2,
  .section-heading h2,
  .coordination-heading h2,
  .platform-copy h2,
  .assessment-copy h2 {
    font-size: 48px;
  }

  .why-layout,
  .process-layout {
    gap: 58px;
  }

  .decision-row {
    grid-template-columns: 54px 1fr 160px;
  }

  .capability-stage {
    grid-template-columns: 190px 1fr;
    gap: 34px;
  }

  .capability-panel {
    min-height: 430px;
    gap: 36px;
    padding: 38px;
  }

  .chapter-number {
    top: -174px;
    font-size: 148px;
  }

  .platform-layout {
    gap: 58px;
  }

  .assessment-layout {
    gap: 58px;
  }
}

@media (max-width: 1080px) {
  .site-header {
    grid-template-columns: 1fr auto auto;
  }

  .desktop-nav {
    display: none;
  }

  .menu-button {
    position: relative;
    z-index: 102;
    display: grid;
    width: 44px;
    height: 44px;
    place-content: center;
    gap: 7px;
    border: 1px solid var(--line);
    border-radius: 4px;
    background: rgba(255, 255, 255, 0.72);
    cursor: pointer;
  }

  .menu-button span {
    display: block;
    width: 18px;
    height: 1px;
    background: var(--ink);
    transition: transform 220ms var(--ease);
  }

  .menu-button.is-open span:first-child {
    transform: translateY(4px) rotate(45deg);
  }

  .menu-button.is-open span:last-child {
    transform: translateY(-4px) rotate(-45deg);
  }

  .mobile-menu {
    position: fixed;
    z-index: 101;
    inset: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--paper);
    backdrop-filter: blur(20px);
  }

  .mobile-menu nav {
    display: flex;
    width: min(calc(100% - 64px), 560px);
    flex-direction: column;
    align-items: stretch;
  }

  .mobile-menu nav > a {
    display: flex;
    min-height: 68px;
    align-items: center;
    justify-content: space-between;
    border-bottom: 1px solid var(--line);
    font-size: 22px;
    font-weight: 680;
  }

  .mobile-menu nav > a::after {
    color: var(--brand);
    content: "→";
    font-size: 18px;
  }

  .mobile-menu .mobile-menu-cta {
    justify-content: center;
    margin-top: 28px;
    border: 0;
    border-radius: 4px;
    background: var(--brand);
    color: var(--white);
    font-size: 15px;
  }

  .mobile-menu .mobile-menu-cta::after {
    display: none;
  }

  .hero-copy {
    width: 54%;
  }

  .hero-scene {
    width: 62%;
  }

  .why-layout,
  .process-layout {
    grid-template-columns: 1fr;
  }

  .sticky-intro,
  .capability-index {
    position: static;
  }

  .section-intro {
    max-width: 700px;
    margin-bottom: 52px;
  }

  .capability-stage {
    grid-template-columns: 1fr;
  }

  .capability-index {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    border-top: 1px solid var(--line);
  }

  .capability-index a {
    padding-inline: 16px;
    border-right: 1px solid var(--line);
  }

  .capability-index a:last-child {
    border-right: 0;
  }

  .capability-index a:hover,
  .capability-index a.is-active {
    padding-left: 22px;
  }

  .platform-layout,
  .assessment-layout {
    grid-template-columns: 1fr;
  }

  .platform-copy,
  .assessment-copy {
    max-width: 720px;
  }

  .platform-proof {
    min-height: 420px;
  }

  .assessment-copy ul {
    max-width: 640px;
  }
}

@media (max-width: 900px) {
  :root {
    --header-height: 72px;
  }

  .section {
    padding-block: 90px;
  }

  .hero {
    height: calc(100svh - 22px);
    min-height: 760px;
    max-height: none;
  }

  .hero::before {
    width: 100%;
    height: 66%;
    background: linear-gradient(180deg, var(--paper) 0%, var(--paper) 74%, rgba(245, 244, 240, 0) 100%);
  }

  .hero-content {
    align-items: flex-start;
    padding-top: 142px;
    padding-bottom: 260px;
  }

  .hero-copy {
    width: 72%;
  }

  .hero h1 {
    font-size: 62px;
  }

  .hero-summary {
    max-width: 520px;
    font-size: 17px;
  }

  .hero-scene {
    top: 46%;
    width: 100%;
    height: 54%;
  }

  .scene-wing {
    top: 7%;
    bottom: 18%;
  }

  .scene-star {
    top: 30%;
  }

  .scene-floor {
    bottom: -28%;
    height: 67%;
  }

  .proof-inner {
    min-height: 70px;
  }

  .section-heading,
  .coordination-heading {
    grid-template-columns: 1fr;
    margin-bottom: 52px;
  }

