*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0}
h1,h2,h3,h4,p,figure{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg{display:block;max-width:100%}
button{font:inherit;color:inherit}
a{color:inherit}

:root{
  --deep:#071A2F;
  --deep-2:#0E2A47;
  --glass:rgba(24,58,92,.55);
  --cyan:#35F0D0;
  --cyan-soft:#9DF7E7;
  --orange:#FF8A3D;
  --terra:#C9714A;
  --violet:#6E6A8A;
  --stone:#8A93A0;
  --moss:#3F6B57;
  --cream:#F2EDE4;
  --text:#B7C4D2;
  --text-strong:#CBD6E3;
  --line:rgba(138,147,160,.24);
  --line-strong:rgba(138,147,160,.42);
  --shell:min(100% - 32px, 1240px);
  --sans:"PingFang SC","Noto Sans SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --ease:cubic-bezier(.22,.61,.36,1);
}

body{
  background-color:var(--deep);
  background-image:
    linear-gradient(to right, rgba(138,147,160,.055) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(138,147,160,.055) 1px, transparent 1px);
  background-size:64px 64px;
  color:var(--text);
  font-family:var(--sans);
  font-size:16px;
  line-height:1.75;
  letter-spacing:.01em;
  -webkit-font-smoothing:antialiased;
}

::selection{background:var(--cyan);color:#04121f}

h1,h2,h3,h4{
  color:var(--cream);
  font-weight:900;
  line-height:1.14;
  letter-spacing:-.02em;
  text-wrap:balance;
}
h1{font-size:clamp(2rem,4.6vw,3.4rem)}
h2{font-size:clamp(1.5rem,3vw,2.25rem)}
h3{font-size:clamp(1.15rem,1.8vw,1.4rem)}
p{text-wrap:pretty}

:focus-visible{outline:2px solid var(--cyan);outline-offset:3px;border-radius:3px}

#main-content{scroll-margin-top:110px}

/* ---------- skip link ---------- */
.skip-link{
  position:fixed;
  top:8px;
  left:8px;
  z-index:300;
  padding:10px 18px;
  border-radius:6px;
  background:var(--cyan);
  color:#04121f;
  font-weight:700;
  font-size:14px;
  text-decoration:none;
  transform:translateY(-180%);
  transition:transform .22s var(--ease);
}
.skip-link:focus{transform:translateY(0)}

/* ---------- header ---------- */
.site-header{
  position:sticky;
  top:0;
  z-index:120;
  background:var(--glass);
  -webkit-backdrop-filter:blur(14px) saturate(1.15);
  backdrop-filter:blur(14px) saturate(1.15);
  border-bottom:1px solid var(--line);
  color:var(--cream);
  transition:background .3s var(--ease),border-color .3s var(--ease),box-shadow .3s var(--ease);
}
.site-header.is-condensed{
  background:var(--deep);
  -webkit-backdrop-filter:none;
  backdrop-filter:none;
  border-bottom-color:rgba(53,240,208,.26);
  box-shadow:0 14px 34px rgba(3,12,22,.55);
}

.header-grid{
  width:var(--shell);
  margin-inline:auto;
  display:grid;
  grid-template-columns:auto minmax(0,1fr) auto;
  align-items:end;
  gap:10px 24px;
  padding-block:14px 12px;
}

.brand{
  display:inline-flex;
  flex-direction:column;
  gap:3px;
  text-decoration:none;
  min-width:0;
}
.brand__mark{
  display:inline-flex;
  align-items:center;
  font-size:22px;
  font-weight:900;
  letter-spacing:.01em;
  line-height:1.05;
  color:var(--cream);
}
.brand__mark::before{
  content:"";
  width:8px;
  height:8px;
  margin-right:9px;
  background:var(--cyan);
  transform:translateY(-2px);
}
.brand__sub{
  font-size:11px;
  letter-spacing:.16em;
  color:var(--stone);
  line-height:1.4;
}

.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:9px 14px;
  border-radius:999px;
  border:1px solid rgba(53,240,208,.42);
  background:rgba(53,240,208,.08);
  color:var(--cyan);
  font-weight:700;
  font-size:13px;
  letter-spacing:.08em;
  cursor:pointer;
  transition:background .2s var(--ease),border-color .2s var(--ease);
}
.nav-toggle:hover{background:rgba(53,240,208,.16)}
.nav-toggle__bars{position:relative;display:block;width:16px;height:10px}
.nav-toggle__bars::before,
.nav-toggle__bars::after{
  content:"";
  position:absolute;
  left:0;
  width:16px;
  height:2px;
  background:currentColor;
  transition:transform .22s var(--ease),top .22s var(--ease);
}
.nav-toggle__bars::before{top:0}
.nav-toggle__bars::after{top:8px}
.site-header[data-open] .nav-toggle__bars::before{top:4px;transform:rotate(45deg)}
.site-header[data-open] .nav-toggle__bars::after{top:4px;transform:rotate(-45deg)}
.nav-toggle__label{line-height:1}

