:root {
  --paper: #f5f7fa;
  --paper-strong: #ffffff;
  --ink: #12161d;
  --ink-soft: #5b6674;
  --line: #cfd6df;
  --line-soft: #e2e7ed;
  --brand-red: #e4492f;
  --brand-blue: #173f86;
  --travel: #2c6fa6;
  --travel-soft: #e4f0fb;
  --mail: #bd5e45;
  --mail-soft: #fcece5;
  --bird: #4b8556;
  --bird-soft: #e9f5e6;
  --content: 1180px;
  --header-height: 72px;
  --radius: 6px;
  --shadow: 0 24px 60px rgba(29, 43, 61, 0.13);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; background: var(--paper); }
body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, -apple-system, sans-serif;
  font-size: 16px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}
body.menu-open { overflow: hidden; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, input, textarea { font: inherit; }
button { color: inherit; }
ul, ol { margin: 0; padding: 0; list-style: none; }
h1, h2, h3, h4, p, figure { margin: 0; }

.skip-link {
  position: fixed;
  top: 10px;
  left: 10px;
  z-index: 1000;
  padding: 10px 14px;
  background: var(--ink);
  color: #fff;
  transform: translateY(-150%);
}
.skip-link:focus { transform: translateY(0); }
:focus-visible { outline: 3px solid var(--brand-red); outline-offset: 4px; }

.container { width: min(calc(100% - 48px), var(--content)); margin: 0 auto; }
.section { padding: 104px 0; border-top: 1px solid var(--line); }
.section--white { background: var(--paper-strong); }
.section-label {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  margin-bottom: 18px;
  color: var(--brand-red);
  font-size: 0.73rem;
  font-weight: 800;
  text-transform: uppercase;
}
.section-label::before { content: ""; width: 24px; height: 2px; background: currentColor; }
.section-heading { font-size: 2.65rem; line-height: 1.15; font-weight: 800; letter-spacing: 0; }
.section-intro { max-width: 680px; margin-top: 16px; color: var(--ink-soft); font-size: 1.03rem; }

.site-header {
  position: fixed;
  inset: 0 0 auto;
  z-index: 100;
  height: var(--header-height);
  border-bottom: 1px solid transparent;
  transition: background-color 180ms ease, border-color 180ms ease;
}
.site-header.is-scrolled {
  background: rgba(245, 247, 250, 0.94);
  border-color: var(--line);
  backdrop-filter: blur(14px);
}
.site-nav { height: 100%; display: flex; align-items: center; justify-content: space-between; }
.brand { display: inline-flex; align-items: center; gap: 10px; font-size: 1.08rem; font-weight: 900; }
.brand img { width: 34px; height: 34px; object-fit: contain; }
.nav-links { display: flex; align-items: center; gap: 30px; }
.nav-links a { color: var(--ink-soft); font-size: 0.84rem; font-weight: 650; }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--ink); }
.nav-contact { display: inline-flex; align-items: center; gap: 8px; padding: 9px 13px; background: var(--brand-blue); color: #fff !important; border-radius: 3px; }
.nav-contact svg, .button svg, .text-link svg { width: 15px; height: 15px; flex: 0 0 auto; }
.menu-button { display: none; width: 44px; height: 44px; padding: 0; border: 0; background: transparent; align-items: center; justify-content: center; cursor: pointer; }
.menu-icon, .menu-icon::before, .menu-icon::after { display: block; width: 22px; height: 2px; background: var(--ink); transition: 180ms ease; }
.menu-icon { position: relative; }
.menu-icon::before, .menu-icon::after { content: ""; position: absolute; left: 0; }
.menu-icon::before { top: -7px; }
.menu-icon::after { top: 7px; }
.menu-button[aria-expanded="true"] .menu-icon { background: transparent; }
.menu-button[aria-expanded="true"] .menu-icon::before { top: 0; transform: rotate(45deg); }
.menu-button[aria-expanded="true"] .menu-icon::after { top: 0; transform: rotate(-45deg); }
.mobile-menu { display: none; }

