*{box-sizing:border-box}
:root{
  --bg:#f5f5f7;--surface:rgba(255,255,255,.86);--text:#1d1d1f;--muted:#6e6e73;
  --subtle:#86868b;--line:rgba(0,0,0,.11);--line-soft:rgba(0,0,0,.07);--blue:#0066cc;
  --header-h:54px;--content:1160px
}
html{scroll-behavior:smooth;scroll-padding-top:76px}
body{margin:0;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","Helvetica Neue",Arial,sans-serif;line-height:1.5;-webkit-font-smoothing:antialiased}
body.menu-open{overflow:hidden}
a{color:inherit;text-decoration:none} button{font:inherit}
.topbar{position:fixed;inset:0 0 auto;z-index:1000;height:var(--header-h)}
.topbar:before{content:"";position:absolute;inset:0;background:rgba(250,250,252,.74);backdrop-filter:saturate(180%) blur(18px);-webkit-backdrop-filter:saturate(180%) blur(18px);border-bottom:1px solid transparent;z-index:-1;transition:.2s}
.topbar.scrolled:before,.topbar.menu-active:before{background:rgba(250,250,252,.92);border-color:var(--line-soft)}
.nav-shell{width:min(var(--content),calc(100% - 40px));height:var(--header-h);margin:auto;display:grid;grid-template-columns:1fr auto 1fr;align-items:center}
.nav-side{display:flex;align-items:center}.nav-side-left{justify-content:flex-start}.nav-side-right{justify-content:flex-end}
.zb-logo{width:38px;height:30px;display:grid;place-items:center;border:1px solid rgba(0,0,0,.16);border-radius:9px;background:rgba(255,255,255,.64);font-size:12px;font-weight:700;transition:.2s}
.zb-logo:hover{background:#fff;transform:translateY(-1px);border-color:rgba(0,0,0,.26)}
.nav-center{height:100%;display:flex;align-items:center;gap:34px}.nav-item{height:100%;display:flex;align-items:center}
.nav-link,.language-toggle{font-size:12px;color:#333336}.nav-link{height:100%;display:flex;align-items:center}.nav-link:hover,.language-toggle:hover{color:#000}
.language-toggle{border:0;background:transparent;cursor:pointer;padding:10px 0 10px 12px}
.mega-panel{position:absolute;top:var(--header-h);left:0;width:100%;background:rgba(250,250,252,.98);backdrop-filter:blur(24px);-webkit-backdrop-filter:blur(24px);border-bottom:1px solid var(--line-soft);overflow:hidden;max-height:0;opacity:0;pointer-events:none;transition:max-height .3s cubic-bezier(.22,.61,.36,1),opacity .18s}
.mega-panel.open{max-height:590px;opacity:1;pointer-events:auto}
.mega-inner{width:min(960px,calc(100% - 40px));margin:auto;padding:34px 0 42px}.mega-content{display:none}.mega-content.active{display:block}
.mega-kicker{margin:0 0 18px;color:var(--subtle);font-size:12px}.mega-columns{display:grid;grid-template-columns:1.1fr .9fr;gap:80px}
.mega-title{display:inline-block;font-size:30px;line-height:1.05;letter-spacing:-.04em;font-weight:650;margin-bottom:10px}
.mega-columns p{max-width:520px;color:var(--muted);font-size:15px;margin:0}.mega-mini{display:flex;flex-direction:column;gap:8px;padding-top:3px;font-size:15px;font-weight:550}.mega-mini a:hover{text-decoration:underline}
.education-menu-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));column-gap:56px}.edu-menu-row{padding:13px 0 16px;display:grid;gap:2px;border-bottom:1px solid var(--line-soft)}
.edu-menu-row strong{font-size:17px;letter-spacing:-.02em}.edu-menu-row span{color:var(--muted);font-size:13px}.edu-menu-row small{color:var(--subtle);font-size:11px;margin-top:2px}
.coming-soon{min-height:86px;display:flex;align-items:center;gap:12px;color:var(--muted)}.soft-dot{width:9px;height:9px;border-radius:50%;background:#c7c7cc}
.page-dim{position:fixed;inset:var(--header-h) 0 0;background:rgba(0,0,0,.18);opacity:0;pointer-events:none;z-index:800;transition:.18s}.page-dim.active{opacity:1}.mobile-nav,.mobile-menu{display:none}