.primary-nav{display:flex;justify-content:flex-end;min-width:0}

.nav-steps{display:flex;align-items:flex-end;gap:2px;flex-wrap:wrap}
.nav-steps__item{position:relative;transform:translateY(var(--step,0))}
.nav-steps__item:nth-child(1){--step:-8px}
.nav-steps__item:nth-child(2){--step:-3px}
.nav-steps__item:nth-child(3){--step:-13px}
.nav-steps__item:nth-child(4){--step:0px}
.nav-steps__item:nth-child(5){--step:4px}
.nav-steps__item:nth-child(6){--step:8px}

.nav-steps__link{
  display:block;
  padding:7px 12px 6px;
  border-radius:6px 6px 0 0;
  font-size:18px;
  font-weight:700;
  letter-spacing:.02em;
  line-height:1.25;
  color:var(--text-strong);
  text-decoration:none;
  transition:color .2s var(--ease),background .2s var(--ease),box-shadow .2s var(--ease);
}
.nav-steps__link:hover{color:var(--cyan);background:rgba(53,240,208,.08)}
.nav-steps__link[aria-current="page"]{
  color:var(--cyan);
  background:rgba(53,240,208,.1);
  box-shadow:inset 0 -2px 0 var(--cyan);
}

.nav-steps__item--accent .nav-steps__link{
  background:var(--orange);
  color:#06182b;
  box-shadow:0 10px 22px rgba(255,138,61,.26);
}
.nav-steps__item--accent .nav-steps__link:hover{
  background:#FF9E5C;
  color:#06182b;
}
.nav-steps__item--accent .nav-steps__link[aria-current="page"]{
  background:var(--orange);
  color:#06182b;
  box-shadow:inset 0 -3px 0 #06182b;
}
.nav-steps__badge{
  display:inline-block;
  margin-left:8px;
  padding:1px 5px;
  border-radius:3px;
  background:#06182b;
  color:var(--orange);
  font-size:10px;
  font-weight:700;
  letter-spacing:.08em;
  vertical-align:2px;
}

.header-cta{
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:10px 18px;
  border-radius:999px;
  border:1px solid rgba(53,240,208,.45);
  background:rgba(53,240,208,.07);
  color:var(--cyan);
  font-size:15px;
  font-weight:700;
  letter-spacing:.04em;
  text-decoration:none;
  white-space:nowrap;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.header-cta::after{content:"→";font-size:14px;line-height:1}
.header-cta:hover{background:var(--cyan);color:#04121f;border-color:var(--cyan)}

.header-progress{height:2px;background:rgba(138,147,160,.18);overflow:hidden}
.header-progress__bar{
  display:block;
  height:100%;
  width:100%;
  background:linear-gradient(90deg,var(--cyan),var(--orange));
  transform:scaleX(0);
  transform-origin:left center;
}

/* ---------- footer ---------- */
.site-footer{
  margin-top:clamp(56px,8vw,104px);
  background:linear-gradient(180deg,rgba(14,42,71,.92) 0%,var(--deep) 58%);
  border-top:1px solid var(--line);
  color:var(--text);
}
.footer-grid{
  width:var(--shell);
  margin-inline:auto;
  display:grid;
  grid-template-columns:minmax(0,1.35fr) minmax(0,.85fr) minmax(0,.85fr) minmax(0,1.2fr);
  gap:36px 40px;
  padding-block:64px 44px;
}
.footer-brand__mark{
  font-size:clamp(26px,3vw,34px);
  font-weight:900;
  letter-spacing:-.02em;
  color:var(--cream);
  line-height:1.1;
}
.footer-brand__line{
  margin-top:12px;
  font-size:15px;
  letter-spacing:.16em;
  color:var(--cyan-soft);
}
.footer-brand__note{
  margin-top:14px;
  max-width:32ch;
  font-size:13px;
  line-height:1.85;
  color:var(--stone);
}
.footer-block{min-width:0}
.footer-heading{
  display:flex;
  align-items:center;
  gap:9px;
  margin-bottom:16px;
  font-size:11px;
  font-weight:700;
  letter-spacing:.2em;
  color:var(--stone);
  line-height:1.4;
}
.footer-heading::before{content:"";width:14px;height:1px;background:var(--cyan)}
.footer-list{display:grid;gap:9px;font-size:14px}
.footer-list a{
  display:inline-block;
  padding:2px 0;
  color:var(--text-strong);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .2s var(--ease),border-color .2s var(--ease);
}
.footer-list a:hover{color:var(--cyan);border-bottom-color:rgba(53,240,208,.5)}
.footer-contact__row{
  display:flex;
  flex-wrap:wrap;
  gap:2px 12px;
  padding:8px 0;
  border-bottom:1px dashed rgba(138,147,160,.22);
  font-size:14px;
}
.footer-contact__label{
  flex:0 0 40px;
  padding-top:2px;
  font-size:11px;
  letter-spacing:.18em;
  color:var(--stone);
}
.footer-contact__value{color:var(--text-strong);word-break:break-word}
.footer-note{
  margin-top:16px;
  font-size:12px;
  line-height:1.85;
  color:var(--stone);
}
.footer-base{
  width:var(--shell);
  margin-inline:auto;
  display:flex;
  flex-wrap:wrap;
  justify-content:space-between;
  gap:8px 24px;
  padding-block:18px 30px;
  border-top:1px solid var(--line);
  font-size:12px;
  letter-spacing:.08em;
  color:var(--stone);
}
.footer-base__text{font-variant-numeric:tabular-nums}

