/* ============ reset ============ */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:calc(var(--header-space) + 16px)}
body,h1,h2,h3,h4,h5,h6,p,figure,blockquote,ul,ol,dl,dd{margin:0}
ul,ol{padding:0;list-style:none}
img,svg,video{max-width:100%;height:auto}
button{font:inherit;color:inherit;background:none;border:0}
main{display:block}

/* ============ tokens ============ */
:root{
  --ink-900:#0B1B2B;
  --ink-700:#12304A;
  --paper:#F2E9DA;
  --gold:#C9913F;
  --gold-soft:#E5C48A;
  --teal:#7E959C;
  --brick:#A9503F;
  --cream:#F7F3EC;
  --charcoal:#22303A;
  --mist:#C9D6D9;

  --font-display:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --font-body:"Noto Sans SC","Source Han Sans SC","PingFang SC","Microsoft YaHei",system-ui,sans-serif;
  --font-mono:"IBM Plex Mono","JetBrains Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;

  --line:rgba(201,145,63,.28);
  --line-strong:rgba(201,145,63,.55);
  --line-ink:rgba(11,27,43,.16);
  --shell-max:1240px;
  --header-space:96px;
  --radius:14px;
  --ease:cubic-bezier(.2,.8,.2,1);
  --skew:6deg;
  --focus-ring:0 0 0 3px rgba(229,196,138,.8);
}

/* ============ base ============ */
body{
  padding-top:var(--header-space);
  background:var(--ink-900);
  color:var(--cream);
  font-family:var(--font-body);
  font-size:17px;
  font-weight:400;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
}
::selection{background:var(--gold);color:var(--ink-900)}
a{color:inherit;text-decoration-color:rgba(201,145,63,.6);text-underline-offset:.22em}
a:hover{text-decoration-color:var(--gold)}
:focus-visible{outline:3px solid var(--gold-soft);outline-offset:3px;border-radius:3px}
#main-content{scroll-margin-top:calc(var(--header-space) + 8px)}

/* ============ typography ============ */
h1,h2,h3,h4{
  font-family:var(--font-display);
  font-weight:800;
  line-height:1.16;
  letter-spacing:-.01em;
  color:inherit;
}
h1{font-size:clamp(34px,5.4vw,64px);margin-bottom:.42em}
h2{font-size:clamp(26px,3.4vw,48px);margin-bottom:.5em}
h3{font-size:clamp(20px,2.1vw,26px);margin-bottom:.55em}
h4{font-size:clamp(17px,1.6vw,20px);margin-bottom:.6em}
p{margin-bottom:1.05em}
p:last-child{margin-bottom:0}
strong{font-weight:700;color:var(--gold-soft)}
.section--paper strong,.card--paper strong{color:var(--brick)}

.k8-num{
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.08em;
  text-transform:uppercase;
  color:var(--gold);
}
.eyebrow{
  display:inline-flex;
  align-items:center;
  gap:10px;
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--gold);
}
.eyebrow::before{content:"";width:28px;height:2px;background:currentColor;border-radius:2px}

/* ============ layout ============ */
.container{
  width:100%;
  max-width:var(--shell-max);
  margin-inline:auto;
  padding-inline:clamp(16px,4vw,40px);
}
.section{padding-block:clamp(44px,6vw,84px)}
.section--ink{background:var(--ink-900);color:var(--cream)}
.section--paper{background:var(--paper);color:var(--charcoal)}
.section--paper .eyebrow,
.section--paper .k8-num{color:var(--brick)}
.section--paper .tag{color:var(--brick);border-color:rgba(169,80,63,.55)}
.prose{max-width:68ch;font-size:17px;line-height:1.78}
.prose p+p{margin-top:1.05em}

.grid{display:grid;gap:clamp(16px,2.4vw,28px)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--split{grid-template-columns:minmax(0,7fr) minmax(0,4fr)}

