:root{
  --ink-900:#0B1626;
  --ink-800:#12243A;
  --ink-700:#17304C;
  --signal:#FF5A36;
  --signal-soft:#FF8A6B;
  --teal:#2FB8A6;
  --teal-glow:#8BE6D8;
  --paper:#F6F2E8;
  --mist:#AEBACA;
  --line:#2C4058;
  --amber:#F2C14E;

  --rail-w:318px;
  --shell-max:1180px;
  --edge:clamp(1.15rem, 4vw, 2.75rem);
  --measure:72ch;

  --font-body:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans SC","Microsoft YaHei","Heiti SC",system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;
  --font-display:"PingFang SC","Hiragino Sans GB","Source Han Sans SC","Noto Sans SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:ui-monospace,SFMono-Regular,"SF Mono",Menlo,Consolas,"Liberation Mono","Courier New",monospace;

  --ease:cubic-bezier(.22,.61,.36,1);
  --dur:180ms;
}

*,
*::before,
*::after{box-sizing:border-box}

html{
  -webkit-text-size-adjust:100%;
  scroll-behavior:smooth;
  scroll-padding-top:5.6rem;
}

body{
  margin:0;
  min-height:100vh;
  background:var(--ink-900);
  color:var(--paper);
  font-family:var(--font-body);
  font-size:clamp(0.96rem, 0.35vw + 0.9rem, 1.06rem);
  line-height:1.75;
  letter-spacing:0.005em;
  -webkit-font-smoothing:antialiased;
  text-rendering:optimizeLegibility;
}

h1,h2,h3,h4,h5,h6,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{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
a{color:inherit;text-decoration:none}
table{border-collapse:collapse;width:100%}

:where(a,button,summary,input,textarea,select):focus-visible{
  outline:2px solid var(--teal-glow);
  outline-offset:3px;
  border-radius:3px;
}

::selection{background:var(--signal);color:var(--ink-900)}

/* ===== utilities ===== */
.shell{
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding-inline:var(--edge);
}

.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}

.eyebrow{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:600;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--teal-glow);
}

.display{
  font-family:var(--font-display);
  font-size:clamp(2.4rem, 6.4vw, 4.6rem);
  font-weight:300;
  line-height:.98;
  letter-spacing:-.02em;
  color:var(--paper);
}

.display--tight{
  font-weight:600;
  letter-spacing:-.035em;
  line-height:1.04;
}

.lede{
  max-width:var(--measure);
  font-size:clamp(1rem, 0.4vw + 0.94rem, 1.12rem);
  line-height:1.8;
  color:var(--mist);
}

.prose{
  max-width:var(--measure);
  font-size:1rem;
  line-height:1.86;
  color:var(--paper);
}
.prose p + p{margin-top:1em}
.prose a{color:var(--teal-glow);border-bottom:1px solid rgba(139,230,216,.4)}
.prose a:hover{border-bottom-color:var(--teal-glow)}
.prose ul,.prose ol{margin-block:.85em;padding-left:1.35em;list-style:disc}
.prose ol{list-style:decimal}
.prose li + li{margin-top:.35em}

.rule{
  height:1px;
  border:0;
  margin-block:2rem;
  background:var(--line);
}

.signal-band{
  height:4px;
  width:100%;
  border:0;
  background:linear-gradient(90deg,var(--signal) 0 30%, var(--amber) 30% 46%, var(--teal) 46% 72%, var(--line) 72% 100%);
}

.stack{display:flex;flex-direction:column;gap:1rem}

.grid{display:grid;gap:1.1rem}
.grid--2{grid-template-columns:minmax(0,1fr)}
.grid--3{grid-template-columns:minmax(0,1fr)}

.breadcrumbs{
  display:flex;
  flex-wrap:wrap;
  gap:.45rem;
  padding-block:1.15rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--mist);
}
.breadcrumbs li{display:flex;align-items:center;gap:.45rem}
.breadcrumbs li:not(:first-child)::before{content:"/";color:var(--line)}
.breadcrumbs a{color:var(--mist);transition:color var(--dur) var(--ease)}
.breadcrumbs a:hover{color:var(--teal-glow)}

