:root {
  --paper: #fff;
  --ink: #000;
  --line: #dedede;
  --gutter: clamp(24px, 5vw, 88px);
  --sans: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 28px; }
body { margin: 0; background: #fff; color: #000; font: 16px/1.85 var(--sans); -webkit-font-smoothing: antialiased; }
body.menu-open { overflow: hidden; }
a { color: #000; text-decoration: none; }
button { color: #000; font: inherit; cursor: pointer; }
button, a { -webkit-tap-highlight-color: transparent; }
img { display: block; width: 100%; object-fit: contain; }
h1, h2, h3, p, figure { margin: 0; }
h2 { font-size: clamp(30px, 3vw, 46px); font-weight: 400; line-height: 1.5; letter-spacing: -.015em; }
h3 { font-size: 20px; font-weight: 500; line-height: 1.6; }
p { overflow-wrap: break-word; }
[hidden] { display: none !important; }
a:focus-visible, button:focus-visible, summary:focus-visible, [role="tabpanel"]:focus-visible { outline: 2px solid #000; outline-offset: 6px; }
::selection { background: #e1e1e1; color: #000; }
.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; }
.skip-link { position: fixed; left: 20px; top: 10px; z-index: 100; background: #fff; width: 1px; height: 1px; padding: 0; border: 0; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }
.skip-link:focus { width: auto; height: auto; padding: 10px 20px; border: 1px solid #000; clip-path: none; }
.header { height: 100px; margin: 0 var(--gutter); display: flex; align-items: center; justify-content: space-between; gap: 30px; position: relative; z-index: 30; }
.brand { display: flex; flex-direction: column; line-height: 1.4; flex-shrink: 0; }
.brand-zh { font-size: 18px; letter-spacing: .08em; font-weight: 500; }
.brand-en { font-size: 10px; letter-spacing: .14em; margin-top: 4px; }
html[lang="en"] .brand-zh { font-size: 18px; letter-spacing: -.02em; }
.studio-logo { width: 180px; height: 64px; object-fit: contain; }
.desktop-nav { display: flex; gap: clamp(24px, 3vw, 44px); font-size: 14px; }
.desktop-nav a { position: relative; padding: 12px 0; white-space: nowrap; }
.desktop-nav a::after { content: ''; position: absolute; bottom: 3px; left: 0; width: 100%; height: 1px; background: #000; transform: scaleX(0); transform-origin: left; transition: transform .35s; }
.desktop-nav a:hover::after, .desktop-nav a[aria-current]::after { transform: scaleX(1); }
.header-tools { display: flex; align-items: center; gap: 26px; }
.language-switch { display: flex; align-items: center; gap: 10px; font-size: 13px; white-space: nowrap; }
.language-switch a { padding: 5px 0; position: relative; }
.language-switch a[aria-current]::after { content: ''; position: absolute; bottom: 2px; left: 0; right: 0; height: 1px; background: #000; }
.language-switch a:hover { text-decoration: underline; text-underline-offset: 6px; }
.menu-toggle { display: none; background: #fff; border: 0; padding: 12px 0 12px 8px; align-items: center; gap: 12px; font-size: 14px; }
.menu-glyph { width: 22px; height: 13px; display: flex; flex-direction: column; justify-content: space-between; }
.menu-glyph i { display: block; height: 1px; background: #000; transition: transform .3s; }
.menu-toggle[aria-expanded="true"] .menu-glyph i:first-child { transform: translateY(6px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] .menu-glyph i:last-child { transform: translateY(-6px) rotate(-45deg); }
.mobile-menu { position: fixed; inset: 0; padding: 125px var(--gutter) 40px; background: #fff; z-index: 20; overflow-y: auto; }
.mobile-menu a { display: flex; gap: 28px; padding: 15px 0; border-bottom: 1px solid var(--line); font-size: 26px; }
.menu-number { font-size: 12px; line-height: 4; }
.mobile-menu p { margin-top: 45px; font-size: 12px; letter-spacing: .12em; }
.hero { min-height: calc(100svh - 100px); position: relative; padding: 45px var(--gutter) 30px; display: flex; flex-direction: column; justify-content: space-between; }
.hero-center { text-align: center; margin: auto 0; padding: 10px 0 65px; }
.hero-center h1 { display: flex; justify-content: center; }
