:root {
  --navy: #071f3e;
  --navy-2: #0b3154;
  --blue: #1491ce;
  --blue-light: #7ccde8;
  --ink: #0b2240;
  --muted: #66798c;
  --line: #d7e3ea;
  --soft: #f2f8fb;
  --white: #fff;
  --max-width: 1180px;
  --header-height: 86px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--white);
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}
img { display: block; width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
.container { width: 100%; max-width: var(--max-width); margin: 0 auto; padding-left: 24px; padding-right: 24px; }
.section { padding: 112px 0; }

h1, h2, h3 {
  font-family: "Songti SC", "STSong", "SimSun", serif;
  font-weight: 500;
  letter-spacing: .02em;
}

.header {
  position: fixed;
  inset: 0 0 auto;
  height: var(--header-height);
  background: rgba(255,255,255,.96);
  border-bottom: 1px solid rgba(215,227,234,.85);
  z-index: 1000;
  transition: box-shadow .25s ease;
}
.header.scrolled { box-shadow: 0 10px 28px rgba(7,31,62,.08); }
.header-inner { height: 100%; display: flex; align-items: center; justify-content: space-between; }
.logo { display: flex; align-items: center; }
.logo-img { width: auto; height: 44px; max-width: 220px; object-fit: contain; }
.nav { display: flex; gap: 44px; align-items: center; }
.nav-link { position: relative; padding: 28px 0 25px; font-size: 15px; color: #2f4052; }
.nav-link::after { content: ""; position: absolute; left: 0; right: 100%; bottom: 0; height: 2px; background: var(--blue); transition: right .25s ease; }
.nav-link:hover, .nav-link.active { color: var(--blue); }
.nav-link:hover::after, .nav-link.active::after { right: 0; }
.mobile-menu-btn { display: none; border: 0; background: transparent; padding: 8px; }
.mobile-menu-btn span { display: block; width: 24px; height: 2px; margin: 5px 0; background: var(--navy); }