/* ---------- layout utilities ---------- */
.page-shell{width:var(--shell);margin-inline:auto}
.section{padding-block:clamp(48px,7vw,96px)}
.grid-12{
  display:grid;
  grid-template-columns:repeat(12,minmax(0,1fr));
  gap:clamp(18px,2.4vw,28px);
}
.col-4{grid-column:span 4}
.col-5{grid-column:span 5}
.col-7{grid-column:span 7}
.col-8{grid-column:span 8}
.col-12{grid-column:span 12}

.tech-grid{
  background-image:
    linear-gradient(to right, rgba(138,147,160,.12) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(138,147,160,.12) 1px, transparent 1px);
  background-size:48px 48px;
}

.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin-bottom:14px;
  font-size:12px;
  font-weight:700;
  letter-spacing:.18em;
  color:var(--cyan);
  line-height:1.4;
}
.eyebrow::before{content:"";width:18px;height:1px;background:currentColor}

.lead{
  max-width:62ch;
  font-size:clamp(16px,1.5vw,19px);
  line-height:1.8;
  color:var(--text-strong);
}

.rule{border:0;border-top:1px solid var(--line);margin-block:clamp(24px,3vw,40px)}

.prose{max-width:70ch;font-size:16px}
.prose > * + *{margin-top:1.1em}
.prose h2{margin-top:2em;font-size:clamp(22px,2.4vw,28px)}
.prose h3{margin-top:1.6em;font-size:19px;letter-spacing:0}
.prose strong{color:var(--cream)}
.prose a{color:var(--cyan-soft);text-decoration:underline;text-underline-offset:3px}
.prose ul{display:grid;gap:9px;margin-top:1em}
.prose ul li{position:relative;padding-left:22px}
.prose ul li::before{
  content:"";
  position:absolute;
  left:2px;
  top:.72em;
  width:7px;
  height:7px;
  background:var(--cyan);
  border-radius:1px;
  transform:rotate(45deg);
}

/* ---------- buttons & tags ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:10px;
  padding:12px 22px;
  border-radius:999px;
  border:1px solid var(--line-strong);
  background:transparent;
  color:var(--cream);
  font-size:15px;
  font-weight:700;
  letter-spacing:.04em;
  line-height:1.3;
  text-decoration:none;
  cursor:pointer;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease),box-shadow .2s var(--ease);
}
.btn:hover{border-color:var(--cyan);color:var(--cyan)}
.btn--accent{
  background:var(--orange);
  border-color:var(--orange);
  color:#0a1a2a;
  box-shadow:0 12px 26px rgba(255,138,61,.24);
}
.btn--accent:hover{background:#FF9E5C;border-color:#FF9E5C;color:#0a1a2a}
.btn--ghost{border-color:rgba(53,240,208,.42);color:var(--cyan)}
.btn--ghost:hover{background:rgba(53,240,208,.1);border-color:var(--cyan);color:var(--cyan)}

.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 9px;
  border-radius:4px;
  border:1px solid rgba(110,106,138,.5);
  background:rgba(110,106,138,.28);
  color:#D8D4E9;
  font-size:12px;
  font-weight:700;
  letter-spacing:.06em;
  line-height:1.5;
}
.tag--orange{background:rgba(201,113,74,.24);border-color:rgba(201,113,74,.55);color:#F3B08E}
.tag--moss{background:rgba(63,107,87,.3);border-color:rgba(63,107,87,.62);color:#9FD7BC}

