:root {
  --ink: #17324d;
  --deep: #0d2e4a;
  --deep-soft: #1b5077;
  --paper: #fcfdfe;
  --cream: #f1f6fa;
  --muted: #64788b;
  --line: rgba(23, 50, 77, 0.15);
  --line-light: rgba(252, 253, 254, 0.2);
  --accent: #4f9fef;
  --accent-dark: #2469a4;
  --sans: "Manrope", "Noto Sans SC", sans-serif;
  --mono: "DM Mono", monospace;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { margin: 0; color: var(--ink); background: var(--paper); font-family: var(--sans); font-size: 16px; line-height: 1.6; }
a { color: inherit; text-decoration: none; }
.container { width: min(1180px, calc(100% - 96px)); margin: 0 auto; }
.section-dark { color: var(--paper); background: var(--deep); }
.section-light { background: var(--paper); }
.section-cream { background: var(--cream); }

.site-header { position: absolute; z-index: 5; width: 100%; color: var(--paper); background: rgba(13, 46, 74, 0.95); }
.utility-bar { border-bottom: 1px solid rgba(252, 253, 254, 0.12); color: rgba(252, 253, 254, 0.54); font-family: var(--mono); font-size: 9px; letter-spacing: 0.04em; }
.utility-wrap { display: flex; justify-content: space-between; gap: 20px; min-height: 32px; align-items: center; }
.nav-wrap { display: flex; align-items: center; justify-content: space-between; min-height: 84px; border-bottom: 1px solid var(--line-light); }
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: 20px; font-weight: 800; letter-spacing: -0.06em; }
.brand-logo-image { display: block; width: 70px; height: 70px; object-fit: contain; }
.brand-copy { display: flex; flex-direction: column; gap: 1px; }
.brand-copy strong { line-height: 1.15; }
.brand-copy small { font-size: 8px; font-weight: 500; letter-spacing: 0.04em; line-height: 1.25; }
.brand-team { color: rgba(252, 253, 254, 0.55); }
.brand-accent { color: var(--accent); }
.brand-mark { display: inline-flex; align-items: end; gap: 3px; height: 22px; }
.brand-mark i { display: block; width: 4px; background: var(--accent); border-radius: 4px; transform: skew(-16deg); }
.brand-mark i:nth-child(1) { height: 11px; }
.brand-mark i:nth-child(2) { height: 18px; }
.brand-mark i:nth-child(3) { height: 14px; }
.main-nav { display: flex; gap: 25px; margin-left: 30px; font-size: 12px; font-weight: 600; }
.main-nav a { position: relative; color: rgba(252, 253, 254, 0.66); transition: color 0.2s ease; white-space: nowrap; }
.main-nav a:hover, .main-nav a.active { color: var(--paper); }
.main-nav a.active::after { position: absolute; right: 0; bottom: -31px; left: 0; height: 2px; background: var(--accent); content: ""; }
.main-nav .nav-platform { color: var(--accent); }
.main-nav .nav-platform:hover { color: var(--paper); }
.header-actions { display: flex; align-items: center; gap: 17px; margin-left: 25px; }
.language-switch { color: rgba(252, 253, 254, 0.7); font-family: var(--mono); font-size: 10px; white-space: nowrap; }
.language-switch span { margin: 0 3px; color: rgba(252, 253, 254, 0.3); }
.header-search { display: grid; width: 28px; height: 28px; border: 1px solid rgba(252, 253, 254, 0.34); border-radius: 50%; place-items: center; font-size: 19px; line-height: 1; }
.nav-contact { display: inline-flex; gap: 9px; align-items: center; padding: 10px 13px; border: 1px solid rgba(79, 159, 239, 0.8); color: var(--paper); font-size: 11px; font-weight: 700; white-space: nowrap; }
.nav-contact span, .card-arrow, .notice-list b { color: var(--accent); }

