/* ========== reset ========== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
img,svg,video{display:block;max-width:100%}
button,input,select,textarea{font:inherit;color:inherit}
button{background:none;border:0;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}

/* ========== tokens ========== */
:root{
  --sea:#061A2B;
  --ship:#0B2A42;
  --panel:#103A55;
  --edge:#1B5670;
  --cyan:#2FE3C8;
  --gold:#D8B25A;
  --amber:#E8943A;
  --mist:#E8F1F4;
  --mist-2:#A8C3CC;
  --mist-3:#7E9AA6;
  --ink:#04222B;
  --font-sans:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --wrap:1160px;
  --pad:clamp(16px,4vw,40px);
  --shadow-hard:8px 8px 0 rgba(2,12,20,.55);
  --shadow-soft:4px 4px 0 rgba(2,12,20,.45);
  --t:220ms cubic-bezier(.2,.7,.3,1);
}

/* ========== base ========== */
body{
  background:var(--sea);
  color:var(--mist);
  font-family:var(--font-sans);
  font-size:16px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}
h1,h2,h3,h4,h5{font-weight:700;letter-spacing:-.02em;line-height:1.16}
h1{font-size:clamp(34px,6vw,68px)}
h2{font-size:clamp(24px,3.4vw,37px)}
h3{font-size:clamp(18px,2vw,23px)}
h4{font-size:17px}
p{max-width:70ch}
small{font-size:13px}
#main-content{display:block}
::selection{background:var(--cyan);color:var(--ink)}

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

/* ========== utilities ========== */
.container{width:100%;max-width:var(--wrap);margin-inline:auto;padding-inline:var(--pad)}
.container--narrow{max-width:820px}
.mono{font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;color:var(--mist-2)}
.kicker{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-mono);font-size:12px;letter-spacing:.2em;text-transform:uppercase;color:var(--gold)}
.kicker::before{content:"";width:26px;height:2px;background:var(--gold);flex:0 0 auto}
.lede{font-size:clamp(16px,1.6vw,19px);line-height:1.8;color:var(--mist-2);max-width:62ch}
.section{padding-block:clamp(38px,6vw,84px)}
.band{height:4px;border:0;margin-block:clamp(26px,5vw,54px);background:linear-gradient(90deg,var(--gold),var(--cyan) 58%,rgba(47,227,200,0) 100%)}

/* ========== skip link ========== */
.skip-link{
  position:fixed;top:10px;left:10px;z-index:200;
  padding:10px 16px;background:var(--cyan);color:var(--ink);
  border:2px solid var(--ink);font-family:var(--font-mono);font-size:13px;letter-spacing:.06em;
  transform:translateY(-180%);transition:transform var(--t);
}
.skip-link:focus{transform:translateY(0)}

/* ========== header ========== */
.site-header{
  position:sticky;top:0;z-index:80;
  background:var(--sea);
  border-bottom:2px solid var(--edge);
}
.status-strip{background:var(--ship);border-bottom:1px solid var(--edge)}
.status-strip__inner{
  display:flex;align-items:center;gap:clamp(10px,2vw,20px);flex-wrap:wrap;
  min-height:40px;padding-block:6px;
}
.status-strip__note{display:inline-flex;align-items:center;gap:8px;flex:0 0 auto;max-width:none;
  font-family:var(--font-mono);font-size:12px;letter-spacing:.08em;color:var(--mist-2)}
.status-strip__label{color:var(--mist)}
.status-strip__ver{color:var(--gold)}
.status-dot{
  width:8px;height:8px;border-radius:50%;flex:0 0 auto;
  background:var(--cyan);box-shadow:0 0 0 3px rgba(47,227,200,.16);
  animation:dotPulse 3.4s ease-in-out infinite;
}
@keyframes dotPulse{0%,100%{opacity:1;transform:scale(1)}50%{opacity:.5;transform:scale(.84)}}
.status-strip__hint{flex:1 1 220px;max-width:none;font-size:12.5px;line-height:1.5;color:var(--mist-3)}
.status-strip__hint [hidden]{display:none}
.switch-set{
  display:inline-flex;flex:0 0 auto;gap:2px;padding:2px;
  border:1px solid var(--edge);background:rgba(6,26,43,.65);
}
.switch-btn{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;
  padding:5px 10px;color:var(--mist-3);border:1px solid transparent;
  transition:color var(--t),background var(--t),border-color var(--t);
}
.switch-btn:hover{color:var(--mist)}
.switch-btn.is-active{background:var(--cyan);border-color:var(--cyan);color:var(--ink)}
.switch-btn.is-active:hover{color:var(--ink)}
.status-strip__cta{
  flex:0 0 auto;font-family:var(--font-mono);font-size:12px;letter-spacing:.06em;
  color:var(--cyan);border-bottom:1px solid rgba(47,227,200,.45);padding-bottom:2px;
  transition:color var(--t),border-color var(--t);
}
.status-strip__cta:hover{color:var(--gold);border-color:var(--gold)}