/* ---------- breadcrumb ---------- */
.breadcrumb{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  padding-block:20px 0;
  font-size:12px;
  letter-spacing:.12em;
  color:var(--stone);
}
.breadcrumb a{color:var(--stone);text-decoration:none;transition:color .2s var(--ease)}
.breadcrumb a:hover{color:var(--cyan)}
.breadcrumb__sep{color:rgba(138,147,160,.6)}
.breadcrumb [aria-current="page"]{color:var(--cyan-soft)}

/* ---------- media frame ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  border:1px solid var(--line-strong);
  border-radius:14px;
  background:linear-gradient(160deg,rgba(24,58,92,.8),rgba(14,42,71,.96));
  box-shadow:0 24px 60px rgba(3,12,22,.45);
}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background-image:
    linear-gradient(to right, rgba(138,147,160,.14) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(138,147,160,.14) 1px, transparent 1px);
  background-size:40px 40px;
}
.media-frame__img{
  display:block;
  width:100%;
  height:auto;
  aspect-ratio:16 / 10;
  object-fit:cover;
}
.media-frame__caption{
  position:relative;
  z-index:1;
  padding:12px 16px;
  border-top:1px solid var(--line);
  background:rgba(7,26,47,.62);
  font-size:12px;
  letter-spacing:.1em;
  line-height:1.7;
  color:var(--stone);
}

/* ---------- tabs ---------- */
.tabs{display:block}
.tabs__list{
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  border-bottom:1px solid var(--line);
}
.tabs__tab{
  appearance:none;
  padding:10px 16px;
  border:1px solid transparent;
  border-bottom:none;
  border-radius:8px 8px 0 0;
  background:transparent;
  color:var(--text);
  font-size:15px;
  font-weight:700;
  letter-spacing:.04em;
  line-height:1.3;
  cursor:pointer;
  transition:background .2s var(--ease),color .2s var(--ease),border-color .2s var(--ease);
}
.tabs__tab:hover{color:var(--cyan-soft);background:rgba(53,240,208,.07)}
.tabs__tab[aria-selected="true"]{
  background:var(--deep-2);
  color:var(--cyan);
  border-color:rgba(53,240,208,.35);
  box-shadow:inset 0 2px 0 var(--cyan);
}
.tabs__panel{padding-block:18px 0}
.tabs__panel[hidden]{display:none}

/* ---------- annotations ---------- */
.rail-note{
  writing-mode:vertical-rl;
  padding-left:10px;
  border-left:1px solid var(--line);
  font-size:12px;
  letter-spacing:.32em;
  line-height:1.2;
  color:var(--stone);
}
.index-num{
  font-variant-numeric:tabular-nums;
  font-feature-settings:"tnum" 1;
  font-weight:800;
  letter-spacing:.04em;
  color:var(--cyan);
}

/* ---------- responsive ---------- */
@media (max-width:1100px) and (min-width:900px){
  .brand__sub{display:none}
  .nav-steps__link{font-size:16px;padding:7px 9px 5px}
  .nav-steps__badge{display:none}
  .header-cta{padding:9px 14px;font-size:14px}
}

@media (max-width:899px){
  .header-grid{
    display:flex;
    flex-wrap:wrap;
    align-items:center;
    gap:10px;
    padding-block:12px;
  }
  .brand{order:1;flex:1 1 auto}
  .brand__sub{display:none}
  .header-cta{order:2;padding:7px 12px;font-size:12px;letter-spacing:.02em}
  .header-cta::after{display:none}
  .nav-toggle{order:3;display:inline-flex}
  .primary-nav{
    order:4;
    flex:1 1 100%;
    display:none;
    justify-content:stretch;
    margin-top:6px;
    padding-top:8px;
    border-top:1px solid var(--line);
  }
  .site-header[data-open] .primary-nav{display:block}
  .nav-steps{flex-direction:column;align-items:stretch;gap:2px}
  .nav-steps__item{transform:none}
  .nav-steps__link{font-size:17px;padding:12px;border-radius:8px}
  .nav-steps__item--accent{margin-top:8px}
  .nav-steps__badge{display:inline-block}
  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:32px 28px;padding-block:52px 36px}
  .col-4,.col-5,.col-7,.col-8{grid-column:span 12}
  .rail-note{
    writing-mode:horizontal-tb;
    padding:10px 0 0;
    border-left:0;
    border-top:1px solid var(--line);
    letter-spacing:.18em;
  }
}

@media (max-width:640px){
  .footer-grid{grid-template-columns:1fr;gap:28px;padding-block:44px 30px}
  .footer-base{flex-direction:column;align-items:flex-start;gap:6px;padding-block:16px 26px}
  .header-cta{font-size:11px;padding:6px 10px}
  .brand__mark{font-size:19px}
  .tabs__tab{padding:9px 12px;font-size:14px}
}

@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
    scroll-behavior:auto !important;
  }
  .header-progress__bar{transition:none !important}
}