.hero-logo { width: clamp(310px, 42vw, 590px); height: auto; max-height: 54svh; }
.hero-product { margin-top: 32px; font-size: 19px; font-weight: 500; letter-spacing: .3em; padding-left: .3em; }
.hero-type { font-size: 12px; margin-top: 12px; letter-spacing: .05em; }
.hero-separator { padding: 0 14px; }
.hero-thesis { margin-top: 26px; font-size: 17px; letter-spacing: .12em; }
html[lang="en"] .hero-thesis { letter-spacing: .015em; }
.hero-bottom { display: flex; justify-content: space-between; align-items: end; gap: 20px; font-size: 10px; letter-spacing: .12em; }
.text-link { display: inline-block; font-size: 14px; position: relative; letter-spacing: 0; }
.link-line { display: block; height: 1px; background: #000; margin-top: 5px; transition: transform .4s; transform-origin: left; }
.text-link:hover .link-line, .back-top:hover .link-line { transform: scaleX(.55); }
.section-shell { padding: 110px var(--gutter); border-top: 1px solid var(--line); }
.section-label { font-size: 12px; letter-spacing: .1em; margin-bottom: 40px; }
.intro-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 9vw; align-items: end; }
.lead { max-width: 580px; line-height: 2; }
.principles { display: grid; grid-template-columns: repeat(3, 1fr); gap: 5vw; margin-top: 80px; }
.principle { border-top: 1px solid var(--line); padding-top: 20px; }
.principle-top { display: flex; justify-content: space-between; font-size: 12px; letter-spacing: .08em; }
.principle h3 { margin-top: 32px; margin-bottom: 18px; font-size: 19px; }
.principle p { font-size: 15px; line-height: 1.95; }
.game-heading { display: grid; grid-template-columns: 1fr 1.2fr; gap: 7vw; align-items: center; }
.game-lockup { padding: 0 30px; }
.section-logo { width: 220px; height: 208px; }
.game-type { display: block; font-size: 11px; letter-spacing: .08em; margin-top: 30px; }
.game-intro-copy h2 { font-size: clamp(30px, 3.2vw, 46px); }
.game-intro-copy .lead { margin-top: 25px; }
.game-explorer { margin-top: 75px; }
.chapter-tabs { display: flex; width: 100%; border-bottom: 1px solid var(--line); gap: 55px; }
.chapter-tabs button { background: #fff; border: 0; position: relative; padding: 18px 0; min-height: 56px; font-size: 16px; display: flex; align-items: center; gap: 14px; }
.chapter-tabs button span { font-size: 12px; letter-spacing: .06em; }
.chapter-tabs button::after { content: ''; position: absolute; bottom: -1px; left: 0; right: 0; height: 2px; background: #000; transform: scaleX(0); transform-origin: left; transition: transform .3s; }
.chapter-tabs button[aria-selected="true"]::after { transform: scaleX(1); }
.chapter-tabs button:hover::after { transform: scaleX(1); }
.chapter-panel { display: grid; grid-template-columns: 1fr 1.2fr; gap: 7vw; padding: 60px 0 10px; align-items: start; min-height: 320px; }
.chapter-index { padding-left: 30px; }
.chapter-number { display: block; font-size: clamp(80px, 8vw, 115px); line-height: 1.1; font-weight: 300; letter-spacing: -.07em; }
.chapter-english { display: block; font-size: 11px; letter-spacing: .08em; margin-top: 24px; }
.chapter-copy h3 { font-size: 26px; font-weight: 400; line-height: 1.65; margin-bottom: 22px; max-width: 430px; }
.chapter-copy > p { font-size: 15px; line-height: 1.95; }
.chapter-detail { padding-top: 22px; margin-top: 28px; border-top: 1px solid var(--line); font-size: 14px; }
.game-note { font-size: 12px; margin-top: 40px; max-width: 800px; }
.tech-sequence { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 75px; border-top: 1px solid var(--line); }
.tech-item { display: flex; align-items: start; gap: 28px; padding: 30px 35px 15px 0; }
.tech-item + .tech-item { padding-left: 30px; border-left: 1px solid var(--line); }
.roman { font-size: 37px; font-weight: 300; line-height: 1.3; min-width: 38px; }
.tech-item h3 { font-size: 20px; }
.tech-item p { font-size: 14px; margin-top: 12px; max-width: 250px; }
.development h2 { max-width: 650px; }
.stages { padding: 0; margin: 70px 0 80px; display: grid; grid-template-columns: repeat(3, 1fr); gap: 4vw; list-style: none; }