.hero { position: relative; min-height: 720px; overflow: hidden; }
.hero-grid { position: absolute; inset: 0; opacity: 0.4; background-image: linear-gradient(var(--line-light) 1px, transparent 1px), linear-gradient(90deg, var(--line-light) 1px, transparent 1px); background-position: center; background-size: 86px 86px; mask-image: linear-gradient(to right, transparent, #000 22%, #000 80%, transparent); }
.hero-slider { position: relative; min-height: 670px; }
.hero-slide { position: absolute; inset: 0; z-index: 0; opacity: 0; pointer-events: none; transform: translateY(12px); transition: opacity 0.7s ease, transform 0.7s ease; }
.hero-slide.is-active { z-index: 1; opacity: 1; pointer-events: auto; transform: translateY(0); }
.hero-content { position: relative; display: grid; grid-template-columns: 1fr; min-height: 670px; align-items: center; padding-top: 80px; }
.hero-copy { display: none; }
.eyebrow { margin: 0 0 20px; color: var(--accent); font-family: var(--mono); font-size: 11px; letter-spacing: 0.15em; text-transform: uppercase; }
.eyebrow-dark { color: var(--accent-dark); }
.hero h1, h2 { margin: 0; font-weight: 700; letter-spacing: -0.075em; line-height: 1.1; }
.hero h1 { font-size: clamp(52px, 6vw, 84px); }
.hero h1 em { color: var(--accent); font-style: normal; }
.hero-text { max-width: 430px; margin: 32px 0 38px; color: rgba(252, 253, 254, 0.68); font-size: 15px; line-height: 2; }
.hero-actions { display: flex; align-items: center; gap: 28px; }
.button { display: inline-flex; align-items: center; justify-content: space-between; gap: 34px; min-width: 192px; padding: 15px 18px; font-size: 12px; font-weight: 700; transition: transform 0.2s ease, background 0.2s ease; }
.button:hover { transform: translateY(-3px); }
.button-primary { color: var(--ink); background: var(--accent); }
.button-dark { color: var(--paper); background: var(--deep); }
.button span { font-size: 17px; }
.text-link { display: inline-flex; align-items: center; gap: 11px; padding-bottom: 3px; border-bottom: 1px solid currentColor; font-size: 12px; font-weight: 700; }
.text-link span { font-size: 17px; font-weight: 400; transition: transform 0.2s ease; }
.text-link:hover span { transform: translateX(4px); }
.light-link { color: var(--paper); }
.dark-link { color: var(--ink); }
.hero-visual { position: relative; width: min(760px, 100%); height: 560px; margin: 0 auto; }
.hero-earth-placeholder { position: absolute; top: 45px; left: 50%; width: min(470px, 74%); aspect-ratio: 1; border-radius: 50%; transform: translateX(-50%); background: radial-gradient(circle at 34% 28%, #6a9bc4, var(--deep-soft) 42%, #08233d 75%); box-shadow: 0 0 0 1px rgba(79, 159, 239, 0.24), 0 0 100px rgba(79, 159, 239, 0.16); }
.image-placeholder { position: relative; display: grid; place-content: center; min-height: 180px; overflow: hidden; color: #71879a; background-color: #dfeaf3; background-image: linear-gradient(135deg, rgba(255,255,255,0.32) 25%, transparent 25%, transparent 50%, rgba(255,255,255,0.32) 50%, rgba(255,255,255,0.32) 75%, transparent 75%); background-size: 36px 36px; text-align: center; }
.image-placeholder::before, .image-placeholder::after { position: absolute; width: 30px; height: 30px; border-color: rgba(23, 50, 77, 0.24); content: ""; }
.image-placeholder::before { top: 12px; left: 12px; border-top: 1px solid; border-left: 1px solid; }
.image-placeholder::after { right: 12px; bottom: 12px; border-right: 1px solid; border-bottom: 1px solid; }
.image-placeholder span { font-size: 13px; font-weight: 700; letter-spacing: 0.04em; }
.image-placeholder small { margin-top: 3px; color: #6f879b; font-family: var(--mono); font-size: 9px; letter-spacing: 0.12em; }
.image-placeholder-dark { color: rgba(252, 253, 254, 0.66); background-color: transparent; background-image: radial-gradient(circle at center, rgba(79,159,239,0.16) 1px, transparent 1px); background-size: 12px 12px; }
.image-placeholder-dark::before, .image-placeholder-dark::after { border-color: rgba(79, 159, 239, 0.42); }
.image-placeholder-dark small { color: rgba(79, 159, 239, 0.7); }
.hero-orbit { position: absolute; top: 93px; left: 50%; width: min(580px, 94%); aspect-ratio: 1; border: 1px solid rgba(79, 159, 239, 0.28); border-radius: 50%; transform: translateX(-50%) rotate(-32deg) scaleY(0.42); }
.orbit-two { top: 80px; left: 50%; transform: translateX(-50%) rotate(38deg) scaleY(0.35); border-color: rgba(252, 253, 254, 0.16); }
.hero-stat { position: absolute; display: flex; flex-direction: column; gap: 3px; font-family: var(--mono); }
.hero-stat strong { color: var(--accent); font-size: 26px; font-weight: 400; line-height: 1; }
.hero-stat span { color: rgba(252,253,254,0.58); font-size: 9px; letter-spacing: 0.08em; }
.stat-top { top: 95px; right: 3%; }
.stat-bottom { bottom: 50px; left: 50%; text-align: center; transform: translateX(-50%); }
.hero-footer { position: absolute; right: 0; bottom: 34px; left: 0; display: flex; align-items: center; gap: 15px; color: rgba(252,253,254,0.48); font-family: var(--mono); font-size: 9px; letter-spacing: 0.14em; }
.scroll-line { width: 84px; height: 1px; background: var(--accent); }
.hero-dots { position: absolute; bottom: 0; left: 50%; display: flex; align-items: center; gap: 10px; transform: translateX(-50%); }
.hero-dot { width: 8px; height: 8px; padding: 0; border: 0; border-radius: 50%; background: rgba(252, 253, 254, 0.42); cursor: pointer; transition: width 0.25s ease, background 0.25s ease, transform 0.25s ease; }
.hero-dot:hover { transform: scale(1.35); background: rgba(252, 253, 254, 0.78); }
.hero-dot.is-active { width: 24px; border-radius: 8px; background: var(--accent); }