  .section-heading > p:last-child,
  .coordination-heading > p:last-child {
    max-width: 640px;
    margin-top: 28px;
  }

  .capability-panel {
    min-height: 490px;
    grid-template-columns: 1fr;
    align-items: end;
  }

  .capability-title {
    align-self: end;
  }

  .chapter-number {
    top: -150px;
    font-size: 132px;
  }

  .capability-result {
    align-self: end;
  }

  .decision-row {
    grid-template-columns: 54px 1fr;
  }

  .decision-row strong {
    grid-column: 2;
    align-self: start;
    text-align: left;
  }

  .why-conclusion {
    padding-left: 0;
  }

  .handoff-row {
    grid-template-columns: 70px 0.8fr 1.2fr;
  }

  .single-owner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer-main,
  .footer-legal {
    grid-template-columns: 1fr;
  }

  .footer-links {
    justify-content: flex-start;
  }

  .footer-legal {
    gap: 24px;
  }
}

@media (max-width: 640px) {
  .shell {
    width: calc(100% - 36px);
  }

  .section {
    padding-block: 68px;
  }

  .site-header,
  .site-header.is-scrolled {
    height: 68px;
    grid-template-columns: 1fr auto;
    gap: 12px;
    padding-inline: 18px;
  }

  .brand {
    width: 154px;
    height: 34px;
  }

  .header-cta {
    display: none;
  }

  .mobile-menu nav {
    width: calc(100% - 36px);
  }

  .mobile-menu nav > a {
    min-height: 62px;
    font-size: 20px;
  }

  .hero {
    height: calc(100svh - 18px);
    min-height: 620px;
  }

  .hero-content {
    padding-top: 104px;
    padding-bottom: 236px;
  }

  .hero-copy {
    width: 100%;
  }

  .hero-copy .eyebrow {
    margin-bottom: 18px;
    font-size: 10px;
  }

  .hero h1 {
    max-width: 440px;
    font-size: 47px;
    line-height: 1.08;
  }

  .hero-summary {
    max-width: 390px;
    margin-top: 18px;
    font-size: 15px;
    line-height: 1.7;
  }

  .hero-actions {
    gap: 20px;
    margin-top: 24px;
  }

  .hero-actions .button {
    min-height: 48px;
    padding-inline: 18px;
    font-size: 13px;
  }

  .hero-actions .text-link {
    font-size: 13px;
  }

  .hero-scene {
    top: 53%;
    height: 47%;
  }

  .scene-wing {
    top: 12%;
    bottom: 22%;
  }

  .scene-wing-left {
    left: -5%;
  }

  .scene-wing-right {
    right: -16%;
  }

  .scene-opening {
    top: 9%;
    bottom: 18%;
  }

  .scene-star {
    top: 31%;
    width: 20px;
    height: 20px;
  }

  .scene-star::before {
    height: 34px;
  }

  .scene-star::after {
    width: 34px;
  }

  .scene-star span::after {
    width: 58px;
    height: 58px;
  }

  .scene-path {
    right: 11%;
    height: 42%;
  }

  .hero-proof {
    background: rgba(245, 244, 240, 0.9);
  }

  .proof-inner {
    width: calc(100% - 24px);
    min-height: 62px;
    grid-template-columns: 0.9fr 1.25fr 1.2fr;
  }

  .proof-inner span,
  .proof-inner span + span {
    display: flex;
    min-height: 62px;
    align-items: center;
    padding: 0 7px;
    font-size: 10px;
    line-height: 1.35;
    text-align: center;
  }

  .proof-inner span::before,
  .proof-inner span + span::before {
    display: none;
  }

  .scroll-cue {
    display: none;
  }

  .section-intro h2,
  .section-heading h2,
  .coordination-heading h2,
  .platform-copy h2,
  .assessment-copy h2 {
    font-size: 36px;
    line-height: 1.18;
  }

  .section-intro > p:last-child,
  .section-heading > p:last-child,
  .coordination-heading > p:last-child,
  .platform-copy > p,
  .assessment-copy > p {
    margin-top: 18px;
    font-size: 14px;
    line-height: 1.65;
  }

  .why-layout,
  .process-layout {
    gap: 0;
  }

  .section-intro {
    margin-bottom: 40px;
  }

  .decision-row {
    min-height: 0;
    grid-template-columns: 36px 1fr;
    gap: 14px;
    padding-block: 30px;
  }

