:root{
  --ink-900:#061826;
  --ink-800:#0B2A3D;
  --ink-700:#123A52;
  --cyan:#1EE0CE;
  --cyan-deep:#0FA69C;
  --amber:#F5B33C;
  --coral:#FF6B5A;
  --mist:#F5F8FA;
  --slate:#C4D3DC;
  --ink-text:#16212E;
  --line:rgba(30,224,206,.22);
  --line-soft:rgba(30,224,206,.12);
  --rail-w:96px;
  --bar-h:72px;
  --font-display:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,"Segoe UI",sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono",monospace;
  --ease:cubic-bezier(0.22,0.61,0.36,1);
  --radius:12px;
  color-scheme:light;
}

*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body,h1,h2,h3,h4,h5,p,ul,ol,li,figure,blockquote,dl,dd{margin:0;padding:0}
ul,ol{list-style:none}
a{color:inherit;text-decoration:none}
button{font:inherit;color:inherit;background:none;border:0;cursor:pointer}
img,svg,video{display:block;max-width:100%}
h1,h2,h3,h4{font-family:var(--font-display);font-weight:800;line-height:1.3;letter-spacing:-.01em}
strong,b{font-weight:700}
::selection{background:rgba(30,224,206,.32);color:var(--ink-900)}

:where(a,button,[tabindex]):focus-visible{
  outline:2px solid var(--amber);
  outline-offset:3px;
  border-radius:4px;
}

body{
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.85;
  color:var(--ink-text);
  background:var(--mist);
  padding-top:var(--bar-h);
  padding-left:var(--rail-w);
  -webkit-font-smoothing:antialiased;
  overflow-x:hidden;
}

#main-content{display:block}

/* ---------- skip link ---------- */
.skip-link{
  position:fixed;
  top:10px;
  left:10px;
  z-index:300;
  transform:translateY(-220%);
  background:var(--amber);
  color:#1a1204;
  font-family:var(--font-display);
  font-weight:700;
  font-size:14px;
  padding:10px 18px;
  border-radius:8px;
  transition:transform .18s var(--ease);
}
.skip-link:focus{transform:translateY(0)}

/* ---------- entry bar ---------- */
.site-header{display:contents}

.entry-bar{
  position:fixed;
  inset:0 0 auto 0;
  height:var(--bar-h);
  display:flex;
  align-items:center;
  gap:clamp(10px,2vw,22px);
  padding-right:clamp(12px,2.4vw,32px);
  background:linear-gradient(90deg,rgba(11,42,61,.95),rgba(6,24,38,.94));
  -webkit-backdrop-filter:blur(14px);
  backdrop-filter:blur(14px);
  border-bottom:1px solid var(--line);
  z-index:70;
  transition:background-color .2s var(--ease),box-shadow .2s var(--ease);
}
html.is-scrolled .entry-bar{
  background:linear-gradient(90deg,rgba(11,42,61,.99),rgba(6,24,38,.98));
  box-shadow:0 12px 32px -20px rgba(0,0,0,.95);
}

.entry-bar__mark{
  flex:0 0 var(--rail-w);
  height:100%;
  display:grid;
  place-items:center;
  border-right:1px solid var(--line);
  background:linear-gradient(160deg,rgba(30,224,206,.16),rgba(30,224,206,0) 68%);
}
.mark-glyph{
  display:grid;
  place-items:center;
  width:40px;
  height:40px;
  border-radius:8px;
  border:1px solid rgba(30,224,206,.55);
  background:rgba(30,224,206,.09);
  color:var(--cyan);
  font-family:var(--font-display);
  font-weight:800;
  font-size:20px;
  line-height:1;
  box-shadow:0 0 0 4px rgba(30,224,206,.06);
  transition:color .18s var(--ease),border-color .18s var(--ease),background-color .18s var(--ease);
}
.entry-bar__mark:hover .mark-glyph{
  color:var(--amber);
  border-color:rgba(245,179,60,.7);
  background:rgba(245,179,60,.1);
}