.btn{
  display:inline-flex;
  align-items:center;
  gap:.55rem;
  padding:.7rem 1.15rem;
  border:1px solid var(--line);
  border-radius:4px;
  font-size:.9rem;
  letter-spacing:.02em;
  color:var(--paper);
  background:transparent;
  transition:background var(--dur) var(--ease),border-color var(--dur) var(--ease),color var(--dur) var(--ease),transform var(--dur) var(--ease);
}
.btn:hover,
.btn:focus-visible{
  transform:translateY(-1px);
  border-color:var(--teal);
  color:var(--teal-glow);
}
.btn--signal{
  background:var(--signal);
  border-color:var(--signal);
  color:var(--ink-900);
  font-weight:600;
}
.btn--signal:hover,
.btn--signal:focus-visible{
  background:var(--amber);
  border-color:var(--amber);
  color:var(--ink-900);
}
.btn--ghost{
  background:rgba(18,36,58,.7);
  border-color:var(--line);
}

.chip{
  display:inline-flex;
  align-items:center;
  gap:.4rem;
  padding:.28rem .62rem;
  border:1px solid var(--line);
  border-radius:999px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:600;
  letter-spacing:.12em;
  color:var(--mist);
  white-space:nowrap;
}
.tag--signal{background:var(--signal);border-color:var(--signal);color:var(--ink-900)}
.tag--teal{background:var(--teal);border-color:var(--teal);color:var(--ink-900)}
.tag--amber{background:var(--amber);border-color:var(--amber);color:var(--ink-900)}

.card{
  position:relative;
  padding:1.2rem 1.25rem 1.35rem;
  background:var(--ink-800);
  border:1px solid var(--line);
  border-radius:6px;
  box-shadow:0 18px 40px -38px #000;
  transition:border-color var(--dur) var(--ease),transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.card:hover{
  border-color:#3B5878;
  transform:translateY(-2px);
  box-shadow:0 22px 44px -36px #000;
}

.media{
  position:relative;
  display:block;
  overflow:hidden;
  isolation:isolate;
  aspect-ratio:16 / 10;
  border:1px solid var(--line);
  border-radius:6px;
  background:linear-gradient(150deg,#16304D 0%, var(--ink-800) 46%, #0A1524 100%);
}
.media > img,
.media > picture,
.media > picture > img{
  display:block;
  width:100%;
  height:100%;
  object-fit:cover;
}
.media--wide{aspect-ratio:21 / 9}
.media--tall{aspect-ratio:4 / 5}
.media--square{aspect-ratio:1 / 1}
.media--grain::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  opacity:.55;
  background-image:
    repeating-linear-gradient(90deg, rgba(246,242,232,.07) 0 1px, transparent 1px 4px),
    repeating-linear-gradient(0deg, rgba(11,22,38,.38) 0 1px, transparent 1px 3px);
}
.media-caption{
  margin-top:.55rem;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--mist);
}

.section{padding-block:clamp(2.2rem, 5vw, 4.2rem)}
.section--band{
  background:var(--ink-800);
  border-block:1px solid var(--line);
}
.section-head{
  display:flex;
  flex-direction:column;
  gap:.55rem;
  margin-bottom:1.5rem;
}

/* ===== skip link ===== */
.skip-link{
  position:fixed;
  top:.7rem;
  left:.7rem;
  z-index:400;
  padding:.55rem .95rem;
  border-radius:4px;
  background:var(--amber);
  color:var(--ink-900);
  font-size:.85rem;
  font-weight:600;
  letter-spacing:.06em;
  transform:translateY(-180%);
  transition:transform var(--dur) var(--ease);
}
.skip-link:focus-visible{transform:translateY(0)}

/* ===== header ===== */
.site-header{
  position:sticky;
  top:0;
  z-index:80;
  background:var(--ink-900);
  border-bottom:1px solid var(--line);
  box-shadow:0 14px 32px -30px #000;
}
.site-header::after{
  content:"";
  position:absolute;
  left:0;
  bottom:0;
  height:2px;
  width:calc(var(--scroll-progress, 0) * 1%);
  max-width:100%;
  pointer-events:none;
  background:linear-gradient(90deg, var(--signal), var(--amber) 52%, var(--teal));
  transition:width .08s linear;
}

.header-shell{
  display:flex;
  flex-direction:column;
  gap:.75rem;
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding:.7rem var(--edge) .9rem;
}

.header-bar{
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:1rem;
}

.brand{
  display:inline-flex;
  align-items:center;
  gap:.65rem;
  min-width:0;
}

