:root {
  --paper: #f2eee4;
  --paper-light: #fbf9f3;
  --ink: #121413;
  --ink-soft: #555c59;
  --blue: #17384a;
  --blue-mid: #2b5b6e;
  --blue-pale: #d8e3e5;
  --amber: #b97627;
  --line: rgba(23, 56, 74, 0.22);
  --line-light: rgba(242, 238, 228, 0.24);
  --display: "Bodoni Moda", Didot, "Times New Roman", serif;
  --sans: "Manrope", Arial, sans-serif;
  --page: min(100% - 80px, 1440px);
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scrollbar-color: var(--amber) var(--blue);
  scrollbar-width: thin;
}

body {
  margin: 0;
  overflow-x: hidden;
  color: var(--ink);
  background: var(--paper);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: 100;
  box-shadow: inset 0 0 0 1px rgba(18, 20, 19, 0.07);
  content: "";
  pointer-events: none;
}

::selection {
  color: var(--paper-light);
  background: var(--blue-mid);
}

::-webkit-scrollbar {
  width: 9px;
}

::-webkit-scrollbar-track {
  background: var(--blue);
}

::-webkit-scrollbar-thumb {
  border: 2px solid var(--blue);
  background: var(--amber);
}

a {
  color: inherit;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.24em;
}

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 5px;
}

h1,
h2,
h3,
p,
figure,
blockquote,
dl,
dd,
ol,
ul {
  margin-top: 0;
}

h1,
h2,
h3 {
  font-family: var(--display);
  font-weight: 400;
  letter-spacing: -0.035em;
  line-height: 0.98;
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

.skip-link {
  position: fixed;
  top: 12px;
  left: 12px;
  z-index: 999;
  padding: 12px 18px;
  color: var(--paper-light);
  background: var(--blue);
  font-size: 0.84rem;
  font-weight: 700;
  transform: translateY(-160%);
  transition: transform 180ms ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  display: grid;
  min-height: 78px;
  grid-template-columns: auto 1fr;
  align-items: center;
  padding: 10px max(40px, calc((100% - 1440px) / 2));
  border-bottom: 1px solid var(--line);
  background: rgba(242, 238, 228, 0.98);
  transition: min-height 260ms var(--ease), box-shadow 260ms var(--ease);
}

.site-header.is-scrolled {
  min-height: 70px;
  box-shadow: 0 16px 38px rgba(18, 20, 19, 0.08);
}

.brand {
  display: flex;
  width: max-content;
  align-items: center;
  color: var(--blue);
  line-height: 1;
  text-decoration: none;
}

.brand-mark {
  padding-right: 18px;
  border-right: 1px solid var(--line);
  font-family: var(--display);
  font-size: 2rem;
  letter-spacing: -0.03em;
}

.brand-copy {
  display: grid;
  padding-left: 18px;
  gap: 6px;
}

.brand-copy strong,
.brand-copy small {
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.brand-copy small {
  color: var(--ink-soft);
  font-size: 0.55rem;
  letter-spacing: 0.2em;
}

.site-nav {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: clamp(16px, 1.8vw, 32px);
}

.site-nav a {
  position: relative;
  font-size: 0.7rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-decoration: none;
  text-transform: uppercase;
}

.site-nav > a:not(.nav-cta)::after {
  position: absolute;
  right: 0;
  bottom: -6px;
  left: 0;
  height: 1px;
  background: var(--amber);
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 220ms var(--ease);
}

.site-nav > a:not(.nav-cta):hover::after,
.site-nav > a:not(.nav-cta):focus-visible::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-cta,
.button {
  display: inline-flex;
  min-height: 52px;
  align-items: center;
  justify-content: center;
  padding: 14px 24px;
  border: 1px solid transparent;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.075em;
  line-height: 1.2;
  text-align: center;
  text-decoration: none;
  text-transform: uppercase;
  transition: color 220ms ease, background 220ms ease, border-color 220ms ease, transform 220ms var(--ease);
}

.nav-cta,
.button-dark {
  color: var(--paper-light);
  background: var(--blue);
}

.nav-cta:hover,
.button-dark:hover {
  border-color: var(--blue);
  color: var(--blue);
  background: transparent;
  transform: translateY(-2px);
}