.hero {
  position: relative;
  isolation: isolate;
  overflow: hidden;
  min-height: 740px;
  padding-top: var(--header-height);
  display: flex;
  align-items: center;
  color: var(--white);
  background:
    radial-gradient(ellipse at 76% 92%, rgba(24, 83, 190, .42) 0%, rgba(10, 51, 112, .22) 34%, transparent 58%),
    linear-gradient(105deg, #04172f 0%, #051a36 43%, #082653 76%, #092e62 100%);
}
.hero-visual {
  position: absolute;
  top: var(--header-height);
  left: 75%;
  height: calc(100% - var(--header-height));
  aspect-ratio: 1920 / 959;
  transform: translateX(-78%);
  z-index: 0;
  pointer-events: none;
  background: url("../images/mascot.jpg") center / 100% 100% no-repeat;
  -webkit-mask-image: linear-gradient(90deg, transparent 0%, #000 10%, #000 92%, transparent 100%);
  mask-image: linear-gradient(90deg, transparent 0%, #000 10%, #000 92%, transparent 100%);
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  pointer-events: none;
  background:
    radial-gradient(circle at 78% 43%, rgba(127, 224, 255, .22) 0, rgba(49, 168, 226, .1) 19%, transparent 39%),
    radial-gradient(circle at 88% 59%, rgba(42, 139, 255, .13) 0, transparent 30%);
  mix-blend-mode: screen;
  animation: hero-glow 5.6s ease-in-out infinite alternate;
}
.hero-particles {
  position: absolute;
  top: 13%;
  right: 2%;
  z-index: 2;
  width: min(46vw, 660px);
  height: 68%;
  pointer-events: none;
}
.hero-particles span {
  position: absolute;
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: rgba(218, 250, 255, .95);
  box-shadow: 0 0 7px rgba(103, 220, 255, .95), 0 0 16px rgba(60, 168, 255, .55);
  opacity: .18;
  animation: hero-particle-twinkle 3.8s ease-in-out infinite;
}
.hero-particles span:nth-child(1) { left: 10%; top: 30%; width: 6px; height: 6px; animation-delay: -.4s; }
.hero-particles span:nth-child(2) { left: 30%; top: 9%; animation-delay: -2.1s; animation-duration: 4.5s; }
.hero-particles span:nth-child(3) { left: 52%; top: 23%; width: 7px; height: 7px; animation-delay: -1.2s; }
.hero-particles span:nth-child(4) { left: 78%; top: 12%; width: 4px; height: 4px; animation-delay: -3s; animation-duration: 4.8s; }
.hero-particles span:nth-child(5) { left: 91%; top: 46%; width: 6px; height: 6px; animation-delay: -1.8s; }
.hero-particles span:nth-child(6) { left: 71%; top: 70%; animation-delay: -.9s; animation-duration: 4.4s; }
.hero-particles span:nth-child(7) { left: 41%; top: 82%; width: 6px; height: 6px; animation-delay: -2.7s; }
.hero-particles span:nth-child(8) { left: 17%; top: 67%; width: 4px; height: 4px; animation-delay: -1.5s; animation-duration: 4.7s; }
.hero-inner { position: relative; z-index: 3; }
@keyframes hero-glow {
  from { opacity: .52; transform: scale(.99); }
  to { opacity: .82; transform: scale(1.018); }
}
@keyframes hero-particle-twinkle {
  0%, 100% { opacity: .16; transform: translate3d(0, 10px, 0) scale(.68); }
  45% { opacity: .95; transform: translate3d(-7px, -7px, 0) scale(1.28); }
  70% { opacity: .44; transform: translate3d(4px, -14px, 0) scale(.9); }
}
.hero-content { max-width: 680px; padding: 80px 0 60px; }
.hero-slogan, .page-kicker, .section-label { display: block; color: var(--blue); font-size: 13px; font-weight: 700; letter-spacing: .18em; line-height: 1.4; }
.hero-slogan { color: var(--blue-light); margin-bottom: 28px; }
.hero-title { font-size: clamp(46px, 5.2vw, 76px); line-height: 1.13; margin-bottom: 30px; }
.hero-desc { max-width: 620px; color: rgba(255,255,255,.8); font-size: 18px; line-height: 1.9; margin-bottom: 38px; }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.btn { min-width: 138px; display: inline-flex; justify-content: center; align-items: center; padding: 13px 26px; border: 1px solid transparent; font-size: 15px; transition: background .2s ease, color .2s ease, border-color .2s ease; }
.btn-primary { background: var(--blue); color: var(--white); }
.btn-primary:hover { background: #087eb8; }
.btn-outline { border-color: rgba(255,255,255,.62); color: var(--white); }
.btn-outline:hover { background: var(--white); color: var(--navy); }
.hero-actions .btn-outline { background: var(--white); border-color: var(--white); color: var(--navy); }
.hero-actions .btn-outline:hover { background: #e8f4fa; border-color: #e8f4fa; color: var(--navy); }

.intro-section { background: var(--white); }
.intro-grid, .about-overview-grid { display: grid; grid-template-columns: 1.02fr .98fr; gap: clamp(54px, 7vw, 104px); align-items: center; }
.intro-image, .about-overview-image { position: relative; }
.intro-image::before, .about-overview-image::before { content: ""; position: absolute; left: -20px; top: 20px; width: 100%; height: 100%; background: var(--soft); z-index: -1; }
.intro-image img, .about-overview-image img { aspect-ratio: 16 / 9; height: auto; background: var(--soft); }
.intro-image img { object-fit: contain; }
.about-overview-image img { object-fit: cover; object-position: center; }
.intro-content h2, .about-overview-content h2, .contact-intro h2 { font-size: clamp(36px, 4vw, 54px); line-height: 1.32; margin: 20px 0 28px; }
.intro-content p, .about-overview-content p, .contact-intro p { color: var(--muted); font-size: 17px; margin-bottom: 22px; }
.text-link { display: inline-flex; gap: 22px; align-items: center; margin-top: 16px; color: var(--blue); font-weight: 600; }
.text-link span { font-size: 24px; transition: transform .2s ease; }
.text-link:hover span { transform: translateX(5px); }