  .decision-row h3 {
    font-size: 21px;
  }

  .decision-row p {
    margin-top: 12px;
    font-size: 14px;
  }

  .decision-row strong {
    font-size: 12px;
  }

  .why-conclusion {
    margin-top: 38px;
    font-size: 22px;
  }

  .section-heading,
  .coordination-heading {
    margin-bottom: 40px;
  }

  .capability-stage {
    gap: 22px;
  }

  .capability-index {
    position: sticky;
    z-index: 20;
    top: 68px;
    margin-inline: -18px;
    border-bottom: 1px solid var(--line);
    background: rgba(251, 250, 247, 0.94);
    backdrop-filter: blur(12px);
  }

  .capability-index a {
    min-height: 54px;
    grid-template-columns: 1fr;
    place-items: center;
    padding: 6px;
    border-bottom: 0;
    font-size: 11px;
    text-align: center;
  }

  .capability-index a span {
    display: none;
  }

  .capability-index a:hover,
  .capability-index a.is-active {
    padding-left: 6px;
    background: rgba(11, 73, 161, 0.07);
  }

  .capability-panels {
    gap: 18px;
  }

  .capability-panel {
    min-height: 470px;
    gap: 28px;
    padding: 28px 24px;
  }

  .capability-panel::before {
    right: -35%;
    width: 70%;
  }

  .chapter-number {
    top: -108px;
    left: -4px;
    font-size: 100px;
  }

  .capability-title h3 {
    font-size: 30px;
  }

  .capability-title > p:last-child {
    margin-top: 18px;
    font-size: 14px;
  }

  .capability-result li {
    min-height: 68px;
  }

  .handoff-row {
    min-height: 112px;
    grid-template-columns: 38px 1fr;
    gap: 8px 12px;
    padding-block: 22px;
  }

  .handoff-row h3 {
    font-size: 23px;
  }

  .handoff-row p {
    grid-column: 2;
    font-size: 13px;
  }

  .single-owner {
    margin-top: 52px;
    padding-block: 30px;
  }

  .single-owner > p {
    font-size: 22px;
  }

  .single-owner > div {
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .platform-layout,
  .assessment-layout {
    gap: 52px;
  }

  .platform-proof {
    min-height: 400px;
    padding: 34px 26px;
  }

  .platform-mark span,
  .platform-mark strong {
    font-size: 39px;
  }

  .platform-proof dl > div {
    min-height: 82px;
    grid-template-columns: 98px 1fr;
    gap: 14px;
  }

  .platform-proof dd {
    font-size: 12px;
  }

  .process-step {
    min-height: 0;
    grid-template-columns: 38px 1fr;
    gap: 14px;
    padding-block: 22px;
  }

  .process-step h3 {
    font-size: 23px;
  }

  .process-note {
    margin-top: 48px;
  }

  .assessment-form-wrap {
    min-height: 0;
  }

  .assessment-form {
    padding: 26px 20px;
  }

  .stage-options,
  .form-grid {
    grid-template-columns: 1fr;
  }

  .stage-options span {
    min-height: 58px;
  }

  .form-grid {
    gap: 18px;
  }

  .form-footer {
    flex-direction: column;
    align-items: stretch;
  }

  .form-footer .button {
    width: 100%;
  }

  .form-success {
    min-height: 580px;
    padding: 42px 26px;
  }

  .form-success h3 {
    font-size: 32px;
  }

  .site-footer {
    padding-top: 64px;
    padding-bottom: 96px;
  }

  .footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
  }

  .footer-legal {
    margin-top: 48px;
  }

  .mobile-sticky-cta {
    position: fixed;
    z-index: 90;
    right: 10px;
    bottom: calc(10px + env(safe-area-inset-bottom));
    left: 10px;
    display: flex;
    min-height: 64px;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 8px 8px 8px 16px;
    transform: translateY(130%);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: 6px;
    background: rgba(16, 19, 24, 0.94);
    color: var(--white);
    box-shadow: 0 16px 38px rgba(0, 0, 0, 0.24);
    backdrop-filter: blur(18px);
    transition: transform 280ms var(--ease);
  }

  .mobile-sticky-cta.is-visible {
    transform: translateY(0);
  }

  .mobile-sticky-cta span {
    font-size: 11px;
    line-height: 1.35;
  }

  .mobile-sticky-cta .button {
    min-height: 46px;
    flex: 0 0 auto;
    padding-inline: 16px;
    font-size: 12px;
  }
}

@media (max-width: 380px) {
  .hero h1 {
    font-size: 42px;
  }

  .hero-summary {
    font-size: 14px;
  }

  .hero-actions {
    gap: 14px;
  }

  .hero-actions .button {
    padding-inline: 14px;
  }

  .section-intro h2,
  .section-heading h2,
  .coordination-heading h2,
  .platform-copy h2,
  .assessment-copy h2 {
    font-size: 36px;
  }
}