.button-amber {
  color: var(--blue);
  background: var(--amber);
}

.button-amber:hover {
  border-color: var(--paper-light);
  color: var(--paper-light);
  background: transparent;
  transform: translateY(-2px);
}

.menu-button {
  display: none;
}

.hero-thesis {
  display: grid;
  width: var(--page);
  min-height: 286px;
  margin: 0 auto;
  grid-template-columns: minmax(0, 2.15fr) minmax(270px, 0.75fr);
  align-items: end;
  gap: clamp(50px, 8vw, 140px);
  padding: clamp(40px, 5vw, 64px) 0 38px;
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 28px;
  color: var(--blue-mid);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  text-transform: uppercase;
}

.breadcrumb a {
  text-decoration: none;
}

.hero h1 {
  max-width: 920px;
  margin-bottom: 0;
  font-size: clamp(4.2rem, 6.4vw, 5.8rem);
  line-height: 0.93;
}

.hero-intro {
  max-width: 420px;
  padding-bottom: 6px;
}

.hero-intro p {
  margin-bottom: 28px;
  color: var(--ink-soft);
  font-size: clamp(1rem, 1.2vw, 1.17rem);
  line-height: 1.65;
}

.strata-stage {
  display: grid;
  min-height: 344px;
  grid-template-columns: minmax(300px, 26%) minmax(0, 1fr);
  border-top: 1px solid rgba(18, 20, 19, 0.04);
  background: var(--paper-light);
}

.strata-key {
  display: grid;
  margin: 0;
  padding: 34px 28px 34px max(40px, calc((100vw - 1440px) / 2));
  grid-template-rows: 0.9fr 1fr 0.75fr 1.35fr;
  list-style: none;
}

.strata-key li {
  display: grid;
  grid-template-columns: max-content minmax(36px, 1fr);
  align-items: center;
  gap: 16px;
  color: var(--blue);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.07em;
  line-height: 1.25;
  text-transform: uppercase;
}

.strata-key li::after {
  height: 1px;
  background: var(--line);
  content: "";
}

.strata-key .is-margin {
  color: var(--amber);
}

.strata-key .is-margin::after {
  background: var(--amber);
}

.strata-art {
  position: relative;
  min-width: 0;
  height: 344px;
  margin: 0;
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  overflow: hidden;
}

.strata-art img {
  height: 100%;
  object-fit: cover;
  object-position: 50% 51%;
}

.strata-art figcaption,
.margin-art figcaption,
.materials-art figcaption {
  position: static;
  max-width: none;
  margin: 0;
  padding: 7px 14px;
  color: rgba(18, 20, 19, 0.74);
  background: var(--paper-light);
  font-size: 0.64rem;
  line-height: 1.35;
  text-align: right;
}

.margin-trace {
  position: absolute;
  top: 51.5%;
  right: 0;
  left: 0;
  height: 1px;
  background: var(--amber);
  transform-origin: left;
  transition: transform 1100ms var(--ease), opacity 600ms ease;
}

.margin-trace::after {
  position: absolute;
  top: -5px;
  left: 56%;
  width: 11px;
  height: 11px;
  border: 2px solid var(--paper-light);
  border-radius: 50%;
  background: var(--amber);
  box-shadow: 0 3px 12px rgba(18, 20, 19, 0.22);
  content: "";
}

.js .margin-trace {
  opacity: 0.55;
  transform: scaleX(0.16);
}

.js.is-ready .margin-trace {
  opacity: 1;
  transform: scaleX(1);
}

.decisions {
  padding: clamp(60px, 6vw, 88px) max(40px, calc((100% - 1440px) / 2)) clamp(70px, 7vw, 104px);
  color: var(--paper-light);
  background: var(--blue);
}

.decisions-header {
  display: grid;
  max-width: 1280px;
  grid-template-columns: minmax(0, 1.3fr) minmax(280px, 0.7fr);
  align-items: end;
  gap: 80px;
}

.decisions h2 {
  max-width: 760px;
  margin-bottom: 0;
  font-size: clamp(3.25rem, 5vw, 5.2rem);
}

.decisions-header p {
  max-width: 470px;
  margin-bottom: 5px;
  color: var(--blue-pale);
}