/* ============ buttons ============ */
.btn{
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:13px 22px;
  border:1px solid transparent;
  border-radius:999px;
  font-family:var(--font-body);
  font-size:15px;
  font-weight:700;
  line-height:1.2;
  text-decoration:none;
  cursor:pointer;
  transition:transform .18s var(--ease),background-color .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease);
}
.btn:hover{transform:translateY(-2px)}
.btn--gold{background:var(--gold);color:var(--ink-900);box-shadow:0 12px 26px -18px rgba(201,145,63,.9)}
.btn--gold:hover{background:var(--gold-soft)}
.btn--ghost{background:transparent;color:var(--cream);border-color:var(--line-strong)}
.btn--ghost:hover{border-color:var(--gold);color:var(--gold-soft)}
.btn--ink{background:var(--ink-900);color:var(--cream)}
.btn--ink:hover{background:var(--ink-700)}
.btn--sm{padding:9px 16px;font-size:13px}

/* ============ breadcrumbs ============ */
.breadcrumbs{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin-bottom:20px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.05em;
  color:var(--teal);
}
.breadcrumbs li{display:flex;align-items:center;gap:8px}
.breadcrumbs li+li::before{content:"/";color:var(--line-strong)}
.breadcrumbs a{color:inherit;text-decoration:none}
.breadcrumbs a:hover{color:var(--gold-soft)}
.breadcrumbs [aria-current="page"]{color:var(--cream)}

/* ============ cards / tags / decorations ============ */
.card{
  position:relative;
  background:var(--ink-700);
  color:var(--cream);
  border:1px solid var(--line);
  border-radius:var(--radius);
  padding:clamp(18px,2.4vw,26px);
}
.card--paper{
  background:var(--paper);
  color:var(--charcoal);
  border-color:var(--line-ink);
  box-shadow:0 18px 36px -30px rgba(0,0,0,.85);
}
.cut-corner{clip-path:polygon(0 0,calc(100% - 20px) 0,100% 20px,100% 100%,0 100%)}
.path-line{position:relative;padding-left:22px}
.path-line::before{
  content:"";
  position:absolute;
  left:0;top:6px;bottom:6px;
  width:2px;
  background:linear-gradient(180deg,var(--gold),rgba(201,145,63,0));
}
.slant-rule{
  display:block;
  width:64px;height:6px;
  background:var(--gold);
  border-radius:1px;
  transform:skewX(calc(var(--skew) * -1));
}
.tag{
  display:inline-flex;
  align-items:center;
  gap:6px;
  padding:3px 8px;
  border:1px solid currentColor;
  border-radius:2px;
  font-family:var(--font-mono);
  font-size:12px;
  font-weight:500;
  letter-spacing:.06em;
  line-height:1.4;
  text-transform:uppercase;
  color:var(--gold-soft);
}
.tag--ink{color:var(--brick);border-color:rgba(169,80,63,.55)}

/* ============ media frame ============ */
.media-frame{
  position:relative;
  display:block;
  overflow:hidden;
  border:1px solid var(--line);
  border-radius:var(--radius);
  background:linear-gradient(140deg,var(--ink-700),var(--ink-900));
}
.media-frame img{display:block;width:100%;height:100%;object-fit:cover}
.media-frame--ratio{aspect-ratio:16/10}
.media-frame::after{
  content:"";
  position:absolute;
  inset:0;
  pointer-events:none;
  background:repeating-linear-gradient(0deg,rgba(247,243,236,.05) 0 1px,transparent 1px 3px);
  opacity:.6;
}
.media-frame__label{
  position:absolute;
  left:14px;bottom:12px;
  z-index:1;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  text-transform:uppercase;
  color:var(--gold-soft);
}
.media-frame figcaption{
  padding:12px 16px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.04em;
  color:var(--teal);
}

/* ============ toc rail ============ */
.toc-rail{
  position:sticky;
  top:calc(var(--header-space) + 16px);
  align-self:start;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.05em;
}
.toc-title{
  margin-bottom:12px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--teal);
}
.toc-list{border-left:1px solid var(--line)}
.toc-link{
  display:block;
  margin-left:-1px;
  padding:7px 0 7px 14px;
  border-left:2px solid transparent;
  color:var(--teal);
  text-decoration:none;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.toc-link:hover{color:var(--cream)}
.toc-link[aria-current="true"]{color:var(--gold);border-left-color:var(--gold)}