.home-page{overflow:hidden}.home-hero{height:100vh;min-height:620px;padding:calc(var(--header-h) + 40px) 24px 42px;display:flex;align-items:center;justify-content:center;background:radial-gradient(circle at 50% 24%,rgba(255,255,255,.98),rgba(245,245,247,.45) 38%,rgba(245,245,247,0) 66%),linear-gradient(180deg,#fbfbfd,#f5f5f7)}
.hero-inner{text-align:center;width:min(980px,100%);transform:translateY(-2vh)}.hero-kicker{margin:0 0 18px;color:var(--muted);font-size:17px}.hero-inner h1{margin:0;font-size:clamp(62px,9vw,118px);line-height:.94;letter-spacing:-.07em;font-weight:650}
.hero-line{margin:28px auto 0;font-size:clamp(22px,3vw,34px);line-height:1.18;letter-spacing:-.035em;color:#3a3a3c;font-weight:500}.text-link{display:inline-flex;gap:9px;align-items:center;margin-top:28px;color:var(--blue);font-size:17px}.text-link:hover{text-decoration:underline}

.subpage{padding-top:var(--header-h)}.page-hero{width:min(var(--content),calc(100% - 48px));margin:auto;padding:120px 0 92px}.page-kicker{margin:0 0 16px;color:var(--muted);font-size:15px;font-weight:600}.page-hero h1,.placeholder-page h1{margin:0;max-width:920px;font-size:clamp(54px,7vw,90px);line-height:.96;letter-spacing:-.06em;font-weight:650}
.page-deck{max-width:790px;margin:32px 0 0;color:#3a3a3c;font-size:clamp(20px,2.2vw,28px);line-height:1.48;letter-spacing:-.02em}
.article-shell{width:min(var(--content),calc(100% - 48px));margin:auto}.lead-story{max-width:820px;margin-left:100px;padding:10px 0 100px}
.lead-story p{font-size:20px;line-height:1.65;letter-spacing:-.015em}.pullquote{font-size:clamp(34px,4vw,52px)!important;line-height:1.06!important;font-weight:650;letter-spacing:-.045em!important;margin:42px 0 28px!important}.emphasis{font-weight:620}
.story-block{display:grid;grid-template-columns:60px 300px minmax(0,1fr);gap:30px;padding:58px 0 68px;border-top:1px solid var(--line)}.story-label{padding-top:8px;color:var(--subtle);font-size:13px}
.story-title h2{margin:0;font-size:31px;line-height:1.08;letter-spacing:-.04em;font-weight:620}.story-copy{max-width:630px}.story-copy p{margin:0 0 18px;color:#3a3a3c;font-size:17px;line-height:1.66;letter-spacing:-.012em}
.inline-question,.ending-line{color:var(--text)!important;font-size:22px!important;line-height:1.38!important;font-weight:600!important;letter-spacing:-.025em!important;margin-top:30px!important}.final-block{padding-bottom:120px}