.stage { border-top: 1px solid var(--line); padding-top: 18px; }
.stage.current { border-top: 2px solid #000; padding-top: 17px; }
.stage-top { display: flex; justify-content: space-between; font-size: 12px; gap: 12px; }
.stage h3 { margin-top: 28px; }
.stage > p { font-size: 14px; margin-top: 12px; max-width: 330px; }
.records-heading { display: flex; justify-content: space-between; align-items: center; margin-bottom: 25px; gap: 20px; }
.records-heading h3 { font-size: 18px; }
.records-heading > span { font-size: 11px; letter-spacing: .1em; }
.record { border-top: 1px solid var(--line); }
.record:last-child { border-bottom: 1px solid var(--line); }
.record summary { list-style: none; display: grid; grid-template-columns: 40px 1fr auto 30px; gap: 30px; align-items: center; padding: 30px 0; cursor: pointer; }
.record summary::-webkit-details-marker { display: none; }
.record-number { font-size: 12px; }
.record-title { font-size: 20px; line-height: 1.7; }
.record-category { display: block; font-size: 11px; letter-spacing: .1em; margin-top: 6px; }
.record-status { font-size: 13px; }
.record-plus { width: 22px; height: 22px; position: relative; }
.record-plus::before, .record-plus::after { content: ''; position: absolute; left: 0; top: 50%; width: 20px; height: 1px; background: #000; transition: transform .3s; }
.record-plus::after { transform: rotate(90deg); }
.record[open] .record-plus::after { transform: rotate(0); }
.record summary:hover .record-title { text-decoration: underline; text-underline-offset: 5px; }
.record-body { padding: 0 60px 35px 70px; max-width: 850px; font-size: 15px; line-height: 2; }
.development-gallery { display: grid; grid-template-columns: repeat(2, 1fr); gap: 30px; margin-bottom: 60px; }
.development-gallery img { aspect-ratio: 16 / 10; object-fit: cover; }
.development-gallery figcaption, .studio-photo figcaption { margin-top: 12px; font-size: 12px; }
.studio { padding-top: 130px; padding-bottom: 130px; }
.studio-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 9vw; align-items: start; }
.studio-body { padding-top: 66px; max-width: 550px; }
.studio-body > p + p { margin-top: 22px; }
.studio-signature { margin-top: 44px; display: flex; flex-direction: column; }
.studio-signature > span { font-size: 21px; letter-spacing: .05em; }
.studio-signature small { font-size: 11px; letter-spacing: .13em; margin-top: 9px; }
.studio-photo { margin-top: 70px; }
.studio-photo img { aspect-ratio: 16 / 8; object-fit: cover; }
.team { display: grid; grid-template-columns: repeat(3, 1fr); gap: 45px; margin-top: 70px; }
.team-member img { aspect-ratio: 4 / 5; object-fit: cover; }
.team-member figcaption { margin-top: 20px; }
.team-member figcaption p { font-size: 14px; }
.team-member > p { font-size: 14px; margin-top: 10px; }
.contact { padding-bottom: 35px; }
.contact-grid { display: grid; grid-template-columns: 1.15fr 1fr; gap: 9vw; align-items: end; }
.contact-info { padding-bottom: 15px; }
.contact-pending { font-size: 14px; margin-top: 20px; }
.contact-email { display: inline-block; border-bottom: 1px solid #000; padding: 12px 0; font-size: clamp(16px, 1.8vw, 24px); overflow-wrap: anywhere; }
.social-links { display: flex; gap: 28px; font-size: 14px; margin-top: 25px; flex-wrap: wrap; }
.footer-bottom { display: flex; justify-content: space-between; align-items: end; border-top: 1px solid var(--line); margin-top: 90px; padding-top: 28px; gap: 30px; font-size: 12px; }
.footer-brand .brand-zh { font-size: 17px; }
.footer-development { font-size: 11px; letter-spacing: .1em; }
.back-top { font-size: 14px; }
.reveal-ready { transform: translateY(10px); }
.reveal { transition: transform .6s cubic-bezier(.2,.65,.3,1); }
@media (min-width: 1500px) {
  .section-shell { padding-top: 130px; padding-bottom: 130px; }
  .contact { padding-bottom: 35px; }
}
@media (max-width: 1100px) {
  .desktop-nav { gap: 22px; }
  html[lang="en"] .brand-zh { font-size: 16px; }
  html[lang="en"] .desktop-nav { gap: 18px; font-size: 13px; }
  .intro-grid, .studio-grid, .contact-grid { gap: 5vw; }