.cmd-bar{background:var(--sea)}
.cmd-bar__inner{display:flex;align-items:center;gap:clamp(12px,2vw,28px);min-height:66px}

.brand{display:inline-flex;align-items:center;gap:10px;flex:0 0 auto}
.brand__mark{
  display:grid;place-items:center;width:38px;height:38px;flex:0 0 auto;
  border:2px solid var(--gold);color:var(--gold);
  background:linear-gradient(160deg,var(--panel),var(--ship));
  box-shadow:3px 3px 0 rgba(2,12,20,.5);
  font-family:var(--font-mono);font-size:16px;font-weight:700;letter-spacing:.04em;
}
.brand__text{display:flex;flex-direction:column;line-height:1.1}
.brand__name{font-size:19px;font-weight:700;letter-spacing:.06em;color:var(--mist)}
.brand__meta{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.16em;color:var(--mist-3);margin-top:4px}

.site-nav{display:flex;align-items:center;gap:clamp(6px,1.4vw,16px);margin-left:auto}
.site-nav__list{display:flex;align-items:center;gap:clamp(2px,.6vw,8px)}
.site-nav__link{
  display:inline-flex;align-items:flex-start;gap:6px;padding:8px 10px;
  border-bottom:2px solid transparent;color:var(--mist-2);
  transition:color var(--t),border-color var(--t),background var(--t);
}
.site-nav__idx{font-family:var(--font-mono);font-size:10px;letter-spacing:.06em;line-height:1.9;color:var(--mist-3);transition:color var(--t)}
.site-nav__label{font-size:14px;font-weight:600;letter-spacing:.02em;white-space:nowrap}
.site-nav__link:hover{color:var(--mist);background:rgba(47,227,200,.06)}
.site-nav__link:hover .site-nav__idx{color:var(--cyan)}
.site-nav__link[aria-current="page"]{color:var(--cyan);border-bottom-color:var(--gold)}
.site-nav__link[aria-current="page"] .site-nav__idx{color:var(--gold)}
.site-nav__cta{margin-left:8px}

.nav-toggle{
  display:none;align-items:center;gap:8px;margin-left:auto;padding:9px 12px;
  border:2px solid var(--edge);background:var(--panel);color:var(--mist);
  font-family:var(--font-mono);font-size:12px;letter-spacing:.1em;
  box-shadow:3px 3px 0 rgba(2,12,20,.5);
}
.nav-toggle__bars{display:inline-flex;flex-direction:column;gap:3px;width:16px}
.nav-toggle__bars span{display:block;height:2px;background:var(--cyan);transition:transform var(--t),opacity var(--t)}
.nav-toggle__text{line-height:1}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1){transform:translateY(5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3){transform:translateY(-5px) rotate(-45deg)}

.nav-scrim{display:none;position:fixed;inset:0;z-index:55;background:rgba(3,14,22,.68)}

.read-progress{position:absolute;left:0;right:0;bottom:-2px;height:2px;overflow:hidden;background:rgba(27,86,112,.35)}
.read-progress__fill{display:block;height:100%;width:0;background:linear-gradient(90deg,var(--gold),var(--cyan));transition:width .12s linear}

/* ========== buttons ========== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  padding:12px 20px;border:2px solid var(--edge);
  font-family:var(--font-sans);font-size:14px;font-weight:600;letter-spacing:.02em;
  color:var(--mist);background:rgba(16,58,85,.35);
  box-shadow:var(--shadow-soft);
  transition:transform var(--t),box-shadow var(--t),background var(--t),color var(--t),border-color var(--t);
}
.btn:hover{transform:translate(-1px,-1px);box-shadow:6px 6px 0 rgba(2,12,20,.5)}
.btn:active{transform:translate(0,0);box-shadow:2px 2px 0 rgba(2,12,20,.5)}
.btn--primary{background:var(--cyan);border-color:var(--cyan);color:var(--ink)}
.btn--primary:hover{background:#4df0d8;border-color:#4df0d8}
.btn--ghost{background:rgba(11,42,66,.6);border-color:var(--edge);color:var(--mist)}
.btn--ghost:hover{border-color:var(--cyan);color:var(--cyan)}
.btn--quiet{border-color:transparent;background:none;box-shadow:none;color:var(--mist-2);padding-inline:10px}
.btn--quiet:hover{color:var(--cyan);box-shadow:none;transform:none}