.education-hero{padding-bottom:74px}.education-page-list{width:min(var(--content),calc(100% - 48px));margin:auto;border-top:1px solid var(--line);padding-bottom:120px}
.education-card{display:grid;grid-template-columns:190px 1fr;gap:40px;padding:46px 0 50px;border-bottom:1px solid var(--line)}
.education-date{color:var(--subtle);font-size:14px;padding-top:8px}.education-level{margin:0 0 10px;color:var(--muted);font-size:14px;font-weight:600}.education-card h2{margin:0;font-size:clamp(32px,4vw,52px);line-height:1.02;letter-spacing:-.045em;font-weight:620}.education-programme{margin:14px 0 0;color:#3a3a3c;font-size:19px}
.placeholder-page{width:min(var(--content),calc(100% - 48px));margin:auto;min-height:calc(100vh - var(--header-h) - 150px);padding:150px 0}.placeholder-page p:last-child{color:var(--muted);font-size:18px;margin-top:24px}
.site-footer{width:min(var(--content),calc(100% - 48px));margin:auto;padding:34px 0 46px;border-top:1px solid var(--line);display:grid;grid-template-columns:1fr auto 1fr;align-items:center;color:var(--subtle);font-size:12px}.site-footer p{margin:0}.site-footer p:last-child{justify-self:end}.footer-logo{width:32px;height:26px;font-size:10px}

@media(max-width:820px){
:root{--header-h:52px}.desktop-nav,.mega-panel{display:none!important}.mobile-nav{display:grid;grid-template-columns:1fr auto 1fr;width:calc(100% - 28px)}.mobile-side{display:flex;align-items:center}.mobile-side-left{justify-content:flex-start}.mobile-side-right{justify-content:flex-end}.mobile-logo{justify-self:center}
.menu-button{width:36px;height:36px;display:flex;flex-direction:column;justify-content:center;gap:5px;border:0;background:transparent;padding:0;cursor:pointer}.menu-button span{width:16px;height:1.5px;background:#1d1d1f;transition:.2s}.menu-button.active span:first-child{transform:translateY(3.25px) rotate(45deg)}.menu-button.active span:last-child{transform:translateY(-3.25px) rotate(-45deg)}
.mobile-menu{display:block;position:fixed;top:var(--header-h);left:0;width:100%;height:calc(100vh - var(--header-h));background:rgba(250,250,252,.99);backdrop-filter:blur(24px);-webkit-backdrop-filter:blur(24px);transform:translateY(-104%);opacity:0;transition:.3s;z-index:900;pointer-events:none}.mobile-menu.open{transform:translateY(0);opacity:1;pointer-events:auto}.mobile-menu-inner{padding:34px 26px;display:flex;flex-direction:column}.mobile-menu a{padding:17px 0;font-size:30px;line-height:1.05;letter-spacing:-.04em;font-weight:620;border-bottom:1px solid var(--line-soft)}
.page-dim{display:none}.home-hero{padding-left:20px;padding-right:20px}.hero-inner{transform:translateY(-4vh)}.hero-inner h1{font-size:clamp(58px,17vw,86px)}.hero-line{font-size:24px}.page-hero,.article-shell,.education-page-list,.site-footer,.placeholder-page{width:calc(100% - 36px)}.page-hero{padding:88px 0 64px}.page-hero h1,.placeholder-page h1{font-size:clamp(44px,12vw,66px)}.page-deck{font-size:20px}.lead-story{margin-left:0;padding-bottom:76px}.lead-story p{font-size:18px}.story-block{grid-template-columns:1fr;gap:14px;padding:42px 0 50px}.story-label{padding:0}.story-title h2{font-size:29px}.story-copy{max-width:none}.education-card{grid-template-columns:1fr;gap:13px;padding:34px 0 38px}.education-card h2{font-size:32px}.site-footer{grid-template-columns:auto 1fr;gap:15px}.site-footer p:nth-child(2){justify-self:end}.site-footer p:last-child{display:none}.placeholder-page{padding:110px 0}
}
@media(max-width:520px){.hero-kicker{font-size:15px}.text-link{font-size:16px}.story-title h2{font-size:27px}.story-copy p{font-size:16px}.education-card h2{font-size:28px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{transition-duration:.01ms!important}}


/* ===== V4 About page: viewport-first hero + floating topic cards ===== */
.about-page {
  padding-top: var(--header-h);
}

