:root {
  --ink: #11110f;
  --paper: #f1f0eb;
  --paper-bright: #faf9f5;
  --accent: #ff5a1f;
  --line: rgba(17, 17, 15, 0.18);
  --header-height: 78px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}
html[lang="zh-CN"] body { font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif; }
a { color: inherit; text-decoration: none; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }

.site-header {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: 50;
  height: var(--header-height);
  display: grid;
  grid-template-columns: minmax(190px, 1fr) auto auto;
  align-items: center;
  gap: clamp(18px, 2.6vw, 42px);
  padding: 0 3vw;
  color: var(--paper-bright);
  border-bottom: 1px solid rgba(255,255,255,.24);
  transition: background .25s ease, color .25s ease, border-color .25s ease;
}
.site-header.is-scrolled { background: rgba(241,240,235,.94); color: var(--ink); border-color: var(--line); backdrop-filter: blur(14px); }
.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 800; letter-spacing: -.04em; }
.brand-mark { width: 18px; height: 18px; background: var(--accent); clip-path: polygon(0 35%, 70% 35%, 100% 100%, 0 100%); }
.site-nav { display: flex; align-items: center; gap: clamp(20px, 2.8vw, 46px); font-size: .84rem; }
.site-nav a { position: relative; }
.site-nav a:not(.nav-cta)::after { content: ""; position: absolute; left: 0; right: 100%; bottom: -6px; height: 1px; background: currentColor; transition: right .2s ease; }
.site-nav a:not(.nav-cta):hover::after { right: 0; }
.nav-cta { padding: 13px 22px; border: 1px solid currentColor; border-radius: 100px; }
.header-tools { position: relative; z-index: 4; display: flex; align-items: center; gap: 8px; }
.language-switcher { position: relative; }
.language-switcher summary {
  min-width: 70px;
  min-height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 0 13px;
  border: 1px solid currentColor;
  border-radius: 100px;
  cursor: pointer;
  list-style: none;
  font-size: .74rem;
  letter-spacing: .08em;
  text-transform: uppercase;
}
.language-switcher summary::-webkit-details-marker { display: none; }
.language-switcher summary span:last-child { font-size: .9rem; transition: transform .2s ease; }
.language-switcher[open] summary span:last-child { transform: rotate(180deg); }
.language-menu {
  position: absolute;
  top: calc(100% + 11px);
  right: 0;
  min-width: 158px;
  display: grid;
  padding: 8px;
  background: var(--paper-bright);
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: 0 18px 50px rgba(0,0,0,.18);
}
.language-menu a { display: flex; align-items: center; min-height: 38px; padding: 0 11px; font-size: .82rem; }
.language-menu a:hover, .language-menu a[aria-current="page"] { background: var(--accent); color: #fff; }
.menu-toggle { display: none; background: transparent; border: 0; color: inherit; padding: 10px; }
.menu-toggle span:not(.sr-only) { display: block; width: 27px; height: 1px; background: currentColor; margin: 6px 0; }