.brand-glyph{
  position:relative;
  flex:0 0 36px;
  width:36px;
  height:36px;
  border-radius:10px;
  overflow:hidden;
  background:linear-gradient(155deg, var(--signal-soft) 0%, var(--signal) 46%, #C8341B 100%);
  box-shadow:0 8px 20px -12px rgba(255,90,54,.95), inset 0 0 0 1px rgba(246,242,232,.22);
}
.brand-glyph::before,
.brand-glyph::after{
  content:"";
  position:absolute;
  top:50%;
  width:4px;
  height:14px;
  border-radius:1px;
  background:var(--paper);
  transform:translateY(-50%) skewX(-16deg);
}
.brand-glyph::before{left:11px;opacity:.92}
.brand-glyph::after{right:11px;background:var(--teal-glow)}

.brand-copy{display:flex;flex-direction:column;line-height:1.1;min-width:0}
.brand-name{
  font-family:var(--font-display);
  font-size:1.12rem;
  font-weight:600;
  letter-spacing:.06em;
  color:var(--paper);
}
.brand-sub{
  margin-top:.3rem;
  font-family:var(--font-mono);
  font-size:10px;
  letter-spacing:.22em;
  text-transform:uppercase;
  color:var(--mist);
}

.nav-toggle{
  display:inline-flex;
  align-items:center;
  gap:.55rem;
  flex:0 0 auto;
  padding:.45rem .72rem .45rem .62rem;
  border:1px solid var(--line);
  border-radius:5px;
  background:rgba(18,36,58,.92);
  color:var(--paper);
  font-size:.78rem;
  letter-spacing:.14em;
  transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease),color var(--dur) var(--ease);
}
.nav-toggle:hover,
.nav-toggle:focus-visible{
  border-color:var(--signal);
  color:var(--signal-soft);
}
.nav-toggle[aria-expanded="true"]{
  border-color:var(--teal);
  color:var(--teal-glow);
  background:rgba(47,184,166,.12);
}

.nav-toggle-icon{
  position:relative;
  display:block;
  width:16px;
  height:10px;
  background:linear-gradient(currentColor, currentColor) center / 100% 1.5px no-repeat;
}
.nav-toggle-icon::before,
.nav-toggle-icon::after{
  content:"";
  position:absolute;
  left:0;
  right:0;
  height:1.5px;
  background:currentColor;
  transition:transform var(--dur) var(--ease),opacity var(--dur) var(--ease);
}
.nav-toggle-icon::before{top:0}
.nav-toggle-icon::after{bottom:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon{background:transparent}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon::before{transform:translateY(4.25px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-icon::after{transform:translateY(-4.25px) rotate(-45deg)}

/* ===== nav ===== */
.site-nav{
  display:flex;
  flex-direction:column;
  gap:1.1rem;
  min-height:0;
  padding-top:.9rem;
  border-top:1px solid var(--line);
}

.nav-list{display:flex;flex-direction:column;gap:3px}

.nav-item{display:block}

.nav-link{
  display:grid;
  grid-template-columns:2.1rem minmax(0,1fr);
  align-items:center;
  gap:.5rem;
  padding:.6rem .7rem;
  border:1px solid transparent;
  border-left:2px solid transparent;
  border-radius:4px;
  color:var(--mist);
  transition:color var(--dur) var(--ease),background var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.nav-index{
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:700;
  letter-spacing:.12em;
  color:rgba(174,186,202,.42);
  transition:color var(--dur) var(--ease);
}
.nav-label{
  font-size:.94rem;
  letter-spacing:.02em;
  white-space:nowrap;
  overflow:hidden;
  text-overflow:ellipsis;
}
.nav-link:hover,
.nav-link:focus-visible{
  color:var(--paper);
  background:rgba(47,184,166,.08);
  border-color:rgba(47,184,166,.28);
}
.nav-link:hover .nav-index{color:var(--teal)}
.nav-link[aria-current="page"]{
  color:var(--paper);
  background:linear-gradient(100deg, rgba(255,90,54,.18), rgba(255,90,54,.02) 78%);
  border-color:rgba(255,90,54,.24);
  border-left-color:var(--signal);
}
.nav-link[aria-current="page"] .nav-index{color:var(--signal-soft)}
.nav-link[aria-current="page"] .nav-label{font-weight:600}