.about-hero {
  min-height: calc(100svh - var(--header-h));
  display: flex;
  align-items: center;
  background:
    radial-gradient(circle at 18% 12%, rgba(255,255,255,.98), rgba(255,255,255,0) 34%),
    radial-gradient(circle at 84% 18%, rgba(226,234,255,.66), rgba(226,234,255,0) 33%),
    linear-gradient(180deg,#fafafd 0%,#f3f4f7 100%);
  border-bottom: 1px solid var(--line-soft);
}

.about-hero-inner {
  width: min(1100px, calc(100% - 48px));
  margin: 0 auto;
  padding: clamp(34px, 5vh, 72px) 0;
}

.about-hero .page-kicker {
  margin-bottom: 10px;
}

.about-hero h1 {
  margin: 0;
  max-width: 880px;
  font-size: clamp(48px, 5.5vw, 82px);
  line-height: .98;
  letter-spacing: -.055em;
  font-weight: 650;
}

.about-hero-deck {
  max-width: 790px;
  margin: clamp(16px, 2.3vh, 28px) 0 0;
  color: #3a3a3c;
  font-size: clamp(18px, 1.45vw, 24px);
  line-height: 1.45;
  letter-spacing: -.018em;
}

.about-opening-card {
  width: min(920px, 100%);
  margin-top: clamp(22px, 3.8vh, 42px);
  padding: clamp(20px, 2.5vw, 32px);
  border: 1px solid rgba(0,0,0,.08);
  border-radius: 26px;
  background: rgba(255,255,255,.72);
  box-shadow: 0 22px 70px rgba(0,0,0,.07);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.about-opening-card > p {
  margin: 0;
  color: #3a3a3c;
  font-size: clamp(15px, 1.1vw, 18px);
  line-height: 1.58;
}

.opening-bottom {
  margin-top: 20px;
  padding-top: 18px;
  border-top: 1px solid var(--line-soft);
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 30px;
}

.opening-question,
.opening-judgment {
  margin: 0;
}

.opening-question {
  font-size: clamp(24px, 2.25vw, 34px);
  line-height: 1.08;
  letter-spacing: -.04em;
  font-weight: 650;
}

.opening-judgment {
  max-width: 340px;
  color: var(--muted);
  text-align: right;
  font-size: 14px;
  line-height: 1.45;
}

.about-explore {
  width: min(1260px, 100%);
  margin: 0 auto;
  padding: clamp(70px, 9vw, 124px) 0 120px;
  overflow: hidden;
}

.about-explore-head {
  width: min(1100px, calc(100% - 48px));
  margin: 0 auto 34px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
}

.about-explore-head h2 {
  margin: 0;
  max-width: 740px;
  font-size: clamp(38px, 4.8vw, 66px);
  line-height: 1;
  letter-spacing: -.052em;
  font-weight: 650;
}

.rail-controls {
  display: flex;
  gap: 10px;
}

.rail-arrow {
  width: 40px;
  height: 40px;
  border: 0;
  border-radius: 50%;
  background: #e6e6e9;
  color: #1d1d1f;
  cursor: pointer;
  font-size: 19px;
  transition: transform .18s ease, background .18s ease;
}

.rail-arrow:hover {
  background: #d8d8dd;
  transform: scale(1.04);
}

.about-card-rail {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(320px, 31vw);
  gap: 18px;
  overflow-x: auto;
  overscroll-behavior-inline: contain;
  scroll-snap-type: inline mandatory;
  scroll-padding-inline: max(24px, calc((100vw - 1100px)/2));
  padding: 10px max(24px, calc((100vw - 1100px)/2)) 28px;
  scrollbar-width: none;
}

.about-card-rail::-webkit-scrollbar { display: none; }

.about-topic-card {
  position: relative;
  min-height: clamp(400px, 55vh, 570px);
  scroll-snap-align: start;
  border: 0;
  border-radius: 30px;
  padding: 28px;
  overflow: hidden;
  text-align: left;
  cursor: pointer;
  color: #fff;
  box-shadow: 0 20px 52px rgba(0,0,0,.12);
  transition: transform .22s ease, box-shadow .22s ease;
}