/* ============ filter ============ */
.filter-bar{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  margin-bottom:22px;
}
.filter-btn{
  padding:8px 14px;
  border:1px solid var(--line-strong);
  border-radius:999px;
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.06em;
  color:var(--mist);
  cursor:pointer;
  transition:background-color .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease);
}
.filter-btn:hover{color:var(--cream);border-color:var(--gold)}
.filter-btn[aria-pressed="true"]{background:var(--gold);border-color:var(--gold);color:var(--ink-900);font-weight:700}
.filter-count{margin-left:auto;font-family:var(--font-mono);font-size:12px;color:var(--teal)}
.filter-item[hidden]{display:none !important}

/* ============ copy ============ */
.copy-btn{
  padding:5px 10px;
  border:1px solid var(--line);
  border-radius:999px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.08em;
  color:var(--gold-soft);
  cursor:pointer;
  transition:background-color .18s var(--ease),color .18s var(--ease),border-color .18s var(--ease);
}
.copy-btn:hover{background:rgba(201,145,63,.16);border-color:var(--gold)}
.copy-btn.is-copied{background:var(--gold);border-color:var(--gold);color:var(--ink-900)}
.copy-feedback{font-family:var(--font-mono);font-size:11px;letter-spacing:.04em;color:var(--gold-soft)}

/* ============ reveal ============ */
[data-reveal]{transition:opacity .6s var(--ease),transform .6s var(--ease)}
.has-js [data-reveal]{opacity:0;transform:translateY(12px)}
[data-reveal].is-revealed{opacity:1;transform:none}

/* ============ header ============ */
.site-header{
  position:fixed;
  inset:0 0 auto 0;
  z-index:100;
  padding:14px clamp(12px,3vw,28px) 0;
  pointer-events:none;
}
.skip-link{
  position:fixed;
  top:10px;left:10px;
  z-index:200;
  padding:12px 18px;
  border-radius:8px;
  background:var(--gold);
  color:var(--ink-900);
  font-family:var(--font-mono);
  font-size:13px;
  font-weight:700;
  letter-spacing:.04em;
  text-decoration:none;
  transform:translateY(-200%);
  transition:transform .2s var(--ease);
}
.skip-link:focus,.skip-link:focus-visible{transform:translateY(0);outline:3px solid var(--cream);outline-offset:2px}

.header-shell{
  position:relative;
  z-index:1;
  isolation:isolate;
  display:flex;
  align-items:center;
  gap:clamp(8px,1.6vw,24px);
  max-width:var(--shell-max);
  margin-inline:auto;
  padding:10px 12px 10px 14px;
  border:1px solid rgba(201,145,63,.34);
  border-radius:999px;
  pointer-events:auto;
  transition:padding .28s var(--ease),border-color .28s var(--ease);
}
.header-shell::before{
  content:"";
  position:absolute;
  inset:0;
  z-index:-1;
  border-radius:inherit;
  background:rgba(11,27,43,.86);
  -webkit-backdrop-filter:blur(14px) saturate(140%);
  backdrop-filter:blur(14px) saturate(140%);
  pointer-events:none;
}
.site-header.is-condensed .header-shell{padding:6px 10px 6px 12px;border-color:rgba(201,145,63,.55)}
.site-header.is-condensed .header-shell::before{background:rgba(9,22,35,.95)}

.brand-mark{
  flex:0 0 auto;
  display:inline-flex;
  align-items:center;
  gap:10px;
  padding:2px 6px 2px 2px;
  border-radius:999px;
  color:var(--cream);
  text-decoration:none;
}
.brand-seal{
  display:grid;
  place-items:center;
  width:34px;height:34px;
  border-radius:8px;
  background:var(--gold);
  color:var(--ink-900);
  font-family:var(--font-mono);
  font-size:13px;
  font-weight:700;
  letter-spacing:.04em;
  transform:rotate(-3deg);
  box-shadow:inset 0 0 0 2px rgba(11,27,43,.28);
}
.brand-text{display:flex;flex-direction:column;line-height:1.1}
.brand-name{font-family:var(--font-display);font-size:18px;font-weight:800;letter-spacing:-.01em}
.brand-note{font-family:var(--font-mono);font-size:10px;font-weight:500;letter-spacing:.1em;text-transform:uppercase;color:var(--teal)}