.hero {
  position: relative;
  min-height: 100svh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  align-items: end;
  overflow: hidden;
  padding: calc(var(--header-height) + 6vh) 3vw 6vh;
  background: var(--ink);
  color: var(--paper-bright);
}
.hero-media { position: absolute; inset: 0; overflow: hidden; background: url("hero-concrete.jpg") center / cover no-repeat; }
.hero-media::after { content: ""; position: absolute; inset: 0; background: linear-gradient(90deg, rgba(13,13,11,.98) 0%, rgba(13,13,11,.72) 45%, rgba(13,13,11,.2) 100%); }
.hero-grid { position: absolute; inset: 0; opacity: .18; background-image: linear-gradient(rgba(255,255,255,.15) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,.15) 1px, transparent 1px); background-size: min(11vw, 160px) min(11vw, 160px); transform: perspective(700px) rotateX(58deg) scale(1.45) translateY(14%); transform-origin: center bottom; }
.hero-glow { position: absolute; width: 55vw; aspect-ratio: 1; right: -12vw; bottom: -32vw; border-radius: 50%; background: var(--accent); filter: blur(20px); opacity: .68; }
.hero-content, .hero-aside, .scroll-cue { position: relative; z-index: 2; }
.eyebrow, .section-kicker { margin: 0 0 4vh; font-size: .78rem; text-transform: uppercase; letter-spacing: .17em; }
.eyebrow::before, .section-kicker::before { content: ""; display: inline-block; width: 42px; height: 1px; margin: 0 12px 4px 0; background: currentColor; }
h1 { margin: 0; max-width: 990px; font-size: clamp(4rem, 8.6vw, 9rem); font-weight: 400; line-height: .82; letter-spacing: -.072em; }
h1 em { color: var(--accent); font-style: normal; }
html[lang="zh-CN"] h1,
html[lang="zh-CN"] .statement h2,
html[lang="zh-CN"] .process-content h2,
html[lang="zh-CN"] .projects-heading h2,
html[lang="zh-CN"] .scope > h2,
html[lang="zh-CN"] .calculator-preview h2,
html[lang="zh-CN"] .contact h2 { line-height: .96; letter-spacing: -.035em; }
.hero-copy { max-width: 520px; margin: 4vh 0 0; font-size: clamp(1rem, 1.45vw, 1.35rem); line-height: 1.45; color: rgba(255,255,255,.72); }
.hero-actions { display: flex; gap: 12px; margin-top: 4vh; }
.button { min-height: 52px; display: inline-flex; align-items: center; justify-content: center; gap: 40px; padding: 0 25px; border-radius: 100px; font-size: .88rem; transition: transform .2s ease, background .2s ease, color .2s ease; }
.button:hover { transform: translateY(-2px); }
.button-primary { background: var(--accent); color: #fff; }
.button-ghost { border: 1px solid rgba(255,255,255,.6); }
.hero-aside { align-self: center; justify-self: end; width: 190px; padding-top: 14px; border-top: 1px solid rgba(255,255,255,.55); }
.hero-aside span { display: block; color: var(--accent); font-size: .75rem; margin-bottom: 16px; }
.hero-aside p { margin: 0; line-height: 1.4; }
.scroll-cue { position: absolute; right: 3vw; bottom: 6vh; display: flex; gap: 30px; font-size: .75rem; text-transform: uppercase; letter-spacing: .13em; }

.statement { min-height: 90vh; display: grid; grid-template-columns: .6fr 2fr 1fr; gap: 5vw; align-items: start; padding: 13vh 3vw; background: var(--paper-bright); }
.section-kicker { font-size: .72rem; }
.statement h2 { margin: 0; font-size: clamp(3rem, 6.2vw, 7.4rem); line-height: .94; font-weight: 400; letter-spacing: -.06em; }
.statement h2 span { color: #77756e; }
.statement-copy { align-self: end; max-width: 390px; margin: 0; padding-top: 28px; border-top: 1px solid var(--line); font-size: 1.05rem; line-height: 1.6; }

.principles { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); background: var(--paper-bright); }
.principle { min-height: 420px; display: flex; flex-direction: column; justify-content: flex-end; padding: 42px 3vw; border-right: 1px solid var(--line); }
.principle:last-child { border-right: 0; }
.principle > span, .scope-card > span { margin-bottom: auto; color: #77756e; font: 12px/1.2 "Courier New", monospace; text-transform: uppercase; letter-spacing: .12em; }
.principle h3, .scope-card h3 { margin: 90px 0 18px; font-size: clamp(2rem, 3.4vw, 4rem); font-weight: 400; letter-spacing: -.05em; }
.principle p, .scope-card p { max-width: 370px; margin: 0; color: #5f5d57; line-height: 1.55; }

.process { display: grid; grid-template-columns: 1fr 1fr; min-height: 100vh; background: var(--ink); color: var(--paper-bright); }
.process-media { position: sticky; top: 0; align-self: start; height: 100vh; margin: 0; overflow: hidden; }
.process-media::after { content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, transparent 45%, rgba(0,0,0,.7)); }
.process-media img { width: 100%; height: 100%; object-fit: cover; filter: grayscale(55%) contrast(1.08); }
.process-media figcaption { position: absolute; z-index: 1; left: 4vw; bottom: 4vw; font-size: .78rem; text-transform: uppercase; letter-spacing: .16em; }
.process-content { padding: 12vh 5vw 8vh; }
.process-content h2, .scope > h2 { margin: 0 0 10vh; font-size: clamp(3.5rem, 6vw, 7.2rem); font-weight: 400; line-height: .92; letter-spacing: -.065em; }
.process-content h2 span { color: #6f6e69; }
.process-list { list-style: none; padding: 0; margin: 0; }
.process-list li { display: grid; grid-template-columns: 64px 1fr; gap: 2vw; padding: 30px 0; border-top: 1px solid rgba(255,255,255,.2); }
.process-list li > span { color: var(--accent); font: 12px/1 "Courier New", monospace; }
.process-list h3 { margin: 0 0 10px; font-size: 1.45rem; font-weight: 400; }
.process-list p { margin: 0; max-width: 430px; color: rgba(255,255,255,.55); line-height: 1.5; }