.studio-hero {
  min-height: calc(100svh - 36px);
  padding: 150px 0 92px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}
.studio-hero::before, .detail-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  background-image: linear-gradient(rgba(180, 190, 202, 0.28) 1px, transparent 1px), linear-gradient(90deg, rgba(180, 190, 202, 0.28) 1px, transparent 1px);
  background-size: 48px 48px;
}
.hero-grid { display: grid; grid-template-columns: 1.04fr 0.96fr; gap: 70px; align-items: center; position: relative; z-index: 1; }
.hero-overline { color: var(--brand-red); font-size: 0.75rem; font-weight: 850; margin-bottom: 22px; }
.hero-title { font-size: 4.65rem; line-height: 1.03; font-weight: 900; letter-spacing: 0; }
.hero-title em { color: var(--brand-red); font-style: normal; }
.hero-lead { max-width: 620px; margin-top: 24px; color: var(--ink-soft); font-size: 1.09rem; line-height: 1.9; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.button { min-height: 46px; display: inline-flex; align-items: center; justify-content: center; gap: 9px; padding: 0 18px; border: 1px solid var(--line); border-radius: 3px; font-size: 0.86rem; font-weight: 750; transition: transform 160ms ease, background-color 160ms ease; }
.button:hover { transform: translateY(-2px); }
.button--primary { background: var(--brand-blue); border-color: var(--brand-blue); color: #fff; }
.button--quiet { background: rgba(255, 255, 255, 0.54); }
.hero-visual { min-height: 430px; position: relative; }
.coordinate-mark { position: absolute; width: 190px; height: 190px; right: 4%; top: 8%; border: 1px solid var(--brand-red); border-radius: 50%; color: var(--brand-red); }
.coordinate-mark::before, .coordinate-mark::after { content: ""; position: absolute; background: currentColor; }
.coordinate-mark::before { width: 246px; height: 1px; left: -28px; top: 94px; }
.coordinate-mark::after { width: 1px; height: 246px; left: 94px; top: -28px; }
.coordinate-mark span { position: absolute; top: 80px; left: 46px; font-size: 0.66rem; font-weight: 800; }
.project-sheet { position: absolute; width: 230px; aspect-ratio: 4 / 5; padding: 22px; border: 1px solid rgba(24, 31, 41, 0.14); border-radius: 4px; box-shadow: var(--shadow); display: flex; flex-direction: column; justify-content: flex-end; }
.project-sheet small { font-size: 0.65rem; color: var(--ink-soft); }
.project-sheet strong { margin-top: 6px; font-size: 1.26rem; }
.project-sheet--travel { top: 26px; left: 4%; background: var(--travel-soft); transform: rotate(-7deg); }
.project-sheet--mail { top: 3px; left: 34%; background: var(--mail-soft); transform: rotate(4deg); }
.project-sheet--bird { top: 76px; left: 60%; background: var(--bird-soft); transform: rotate(10deg); }