.decision-track {
  position: relative;
  display: grid;
  max-width: 1440px;
  margin: clamp(54px, 6vw, 86px) 0 0;
  padding: 0;
  grid-template-columns: repeat(4, 1fr);
  list-style: none;
}

.decision-track::before {
  position: absolute;
  top: 18px;
  right: 3%;
  left: 3%;
  height: 1px;
  background: rgba(242, 238, 228, 0.62);
  content: "";
}

.decision-track li {
  position: relative;
  min-height: 190px;
  padding: 56px clamp(18px, 2vw, 34px) 0;
  border-right: 1px solid var(--line-light);
}

.decision-track li:last-child {
  border-right: 0;
}

.decision-track span {
  position: absolute;
  top: 0;
  left: clamp(18px, 2vw, 34px);
  z-index: 1;
  display: grid;
  width: 37px;
  height: 37px;
  place-items: center;
  border: 1px solid rgba(242, 238, 228, 0.76);
  border-radius: 50%;
  color: var(--paper-light);
  background: var(--blue);
  font-family: var(--display);
  font-size: 0.9rem;
  font-variant-numeric: tabular-nums;
}

.decision-track li:nth-child(3) span {
  color: var(--blue);
  border-color: var(--amber);
  background: var(--amber);
}

.decision-track h3 {
  margin-bottom: 14px;
  font-family: var(--sans);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  line-height: 1.25;
  text-transform: uppercase;
}

.decision-track p {
  max-width: 30ch;
  margin-bottom: 0;
  color: var(--blue-pale);
  font-size: 0.9rem;
  line-height: 1.55;
}

.evaluation {
  padding: clamp(90px, 10vw, 160px) 0 0;
  background: var(--paper);
}

.evaluation-heading {
  display: grid;
  width: var(--page);
  margin: 0 auto clamp(54px, 7vw, 96px);
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.75fr);
  align-items: end;
  gap: 90px;
}

.evaluation-heading h2,
.preserve h2,
.metal h2,
.materials h2,
.process h2,
.expectations h2,
.faq h2,
.final-cta h2 {
  margin-bottom: 0;
  font-size: clamp(3.4rem, 5.5vw, 5.8rem);
}

.evaluation-heading p {
  max-width: 58ch;
  margin-bottom: 6px;
  color: var(--ink-soft);
}

.margin-art {
  position: relative;
  width: min(100% - 80px, 1440px);
  height: clamp(420px, 52vw, 720px);
  margin: 0 auto;
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  overflow: hidden;
  background: var(--paper-light);
}

.margin-art img {
  height: 100%;
  object-fit: cover;
}

.margin-art > i {
  position: absolute;
  top: 49%;
  right: 6%;
  left: 7%;
  height: 1px;
  background: var(--amber);
  transform: rotate(-25.5deg);
  transform-origin: center;
}

.margin-art > i::after {
  position: absolute;
  top: -5px;
  left: 50%;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber);
  content: "";
}

.signals {
  display: grid;
  width: var(--page);
  margin: 0 auto;
  grid-template-columns: repeat(4, 1fr);
}

.signals article {
  min-height: 230px;
  padding: 42px 30px 56px;
  border-right: 1px solid var(--line);
}

.signals article:first-child {
  padding-left: 0;
}

.signals article:last-child {
  padding-right: 0;
  border-right: 0;
}

.signals h3 {
  margin-bottom: 18px;
  font-size: clamp(1.9rem, 2.4vw, 2.7rem);
}

.signals p {
  margin-bottom: 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.preserve {
  display: grid;
  padding: clamp(90px, 9vw, 150px) max(40px, calc((100% - 1440px) / 2));
  grid-template-columns: minmax(0, 1.2fr) minmax(320px, 0.8fr);
  gap: clamp(60px, 10vw, 180px);
  color: var(--paper-light);
  background: var(--blue);
}

.preserve-copy {
  max-width: 640px;
}

.preserve-copy p {
  color: var(--blue-pale);
  font-size: clamp(1rem, 1.2vw, 1.15rem);
}

.preserve-copy p:last-child {
  margin-bottom: 0;
}

.metal {
  position: relative;
  display: grid;
  width: var(--page);
  margin: 0 auto;
  padding: clamp(110px, 12vw, 190px) 0;
  grid-template-columns: minmax(0, 1.25fr) minmax(260px, 0.55fr);
  gap: clamp(60px, 9vw, 150px);
}