.projects { padding: 13vh 3vw; background: var(--paper); }
.projects-heading { display: grid; grid-template-columns: .55fr 1.45fr .7fr; gap: 5vw; align-items: end; margin-bottom: 9vh; }
.projects-heading .section-kicker { align-self: start; }
.projects-heading h2 { margin: 0; font-size: clamp(3.4rem, 6vw, 7rem); font-weight: 400; line-height: .92; letter-spacing: -.065em; }
.projects-heading > p:last-child { margin: 0; padding-top: 24px; border-top: 1px solid var(--line); color: #5f5d57; line-height: 1.55; }
.project-shot { margin: 0; }
.project-shot img { width: 100%; height: 100%; display: block; object-fit: cover; filter: saturate(.7); transition: filter .4s ease, transform .7s ease; }
.project-shot:hover img { filter: saturate(1); transform: scale(1.015); }
.project-shot-main { height: min(72vw, 900px); overflow: hidden; }
.project-shot-secondary { width: 58%; height: min(52vw, 680px); margin: 16vh 0 0 auto; overflow: hidden; }
.project-shot figcaption { display: flex; justify-content: space-between; padding: 15px 0 0; font: 12px/1.4 "Courier New", monospace; text-transform: uppercase; letter-spacing: .08em; }

.scope { padding: 13vh 3vw; background: var(--paper-bright); }
.scope .section-kicker { margin-bottom: 6vh; }
.scope > h2 { max-width: 950px; color: var(--ink); }
.scope-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--line); border: 1px solid var(--line); }
.scope-card { min-height: 430px; display: flex; flex-direction: column; padding: 35px; background: var(--paper-bright); transition: background .25s ease, color .25s ease; }
.scope-card:hover { background: var(--accent); color: #fff; }
.scope-card:hover p, .scope-card:hover > span { color: rgba(255,255,255,.75); }

.calculator-preview { padding: 13vh 3vw; background: var(--paper); overflow: hidden; }
.calculator-preview-heading { display: grid; grid-template-columns: .55fr 1.45fr .7fr; gap: 5vw; align-items: end; margin-bottom: 8vh; }
.calculator-preview-heading .section-kicker { align-self: start; }
.calculator-preview-heading h2 { margin: 0; font-size: clamp(3.4rem, 6vw, 7rem); font-weight: 400; line-height: .9; letter-spacing: -.065em; }
.calculator-preview-heading h2 em { color: var(--accent); font-style: normal; }
.calculator-preview-intro { padding-top: 24px; border-top: 1px solid var(--line); }
.calculator-preview-intro p { margin: 0 0 30px; color: #5f5d57; line-height: 1.55; }
.calculator-preview-frame { display: grid; grid-template-columns: minmax(0, 1.65fr) minmax(340px, .7fr); grid-template-rows: 52px auto; min-height: 650px; border: 1px solid var(--line); background: var(--paper-bright); box-shadow: 0 35px 90px rgba(17,17,15,.1); }
.preview-toolbar { grid-column: 1 / -1; display: flex; align-items: center; justify-content: space-between; padding: 0 22px; background: var(--ink); color: rgba(255,255,255,.62); font: 11px/1 "Courier New", monospace; letter-spacing: .12em; text-transform: uppercase; }
.preview-toolbar span:first-child { color: #fff; font-weight: 700; }
.preview-form { min-width: 0; padding: clamp(28px, 4vw, 60px); }
.preview-fields { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; padding-bottom: 54px; border-bottom: 1px solid var(--line); }
.preview-field { min-width: 0; }
.preview-field > span { display: block; margin-bottom: 12px; font-size: .82rem; }
.preview-field strong { min-height: 95px; display: flex; align-items: center; justify-content: space-between; padding: 0 22px; border: 1px solid var(--line); font-size: clamp(2.5rem, 4vw, 4.8rem); font-weight: 400; letter-spacing: -.05em; }
.preview-field strong small { color: #77756e; font: 11px/1 "Courier New", monospace; text-transform: uppercase; letter-spacing: .08em; }
.preview-field > i { --value: 18%; position: relative; display: block; height: 5px; margin-top: 17px; background: linear-gradient(90deg, var(--accent) var(--value), #3b3a36 var(--value)); border-radius: 9px; }
.preview-field > i::after { content: ""; position: absolute; left: var(--value); top: 50%; width: 14px; height: 14px; background: var(--accent); border-radius: 50%; transform: translate(-50%, -50%); }
.preview-types { padding-top: 42px; }
.preview-types > p { display: flex; gap: 14px; margin: 0 0 26px; font-size: 1.5rem; }
.preview-types > p b { color: var(--accent); font: 11px/1.8 "Courier New", monospace; }
.preview-types > div { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 10px; }
.preview-types > div > span { min-height: 176px; display: flex; flex-direction: column; padding: 20px; border: 1px solid var(--line); }
.preview-types > div > span.is-selected { border-color: var(--accent); background: rgba(255,90,31,.045); }
.preview-types span > i { width: 16px; height: 16px; margin-bottom: 36px; border: 1px solid #8c8a83; border-radius: 50%; }
.preview-types span.is-selected > i { border: 5px solid var(--accent); }
.preview-types span > b { font-size: .92rem; font-weight: 400; line-height: 1.3; }
.preview-types span > small { margin-top: auto; color: #77756e; font: 10px/1.3 "Courier New", monospace; }
.preview-result { position: relative; overflow: hidden; padding: clamp(32px, 4vw, 56px); background: var(--ink); color: #fff; }
.preview-result::after { content: ""; position: absolute; width: 360px; height: 360px; right: -190px; bottom: -185px; border: 46px solid rgba(255,90,31,.24); border-radius: 50%; }
.preview-result > * { position: relative; z-index: 1; }
.preview-result .section-kicker { margin-bottom: 45px; color: rgba(255,255,255,.62); }
.preview-result > span { display: block; color: rgba(255,255,255,.62); font-size: .82rem; }
.preview-result > strong { display: block; margin-top: 12px; color: var(--accent); font-size: clamp(2.2rem, 4vw, 4.6rem); font-weight: 400; line-height: .95; letter-spacing: -.055em; white-space: nowrap; }
.preview-result > small { display: block; margin-top: 14px; color: rgba(255,255,255,.68); }
.preview-breakdown { margin-top: 45px; padding-top: 30px; border-top: 1px solid rgba(255,255,255,.18); }
.preview-breakdown > p { margin: 0 0 18px; }
.preview-breakdown > span { display: flex; justify-content: space-between; gap: 18px; padding: 13px 0; border-bottom: 1px solid rgba(255,255,255,.12); font-size: .74rem; }
.preview-breakdown i { color: rgba(255,255,255,.62); font-style: normal; }
.preview-breakdown b { font-weight: 400; white-space: nowrap; }
.preview-result-button { display: flex; justify-content: space-between; align-items: center; min-height: 52px; margin-top: 42px; padding: 0 24px; background: var(--accent); border-radius: 100px; font-size: .82rem; }