.section-head { display: flex; justify-content: space-between; align-items: flex-end; gap: 30px; margin-bottom: 42px; }
.section-meta { color: var(--ink-soft); font-size: 0.78rem; white-space: nowrap; }
.project-grid { display: grid; grid-template-columns: 1.35fr 1fr 1fr; gap: 14px; }
.project-card { min-height: 460px; display: flex; flex-direction: column; border: 1px solid var(--line); background: #fff; border-radius: var(--radius); overflow: hidden; transition: transform 180ms ease, box-shadow 180ms ease; }
.project-card:hover { transform: translateY(-4px); box-shadow: 0 18px 42px rgba(29, 43, 61, 0.12); }
.project-media { min-height: 260px; flex: 1 1 auto; display: flex; align-items: center; justify-content: center; overflow: hidden; position: relative; }
.project-card--travel .project-media { background: var(--travel-soft); }
.project-card--mail .project-media { background: var(--mail-soft); }
.project-card--bird .project-media { background: var(--bird-soft); }
.project-media img { width: 100%; height: 100%; object-fit: cover; }
.project-card--mail .project-media img { width: auto; height: 91%; border: 5px solid #26333f; border-radius: 22px; box-shadow: 16px 16px 0 rgba(255,255,255,.64); }
.project-card--bird .project-media img { object-fit: cover; }
.project-body { padding: 24px; border-top: 1px solid var(--line); }
.project-type { color: var(--ink-soft); font-size: 0.66rem; font-weight: 750; }
.project-body h3 { margin-top: 9px; font-size: 1.52rem; }
.project-body p { margin-top: 10px; color: var(--ink-soft); font-size: 0.88rem; }
.project-footer { display: flex; justify-content: space-between; align-items: center; margin-top: 22px; gap: 16px; }
.status { display: inline-flex; align-items: center; gap: 8px; font-size: 0.73rem; font-weight: 750; }
.status::before { content: ""; width: 7px; height: 7px; border-radius: 50%; background: #21a36d; }
.status--prototype::before { background: #dba51d; }
.text-link { display: inline-flex; align-items: center; gap: 8px; color: var(--brand-blue); font-size: 0.78rem; font-weight: 800; }

.practice-list { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid var(--line); background: var(--line); gap: 1px; }
.practice-item { min-height: 190px; padding: 24px; background: #fff; display: flex; flex-direction: column; justify-content: space-between; }
.practice-index { color: var(--brand-red); font-size: 0.68rem; font-weight: 800; }
.practice-item h3 { font-size: 1.15rem; }
.practice-item p { margin-top: 8px; color: var(--ink-soft); font-size: 0.83rem; }

.method-layout { display: grid; grid-template-columns: 0.8fr 1.2fr; gap: 80px; }
.method-intro { max-width: 460px; }
.method-list { border-top: 1px solid #3a4049; }
.method-item { display: grid; grid-template-columns: 62px 1fr; gap: 20px; padding: 24px 0; border-bottom: 1px solid #3a4049; }
.method-item span { color: #ff7057; font-size: 0.75rem; font-weight: 800; }
.method-item h3 { color: #fff; font-size: 1.18rem; }
.method-item p { margin-top: 6px; color: #aeb6c1; font-size: 0.86rem; }
.section--dark { background: #11151b; color: #fff; }
.section--dark .section-intro { color: #aeb6c1; }

.about-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 80px; align-items: start; }
.about-copy { color: var(--ink-soft); font-size: 1rem; }
.about-copy p + p { margin-top: 18px; }
.about-ledger { border-top: 1px solid var(--line); }
.ledger-row { display: grid; grid-template-columns: 145px 1fr; gap: 24px; padding: 18px 0; border-bottom: 1px solid var(--line); }
.ledger-row b { font-size: 0.76rem; color: var(--brand-red); }
.ledger-row span { font-size: 0.88rem; }

.contact-band { background: var(--brand-blue); color: #fff; }
.contact-layout { display: flex; justify-content: space-between; gap: 50px; align-items: center; }
.contact-layout h2 { font-size: 2.7rem; line-height: 1.15; }
.contact-layout p { margin-top: 12px; color: #cbd8ef; }
.contact-action { flex: 0 0 auto; min-width: 220px; background: #fff; color: var(--brand-blue); border-color: #fff; }

.site-footer { padding: 54px 0 28px; border-top: 1px solid var(--line); background: #fff; }
.footer-top { display: grid; grid-template-columns: 1.3fr 1fr 1fr; gap: 50px; }
.footer-brand p { margin-top: 14px; max-width: 360px; color: var(--ink-soft); font-size: 0.86rem; }
.footer-col h3 { font-size: 0.76rem; margin-bottom: 14px; }
.footer-col li + li { margin-top: 8px; }
.footer-col a, .footer-col span { color: var(--ink-soft); font-size: 0.82rem; }
.footer-bottom { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 14px; margin-top: 42px; padding-top: 20px; border-top: 1px solid var(--line); color: var(--ink-soft); font-size: 0.75rem; }
.footer-legal { display: flex; flex-wrap: wrap; gap: 14px; }