.metal-line {
  position: absolute;
  top: 84px;
  right: 0;
  left: 0;
  height: 1px;
  background: var(--line);
}

.metal-line i {
  position: absolute;
  top: -5px;
  left: 64%;
  width: 11px;
  height: 11px;
  border-radius: 50%;
  background: var(--amber);
}

.metal-copy h2 {
  max-width: 920px;
  margin-bottom: 40px;
}

.metal-copy p {
  max-width: 70ch;
  color: var(--ink-soft);
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-top: 12px;
  color: var(--blue);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.text-link::after {
  content: "→";
  font-size: 1.15rem;
}

.metal-note {
  align-self: end;
  padding: 28px 0 0;
  border-top: 1px solid var(--amber);
}

.metal-note strong,
.metal-note span {
  display: block;
}

.metal-note strong {
  margin-bottom: 12px;
  font-family: var(--display);
  font-size: 2rem;
  font-weight: 400;
  line-height: 1.05;
}

.metal-note span {
  color: var(--ink-soft);
}

.materials {
  display: grid;
  min-height: 760px;
  grid-template-columns: minmax(420px, 0.88fr) minmax(0, 1.12fr);
  color: var(--paper-light);
  background: var(--blue);
}

.materials-copy {
  align-self: center;
  max-width: 720px;
  padding: clamp(70px, 8vw, 130px) clamp(40px, 6vw, 100px) clamp(70px, 8vw, 130px) max(40px, calc((100vw - 1440px) / 2));
}

.materials-copy h2 {
  margin-bottom: 38px;
}

.materials-copy > p {
  max-width: 62ch;
  color: var(--blue-pale);
}

.material-types {
  margin: 50px 0 0;
  border-top: 1px solid var(--line-light);
}

.material-types div {
  display: grid;
  padding: 25px 0;
  grid-template-columns: 180px 1fr;
  gap: 30px;
  border-bottom: 1px solid var(--line-light);
}

.material-types dt {
  font-family: var(--display);
  font-size: 1.55rem;
  line-height: 1.05;
}

.material-types dd {
  color: var(--blue-pale);
  font-size: 0.9rem;
  line-height: 1.55;
}

.materials-art {
  position: relative;
  min-height: 760px;
  margin: 0;
  display: grid;
  grid-template-rows: minmax(0, 1fr) auto;
  overflow: hidden;
}

.materials-art img {
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.materials-art figcaption {
  color: var(--blue-pale);
  background: var(--blue);
}

.process {
  width: var(--page);
  margin: 0 auto;
  padding: clamp(100px, 11vw, 180px) 0;
}

.process-heading {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.6fr);
  align-items: end;
  gap: 90px;
}

.process-heading p {
  max-width: 52ch;
  margin-bottom: 5px;
  color: var(--ink-soft);
}

.process-list {
  margin: clamp(60px, 7vw, 100px) 0 0;
  padding: 0;
  border-top: 1px solid var(--line);
  list-style: none;
}

.process-list li {
  display: grid;
  min-height: 148px;
  padding: 30px 0;
  grid-template-columns: 120px 1fr;
  align-items: center;
  border-bottom: 1px solid var(--line);
}

.process-list > li > span {
  color: var(--amber);
  font-family: var(--display);
  font-size: 2rem;
  font-variant-numeric: tabular-nums;
}

.process-list div {
  display: grid;
  grid-template-columns: minmax(250px, 0.65fr) minmax(300px, 1fr);
  align-items: center;
  gap: 60px;
}

.process-list h3 {
  margin-bottom: 0;
  font-size: clamp(2rem, 2.7vw, 3rem);
}

.process-list p {
  max-width: 65ch;
  margin-bottom: 0;
  color: var(--ink-soft);
}

.expectations {
  display: grid;
  padding: clamp(95px, 10vw, 160px) max(40px, calc((100% - 1440px) / 2));
  grid-template-columns: minmax(0, 1.15fr) minmax(320px, 0.7fr);
  gap: clamp(60px, 10vw, 170px);
  background: var(--paper-light);
}