.contact { position: relative; min-height: 92vh; display: grid; grid-template-columns: .5fr 1.7fr .7fr; gap: 4vw; align-items: start; padding: 11vh 3vw; background: var(--accent); color: #fff; overflow: hidden; }
.contact-index { position: absolute; right: -2vw; bottom: -12vw; font-size: 42vw; line-height: .8; letter-spacing: -.1em; color: rgba(0,0,0,.09); }
.contact h2 { position: relative; margin: 0; font-size: clamp(4rem, 8vw, 9.5rem); font-weight: 400; line-height: .84; letter-spacing: -.075em; }
.contact h2 em { color: var(--ink); font-style: normal; }
.contact-note { position: relative; align-self: end; }
.contact-note p { margin: 0 0 30px; padding-top: 25px; border-top: 1px solid rgba(255,255,255,.5); line-height: 1.55; }
.button-dark { background: var(--ink); color: #fff; }

.site-footer { display: grid; grid-template-columns: 1.25fr .85fr .4fr .55fr; gap: clamp(28px, 4vw, 76px); padding: 70px 3vw 35px; background: var(--ink); color: var(--paper-bright); }
.footer-brand { font-size: clamp(2.7rem, 5vw, 6rem); font-weight: 700; letter-spacing: -.065em; }
.site-footer p { margin: 8px 0 0; color: rgba(255,255,255,.58); line-height: 1.5; }
.site-footer nav { display: flex; flex-direction: column; gap: 12px; font-size: .85rem; }
.footer-company { display: flex; flex-direction: column; align-items: flex-start; gap: 12px; }
.footer-company > span { color: rgba(255,255,255,.48); font: 10px/1 "Courier New", monospace; text-transform: uppercase; letter-spacing: .13em; }
.footer-company-logo { width: 150px; height: 120px; overflow: hidden; background: #fff; }
.footer-company-logo img { width: 100%; height: auto; display: block; }
.footer-company strong { font-size: .8rem; font-weight: 400; letter-spacing: .02em; }
.site-footer .copyright { grid-column: 2 / -1; margin-top: 60px; padding-top: 20px; border-top: 1px solid rgba(255,255,255,.18); font: 11px/1.4 "Courier New", monospace; text-transform: uppercase; letter-spacing: .1em; }