/* ========== panels & cabins ========== */
.panel{
  background:var(--panel);border:2px solid var(--edge);
  box-shadow:var(--shadow-hard);padding:clamp(20px,3vw,34px);
}
.panel__head{
  display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;
  padding-bottom:14px;margin-bottom:18px;border-bottom:1px solid var(--edge);
}
.panel__title{font-size:clamp(18px,2vw,22px);letter-spacing:-.01em;color:var(--mist)}
.panel__body{font-size:15px;line-height:1.75;color:var(--mist-2)}
.panel__body p + p{margin-top:12px}
.cabin{
  position:relative;background:var(--ship);border:2px solid var(--edge);border-left:4px solid var(--gold);
  box-shadow:var(--shadow-soft);padding:clamp(18px,2.6vw,26px);
}

/* ========== chips ========== */
.chip{
  display:inline-flex;align-items:center;gap:6px;
  padding:4px 9px;border:1px solid var(--edge);background:rgba(16,58,85,.6);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--mist-2);
}
.chip--gold{color:var(--gold);border-color:rgba(216,178,90,.5)}
.chip--amber{color:var(--amber);border-color:rgba(232,148,58,.55);background:rgba(232,148,58,.08)}

/* ========== media frame ========== */
.media-frame{
  position:relative;overflow:hidden;aspect-ratio:16/9;
  border:2px solid var(--edge);box-shadow:var(--shadow-hard);
  background:
    radial-gradient(120% 90% at 18% 8%,rgba(47,227,200,.14),rgba(47,227,200,0) 62%),
    repeating-linear-gradient(90deg,rgba(27,86,112,.45) 0 1px,rgba(27,86,112,0) 1px 44px),
    repeating-linear-gradient(0deg,rgba(27,86,112,.32) 0 1px,rgba(27,86,112,0) 1px 44px),
    linear-gradient(160deg,#0B2A42,#061A2B 72%);
}
.media-frame img{width:100%;height:100%;object-fit:cover}
.media-frame--wide{aspect-ratio:21/9}
.media-frame--tall{aspect-ratio:4/5}
.media-frame__caption{
  position:absolute;left:0;right:0;bottom:0;padding:10px 14px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.08em;color:var(--mist-2);
  background:linear-gradient(0deg,rgba(6,26,43,.94),rgba(6,26,43,0));
}

/* ========== grids ========== */
.grid{display:grid;gap:clamp(16px,2.6vw,28px)}
.grid--2{grid-template-columns:repeat(auto-fit,minmax(280px,1fr))}
.grid--3{grid-template-columns:repeat(auto-fit,minmax(240px,1fr))}
.split{display:grid;grid-template-columns:1.15fr .85fr;gap:clamp(20px,4vw,48px);align-items:start}

/* ========== breadcrumb ========== */
.breadcrumb{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px;padding-block:14px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.06em;color:var(--mist-3);
}
.breadcrumb__item{display:inline-flex;align-items:center;gap:8px}
.breadcrumb__link{color:var(--mist-2);transition:color var(--t)}
.breadcrumb__link:hover{color:var(--cyan)}
.breadcrumb__sep{color:var(--edge)}

/* ========== path list & copy ========== */
.path-list{display:flex;flex-direction:column;border-top:1px solid var(--edge)}
.path-list__item{
  display:flex;align-items:center;justify-content:space-between;gap:14px;flex-wrap:wrap;
  padding:12px 14px 12px 16px;border-bottom:1px solid var(--edge);border-left:3px solid transparent;
  font-family:var(--font-mono);font-size:13px;letter-spacing:.04em;color:var(--mist);
  transition:border-color var(--t),background var(--t);
}
.path-list__item:hover{border-left-color:var(--cyan);background:rgba(47,227,200,.06)}
.copy-btn{
  flex:0 0 auto;padding:6px 10px;border:1px solid var(--edge);background:rgba(6,26,43,.55);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.1em;color:var(--mist-2);
  transition:color var(--t),border-color var(--t),background var(--t);
}
.copy-btn:hover{color:var(--cyan);border-color:var(--cyan)}
.copy-btn.is-copied{background:var(--cyan);border-color:var(--cyan);color:var(--ink)}

/* ========== fold ========== */
.fold{border:2px solid var(--edge);background:rgba(16,58,85,.45)}
.fold + .fold{margin-top:-2px}
.fold__summary{
  display:flex;align-items:center;justify-content:space-between;gap:14px;
  padding:14px 18px;cursor:pointer;font-size:15px;font-weight:600;color:var(--mist);
  list-style:none;transition:background var(--t);
}
.fold__summary::-webkit-details-marker{display:none}
.fold__summary::after{content:"+";font-family:var(--font-mono);font-size:16px;color:var(--cyan)}
.fold[open] .fold__summary::after{content:"−"}
.fold__summary:hover{background:rgba(47,227,200,.06)}
.fold__body{padding:0 18px 18px;font-size:14.5px;line-height:1.75;color:var(--mist-2)}