.intro { padding: 140px 0 150px; }
.intro-grid, .notice-grid { display: grid; grid-template-columns: 190px 1fr; gap: 80px; }
.section-kicker { display: flex; align-items: center; gap: 12px; color: var(--muted); font-family: var(--mono); font-size: 10px; letter-spacing: 0.12em; }
.kicker-line { width: 30px; height: 1px; background: var(--accent-dark); }
.intro-content { max-width: 810px; }
h2 { font-size: clamp(42px, 5vw, 68px); }
h2 span { color: #6b8aa6; }
.intro-bottom { display: grid; grid-template-columns: minmax(0, 1fr) max-content; align-items: end; gap: 52px; margin-top: 48px; }
.intro-copy-column { display: grid; grid-template-columns: 1fr; gap: 22px; max-width: 680px; }
.intro-bottom p { margin: 0; color: #5e7489; font-size: 14px; line-height: 2; }
.intro-link { display: inline-flex; align-items: center; width: max-content; margin-bottom: 2px; white-space: nowrap; writing-mode: horizontal-tb; }

.research { padding: 122px 0 138px; }
.section-heading { display: grid; grid-template-columns: 190px 1fr auto; gap: 80px; align-items: end; margin-bottom: 64px; }
.directions { padding: 122px 0 138px; }
.directions-heading { align-items: start; }
.direction-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.direction-card { position: relative; min-height: 350px; padding: 27px 23px 25px; border: 1px solid var(--line); background: #fff; }
.direction-card-featured { border-color: rgba(79, 159, 239, 0.55); background: #eaf4fc; }
.direction-index { color: var(--accent-dark); font-family: var(--mono); font-size: 12px; }
.direction-card h3 { margin: 47px 0 17px; font-size: clamp(20px, 2vw, 25px); letter-spacing: -0.06em; line-height: 1.35; }
.direction-card p { max-width: 270px; margin: 0 0 25px; color: var(--muted); font-size: 11px; line-height: 1.85; }
.heading-link { margin-bottom: 9px; }
.research-list { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
.research-card { position: relative; }
.featured-card { padding-bottom: 26px; border-bottom: 1px solid var(--line); }
.card-image { min-height: 360px; margin-bottom: 22px; }
.card-meta { display: flex; align-items: center; gap: 17px; margin-bottom: 12px; color: var(--muted); font-family: var(--mono); font-size: 10px; }
.tag { color: var(--accent-dark); }
.card-meta time { color: #8195a7; }
.research-card h3 { max-width: 480px; margin: 0 0 11px; font-size: 22px; line-height: 1.4; letter-spacing: -0.05em; }
.research-card p { max-width: 480px; margin: 0; color: var(--muted); font-size: 13px; line-height: 1.9; }
.card-arrow { position: absolute; right: 0; bottom: 25px; display: grid; width: 38px; height: 38px; border: 1px solid var(--accent-dark); place-items: center; font-size: 18px; }
.research-side { border-top: 1px solid var(--line); }
.compact-card { display: flex; gap: 27px; padding: 26px 0; border-bottom: 1px solid var(--line); }
.compact-number { color: var(--accent-dark); font-family: var(--mono); font-size: 13px; }
.compact-copy { flex: 1; }
.compact-card h3 { margin-bottom: 13px; font-size: 18px; }

.members { padding: 136px 0 144px; }