.detail-main { padding-top: var(--header-height); }
.detail-hero { min-height: 640px; position: relative; border-bottom: 1px solid var(--line); overflow: hidden; }
.detail-hero-grid { min-height: 640px; display: grid; grid-template-columns: 1fr 1fr; position: relative; z-index: 1; }
.detail-hero-copy { padding: 92px 58px 58px 0; display: flex; flex-direction: column; justify-content: space-between; }
.breadcrumb { display: inline-flex; align-items: center; gap: 7px; color: var(--ink-soft); font-size: 0.77rem; font-weight: 700; }
.breadcrumb svg { width: 16px; height: 16px; flex: 0 0 auto; }
.breadcrumb:hover { color: var(--project-accent, var(--brand-blue)); }
.detail-code { margin-top: 42px; color: var(--project-accent, var(--brand-red)); font-size: 0.73rem; font-weight: 800; }
.detail-title { margin-top: 14px; font-size: 4.35rem; line-height: 1; font-weight: 900; }
.detail-lead { max-width: 580px; margin-top: 22px; color: var(--ink-soft); font-size: 1.05rem; line-height: 1.85; }
.detail-meta { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-top: 42px; padding-top: 18px; border-top: 1px solid var(--line); }
.detail-meta dt { color: var(--ink-soft); font-size: 0.7rem; }
.detail-meta dd { margin: 4px 0 0; font-size: 0.86rem; font-weight: 800; }
.detail-visual { border-left: 1px solid var(--line); background: var(--project-soft, #edf2f7); min-height: 640px; display: flex; align-items: center; justify-content: center; padding: 50px; position: relative; overflow: hidden; }
.detail-visual::before { content: attr(data-label); position: absolute; top: 22px; left: 24px; color: var(--ink-soft); font-size: 0.66rem; font-weight: 800; }
.detail-visual img { max-height: 510px; width: auto; border: 6px solid #1e2a35; border-radius: 24px; box-shadow: 24px 24px 0 rgba(255, 255, 255, 0.62), var(--shadow); }
.detail-visual--wide img { width: 100%; max-height: none; border-width: 1px; border-radius: 4px; object-fit: cover; }
.detail-visual--concept img { width: 100%; max-height: none; border-width: 1px; border-radius: 4px; }
.detail-caption { position: absolute; right: 22px; bottom: 20px; padding: 7px 10px; border: 1px solid rgba(18, 22, 29, 0.18); background: rgba(255, 255, 255, 0.92); color: var(--ink-soft); font-size: 0.68rem; font-weight: 750; }
.detail-caption--concept { display: flex; align-items: center; gap: 9px; color: var(--ink); }
.detail-caption--concept strong { color: var(--project-accent, var(--bird)); }
.detail-caption--concept span { color: var(--ink-soft); font-weight: 650; }
.detail-section { padding: 90px 0; border-bottom: 1px solid var(--line); }
.detail-section-grid { display: grid; grid-template-columns: 0.6fr 1.4fr; gap: 70px; }
.detail-section-index { color: var(--project-accent, var(--brand-red)); font-size: 0.72rem; font-weight: 800; }
.detail-section h2 { margin-top: 9px; font-size: 2.2rem; line-height: 1.2; }
.detail-section-copy { color: var(--ink-soft); font-size: 1rem; }
.experience-flow { display: grid; grid-template-columns: repeat(4, 1fr); margin-top: 34px; border: 1px solid var(--line); }
.flow-step { min-height: 145px; padding: 22px; background: #fff; border-right: 1px solid var(--line); }
.flow-step:last-child { border-right: 0; }
.flow-step span { color: var(--project-accent, var(--brand-blue)); font-size: 0.68rem; font-weight: 800; }
.flow-step strong { display: block; margin-top: 34px; font-size: 0.94rem; }
.progress-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 30px; margin-top: 36px; }
.progress-panel { padding-top: 17px; border-top: 4px solid var(--brand-blue); }
.progress-panel--next { border-color: var(--brand-red); }
.progress-panel h3 { font-size: 1rem; }
.progress-panel li { position: relative; margin-top: 10px; padding-left: 18px; color: var(--ink-soft); font-size: 0.88rem; }
.progress-panel li::before { content: ""; width: 6px; height: 6px; border: 1px solid currentColor; position: absolute; left: 0; top: 0.65em; }
.tech-list { display: flex; flex-wrap: wrap; gap: 0; margin-top: 30px; border-top: 1px solid var(--line); border-left: 1px solid var(--line); }
.tech-list li { padding: 10px 14px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); background: #fff; font-size: 0.78rem; font-weight: 750; }
.related-projects { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; margin-top: 34px; }
.related-projects--two { grid-template-columns: repeat(2, 1fr); }
.related-card { min-height: 150px; padding: 22px; border: 1px solid var(--line); background: #fff; display: flex; flex-direction: column; justify-content: space-between; }
.related-card:hover { border-color: var(--project-accent, var(--brand-blue)); }
.related-card strong { font-size: 1.08rem; }
.related-card span { color: var(--ink-soft); font-size: 0.76rem; }
.detail-related { background: var(--project-soft, var(--paper)); }