.business-section { background: var(--soft); }
.section-heading { max-width: 760px; margin: 0 auto 72px; text-align: center; }
.section-heading.align-left { margin-left: 0; text-align: left; }
.section-heading h2 { font-size: clamp(38px, 4.5vw, 58px); line-height: 1.28; margin: 18px 0; }
.section-heading p { color: var(--muted); font-size: 17px; }
.business-feature { display: grid; grid-template-columns: .86fr 1.14fr; min-height: 430px; margin-bottom: 38px; background: var(--white); }
.business-feature.reverse { grid-template-columns: 1.14fr .86fr; }
.business-feature.reverse .business-copy { order: 2; }
.business-feature.reverse .business-image { order: 1; }
.business-copy { display: flex; flex-direction: column; justify-content: center; padding: 64px; }
.feature-index { color: var(--blue); font-size: 13px; font-weight: 700; letter-spacing: .15em; }
.business-copy h3 { font-size: clamp(30px, 2.8vw, 40px); line-height: 1.28; margin: 18px 0 22px; white-space: nowrap; }
.business-copy p { color: var(--muted); font-size: 16px; }
.business-image img { height: 100%; min-height: 430px; object-fit: cover; }

.strengths-section { background: var(--white); }
.strengths-grid { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.strength-item { position: relative; isolation: isolate; overflow: hidden; padding: 42px 34px 48px; border-right: 1px solid var(--line); transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease; }
.strength-item::before, .culture-item::before { content: ""; position: absolute; inset: 0; z-index: -1; background: linear-gradient(135deg, var(--navy-2), #0b6e9d); opacity: 0; transition: opacity .28s ease; }
.strength-item:last-child { border-right: 0; }
.strength-item > span { color: var(--blue); font-size: 13px; letter-spacing: .12em; transition: color .28s ease; }
.strength-item h3 { font-size: 28px; margin: 28px 0 14px; transition: color .28s ease; }
.strength-item p { color: var(--muted); font-size: 15px; transition: color .28s ease; }

.cta-section, .statement-section { color: var(--white); background: var(--navy); }
.cta-inner { min-height: 270px; display: flex; align-items: center; justify-content: space-between; gap: 60px; }
.cta-inner h2 { font-size: clamp(34px, 4.2vw, 54px); line-height: 1.3; margin-top: 16px; }
.section-label.light { color: var(--blue-light); }

.page-hero { min-height: 480px; padding-top: var(--header-height); display: flex; align-items: center; color: var(--white); background: linear-gradient(90deg, rgba(5,25,48,.93), rgba(5,25,48,.5)), url("../images/command-center.jpg") center / cover no-repeat; }
.page-hero-about { background-image: linear-gradient(90deg, rgba(5,25,48,.9), rgba(5,25,48,.16)), url("../images/about-hero-v2.png"); background-position: center; }
.page-hero-business { background-image: linear-gradient(90deg, rgba(5,25,48,.88), rgba(5,25,48,.2)), url("../images/business-hero-v2.png"); background-position: center; }
.page-hero-contact { background-image: linear-gradient(90deg, rgba(5,25,48,.9), rgba(5,25,48,.16)), url("../images/contact-hero-v2.png"); background-position: center; }
.page-kicker { color: var(--blue-light); margin-bottom: 18px; }
.page-hero h1 { font-size: clamp(48px, 6vw, 74px); line-height: 1.1; }
.page-hero p { margin-top: 20px; color: rgba(255,255,255,.76); font-size: 18px; }

.about-overview { background: var(--white); }
.about-overview-content p + p { margin-top: 6px; }
.statement-inner { min-height: 360px; display: flex; flex-direction: column; justify-content: center; }
.statement-inner p { max-width: 1000px; margin-top: 22px; font-family: "Songti SC", "STSong", serif; font-size: clamp(32px, 4vw, 52px); line-height: 1.55; }

.culture-section { background: var(--soft); }
.culture-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.culture-item { position: relative; isolation: isolate; overflow: hidden; padding: 50px 46px; border-right: 1px solid var(--line); transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease; }
.culture-item:last-child { border-right: 0; }
.culture-item h3 { color: var(--blue); font-size: 22px; margin-bottom: 20px; transition: color .28s ease; }
.culture-item p { color: var(--muted); transition: color .28s ease; }
.cooperation-section { margin-top: 94px; }
.cooperation-section h3 { font-size: 38px; margin: 16px 0 28px; }
.cooperation-list { display: grid; grid-template-columns: repeat(4, 1fr); border-top: 1px solid var(--line); }
.cooperation-list span { padding: 20px 8px; border-bottom: 1px solid var(--line); color: #34495d; }