/* ========== reveal ========== */
[data-reveal]{opacity:0;transform:translateY(14px);transition:opacity var(--t),transform var(--t)}
[data-reveal].is-in{opacity:1;transform:none}

/* ========== footer ========== */
.site-footer{background:var(--ship);border-top:2px solid var(--edge);color:var(--mist-2)}
.footer__grid{
  display:grid;grid-template-columns:1.5fr 1fr 1fr 1fr;
  gap:clamp(24px,4vw,48px);padding-block:clamp(34px,5vw,62px);
}
.footer__brand{display:flex;flex-direction:column;gap:14px;min-width:0}
.brand--footer .brand__name{font-size:18px}
.footer__tagline{font-size:13.5px;line-height:1.7;color:var(--mist-3);max-width:26ch}
.footer__mono{font-family:var(--font-mono);font-size:11.5px;letter-spacing:.1em;color:var(--cyan);max-width:none}
.footer__col{min-width:0}
.footer__col-title{
  font-family:var(--font-mono);font-size:11px;letter-spacing:.18em;text-transform:uppercase;
  color:var(--gold);margin-bottom:14px;padding-bottom:8px;border-bottom:1px solid var(--edge);max-width:none;
}
.footer__links{display:flex;flex-direction:column;gap:9px}
.footer__link{font-size:14px;color:var(--mist-2);transition:color var(--t)}
.footer__link:hover{color:var(--cyan)}
.footer__contact{
  display:flex;flex-direction:column;gap:8px;margin-top:6px;padding-top:18px;
  border-top:1px dashed var(--edge);font-size:13px;color:var(--mist-3);
}
.contact-row{display:flex;gap:10px;flex-wrap:wrap}
.contact-row__key{
  min-width:44px;flex:0 0 auto;font-family:var(--font-mono);font-size:11px;
  letter-spacing:.12em;color:var(--mist-3);
}
.contact-row__val{font-size:13.5px;color:var(--mist);word-break:break-word}
.footer__note{margin-top:14px;font-size:12.5px;line-height:1.7;color:var(--mist-3);max-width:66ch}
.footer__legal{border-top:1px solid var(--edge)}
.footer__legal-inner{
  display:flex;flex-wrap:wrap;align-items:center;gap:8px 20px;padding-block:18px 34px;
  font-family:var(--font-mono);font-size:11.5px;letter-spacing:.06em;color:var(--mist-3);
}

/* ========== responsive ========== */
@media (max-width:1180px){
  .site-nav__idx{display:none}
  .site-nav__label{font-size:13px}
  .site-nav__link{padding:8px 8px}
}
@media (max-width:1024px){
  .cmd-bar__inner{min-height:58px}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:fixed;top:0;right:0;bottom:0;z-index:60;
    width:min(86vw,340px);margin-left:0;
    display:flex;flex-direction:column;align-items:stretch;gap:8px;
    padding:88px 22px 32px;overflow-y:auto;
    background:var(--ship);border-left:2px solid var(--edge);
    box-shadow:-14px 0 0 rgba(2,12,20,.4);
    transform:translateX(104%);transition:transform var(--t);
  }
  .site-nav[data-open="true"]{transform:translateX(0)}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:0}
  .site-nav__link{display:flex;align-items:center;gap:12px;padding:14px 6px;border-bottom:1px solid rgba(27,86,112,.75)}
  .site-nav__idx{display:inline-block;font-size:11px}
  .site-nav__label{font-size:16px}
  .site-nav__link[aria-current="page"]{border-bottom-color:rgba(216,178,90,.85);background:rgba(47,227,200,.07)}
  .site-nav__cta{margin:18px 0 0;width:100%;padding-block:14px}
  .site-header[data-open="true"] .nav-scrim{display:block}
  .split{grid-template-columns:1fr}
  .footer__grid{grid-template-columns:1fr 1fr}
}
@media (max-width:720px){
  .status-strip__hint{display:none}
  .status-strip__cta{font-size:11px}
  .brand__name{font-size:17px}
  .brand__mark{width:34px;height:34px;font-size:15px}
  .footer__grid{grid-template-columns:1fr;gap:28px}
  .footer__legal-inner{padding-block:16px 28px}
}
@media (max-width:400px){
  .switch-btn{padding:5px 7px;font-size:10.5px}
  .status-strip__label{display:none}
}

/* ========== motion preferences ========== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  [data-reveal]{opacity:1;transform:none}
  .read-progress__fill{transition:none}
}