.about-topic-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 28px 72px rgba(0,0,0,.16);
}

.about-topic-card::before,
.about-topic-card::after {
  content:"";
  position:absolute;
  border-radius:50%;
  filter: blur(2px);
  opacity:.9;
}

.about-topic-card::before {
  width: 260px;
  height: 260px;
  right: -80px;
  top: -60px;
  background: rgba(255,255,255,.18);
}

.about-topic-card::after {
  width: 180px;
  height: 180px;
  left: -70px;
  bottom: -65px;
  background: rgba(255,255,255,.10);
}

.card-unknown { background: linear-gradient(145deg,#161719 0%,#31343a 60%,#5a6470 100%); }
.card-network { background: linear-gradient(145deg,#2544a6 0%,#4e71df 52%,#96b4ff 100%); }
.card-model { background: linear-gradient(145deg,#4b2b79 0%,#8d58ba 54%,#d0a6e5 100%); }
.card-people { background: linear-gradient(145deg,#175c5d 0%,#2c8c83 54%,#95d2bf 100%); }
.card-self { background: linear-gradient(145deg,#5b2f2f 0%,#9d594f 56%,#e5aa91 100%); }

.topic-index {
  position: relative;
  z-index: 1;
  display: inline-flex;
  width: 34px;
  height: 34px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  background: rgba(255,255,255,.14);
  border: 1px solid rgba(255,255,255,.22);
  font-size: 12px;
  font-weight: 650;
}

.topic-copy {
  position: absolute;
  z-index: 1;
  left: 28px;
  right: 28px;
  bottom: 28px;
}

.topic-copy h3 {
  margin: 0;
  font-size: clamp(28px, 2.6vw, 42px);
  line-height: 1;
  letter-spacing: -.045em;
  font-weight: 650;
}

.topic-copy p {
  margin: 16px 0 0;
  max-width: 92%;
  color: rgba(255,255,255,.78);
  font-size: 15px;
  line-height: 1.5;
}

.card-link {
  display: inline-block;
  margin-top: 22px;
  color: #fff;
  font-size: 14px;
  font-weight: 600;
}

.about-closing {
  width: min(860px, calc(100% - 48px));
  margin: 0 auto;
  padding: 0 0 110px;
  color: var(--muted);
  font-size: 18px;
  line-height: 1.6;
}

.topic-dialog-layer {
  position: fixed;
  inset: 0;
  z-index: 1800;
  display: none;
}

.topic-dialog-layer.open {
  display: block;
}

.topic-dialog-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(0,0,0,.64);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  animation: dialogFade .18s ease both;
}

.topic-dialog {
  position: absolute;
  left: 50%;
  top: 50%;
  width: min(970px, calc(100% - 64px));
  max-height: min(82svh, 820px);
  transform: translate(-50%, -50%);
  overflow: auto;
  display: none;
  background: #1d1d1f;
  color: #f5f5f7;
  border-radius: 30px;
  padding: clamp(34px, 4.5vw, 62px);
  box-shadow: 0 34px 110px rgba(0,0,0,.42);
  animation: dialogUp .24s cubic-bezier(.22,.61,.36,1) both;
  overscroll-behavior: contain;
}

.topic-dialog.active {
  display: block;
}

.dialog-close {
  position: sticky;
  float: right;
  top: 0;
  z-index: 2;
  width: 38px;
  height: 38px;
  border: 0;
  border-radius: 50%;
  background: #424245;
  color: #fff;
  cursor: pointer;
  font-size: 26px;
  line-height: 1;
}

.dialog-head {
  max-width: 760px;
  padding-right: 52px;
}

.dialog-head .topic-index {
  margin-bottom: 24px;
}

.dialog-head h2 {
  margin: 0;
  font-size: clamp(40px, 5vw, 68px);
  line-height: .98;
  letter-spacing: -.055em;
  font-weight: 650;
}