.entry-bar__body{
  display:flex;
  align-items:center;
  gap:12px;
  min-width:0;
  flex:1 1 auto;
}
.entry-bar__kicker{
  font-family:var(--font-display);
  font-weight:700;
  font-size:14px;
  letter-spacing:.02em;
  color:var(--mist);
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.entry-bar__status{
  display:inline-flex;
  align-items:center;
  gap:7px;
  flex:0 0 auto;
  padding:3px 10px;
  border-radius:999px;
  border:1px solid rgba(255,107,90,.42);
  background:rgba(255,107,90,.1);
  color:var(--coral);
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  line-height:1.6;
  white-space:nowrap;
}
.entry-bar__status .dot{
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--coral);
  box-shadow:0 0 0 3px rgba(255,107,90,.18);
  animation:pulse-dot 2.6s var(--ease) infinite;
}
@keyframes pulse-dot{
  0%,100%{opacity:1;box-shadow:0 0 0 3px rgba(255,107,90,.18)}
  50%{opacity:.55;box-shadow:0 0 0 6px rgba(255,107,90,.05)}
}

.entry-bar__cta{margin-left:auto;flex:0 0 auto}

.read-progress{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  height:3px;
  background:rgba(30,224,206,.1);
}
.read-progress__fill{
  display:block;
  height:100%;
  width:0;
  background:linear-gradient(90deg,var(--cyan),var(--amber));
  transition:width .12s linear;
}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;
  align-items:center;
  justify-content:center;
  gap:8px;
  padding:11px 20px;
  border-radius:8px;
  border:1px solid transparent;
  font-family:var(--font-display);
  font-weight:700;
  font-size:14px;
  letter-spacing:.02em;
  line-height:1.4;
  white-space:nowrap;
  transition:background-color .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease),transform .18s var(--ease);
}
.btn--amber{
  background:var(--amber);
  color:#1a1204;
  box-shadow:0 8px 20px -10px rgba(245,179,60,.95);
}
.btn--amber:hover{background:#ffc75c}
.btn--ghost{
  border-color:rgba(30,224,206,.45);
  background:rgba(30,224,206,.08);
  color:var(--cyan);
}
.btn--ghost:hover{background:rgba(30,224,206,.16);border-color:var(--cyan)}

/* ---------- nav toggle ---------- */
.nav-toggle{
  display:none;
  position:fixed;
  top:calc((var(--bar-h) - 40px) / 2);
  right:12px;
  z-index:95;
  width:40px;
  height:40px;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  gap:5px;
  border-radius:10px;
  border:1px solid rgba(30,224,206,.42);
  background:rgba(11,42,61,.92);
  transition:border-color .18s var(--ease),background-color .18s var(--ease);
}
.nav-toggle:hover{border-color:var(--cyan);background:rgba(18,58,82,.95)}
.nav-toggle__bar{
  display:block;
  width:18px;
  height:2px;
  border-radius:2px;
  background:var(--cyan);
  transition:transform .2s var(--ease),opacity .2s var(--ease),background-color .2s var(--ease);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(1){transform:translateY(7px) rotate(45deg);background:var(--amber)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle__bar:nth-child(3){transform:translateY(-7px) rotate(-45deg);background:var(--amber)}

/* ---------- side rail ---------- */
.rail{
  position:fixed;
  top:var(--bar-h);
  left:0;
  bottom:0;
  width:var(--rail-w);
  display:flex;
  flex-direction:column;
  padding:16px 0 10px;
  overflow-y:auto;
  overscroll-behavior:contain;
  background:linear-gradient(180deg,rgba(11,42,61,.97),rgba(6,24,38,.99));
  border-right:1px solid var(--line);
  z-index:65;
  scrollbar-width:thin;
  scrollbar-color:rgba(30,224,206,.35) transparent;
}
.rail::-webkit-scrollbar{width:4px}
.rail::-webkit-scrollbar-thumb{background:rgba(30,224,206,.35);border-radius:2px}