.nav-aside{
  padding:.85rem .9rem 1rem;
  border:1px solid var(--line);
  border-top:2px solid var(--teal);
  border-radius:2px 2px 6px 6px;
  background:linear-gradient(180deg, rgba(47,184,166,.12), rgba(18,36,58,.6) 42%, rgba(11,22,38,.25));
  box-shadow:0 16px 32px -30px #000;
}
.nav-aside-title{
  margin-bottom:.55rem;
  font-family:var(--font-mono);
  font-size:10.5px;
  font-weight:700;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--teal-glow);
}
.nav-aside-list{display:flex;flex-direction:column}
.nav-aside-list li + li{margin-top:.1rem}
.nav-aside-list a{
  display:block;
  padding:.34rem 0;
  font-size:.82rem;
  line-height:1.5;
  color:var(--mist);
  border-bottom:1px dashed rgba(44,64,88,.75);
  transition:color var(--dur) var(--ease),padding-left var(--dur) var(--ease);
}
.nav-aside-list li:last-child a{border-bottom:0}
.nav-aside-list a:hover,
.nav-aside-list a:focus-visible{color:var(--paper);padding-left:.35rem}

.nav-util{
  display:flex;
  flex-direction:column;
  gap:.8rem;
  margin-top:.4rem;
}

.nav-quick{
  display:flex;
  flex-wrap:wrap;
  gap:.4rem;
}
.quick-chip{
  display:inline-block;
  padding:.3rem .62rem;
  border:1px solid var(--line);
  border-radius:999px;
  font-size:.76rem;
  letter-spacing:.06em;
  color:var(--mist);
  transition:color var(--dur) var(--ease),background var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.quick-chip:hover,
.quick-chip:focus-visible{
  background:var(--amber);
  border-color:var(--amber);
  color:var(--ink-900);
}

.header-account{
  display:inline-flex;
  align-items:center;
  gap:.55rem;
  padding:.68rem .85rem;
  border:1px solid rgba(255,90,54,.42);
  border-radius:5px;
  background:rgba(255,90,54,.12);
  color:var(--paper);
  font-size:.82rem;
  letter-spacing:.04em;
  transition:background var(--dur) var(--ease),border-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.header-account-dot{
  flex:0 0 6px;
  width:6px;
  height:6px;
  border-radius:50%;
  background:var(--signal);
  box-shadow:0 0 0 3px rgba(255,90,54,.18);
}
.header-account:hover,
.header-account:focus-visible{
  background:var(--signal);
  border-color:var(--signal);
  color:var(--ink-900);
}
.header-account:hover .header-account-dot,
.header-account:focus-visible .header-account-dot{background:var(--ink-900);box-shadow:none}

/* ===== footer ===== */
.site-footer{
  position:relative;
  margin-top:clamp(3rem, 6vw, 5.5rem);
  background:var(--ink-800);
  border-top:1px solid var(--line);
}
.footer-signal{
  height:5px;
  background:linear-gradient(90deg, var(--signal) 0 22%, var(--amber) 22% 34%, var(--teal) 34% 58%, var(--line) 58% 100%);
}

.footer-inner{
  display:grid;
  grid-template-columns:minmax(0,1fr);
  gap:2rem;
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding:clamp(2rem, 4vw, 3.1rem) var(--edge) clamp(1.7rem, 3vw, 2.5rem);
}

.footer-brand{display:flex;flex-direction:column}
.footer-brand-link{
  font-family:var(--font-display);
  font-size:1.42rem;
  font-weight:600;
  letter-spacing:.05em;
  color:var(--paper);
  transition:color var(--dur) var(--ease);
}
.footer-brand-link:hover,
.footer-brand-link:focus-visible{color:var(--signal-soft)}
.footer-brand-line{
  margin-top:.45rem;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:600;
  letter-spacing:.24em;
  color:var(--signal-soft);
}
.footer-region{
  margin-top:.7rem;
  font-size:.8rem;
  letter-spacing:.04em;
  color:var(--mist);
}
.footer-region + .footer-region{margin-top:.2rem}