.legacy-hero { padding: 150px 0 76px; border-bottom: 1px solid var(--line); position: relative; overflow: hidden; }
.legacy-hero::before { content: ""; position: absolute; inset: 0; background-image: linear-gradient(rgba(180,190,202,.24) 1px, transparent 1px), linear-gradient(90deg, rgba(180,190,202,.24) 1px, transparent 1px); background-size: 48px 48px; }
.legacy-hero .container { position: relative; z-index: 1; }
.legacy-hero .section-label { display: flex; width: max-content; margin-top: 42px; margin-bottom: 0; color: var(--brand-red); font-size: 0.73rem; }
.legacy-hero h1 { margin-top: 18px; font-size: 4rem; line-height: 1; }
.legacy-hero p { max-width: 700px; margin-top: 22px; color: var(--ink-soft); font-size: 1.05rem; }
.legacy-hero .detail-meta { max-width: 760px; }
.feature-list { display: grid; grid-template-columns: repeat(3, 1fr); border: 1px solid var(--line); background: var(--line); gap: 1px; margin-top: 40px; }
.feature-item { min-height: 210px; padding: 25px; background: #fff; }
.feature-number { color: var(--brand-red); font-size: 0.7rem; font-weight: 800; }
.feature-item h3 { margin-top: 30px; font-size: 1.04rem; }
.feature-item p { margin-top: 9px; color: var(--ink-soft); font-size: 0.84rem; }

[data-reveal] { opacity: 0; transform: translateY(20px); transition: opacity 520ms ease, transform 520ms ease; }
[data-reveal].is-visible { opacity: 1; transform: none; }

@media (max-width: 1040px) {
  .hero-title { font-size: 3.8rem; }
  .project-sheet { width: 190px; }
  .project-grid { grid-template-columns: 1fr 1fr; }
  .project-card:first-child { grid-column: 1 / -1; min-height: 400px; }
  .project-card:first-child .project-media { min-height: 340px; }
  .practice-list { grid-template-columns: 1fr 1fr; }
  .detail-title { font-size: 3.5rem; }
}