.site-nav{flex:1 1 auto;display:flex;justify-content:center;min-width:0}
.nav-list{display:flex;align-items:center;gap:2px}
.nav-item{display:block}
.nav-link{
  display:block;
  padding:8px 12px;
  border-radius:999px;
  font-size:14px;
  font-weight:500;
  line-height:1.3;
  color:var(--mist);
  text-decoration:none;
  white-space:nowrap;
  transition:color .18s var(--ease),background-color .18s var(--ease);
}
.nav-link:hover{color:var(--cream);background:rgba(201,145,63,.16)}
.nav-link[aria-current="page"]{background:var(--gold);color:var(--ink-900);font-weight:700}

.nav-toggle{
  display:none;
  align-items:center;
  gap:8px;
  padding:8px 12px;
  border:1px solid var(--line-strong);
  border-radius:999px;
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  color:var(--cream);
  cursor:pointer;
}
.nav-toggle-bars{display:inline-flex;flex-direction:column;gap:3px;width:16px}
.nav-toggle-bar{display:block;height:2px;border-radius:2px;background:var(--gold-soft);transition:transform .22s var(--ease)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1){transform:translateY(2.5px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2){transform:translateY(-2.5px) rotate(-45deg)}
.nav-toggle-text{text-transform:uppercase}

.header-cta{
  flex:0 0 auto;
  display:inline-flex;
  align-items:center;
  gap:8px;
  padding:10px 18px;
  border-radius:999px;
  background:linear-gradient(100deg,var(--gold),var(--gold-soft));
  color:var(--ink-900);
  font-size:14px;
  font-weight:700;
  line-height:1.2;
  text-decoration:none;
  white-space:nowrap;
  box-shadow:0 10px 22px -14px rgba(201,145,63,.95);
  transition:transform .18s var(--ease),filter .18s var(--ease);
}
.header-cta::after{content:"\2192";font-family:var(--font-mono);font-size:13px}
.header-cta:hover{transform:translateY(-1px);filter:brightness(1.06)}

.header-progress{
  max-width:var(--shell-max);
  margin:8px auto 0;
  height:2px;
  border-radius:2px;
  background:rgba(201,145,63,.16);
  overflow:hidden;
}
.header-progress span{
  display:block;
  height:100%;
  width:100%;
  transform:scaleX(0);
  transform-origin:0 50%;
  background:linear-gradient(90deg,var(--gold),var(--gold-soft));
}