.expectations div {
  max-width: 620px;
}

.expectations p {
  color: var(--ink-soft);
}

.expectations p:last-child {
  margin-bottom: 0;
}

.faq {
  display: grid;
  padding: clamp(100px, 11vw, 180px) max(40px, calc((100% - 1440px) / 2));
  grid-template-columns: minmax(300px, 0.68fr) minmax(420px, 1fr);
  gap: clamp(70px, 11vw, 190px);
  color: var(--paper-light);
  background: var(--blue);
}

.faq-heading {
  align-self: start;
}

.faq-heading h2 {
  margin-bottom: 36px;
}

.faq-heading p {
  max-width: 42ch;
  color: var(--blue-pale);
}

.faq-list {
  border-top: 1px solid var(--line-light);
}

.faq details {
  border-bottom: 1px solid var(--line-light);
}

.faq summary {
  position: relative;
  padding: 28px 52px 28px 0;
  cursor: pointer;
  font-family: var(--display);
  font-size: clamp(1.45rem, 2vw, 2.1rem);
  line-height: 1.1;
  list-style: none;
}

.faq summary::-webkit-details-marker {
  display: none;
}

.faq summary::before,
.faq summary::after {
  position: absolute;
  top: 50%;
  right: 2px;
  width: 22px;
  height: 1px;
  background: var(--amber);
  content: "";
  transition: transform 220ms ease;
}

.faq summary::after {
  transform: rotate(90deg);
}

.faq details[open] summary::after {
  transform: rotate(0deg);
}

.faq details p {
  max-width: 68ch;
  padding: 0 48px 26px 0;
  color: var(--blue-pale);
}

.references {
  padding: clamp(70px, 8vw, 120px) max(40px, calc((100% - 1440px) / 2));
  background: var(--paper-light);
}

.references h2 {
  margin-bottom: 22px;
  font-size: clamp(2.5rem, 3.8vw, 4rem);
}

.references > p {
  max-width: 76ch;
  color: var(--ink-soft);
}

.references ul {
  display: grid;
  margin: 42px 0 0;
  padding: 0;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 50px;
  border-top: 1px solid var(--line);
  list-style: none;
}

.references li {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.88rem;
}

.references a {
  color: var(--blue);
}

.final-cta {
  display: flex;
  min-height: 430px;
  align-items: center;
  justify-content: space-between;
  gap: 60px;
  padding: clamp(80px, 9vw, 150px) max(40px, calc((100% - 1440px) / 2));
  color: var(--paper-light);
  background: var(--blue);
}

.final-cta div {
  max-width: 850px;
}

.final-cta h2 {
  margin-bottom: 28px;
}

.final-cta p {
  max-width: 52ch;
  margin-bottom: 0;
  color: var(--blue-pale);
  font-size: 1.05rem;
}

.final-cta .button {
  flex: 0 0 auto;
}

.site-footer {
  display: grid;
  padding: 54px max(40px, calc((100% - 1440px) / 2));
  grid-template-columns: 1.1fr 0.8fr 1fr;
  align-items: end;
  gap: 50px;
  color: var(--blue-pale);
  background: var(--ink);
  font-size: 0.78rem;
}

.footer-brand {
  font-family: var(--display);
  font-size: 1.7rem;
  text-decoration: none;
}

.footer-brand span {
  display: block;
  margin-top: 8px;
  font-family: var(--sans);
  font-size: 0.58rem;
  font-weight: 700;
  letter-spacing: 0.18em;
  text-transform: uppercase;
}

.site-footer div {
  display: grid;
  gap: 8px;
}

.site-footer address {
  font-style: normal;
}

.site-footer small {
  grid-column: 1 / -1;
  padding-top: 28px;
  border-top: 1px solid rgba(216, 227, 229, 0.18);
  color: rgba(216, 227, 229, 0.66);
}

@media (max-width: 1180px) {
  :root {
    --page: min(100% - 56px, 1100px);
  }

  .site-header {
    padding-inline: 28px;
  }

  .site-nav {
    gap: 16px;
  }

  .site-nav > a:not(.nav-cta) {
    display: none;
  }

  .strata-stage {
    grid-template-columns: minmax(250px, 29%) minmax(0, 1fr);
  }