.rail__list{
  display:flex;
  flex-direction:column;
  gap:2px;
  padding:0 8px;
}
.rail__item{display:block}
.rail__link{
  position:relative;
  display:flex;
  flex-direction:column;
  align-items:flex-start;
  gap:1px;
  padding:9px 8px 9px 13px;
  border-radius:6px;
  color:var(--slate);
  transition:color .18s var(--ease),background-color .18s var(--ease);
}
.rail__link::before{
  content:"";
  position:absolute;
  left:0;
  top:50%;
  width:3px;
  height:12px;
  transform:translateY(-50%);
  border-radius:2px;
  background:rgba(196,211,220,.28);
  transition:height .2s var(--ease),background-color .2s var(--ease);
}
.rail__num{
  font-family:var(--font-mono);
  font-size:9px;
  letter-spacing:.1em;
  line-height:1.5;
  color:rgba(196,211,220,.5);
  transition:color .18s var(--ease);
}
.rail__label{
  font-family:var(--font-display);
  font-weight:700;
  font-size:13px;
  line-height:1.45;
  letter-spacing:.01em;
  white-space:nowrap;
}
.rail__link:hover{
  color:var(--mist);
  background:rgba(30,224,206,.08);
}
.rail__link:hover::before{height:20px;background:var(--cyan)}
.rail__link[aria-current="page"]{
  color:var(--amber);
  background:rgba(245,179,60,.1);
}
.rail__link[aria-current="page"]::before{height:28px;background:var(--amber)}
.rail__link[aria-current="page"] .rail__num{color:var(--amber)}

.rail__readout{
  margin-top:auto;
  padding:14px 12px 6px;
  border-top:1px solid var(--line-soft);
  display:flex;
  flex-direction:column;
  gap:2px;
  min-height:64px;
}
.rail__readout-num{
  font-family:var(--font-mono);
  font-size:15px;
  font-weight:700;
  letter-spacing:.06em;
  line-height:1.3;
  color:var(--amber);
}
.rail__readout-label{
  font-size:11px;
  line-height:1.5;
  color:rgba(196,211,220,.62);
}

/* ---------- scrim ---------- */
.nav-scrim{
  position:fixed;
  inset:0;
  z-index:85;
  background:rgba(6,24,38,.66);
  -webkit-backdrop-filter:blur(3px);
  backdrop-filter:blur(3px);
}
.nav-scrim[hidden]{display:none}

/* ---------- generic layout ---------- */
.container{
  width:100%;
  max-width:1180px;
  margin-inline:auto;
  padding-inline:clamp(20px,4vw,56px);
}

.section{padding-block:clamp(44px,6vw,88px);position:relative}
.section--ink{background:var(--ink-900);color:var(--slate)}
.section--ink .section-title{color:var(--mist)}
.section--ink .section-desc{color:rgba(196,211,220,.78)}

.section-head{
  display:flex;
  align-items:baseline;
  gap:clamp(12px,2vw,22px);
  flex-wrap:wrap;
  margin-bottom:clamp(20px,3vw,34px);
  padding-bottom:14px;
  border-bottom:1px solid rgba(18,58,82,.16);
}
.section--ink .section-head{border-bottom-color:var(--line-soft)}
.chapter-num{
  font-family:var(--font-mono);
  font-weight:700;
  font-size:clamp(28px,4vw,54px);
  line-height:1;
  letter-spacing:.04em;
  color:rgba(15,166,156,.55);
}
.section--ink .chapter-num{color:rgba(30,224,206,.5)}
.section-title{
  font-size:clamp(22px,2.6vw,32px);
  color:var(--ink-900);
  margin:0;
}
.section-desc{
  font-size:15px;
  color:#4c6473;
  max-width:62ch;
  margin-top:10px;
  line-height:1.85;
}

/* ---------- breadcrumb ---------- */
.breadcrumb{font-family:var(--font-mono);font-size:12.5px;letter-spacing:.03em;color:#5f7484}
.breadcrumb__list{display:flex;flex-wrap:wrap;align-items:center;gap:8px}
.breadcrumb__list li{display:flex;align-items:center;gap:8px}
.breadcrumb__list li+li::before{content:"/";color:rgba(95,116,132,.55)}
.breadcrumb__list a{color:#37505f;border-bottom:1px solid transparent;transition:color .18s var(--ease),border-color .18s var(--ease)}
.breadcrumb__list a:hover{color:var(--cyan-deep);border-bottom-color:currentColor}
.breadcrumb__list [aria-current="page"]{color:var(--ink-text);font-weight:700}