.footer-nav{
  display:grid;
  grid-template-columns:repeat(2, minmax(0,1fr));
  gap:1.4rem;
}
.footer-nav-title{
  margin-bottom:.7rem;
  font-family:var(--font-mono);
  font-size:10.5px;
  font-weight:700;
  letter-spacing:.2em;
  text-transform:uppercase;
  color:var(--teal-glow);
}
.footer-nav-links{display:flex;flex-direction:column;gap:.2rem}
.footer-nav-links a{
  display:inline-block;
  padding:.2rem 0;
  font-size:.88rem;
  color:var(--mist);
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),transform var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.footer-nav-links a:hover,
.footer-nav-links a:focus-visible{
  color:var(--paper);
  transform:translateX(4px);
  border-bottom-color:var(--signal);
}

.footer-contact{display:flex;flex-direction:column}
.footer-contact-list{display:flex;flex-direction:column;gap:.45rem}
.footer-contact-list li{
  font-family:var(--font-mono);
  font-size:.82rem;
  letter-spacing:.03em;
  color:var(--paper);
  overflow-wrap:anywhere;
}
.footer-contact-label{
  display:inline-block;
  min-width:3.1em;
  margin-right:.55rem;
  font-family:var(--font-body);
  font-size:11px;
  letter-spacing:.14em;
  color:var(--mist);
}
.footer-note{
  margin-top:.85rem;
  font-size:.78rem;
  line-height:1.7;
  color:var(--mist);
}
.footer-copy{
  align-self:flex-start;
  margin-top:.85rem;
  padding:.45rem .8rem;
  border:1px solid var(--line);
  border-radius:4px;
  font-size:.78rem;
  letter-spacing:.08em;
  color:var(--teal-glow);
  transition:background var(--dur) var(--ease),border-color var(--dur) var(--ease),color var(--dur) var(--ease);
}
.footer-copy:hover,
.footer-copy:focus-visible{
  background:rgba(47,184,166,.16);
  border-color:var(--teal);
  color:var(--paper);
}
.footer-copy[data-copied]{
  background:var(--teal);
  border-color:var(--teal);
  color:var(--ink-900);
}

.footer-base{border-top:1px solid var(--line)}
.footer-base-inner{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:.7rem 1.6rem;
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding:1.05rem var(--edge) 1.5rem;
}
.footer-legal{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--mist);
}
.footer-legal-links{
  display:flex;
  flex-wrap:wrap;
  gap:1.1rem;
  font-size:.8rem;
}
.footer-legal-links a{
  color:var(--mist);
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.footer-legal-links a:hover,
.footer-legal-links a:focus-visible{
  color:var(--paper);
  border-bottom-color:var(--teal);
}

/* ===== responsive ===== */
@media (max-width:1079.98px){
  .site-nav{display:none}
  .site-nav[data-open]{
    display:flex;
    animation:nav-drop var(--dur) var(--ease);
  }
}

@keyframes nav-drop{
  from{opacity:0;transform:translateY(-8px)}
  to{opacity:1;transform:none}
}

@media (min-width:680px){
  .grid--2{grid-template-columns:repeat(2, minmax(0,1fr))}
}

@media (min-width:760px){
  .footer-inner{grid-template-columns:1.05fr 1.5fr 1.1fr;gap:2.2rem}
}

@media (min-width:860px){
  .grid--3{grid-template-columns:repeat(3, minmax(0,1fr))}
}

@media (min-width:1080px){
  html{scroll-padding-top:1.6rem}

  body{padding-left:var(--rail-w)}

  .site-header{
    position:fixed;
    inset:0 auto 0 0;
    width:var(--rail-w);
    border-bottom:0;
    border-right:1px solid var(--line);
    background:linear-gradient(180deg, #0D1A2C 0%, var(--ink-900) 48%, #0A1320 100%);
    box-shadow:none;
  }
  .site-header::after{
    left:0;
    bottom:0;
    width:2px;
    height:calc(var(--scroll-progress, 0) * 1%);
    max-height:100%;
    background:linear-gradient(180deg, var(--teal-glow), var(--signal) 78%);
    transition:height .08s linear;
  }

  .header-shell{
    height:100%;
    max-width:none;
    margin:0;
    padding:1.5rem 1.3rem 1.6rem;
    gap:1.15rem;
    overflow-y:auto;
    overscroll-behavior:contain;
  }

  .nav-toggle{display:none}

  .site-nav{
    flex:1;
    padding-top:0;
    border-top:0;
    gap:1.15rem;
  }

  .nav-util{margin-top:auto}

  .footer-inner{padding-top:3.1rem}
}

@media (min-width:1400px){
  :root{--rail-w:340px}
}

@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;
  }
  .site-header::after{transition:none}
}