.members-heading { align-items: start; }
.heading-note { max-width: 170px; margin: 12px 0 0; color: var(--muted); font-size: 12px; line-height: 1.9; }
.member-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 18px; }
.member-card { min-width: 0; }
.member-photo { min-height: 272px; }
.member-large .member-photo { min-height: 360px; }
.member-info { display: flex; justify-content: space-between; gap: 12px; padding-top: 18px; border-bottom: 1px solid var(--line); }
.member-info h3 { margin: 0; font-size: 16px; letter-spacing: -0.03em; }
.member-info p { margin: 2px 0 17px; color: var(--muted); font-size: 11px; }
.member-index { color: var(--accent-dark); font-family: var(--mono); font-size: 10px; }

.notice { padding: 128px 0 136px; }
.notice-grid { gap: 80px; }
.section-kicker-light { color: rgba(252,253,254,0.52); }
.section-kicker-light .kicker-line { background: var(--accent); }
.notice-content { max-width: 880px; }
.notice h2 { margin-bottom: 48px; color: var(--paper); }
.notice-list { border-top: 1px solid var(--line-light); margin-bottom: 32px; }
.notice-list a { display: grid; grid-template-columns: 130px 1fr 26px; gap: 22px; align-items: center; padding: 21px 0; border-bottom: 1px solid var(--line-light); font-size: 14px; transition: color 0.2s ease; }
.notice-list a:hover { color: var(--accent); }
.notice-list time { color: rgba(252,253,254,0.43); font-family: var(--mono); font-size: 10px; }

.media-strip { padding: 95px 0 112px; }
.media-strip-label { display: flex; justify-content: space-between; margin-bottom: 25px; color: var(--muted); font-family: var(--mono); font-size: 9px; letter-spacing: 0.1em; }
.media-grid { display: grid; grid-template-columns: 1.8fr 1fr 1fr; gap: 14px; }
.media-placeholder { min-height: 220px; }
.media-wide { min-height: 220px; }

.contact { padding: 145px 0 156px; text-align: center; }
.contact-inner { display: flex; flex-direction: column; align-items: center; }
.contact h2 { margin-bottom: 42px; }
.contact .button { min-width: 205px; }
.site-footer { padding: 44px 0 26px; }
.footer-top { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 30px; align-items: start; padding-bottom: 70px; }
.brand-footer { align-self: start; }
.footer-description p { margin: 0; color: rgba(252,253,254,0.48); font-size: 12px; line-height: 1.9; }
.footer-email { display: inline-block; margin-top: 14px; color: var(--accent); font-family: var(--mono); font-size: 10px; letter-spacing: 0.02em; transition: color 0.2s ease; }
.footer-email:hover { color: var(--paper); }
.footer-links { display: grid; grid-template-columns: 1fr 1fr; gap: 13px 25px; justify-self: end; width: 220px; color: rgba(252,253,254,0.55); font-size: 11px; }
.footer-links a:hover { color: var(--accent); }
.footer-bottom { display: flex; justify-content: space-between; padding-top: 17px; border-top: 1px solid var(--line-light); color: rgba(252,253,254,0.35); font-family: var(--mono); font-size: 9px; letter-spacing: 0.06em; }
.footer-bottom b { color: var(--accent); font-size: 15px; font-weight: 400; vertical-align: middle; }