body.nav-open{overflow:hidden}

/* ============ footer ============ */
.site-footer{
  position:relative;
  margin-top:clamp(48px,8vw,96px);
  padding:clamp(40px,6vw,72px) clamp(16px,4vw,40px) 26px;
  background:var(--ink-900);
  color:var(--cream);
  border-top:1px solid var(--line);
}
.site-footer::before{
  content:"";
  position:absolute;
  top:0;left:0;
  width:clamp(90px,18vw,220px);
  height:6px;
  background:var(--gold);
  transform:skewX(calc(var(--skew) * -1));
  transform-origin:left top;
}
.footer-inner{max-width:var(--shell-max);margin-inline:auto}
.footer-grid{
  display:grid;
  grid-template-columns:1.5fr repeat(3,minmax(0,1fr));
  gap:clamp(24px,4vw,48px);
  padding-bottom:clamp(24px,4vw,40px);
  border-bottom:1px solid rgba(201,145,63,.18);
}
.footer-brand{display:flex;flex-direction:column;gap:10px}
.footer-mark{
  display:inline-flex;
  align-items:center;
  gap:10px;
  color:var(--cream);
  text-decoration:none;
}
.footer-seal{
  display:grid;
  place-items:center;
  width:38px;height:38px;
  border-radius:8px;
  background:var(--gold);
  color:var(--ink-900);
  font-family:var(--font-mono);
  font-size:14px;
  font-weight:700;
  transform:rotate(-3deg);
}
.footer-name{font-family:var(--font-display);font-size:30px;font-weight:800;letter-spacing:-.01em}
.footer-note{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.12em;
  text-transform:uppercase;
  color:var(--teal);
}
.footer-line{max-width:26ch;font-size:14px;line-height:1.7;color:var(--mist)}
.footer-col{min-width:0}
.footer-title{
  display:flex;
  align-items:center;
  gap:8px;
  margin-bottom:14px;
  font-family:var(--font-mono);
  font-size:11px;
  font-weight:500;
  letter-spacing:.16em;
  text-transform:uppercase;
  color:var(--gold);
}
.footer-title::before{content:"";width:14px;height:2px;background:currentColor}
.footer-links{display:flex;flex-direction:column;gap:9px}
.footer-link{
  display:inline-block;
  font-size:14px;
  line-height:1.5;
  color:var(--mist);
  text-decoration:none;
  border-bottom:1px solid transparent;
  transition:color .18s var(--ease),border-color .18s var(--ease);
}
.footer-link:hover{color:var(--gold-soft);border-bottom-color:var(--gold-soft)}
.footer-contact{
  display:flex;
  flex-wrap:wrap;
  gap:10px clamp(20px,4vw,48px);
  padding-top:clamp(20px,3vw,30px);
}
.footer-contact-item{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  gap:8px;
  font-size:14px;
  line-height:1.6;
}
.footer-label{
  font-family:var(--font-mono);
  font-size:11px;
  letter-spacing:.1em;
  text-transform:uppercase;
  color:var(--teal);
}
.footer-value{font-family:var(--font-mono);font-size:13px;letter-spacing:.02em;color:var(--cream)}
.footer-contact-note{margin-top:12px;font-size:13px;line-height:1.7;color:var(--teal);max-width:70ch}
.footer-bottom{
  display:flex;
  flex-wrap:wrap;
  align-items:center;
  justify-content:space-between;
  gap:10px;
  margin-top:clamp(22px,3vw,32px);
  padding-top:18px;
  border-top:1px solid rgba(201,145,63,.18);
  font-family:var(--font-mono);
  font-size:12px;
  letter-spacing:.04em;
  color:var(--teal);
}
.footer-legal{color:var(--teal)}
.footer-copy{color:var(--mist)}

/* ============ responsive: tablet / mobile ============ */
@media (max-width:1023px){
  :root{--header-space:84px}
  .site-header{padding:10px 12px 0}
  .header-shell{padding:8px 10px 8px 12px;gap:8px}
  .header-progress{margin-top:6px}
  .brand-note{display:none}
  .brand-name{font-size:17px}
  .header-cta{padding:9px 14px;font-size:13px;order:2}
  .header-cta::after{display:none}
  .nav-toggle{display:inline-flex;order:3;margin-left:auto}
  .brand-mark{order:1}
  .site-nav{
    order:4;
    position:fixed;
    left:12px;right:12px;bottom:12px;
    display:block;
    padding:12px;
    border:1px solid rgba(201,145,63,.45);
    border-radius:22px;
    background:rgba(18,48,74,.97);
    box-shadow:0 26px 60px -22px rgba(0,0,0,.95);
    transform:translateY(140%);
    opacity:0;
    pointer-events:none;
    transition:transform .3s var(--ease),opacity .3s var(--ease);
  }
  .site-nav[data-open]{transform:translateY(0);opacity:1;pointer-events:auto}
  .nav-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px}
  .nav-link{
    padding:12px 14px;
    border-radius:10px;
    background:rgba(11,27,43,.6);
    font-size:14px;
  }
  .nav-link[aria-current="page"]{background:var(--gold);color:var(--ink-900)}

  .grid--split{grid-template-columns:minmax(0,1fr)}
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .toc-rail{position:static}

  .footer-grid{grid-template-columns:repeat(2,minmax(0,1fr))}
  .footer-brand{grid-column:1 / -1}
}

@media (max-width:639px){
  body{font-size:16px}
  .grid--2,.grid--3,.grid--split{grid-template-columns:minmax(0,1fr)}
  .nav-list{grid-template-columns:minmax(0,1fr)}
  .filter-count{margin-left:0;width:100%}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-name{font-size:26px}
  .footer-bottom{flex-direction:column;align-items:flex-start}
  .footer-contact{flex-direction:column;gap:8px}
}

/* ============ 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;
  }
  .has-js [data-reveal]{opacity:1;transform:none}
  .btn:hover,.header-cta:hover{transform:none}
  .site-nav{transition:none}
}