  .principles { gap: 30px; }
  .principle h3 { font-size: 17px; }
  .chapter-copy h3 { font-size: 23px; }
  .tech-item { gap: 15px; padding-right: 20px; }
  .tech-item + .tech-item { padding-left: 20px; }
}
@media (max-width: 850px) {
  .header { height: 88px; gap: 20px; }
  .desktop-nav { display: none; }
  .menu-toggle { display: flex; }
  .header-tools { gap: 24px; }
  .hero { min-height: calc(100svh - 88px); padding-top: 40px; }
  .hero-logo { width: min(62vw, 510px); max-height: 48svh; }
  .hero-center { padding-bottom: 70px; }
}
@media (max-width: 760px) {
  .hero-logo { width: min(76vw, 440px); max-height: 46svh; }
  .hero-center { padding-bottom: 65px; }
  .hero-product { margin-top: 24px; font-size: 18px; }
  .hero-type { font-size: 11px; }
  .hero-thesis { font-size: 15px; margin-top: 23px; letter-spacing: .08em; }
  .hero-bottom { font-size: 9px; }
  .hero-bottom .text-link { font-size: 12px; }
  .section-shell { padding-top: 75px; padding-bottom: 75px; }
  .section-label { font-size: 11px; margin-bottom: 28px; }
  h2 { font-size: clamp(28px, 5vw, 37px); line-height: 1.5; }
  .intro-grid, .studio-grid, .contact-grid { grid-template-columns: 1fr; gap: 30px; }
  .lead { font-size: 15px; }
  .principles { grid-template-columns: 1fr; margin-top: 48px; gap: 32px; }
  .principle { display: grid; grid-template-columns: 64px 1fr; column-gap: 20px; padding-top: 20px; }
  .principle-top { flex-direction: column; justify-content: start; align-items: start; gap: 12px; grid-row: span 2; }
  .principle-top span:last-child { font-size: 10px; }
  .principle h3 { margin: 0 0 12px; font-size: 19px; }
  .principle p { font-size: 14px; }
  .game-heading { grid-template-columns: 1fr; gap: 40px; }
  .game-lockup { padding: 0; }
  .section-logo { width: 150px; height: 142px; }
  .game-type { font-size: 10px; margin-top: 20px; }
  .game-intro-copy h2 { font-size: 32px; }
  .game-intro-copy .lead { margin-top: 20px; }
  .game-explorer { margin-top: 38px; }
  .chapter-tabs { justify-content: space-between; gap: 12px; }
  .chapter-tabs button { gap: 7px; font-size: 14px; padding: 18px 0; }
  .chapter-tabs button span { font-size: 10px; }
  .chapter-panel { grid-template-columns: 1fr; gap: 26px; padding-top: 35px; min-height: 400px; align-content: start; }
  .chapter-index { padding: 0; display: flex; align-items: end; gap: 25px; }
  .chapter-number { font-size: 62px; }
  .chapter-english { font-size: 10px; margin: 0 0 10px; }
  .chapter-copy h3 { font-size: 23px; margin-bottom: 18px; max-width: none; }
  .chapter-copy > p { font-size: 14px; }
  .chapter-detail { font-size: 13px; padding-top: 18px; margin-top: 22px; }
  .game-note { font-size: 11px; margin-top: 25px; }
  .tech-sequence { grid-template-columns: 1fr; margin-top: 45px; }
  .tech-item, .tech-item + .tech-item { border-left: 0; padding: 24px 0; gap: 28px; }
  .tech-item + .tech-item { border-top: 1px solid var(--line); }
  .tech-item p { max-width: none; }
  .roman { font-size: 32px; min-width: 50px; }
  .stages { grid-template-columns: 1fr; margin: 45px 0 55px; gap: 32px; }
  .stage h3 { margin-top: 18px; }
  .stage > p { max-width: none; }
  .records-heading { align-items: start; }
  .records-heading > span { font-size: 10px; max-width: 130px; text-align: right; }
  .record summary { grid-template-columns: 22px 1fr 20px; gap: 15px; padding: 25px 0; }
  .record-title { font-size: 17px; }
  .record-status { display: none; }
  .record-category { font-size: 10px; }
  .record-body { padding: 0 10px 25px 37px; font-size: 14px; }
  .studio-body { padding-top: 0; font-size: 15px; }
  .studio-signature { margin-top: 30px; }
  .team { grid-template-columns: 1fr; gap: 40px; margin-top: 50px; }
  .team-member img { aspect-ratio: 4 / 4.5; }
  .development-gallery { grid-template-columns: 1fr; }
  .contact { padding-bottom: 28px; }
  .contact-info { padding-bottom: 0; font-size: 15px; }
  .footer-bottom { margin-top: 60px; display: grid; grid-template-columns: 1fr auto; gap: 28px 10px; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-bottom > span { font-size: 11px; }