.reveal { opacity: 0; transform: translateY(34px); transition: opacity .75s ease, transform .75s cubic-bezier(.22,1,.36,1); }
.reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (max-width: 800px) {
  :root { --header-height: 68px; }
  .site-header { grid-template-columns: 1fr auto; gap: 12px; padding: 0 14px 0 20px; }
  .menu-toggle { display: block; z-index: 3; }
  .site-nav { position: fixed; z-index: 2; inset: 0; display: flex; flex-direction: column; align-items: flex-start; justify-content: flex-end; gap: 25px; padding: 110px 24px 45px; background: var(--accent); color: #fff; font-size: 2rem; transform: translateY(-105%); transition: transform .35s cubic-bezier(.76,0,.24,1); }
  .site-nav.is-open { transform: translateY(0); }
  .language-switcher summary { min-width: 62px; min-height: 38px; padding: 0 10px; }
  .nav-cta { font-size: 1rem; margin-top: 20px; }
  .hero { min-height: 860px; grid-template-columns: 1fr; padding: 130px 20px 42px; align-items: start; }
  .hero-media::after { background: linear-gradient(180deg, rgba(13,13,11,.9), rgba(13,13,11,.62)); }
  .eyebrow { margin-bottom: 9vh; }
  h1 { font-size: clamp(4rem, 19vw, 6.2rem); line-height: .86; }
  .hero-copy { margin-top: 36px; max-width: 90%; }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .button { justify-content: space-between; }
  .hero-aside { display: none; }
  .scroll-cue { right: 20px; bottom: 20px; }
  .statement { min-height: auto; grid-template-columns: 1fr; gap: 48px; padding: 90px 20px; }
  .statement h2 { font-size: clamp(3.3rem, 15vw, 5rem); }
  .statement-copy { max-width: none; }
  .principles { grid-template-columns: 1fr; }
  .principle { min-height: 340px; padding: 32px 20px; border-right: 0; border-bottom: 1px solid var(--line); }
  .principle:last-child { border-bottom: 0; }
  .principle h3 { margin-top: 70px; }
  .process { grid-template-columns: 1fr; }
  .process-media { position: relative; height: 66vh; min-height: 480px; }
  .process-content { padding: 80px 20px; }
  .process-content h2 { margin-bottom: 70px; }
  .process-list li { grid-template-columns: 42px 1fr; gap: 12px; }
  .projects { padding: 90px 20px; }
  .projects-heading { grid-template-columns: 1fr; gap: 35px; }
  .projects-heading h2 { font-size: clamp(3.3rem, 14vw, 5rem); }
  .project-shot-main { height: 68vh; }
  .project-shot-secondary { width: 84%; height: 54vh; margin-top: 90px; }
  .project-shot figcaption { flex-direction: column; gap: 5px; }
  .scope { padding: 90px 20px; }
  .scope > h2 { font-size: clamp(3.3rem, 14vw, 5rem); }
  .scope-grid { grid-template-columns: 1fr; }
  .scope-card { min-height: 330px; }
  .calculator-preview { padding: 90px 20px; }
  .calculator-preview-heading { grid-template-columns: 1fr; gap: 35px; margin-bottom: 55px; }
  .calculator-preview-heading h2 { font-size: clamp(3.3rem, 14vw, 5rem); }
  .calculator-preview-frame { grid-template-columns: 1fr; grid-template-rows: 48px auto auto; }
  .preview-form { padding: 28px 20px 36px; }
  .preview-fields { grid-template-columns: 1fr; padding-bottom: 38px; }
  .preview-types > div { grid-template-columns: 1fr; }
  .preview-types > div > span { min-height: 118px; }
  .preview-types span > i { margin-bottom: 20px; }
  .preview-result { min-height: 510px; padding: 38px 24px; }
  .preview-result > strong { white-space: normal; }
  .contact { min-height: 840px; grid-template-columns: 1fr; gap: 30px; padding: 90px 20px 45px; }
  .contact h2 { font-size: clamp(4rem, 18vw, 6.5rem); }
  .contact-note { align-self: end; max-width: 470px; }
  .site-footer { grid-template-columns: 1fr; padding: 55px 20px 30px; }
  .site-footer nav { margin-top: 20px; }
  .site-footer .copyright { grid-column: auto; margin-top: 35px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation-duration: .01ms !important; transition-duration: .01ms !important; }
}