/* ---------- card ---------- */
.card{
  position:relative;
  display:flex;
  flex-direction:column;
  gap:10px;
  padding:24px 22px 20px;
  border-radius:var(--radius);
  background:#fff;
  border:1px solid #dbe6ec;
  box-shadow:0 1px 0 rgba(18,58,82,.04);
  transition:transform .24s var(--ease),border-color .24s var(--ease),box-shadow .24s var(--ease);
}
.card:hover{
  transform:translateY(-2px);
  border-color:rgba(30,224,206,.5);
  box-shadow:0 18px 34px -26px rgba(6,24,38,.9);
}
.card__num{
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.1em;
  color:var(--cyan-deep);
}
.card__title{font-family:var(--font-display);font-weight:800;font-size:18px;line-height:1.4;color:var(--ink-900)}
.card__desc{font-size:14px;line-height:1.8;color:#4c6473}

/* ---------- grid utilities ---------- */
.grid{display:grid;gap:clamp(14px,2vw,22px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--4{grid-template-columns:repeat(4,minmax(0,1fr))}

/* ---------- media frame ---------- */
.media-frame{
  position:relative;
  overflow:hidden;
  border-radius:var(--radius);
  border:1px solid var(--line);
  background:linear-gradient(140deg,var(--ink-800),var(--ink-900));
  aspect-ratio:16 / 9;
}
.media-frame > img,
.media-frame > svg,
.media-frame > picture{width:100%;height:100%;object-fit:cover}
.media-frame--wide{aspect-ratio:21 / 9}
.media-frame--square{aspect-ratio:1 / 1}
.media-frame--portrait{aspect-ratio:4 / 5}
.media-frame__caption{
  position:absolute;
  left:0;
  right:0;
  bottom:0;
  padding:12px 16px;
  font-size:12.5px;
  line-height:1.6;
  color:var(--slate);
  background:linear-gradient(180deg,rgba(6,24,38,0),rgba(6,24,38,.86));
}

/* ---------- reveal ---------- */
html.js-reveal [data-reveal]{
  opacity:0;
  transform:translateY(8px);
  transition:opacity .24s var(--ease),transform .24s var(--ease);
}
html.js-reveal [data-reveal].is-visible{
  opacity:1;
  transform:none;
}

/* ---------- footer ---------- */
.site-footer{
  position:relative;
  overflow:hidden;
  padding:clamp(46px,6vw,80px) clamp(20px,4vw,56px) 26px;
  background:var(--ink-900);
  color:var(--slate);
  border-top:1px solid var(--line);
  font-size:14px;
  line-height:1.8;
}
.site-footer::before{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:
    radial-gradient(120% 80% at 0% 0%,rgba(30,224,206,.13),transparent 56%),
    radial-gradient(90% 70% at 100% 0%,rgba(245,179,60,.09),transparent 62%);
}
.site-footer::after{
  content:"";
  position:absolute;
  top:0;
  left:0;
  width:100%;
  height:1px;
  pointer-events:none;
  background:linear-gradient(90deg,var(--cyan),rgba(30,224,206,0) 38%,var(--amber));
  opacity:.5;
}
.site-footer > *{position:relative;z-index:1;max-width:1240px;margin-inline:auto}

.footer__grid{
  display:grid;
  grid-template-columns:1fr;
  gap:36px;
}
.footer__mark{
  display:inline-flex;
  align-items:center;
  gap:10px;
  color:var(--mist);
  font-family:var(--font-display);
  font-weight:800;
  font-size:19px;
  letter-spacing:.01em;
}
.footer__mark-glyph{
  display:grid;
  place-items:center;
  width:34px;
  height:34px;
  border-radius:8px;
  border:1px solid rgba(30,224,206,.5);
  background:rgba(30,224,206,.1);
  color:var(--cyan);
  font-size:16px;
  line-height:1;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.footer__mark:hover .footer__mark-glyph{color:var(--amber);border-color:rgba(245,179,60,.7)}
.footer__mark-text{line-height:1.2}

.footer__desc{
  margin-top:14px;
  max-width:34ch;
  font-size:13.5px;
  color:rgba(196,211,220,.82);
}
.footer__meta{
  margin-top:12px;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:var(--cyan);
}
.footer__meta-sep{color:rgba(196,211,220,.35);margin-inline:4px}