.dialog-copy {
  max-width: 760px;
  margin-top: 36px;
}

.dialog-copy p {
  margin: 0 0 20px;
  color: #d2d2d7;
  font-size: clamp(16px, 1.45vw, 19px);
  line-height: 1.65;
}

.dialog-copy .inline-question,
.dialog-copy .ending-line {
  color: #fff !important;
}

@keyframes dialogFade {
  from { opacity:0; }
  to { opacity:1; }
}

@keyframes dialogUp {
  from { opacity:0; transform:translate(-50%,-47%) scale(.985); }
  to { opacity:1; transform:translate(-50%,-50%) scale(1); }
}

/* 16:9 and 16:10 desktop tuning: first view should fit */
@media (min-width: 900px) and (max-height: 900px) {
  .about-hero-inner {
    padding-top: clamp(24px, 3.2vh, 40px);
    padding-bottom: clamp(24px, 3.2vh, 40px);
  }
  .about-hero h1 {
    font-size: clamp(44px, 5.1vw, 72px);
  }
  .about-hero-deck {
    margin-top: 14px;
    font-size: clamp(17px, 1.3vw, 21px);
  }
  .about-opening-card {
    margin-top: 20px;
    padding: 22px 26px;
  }
  .about-opening-card > p {
    font-size: 15px;
    line-height: 1.48;
  }
  .opening-bottom {
    margin-top: 15px;
    padding-top: 14px;
  }
  .opening-question {
    font-size: clamp(22px, 2vw, 30px);
  }
}

/* common 16:9 wide screens */
@media (min-width: 1200px) and (min-aspect-ratio: 16/10) {
  .about-card-rail {
    grid-auto-columns: minmax(340px, 29vw);
  }
}

/* phones: designed around tall 18:9–20:9 screens */
@media (max-width: 820px) {
  .about-hero {
    min-height: calc(100svh - var(--header-h));
    align-items: flex-start;
  }

  .about-hero-inner {
    width: calc(100% - 36px);
    padding: clamp(42px, 7svh, 72px) 0 36px;
  }

  .about-hero h1 {
    font-size: clamp(44px, 13vw, 66px);
  }

  .about-hero-deck {
    font-size: 18px;
  }

  .about-opening-card {
    border-radius: 22px;
    padding: 20px;
  }

  .about-opening-card > p {
    font-size: 15px;
  }

  .opening-bottom {
    display: block;
  }

  .opening-judgment {
    margin-top: 12px;
    text-align: left;
    max-width: none;
  }

  .about-explore {
    padding-top: 76px;
    padding-bottom: 84px;
  }

  .about-explore-head {
    width: calc(100% - 36px);
    margin-bottom: 26px;
  }

  .about-explore-head h2 {
    font-size: 42px;
  }

  .rail-controls {
    display: none;
  }

  .about-card-rail {
    grid-auto-columns: 84vw;
    gap: 14px;
    padding-left: 18px;
    padding-right: 18px;
    scroll-padding-inline: 18px;
  }

  .about-topic-card {
    min-height: min(64svh, 560px);
    border-radius: 26px;
    padding: 24px;
  }

  .topic-copy {
    left: 24px;
    right: 24px;
    bottom: 24px;
  }

  .topic-copy h3 {
    font-size: clamp(30px, 8.5vw, 42px);
  }

  .topic-dialog {
    width: calc(100% - 22px);
    max-height: calc(100svh - 22px);
    border-radius: 24px;
    padding: 28px 22px 34px;
  }

  .dialog-head {
    padding-right: 36px;
  }

  .dialog-head h2 {
    font-size: 42px;
  }

  .about-closing {
    width: calc(100% - 36px);
    font-size: 16px;
    padding-bottom: 82px;
  }
}

@media (max-width: 820px) and (min-aspect-ratio: 9/19) {
  .about-hero-inner {
    padding-top: 36px;
  }
}

body.dialog-open {
  overflow: hidden;
}