}
@media (max-width: 480px) {
  .brand-zh { font-size: 16px; }
  .brand-en { font-size: 8px; letter-spacing: .12em; }
  html[lang="en"] .brand-zh { font-size: 14px; max-width: 145px; }
  .header-tools { gap: 15px; }
  .language-switch { font-size: 12px; gap: 7px; }
  .menu-label { display: none; }
  .hero { padding-top: 30px; }
  .hero-center { padding: 15px 0 60px; }
  .hero-thesis { font-size: 14px; }
  .hero-bottom > span { max-width: 145px; font-size: 9px; }
  .hero-type { font-size: 10px; }
  .hero-separator { padding: 0 8px; }
}
@media (max-width: 360px) {
  :root { --gutter: 20px; }
  .chapter-tabs button { font-size: 13px; gap: 5px; }
  .chapter-panel { min-height: 460px; }
  .header-tools { gap: 12px; }
  html[lang="en"] .hero-type { max-width: 250px; margin-left: auto; margin-right: auto; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; animation: none !important; }
  .reveal-ready { opacity: 1; transform: none; }
}
@media print {
  .header, .menu-toggle, .mobile-menu, .skip-link { display: none; }
  .reveal-ready { opacity: 1; transform: none; }
  .chapter-panel[hidden] { display: grid !important; }
  .section-shell { padding: 35px; break-inside: avoid; }
  .hero { min-height: 0; }
  .hero-logo { width: 300px; }
}

.media-carousel { margin-top: 64px; }
.media-heading { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 22px; }
.media-heading h3 { font-size: 17px; font-weight: 400; }
.media-frame { aspect-ratio: 16 / 9; border: 1px solid var(--line); position: relative; display: grid; place-items: center; overflow: hidden; background: #fff; }
.media-frame img, .media-frame video { width: 100%; height: 100%; object-fit: contain; position: absolute; inset: 0; background: #fff; }
.media-placeholder { text-align: center; padding: 24px; }
.media-placeholder p:first-child { font-size: clamp(22px,3vw,38px); letter-spacing: .08em; }
.media-placeholder p:last-child { font-size: 12px; margin-top: 18px; }
.media-play { position: relative; background: #fff; border: 1px solid #000; padding: 14px 24px; z-index: 1; }
.media-slide figcaption { font-size: 13px; padding-top: 14px; }
.media-dots { position: absolute; bottom: 8px; left: 50%; transform: translateX(-50%); z-index: 2; display: flex; justify-content: center; gap: 8px; margin: 0; padding: 0 6px; background: #fff; border-radius: 20px; }
.contact-email { display: block; overflow-wrap: anywhere; }
@media (max-width: 760px) { .media-carousel { margin-top: 45px; } .media-frame { aspect-ratio: 4 / 3; } .media-placeholder p:last-child { max-width: 220px; } }
@media (max-width: 760px) { .media-heading { flex-wrap: wrap; gap: 14px; } }
/* Optical alignment of the asymmetric brand mark on narrow screens. */
@media (max-width: 760px) { .hero-logo { transform: translateX(12px); } }
/* Keep the desktop navigation on the same axis as the hero copy. */
@media (min-width: 851px) {
  .header { display: grid; grid-template-columns: minmax(0, 1fr) auto minmax(0, 1fr); }
  .header-tools { justify-self: end; }
  .hero-logo { transform: translateX(20px); }
}
.hero-thesis { text-indent: .12em; }
html[lang="en"] .hero-thesis { text-indent: .015em; }

.media-arrow { position: absolute; top: 50%; transform: translateY(-50%); z-index: 2; width: 42px; height: 48px; padding: 0; border: 0; background: #fff; font-size: 32px; line-height: 1; border-radius: 24px; font-weight: 300; }
.media-previous { left: 12px; }
.media-next { right: 12px; }
.media-arrow:hover { background: #fff; }
.media-dots button { width: 32px; height: 36px; padding: 0; border: 0; background: transparent; font-size: 8px; line-height: 36px; text-align: center; }
.media-dots button[aria-current="true"] { font-size: 14px; font-variant-numeric: tabular-nums; }
@media (max-width: 760px) { .media-arrow { width: 32px; height: 40px; font-size: 28px; } .media-previous { left: 6px; } .media-next { right: 6px; } }

.hero-download { margin-top: 22px; font-size: 13px; }

.hero-pdf-links{display:flex;justify-content:center;gap:24px;flex-wrap:wrap}