@media (max-width: 900px) {
  .container { width: min(100% - 48px, 680px); }
  .main-nav { display: none; }
  .utility-wrap { min-height: 28px; }
  .header-actions { margin-left: auto; }
  .hero-slide .hero-content { padding-top: 130px; }
  .hero-content { grid-template-columns: 1fr; padding-top: 130px; }
  .hero-actions { justify-content: center; }
  .hero { min-height: 970px; }
  .hero-visual { height: 470px; margin-top: 10px; }
  .hero-earth-placeholder { left: 50%; width: min(440px, 80%); }
  .hero-orbit { left: 50%; width: 92%; }
  .intro-grid, .notice-grid { grid-template-columns: 1fr; gap: 35px; }
  .section-heading { grid-template-columns: 130px 1fr; gap: 28px; }
  .heading-link, .heading-note { grid-column: 2; }
  .research-list { grid-template-columns: 1fr; }
  .member-grid { grid-template-columns: repeat(2, 1fr); gap: 34px 18px; }
  .member-large .member-photo, .member-photo { min-height: 300px; }
  .footer-top { grid-template-columns: 1fr 1fr; }
  .footer-links { grid-column: 2; }
}

@media (max-width: 560px) {
  .container { width: calc(100% - 36px); }
  .nav-wrap { min-height: 75px; }
  .nav-contact { display: none; }
  .hero h1 { font-size: 52px; }
  .hero-text { font-size: 14px; }
  .hero-actions { align-items: center; flex-direction: column; gap: 20px; }
  .hero-visual { height: 360px; }
  .hero-earth-placeholder { top: 18px; right: 50%; width: 78%; }
  .hero-orbit { top: 43px; }
  .stat-top { top: 18px; right: 0; }
  .stat-bottom { bottom: 0; left: 50%; }
  .hero-footer > span { display: none; }
  .hero-footer { display: block; bottom: 28px; height: 20px; }
  .hero-dots { bottom: 0; }
  .intro, .directions, .research, .members, .notice { padding: 90px 0; }
  .intro-bottom { grid-template-columns: 1fr; gap: 26px; margin-top: 30px; }
  .intro-copy-column { grid-template-columns: 1fr; gap: 22px; }
  .intro-link { justify-self: start; margin-bottom: 0; }
  .section-heading { display: block; margin-bottom: 42px; }
  .section-heading .section-kicker { margin-bottom: 35px; }
  .heading-link, .heading-note { display: inline-flex; margin-top: 26px; }
  h2 { font-size: 44px; }
  .card-image { min-height: 260px; }
  .member-grid { grid-template-columns: 1fr 1fr; gap: 28px 12px; }
  .member-large .member-photo, .member-photo { min-height: 220px; }
  .direction-grid { grid-template-columns: 1fr; }
  .member-info { padding-top: 12px; }
  .member-info h3 { font-size: 13px; }
  .member-info p { font-size: 10px; }
  .notice-list a { grid-template-columns: 1fr 22px; gap: 5px; padding: 18px 0; font-size: 13px; }
  .notice-list time { grid-column: 1 / -1; }
  .media-strip { padding: 75px 0 85px; }
  .media-strip-label { align-items: flex-start; flex-direction: column; gap: 9px; }
  .media-grid { grid-template-columns: 1fr 1fr; }
  .media-wide { grid-column: 1 / -1; }
  .media-placeholder { min-height: 150px; }
  .contact { padding: 95px 0 105px; }
  .footer-top { grid-template-columns: 1fr; gap: 33px; padding-bottom: 50px; }
  .footer-links { grid-column: 1; justify-self: start; }
  .footer-bottom { align-items: flex-start; flex-direction: column; gap: 12px; }
  .utility-wrap span:last-child { display: none; }
  .brand-team { display: none; }
}