.business-detail { scroll-margin-top: var(--header-height); }
.education-detail { background: var(--soft); }
.detail-intro { display: grid; grid-template-columns: 1.05fr .95fr; gap: 80px; align-items: end; margin-bottom: 52px; }
.detail-intro h2 { font-size: clamp(38px, 4vw, 50px); line-height: 1.25; margin-top: 18px; white-space: nowrap; }
.detail-intro > p { color: var(--muted); font-size: 17px; padding-bottom: 8px; }
.detail-photo { height: 520px; overflow: hidden; margin-bottom: 74px; }
.detail-photo img { height: 100%; object-fit: cover; }
.services-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--line); }
.service-item { position: relative; isolation: isolate; overflow: hidden; min-height: 250px; padding: 38px 34px; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line); cursor: default; transition: transform .28s ease, box-shadow .28s ease, border-color .28s ease; }
.service-item::before { content: ""; position: absolute; inset: 0; z-index: -1; background: linear-gradient(135deg, var(--navy-2), #0b6e9d); opacity: 0; transition: opacity .28s ease; }
.service-item:nth-child(3n) { border-right: 0; }
.service-item > span { color: var(--blue); font-size: 13px; letter-spacing: .12em; transition: color .28s ease; }
.service-item h3 { font-size: 24px; margin: 24px 0 12px; transition: color .28s ease; }
.service-item p { color: var(--muted); font-size: 15px; transition: color .28s ease; }
@media (hover: hover) and (pointer: fine) {
  .service-item:hover { z-index: 2; transform: translateY(-6px); border-color: transparent; box-shadow: 0 20px 42px rgba(7,31,62,.2); }
  .service-item:hover::before { opacity: 1; }
  .service-item:hover > span { color: var(--blue-light); }
  .service-item:hover h3 { color: var(--white); }
  .service-item:hover p { color: rgba(255,255,255,.74); }
  .strength-item:hover, .culture-item:hover { z-index: 2; transform: translateY(-6px); border-color: transparent; box-shadow: 0 20px 42px rgba(7,31,62,.2); }
  .strength-item:hover::before, .culture-item:hover::before { opacity: 1; }
  .strength-item:hover > span { color: var(--blue-light); }
  .strength-item:hover h3, .culture-item:hover h3 { color: var(--white); }
  .strength-item:hover p, .culture-item:hover p { color: rgba(255,255,255,.74); }
}

.contact-section { min-height: 560px; display: flex; align-items: center; }
.contact-layout { display: grid; grid-template-columns: 1fr 1fr; gap: 100px; align-items: center; }
.contact-details { border-top: 1px solid var(--line); }
.contact-row { display: grid; grid-template-columns: 120px 1fr; gap: 24px; padding: 28px 0; border-bottom: 1px solid var(--line); }
.contact-row span { color: var(--muted); font-size: 14px; }
.contact-row a { color: var(--navy); font-size: 18px; overflow-wrap: anywhere; }
.contact-row a:hover { color: var(--blue); }
.contact-row p { color: var(--navy); font-size: 17px; line-height: 1.75; }

.footer { background: #06192f; color: var(--white); padding-top: 70px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr .7fr 1fr; gap: 80px; padding-bottom: 55px; }
.footer-logo { width: 178px; height: auto; object-fit: contain; object-position: left center; margin-bottom: 18px; }
.footer-brand p, .footer-contact p, .footer-links a { color: rgba(255,255,255,.58); font-size: 14px; }
.footer-links, .footer-contact { display: flex; flex-direction: column; gap: 9px; }
.footer h4 { color: var(--white); font-size: 14px; margin-bottom: 9px; }
.footer a:hover { color: var(--blue-light); }
.footer-bottom { display: flex; justify-content: space-between; align-items: center; gap: 18px 32px; flex-wrap: wrap; padding: 22px 24px 28px; border-top: 1px solid rgba(255,255,255,.1); color: rgba(255,255,255,.52); font-size: 12px; }
.footer-bottom a { color: inherit; }
.footer-bottom a:hover { color: var(--blue-light); }