.footer__cols{
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:28px 22px;
}
.footer__col-title{
  font-family:var(--font-mono);
  font-weight:600;
  font-size:11px;
  letter-spacing:.14em;
  color:rgba(196,211,220,.62);
  margin-bottom:12px;
}
.footer__list{display:grid;gap:8px}
.footer__link{
  display:inline-block;
  padding:2px 0;
  color:var(--mist);
  font-size:14px;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.footer__link:hover{color:var(--amber);border-bottom-color:rgba(245,179,60,.55)}

.footer__contact{
  margin-top:38px;
  padding-top:24px;
  border-top:1px solid var(--line-soft);
  display:grid;
  gap:8px;
}
.footer__contact-line{
  display:flex;
  flex-wrap:wrap;
  align-items:baseline;
  gap:6px 10px;
  font-size:13.5px;
}
.footer__contact-k{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:rgba(196,211,220,.55);
}
.footer__contact-val{
  font-family:var(--font-mono);
  font-size:13px;
  letter-spacing:.02em;
  color:var(--cyan);
  word-break:break-all;
}
.footer__contact-sep{color:rgba(196,211,220,.3)}
.footer__address{font-size:13px;color:rgba(196,211,220,.8)}
.footer__note{font-size:12.5px;color:rgba(196,211,220,.58);max-width:78ch;line-height:1.75}

.footer__legal{
  margin-top:24px;
  padding-top:18px;
  border-top:1px solid rgba(30,224,206,.14);
  display:flex;
  flex-wrap:wrap;
  gap:8px 22px;
  align-items:center;
  justify-content:space-between;
  font-family:var(--font-mono);
  font-size:11.5px;
  letter-spacing:.06em;
  color:rgba(196,211,220,.55);
}

/* ---------- tablet ---------- */
@media (min-width:720px){
  .footer__grid{grid-template-columns:minmax(240px,1fr) minmax(0,1.9fr);gap:40px}
  .footer__cols{grid-template-columns:repeat(4,minmax(0,1fr))}
}

@media (max-width:900px){
  .entry-bar__kicker{font-size:13px}
}

/* ---------- mobile: rail becomes drawer ---------- */
@media (max-width:1023px){
  :root{--bar-h:60px}
  body{padding-left:0}
  .entry-bar{padding-right:62px;gap:10px}
  .entry-bar__mark{flex:0 0 52px}
  .mark-glyph{width:34px;height:34px;font-size:17px;border-radius:7px}
  .entry-bar__kicker{display:none}
  .entry-bar__cta{padding:8px 13px;font-size:12.5px;border-radius:7px}
  .entry-bar__status{font-size:10px;padding:2px 8px;letter-spacing:.06em}

  .nav-toggle{display:flex}

  .rail{
    top:0;
    width:min(304px,84vw);
    transform:translateX(-102%);
    transition:transform .26s var(--ease);
    padding-top:calc(var(--bar-h) + 14px);
    border-right:1px solid rgba(30,224,206,.35);
    box-shadow:0 0 70px rgba(0,0,0,.62);
    z-index:90;
  }
  .rail[data-open]{transform:translateX(0)}
  .rail__list{padding:0 14px;gap:4px}
  .rail__link{
    flex-direction:row;
    align-items:center;
    gap:12px;
    padding:13px 14px 13px 18px;
    border-radius:8px;
  }
  .rail__link::before{height:22px}
  .rail__num{font-size:11px}
  .rail__label{font-size:16px;white-space:normal}
  .rail__link[aria-current="page"]::before{height:30px}
  .rail__readout{padding:16px 20px 10px}

  html.nav-open{overflow:hidden}
}

@media (max-width:640px){
  .entry-bar__status{display:none}
  .footer__cols{grid-template-columns:repeat(2,minmax(0,1fr))}
  .section{padding-block:clamp(34px,8vw,56px)}
}

/* ---------- motion preference ---------- */
@media (prefers-reduced-motion:reduce){
  *,*::before,*::after{
    animation-duration:.01ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.01ms !important;
    scroll-behavior:auto !important;
  }
  .skip-link{transition:none}
  html.js-reveal [data-reveal]{opacity:1;transform:none}
}