@media (max-width: 820px) {
  :root { --header-height: 64px; }
  .container { width: min(calc(100% - 32px), var(--content)); }
  .nav-links { display: none; }
  .menu-button { display: inline-flex; }
  .mobile-menu { position: fixed; inset: var(--header-height) 0 0; z-index: 90; display: flex; flex-direction: column; justify-content: center; padding: 32px; background: rgba(245,247,250,.98); opacity: 0; pointer-events: none; transition: opacity 180ms ease; }
  .mobile-menu.is-open { opacity: 1; pointer-events: auto; }
  .mobile-menu a { display: block; padding: 16px 0; border-bottom: 1px solid var(--line); font-size: 1.35rem; font-weight: 750; }
  .studio-hero { min-height: auto; padding: 122px 0 72px; }
  .hero-grid, .method-layout, .about-layout, .detail-section-grid { grid-template-columns: 1fr; gap: 50px; }
  .hero-title { font-size: 3.2rem; }
  .hero-visual { min-height: 360px; }
  .coordinate-mark { opacity: .42; }
  .project-sheet { width: 180px; }
  .project-sheet--travel { left: 0; }
  .project-sheet--mail { left: 29%; }
  .project-sheet--bird { left: 55%; }
  .section { padding: 78px 0; }
  .section-heading { font-size: 2.25rem; }
  .section-head { align-items: flex-start; flex-direction: column; }
  .project-grid { grid-template-columns: 1fr; }
  .project-card:first-child { grid-column: auto; }
  .method-layout { gap: 42px; }
  .contact-layout { align-items: flex-start; flex-direction: column; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
  .detail-hero-grid { grid-template-columns: 1fr; }
  .detail-hero-copy { padding: 70px 0 48px; min-height: 540px; }
  .detail-visual { min-height: 520px; border-left: 0; border-top: 1px solid var(--line); }
  .experience-flow { grid-template-columns: 1fr 1fr; }
  .flow-step:nth-child(2) { border-right: 0; }
  .flow-step:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .related-projects, .related-projects--two { grid-template-columns: 1fr; }
  .legacy-hero h1 { font-size: 3.2rem; }
  .feature-list { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 560px) {
  #projects { padding-top: 44px; }
  .studio-hero { padding-bottom: 22px; }
  .hero-grid { gap: 22px; }
  .hero-title { font-size: 2.55rem; }
  .hero-lead { font-size: 1rem; }
  .hero-visual { min-height: 220px; }
  .coordinate-mark { width: 138px; height: 138px; right: 4%; }
  .coordinate-mark::before { width: 176px; left: -19px; top: 68px; }
  .coordinate-mark::after { height: 176px; left: 68px; top: -19px; }
  .coordinate-mark span { top: 58px; left: 25px; }
  .project-sheet { width: 132px; padding: 15px; }
  .project-sheet--travel { top: 24px; left: 1%; }
  .project-sheet--mail { top: 2px; left: 30%; }
  .project-sheet--bird { top: 36px; left: 57%; }
  .project-card { min-height: 410px; }
  .project-card:first-child .project-media { min-height: 250px; }
  .practice-list { grid-template-columns: 1fr; }
  .practice-item { min-height: 155px; }
  .contact-layout h2 { font-size: 2.15rem; }
  .footer-top { grid-template-columns: 1fr; }
  .footer-brand { grid-column: auto; }
  .footer-bottom { flex-direction: column; }
  .detail-title { font-size: 2.75rem; }
  .detail-meta { grid-template-columns: 1fr; gap: 12px; }
  .detail-hero-copy { min-height: auto; }
  .detail-visual { min-height: 430px; padding: 48px 28px 34px; }
  .detail-visual img { max-height: 350px; box-shadow: 14px 14px 0 rgba(255,255,255,.62), var(--shadow); }
  .detail-caption { right: 14px; bottom: 12px; }
  .detail-caption--concept { align-items: flex-start; flex-direction: column; gap: 1px; }
  .detail-section { padding: 68px 0; }
  .detail-section h2 { font-size: 1.85rem; }
  .experience-flow, .progress-grid { grid-template-columns: 1fr; }
  .flow-step { border-right: 0; border-bottom: 1px solid var(--line); }
  .flow-step:last-child { border-bottom: 0; }
  .legacy-hero { padding: 120px 0 62px; }
  .legacy-hero h1 { font-size: 2.65rem; }
  .feature-list { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; animation-iteration-count: 1 !important; }
  [data-reveal] { opacity: 1; transform: none; }
}