  .strata-key {
    padding-left: 28px;
  }

  .decision-track li {
    padding-inline: 18px;
  }

  .decision-track span {
    left: 18px;
  }

  .materials {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 860px) {
  :root {
    --page: min(100% - 40px, 720px);
  }

  body.menu-open {
    overflow: hidden;
  }

  .site-header {
    min-height: 72px;
    padding: 10px 20px;
  }

  .brand-mark {
    padding-right: 12px;
    font-size: 1.72rem;
  }

  .brand-copy {
    padding-left: 12px;
  }

  .brand-copy strong {
    font-size: 0.6rem;
  }

  .menu-button {
    display: grid;
    justify-self: end;
    width: 50px;
    height: 50px;
    place-items: center;
    border: 0;
    color: var(--paper-light);
    background: var(--blue);
    cursor: pointer;
  }

  .menu-button span {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
  }

  .menu-button i,
  .menu-button i::before,
  .menu-button i::after {
    display: block;
    width: 22px;
    height: 1px;
    background: currentColor;
    content: "";
    transition: transform 220ms ease, opacity 220ms ease;
  }

  .menu-button i::before {
    transform: translateY(-7px);
  }

  .menu-button i::after {
    transform: translateY(6px);
  }

  .menu-button[aria-expanded="true"] i {
    background: transparent;
  }

  .menu-button[aria-expanded="true"] i::before {
    transform: rotate(45deg);
  }

  .menu-button[aria-expanded="true"] i::after {
    transform: rotate(-45deg) translateY(-1px);
  }

  .site-nav {
    position: absolute;
    top: 72px;
    right: 0;
    left: 0;
    z-index: -1;
    display: grid;
    max-height: calc(100vh - 72px);
    padding: 28px 20px 34px;
    gap: 0;
    overflow-y: auto;
    border-bottom: 1px solid var(--line);
    background: var(--paper-light);
    box-shadow: 0 18px 36px rgba(18, 20, 19, 0.12);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-14px);
    transition: opacity 200ms ease, transform 280ms var(--ease);
  }

  .site-nav > a:not(.nav-cta) {
    display: block;
  }

  .site-nav a {
    padding: 17px 4px;
    border-bottom: 1px solid var(--line);
    font-size: 0.8rem;
  }

  .site-nav .nav-cta {
    margin-top: 24px;
    padding: 14px 22px;
    border-bottom: 1px solid transparent;
  }

  .site-nav.is-open {
    z-index: 1;
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
  }

  .hero-thesis,
  .decisions-header,
  .evaluation-heading,
  .preserve,
  .metal,
  .materials,
  .process-heading,
  .expectations,
  .faq {
    grid-template-columns: 1fr;
  }

  .hero-thesis {
    min-height: 0;
    align-items: start;
    gap: 34px;
    padding: 52px 0 48px;
  }

  .hero-break {
    display: none;
  }

  .breadcrumb {
    margin-bottom: 24px;
  }

  .hero h1 {
    max-width: 710px;
    font-size: clamp(3.65rem, 11.5vw, 5.3rem);
  }

  .hero-intro {
    max-width: 590px;
  }

  .strata-stage {
    display: block;
    min-height: 0;
  }

  .strata-key {
    width: var(--page);
    margin: 0 auto;
    padding: 26px 0;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    grid-template-rows: auto;
    gap: 14px 24px;
  }

  .strata-key li {
    grid-template-columns: max-content 1fr;
  }

  .strata-art {
    height: clamp(350px, 86vw, 560px);
  }

  .strata-art img {
    object-position: 55% center;
  }

  .strata-art figcaption,
  .margin-art figcaption,
  .materials-art figcaption {
    padding-inline: 12px;
  }

  .margin-trace {
    top: 51.8%;
  }

  .decisions {
    padding-inline: 20px;
  }

  .decisions-header {
    gap: 28px;
  }

  .decisions h2 {
    font-size: clamp(3.2rem, 10vw, 4.7rem);
  }

  .decision-track {
    display: block;
    margin-top: 56px;
    padding-left: 4px;
  }

  .decision-track::before {
    top: 18px;
    bottom: 18px;
    left: 22px;
    width: 1px;
    height: auto;
  }

  .decision-track li {
    min-height: 0;
    padding: 0 0 42px 68px;
    border-right: 0;
  }