.contact-page { min-height: 100vh; background: var(--cream); }
.contact-header { position: relative; background: var(--deep); }
.contact-main { min-height: calc(100vh - 117px); padding: 130px 0; }
.contact-form-layout { display: grid; grid-template-columns: minmax(0, 0.9fr) minmax(360px, 0.8fr); gap: 120px; align-items: start; }
.contact-intro h1 { margin: 0 0 28px; color: var(--ink); font-size: clamp(48px, 6vw, 78px); letter-spacing: -0.075em; line-height: 1.05; }
.contact-intro h1 span { color: #6b8aa6; }
.contact-intro > p:not(.eyebrow) { max-width: 360px; margin: 0; color: var(--muted); font-size: 14px; line-height: 2; }
.contact-address { display: flex; flex-direction: column; gap: 6px; margin-top: 55px; padding-top: 17px; border-top: 1px solid var(--line); }
.contact-address span { color: var(--muted); font-family: var(--mono); font-size: 10px; letter-spacing: 0.1em; }
.contact-address strong { color: var(--accent-dark); font-family: var(--mono); font-size: 14px; font-weight: 400; }
.mail-form { display: flex; flex-direction: column; padding: 32px; border: 1px solid var(--line); background: var(--paper); }
.mail-form label { margin-bottom: 8px; color: var(--ink); font-size: 12px; font-weight: 700; }
.mail-form input, .mail-form textarea { width: 100%; margin-bottom: 23px; padding: 13px 14px; border: 1px solid var(--line); border-radius: 0; outline: 0; color: var(--ink); background: #fff; font: inherit; font-size: 13px; resize: vertical; }
.mail-form input:focus, .mail-form textarea:focus { border-color: var(--accent); box-shadow: 0 0 0 3px rgba(79, 159, 239, 0.12); }
.mail-form input::placeholder, .mail-form textarea::placeholder { color: #9aabb9; }
.mail-form .button { align-self: flex-start; border: 0; cursor: pointer; }
.form-note { margin: 14px 0 0; color: var(--muted); font-size: 10px; }

@media (max-width: 900px) {
  .contact-form-layout { grid-template-columns: 1fr; gap: 55px; }
}

@media (max-width: 560px) {
  .contact-main { padding: 85px 0; }
  .mail-form { padding: 22px; }
}
.mail-provider-modal { position: fixed; z-index: 20; inset: 0; display: grid; padding: 24px; background: rgba(13, 46, 74, 0.56); place-items: center; }
.mail-provider-modal[hidden] { display: none; }
.mail-provider-panel { position: relative; width: min(100%, 540px); padding: 42px; border: 1px solid rgba(79, 159, 239, 0.42); background: var(--paper); box-shadow: 0 24px 70px rgba(13, 46, 74, 0.2); }
.modal-close { position: absolute; top: 16px; right: 18px; width: 28px; height: 28px; border: 0; color: var(--muted); background: transparent; cursor: pointer; font-size: 25px; line-height: 1; }
.modal-close:hover { color: var(--ink); }
.mail-provider-panel h2 { margin-bottom: 13px; color: var(--ink); font-size: 36px; }
.modal-description { margin: 0 0 28px; color: var(--muted); font-size: 13px; }
.mail-provider-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
.mail-provider { display: flex; min-height: 112px; flex-direction: column; justify-content: space-between; padding: 17px; border: 1px solid var(--line); color: var(--ink); background: #fff; font-size: 13px; font-weight: 700; transition: transform 0.2s ease, border-color 0.2s ease; }
.mail-provider:hover { border-color: var(--accent); transform: translateY(-3px); }
.mail-provider > span { align-self: flex-end; color: var(--accent-dark); font-size: 18px; font-weight: 400; }
.mail-provider small { color: var(--muted); font-size: 10px; font-weight: 400; }
.qq-provider { border-top: 3px solid #1688e8; }
.netease-provider { border-top: 3px solid #df4f46; }
.gmail-provider { border-top: 3px solid #4285f4; }

@media (max-width: 560px) {
  .mail-provider-panel { padding: 35px 22px 22px; }
  .mail-provider-grid { grid-template-columns: 1fr; }
  .mail-provider { min-height: 78px; }
}