@media (max-width: 980px) {
  .section { padding: 86px 0; }
  .nav { gap: 26px; }
  .intro-grid, .about-overview-grid, .detail-intro, .contact-layout { grid-template-columns: 1fr; gap: 46px; }
  .intro-image img, .about-overview-image img { height: auto; }
  .business-feature, .business-feature.reverse { grid-template-columns: 1fr; }
  .business-feature.reverse .business-copy { order: 1; }
  .business-feature.reverse .business-image { order: 2; }
  .business-image img { min-height: 360px; }
  .strengths-grid { grid-template-columns: repeat(2, 1fr); }
  .strength-item:nth-child(2) { border-right: 0; }
  .strength-item:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .services-grid { grid-template-columns: repeat(2, 1fr); }
  .service-item:nth-child(3n) { border-right: 1px solid var(--line); }
  .service-item:nth-child(2n) { border-right: 0; }
  .culture-grid { grid-template-columns: 1fr; }
  .culture-item { border-right: 0; border-bottom: 1px solid var(--line); }
  .culture-item:last-child { border-bottom: 0; }
  .cooperation-list { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 720px) {
  :root { --header-height: 68px; }
  .container { padding-left: 18px; padding-right: 18px; }
  .logo-img { width: auto; height: 38px; max-width: 165px; }
  .mobile-menu-btn { display: block; }
  .nav { position: absolute; top: var(--header-height); left: 0; right: 0; display: none; flex-direction: column; gap: 0; align-items: stretch; padding: 8px 18px 18px; background: var(--white); border-bottom: 1px solid var(--line); box-shadow: 0 14px 24px rgba(7,31,62,.08); }
  .nav.open { display: flex; }
  .nav-link { padding: 14px 6px; }
  .nav-link::after { display: none; }
  .hero { min-height: 650px; background-position: 76% center; }
  .hero-visual {
    top: calc(var(--header-height) + 18px);
    left: 84%;
    height: 78%;
    filter: brightness(.76) saturate(.9);
    opacity: .9;
  }
  .hero::after {
    content: "";
    position: absolute;
    inset: var(--header-height) 0 0;
    z-index: 1;
    pointer-events: none;
    background:
      linear-gradient(90deg, rgba(3, 17, 38, .9) 0%, rgba(3, 17, 38, .78) 58%, rgba(3, 17, 38, .46) 100%),
      linear-gradient(180deg, rgba(4, 22, 48, .08) 0%, rgba(4, 22, 48, .38) 100%);
  }
  .hero-particles { top: 17%; right: -18%; width: 92vw; height: 60%; }
  .hero-content { padding: 80px 0 55px; }
  .hero-title { font-size: clamp(40px, 11.5vw, 48px); text-shadow: 0 2px 18px rgba(0, 10, 28, .4); }
  .hero-desc { max-width: 96%; font-size: 16px; color: rgba(255,255,255,.88); text-shadow: 0 1px 12px rgba(0, 10, 28, .42); }
  .section { padding: 72px 0; }
  .intro-image img, .about-overview-image img { height: auto; }
  .intro-content h2, .about-overview-content h2, .contact-intro h2 { font-size: 36px; }
  .section-heading { margin-bottom: 48px; }
  .section-heading h2 { font-size: 38px; }
  .business-copy { padding: 42px 28px; }
  .business-image img { min-height: 280px; }
  .strengths-grid, .services-grid { grid-template-columns: 1fr; }
  .strength-item, .service-item, .service-item:nth-child(3n), .service-item:nth-child(2n) { border-right: 0; border-bottom: 1px solid var(--line); }
  .strength-item:last-child, .service-item:last-child { border-bottom: 0; }
  .cta-inner { min-height: 320px; flex-direction: column; align-items: flex-start; justify-content: center; gap: 32px; }
  .cta-inner h2 { font-size: 36px; }
  .page-hero { min-height: 390px; }
  .page-hero h1 { font-size: 50px; }
  .detail-photo { height: 310px; margin-bottom: 48px; }
  .detail-intro { gap: 24px; }
  .business-copy h3 { font-size: clamp(26px, 7.3vw, 32px); }
  .detail-intro h2 { font-size: clamp(26px, 7.3vw, 32px); }
  .cooperation-list { grid-template-columns: 1fr; }
  .contact-section { min-height: 640px; }
  .contact-row { grid-template-columns: 1fr; gap: 6px; }
  .footer-grid { grid-template-columns: 1fr; gap: 38px; }
  .footer-logo { width: 162px; height: auto; }
  .footer-bottom { flex-direction: column; align-items: flex-start; gap: 5px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}