  .decision-track li:last-child {
    padding-bottom: 0;
  }

  .decision-track span {
    left: 0;
  }

  .decision-track p {
    max-width: 52ch;
  }

  .evaluation-heading {
    gap: 30px;
  }

  .margin-art {
    width: 100%;
    height: clamp(410px, 82vw, 620px);
  }

  .signals {
    grid-template-columns: repeat(2, 1fr);
  }

  .signals article,
  .signals article:first-child,
  .signals article:last-child {
    min-height: 0;
    padding: 34px 24px 42px;
    border-right: 1px solid var(--line);
    border-bottom: 1px solid var(--line);
  }

  .signals article:nth-child(2n) {
    border-right: 0;
  }

  .preserve,
  .expectations,
  .faq {
    gap: 42px;
    padding-inline: 20px;
  }

  .metal {
    gap: 50px;
  }

  .metal-line {
    top: 70px;
  }

  .materials {
    min-height: 0;
  }

  .materials-copy {
    max-width: none;
    padding: 82px 20px 70px;
  }

  .materials-art {
    min-height: clamp(480px, 80vw, 680px);
  }

  .process-heading {
    gap: 32px;
  }

  .process-list div {
    min-width: 0;
    grid-template-columns: 1fr;
    gap: 14px;
  }

  .expectations div {
    max-width: 680px;
  }

  .faq-list {
    width: 100%;
  }

  .references {
    padding-inline: 20px;
  }

  .references ul {
    grid-template-columns: 1fr;
  }

  .final-cta {
    align-items: flex-start;
    flex-direction: column;
    padding-inline: 20px;
  }

  .site-footer {
    padding-inline: 20px;
    grid-template-columns: 1fr 1fr;
  }

  .site-footer address {
    grid-column: 1 / -1;
  }
}

@media (max-width: 520px) {
  :root {
    --page: calc(100% - 40px);
  }

  .brand-copy strong {
    max-width: 126px;
    line-height: 1.2;
  }

  .brand-copy small {
    display: none;
  }

  .hero h1,
  .evaluation-heading h2,
  .preserve h2,
  .metal h2,
  .materials h2,
  .process h2,
  .expectations h2,
  .faq h2,
  .final-cta h2 {
    font-size: clamp(3rem, 14vw, 4rem);
    line-height: 0.96;
  }

  .breadcrumb {
    font-size: 0.61rem;
  }

  .hero-intro .button {
    width: 100%;
  }

  .strata-key {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 14px 18px;
  }

  .strata-key li {
    min-width: 0;
    grid-template-columns: minmax(0, max-content) minmax(14px, 1fr);
    gap: 10px;
    font-size: 0.66rem;
  }

  .strata-art {
    height: 420px;
  }

  .strata-art img {
    object-position: 59% center;
  }

  .decisions {
    padding-top: 64px;
  }

  .decisions h2 {
    font-size: 3.25rem;
  }

  .evaluation {
    padding-top: 86px;
  }

  .margin-art {
    height: 470px;
  }

  .margin-art img {
    object-position: 48% center;
  }

  .signals {
    grid-template-columns: 1fr;
  }

  .signals article,
  .signals article:first-child,
  .signals article:last-child {
    padding-inline: 0;
    border-right: 0;
  }

  .preserve {
    padding-top: 86px;
    padding-bottom: 90px;
  }

  .metal {
    padding-top: 110px;
  }

  .metal-line {
    top: 68px;
  }

  .material-types div {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .materials-art {
    min-height: 520px;
  }

  .materials-art img {
    object-position: center;
  }

  .process-list li {
    grid-template-columns: 52px minmax(0, 1fr);
    align-items: start;
  }

  .process-list > li > span {
    font-size: 1.55rem;
  }

  .process-list h3 {
    font-size: clamp(1.55rem, 7vw, 1.85rem);
  }

  .faq summary {
    padding-right: 42px;
    font-size: 1.65rem;
  }

  .faq details p {
    padding-right: 0;
  }

  .final-cta .button {
    width: 100%;
  }

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

  .site-footer address,
  .site-footer small {
    grid-column: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }

  .js .margin-trace,
  .js.is-ready .margin-trace {
    opacity: 1;
    transform: none;
  }
}