/* ===== 01. Reset ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{
  margin:0;
  min-height:100%;
  background-color:var(--paper);
  background-image:
    radial-gradient(circle at 10% 6%,rgba(200,162,74,.12),transparent 44%),
    radial-gradient(circle at 92% 2%,rgba(46,110,98,.08),transparent 40%),
    radial-gradient(circle at 50% 108%,rgba(58,46,36,.10),transparent 52%);
  background-attachment:fixed;
  color:var(--ink);
  font-family:var(--font-body);
  font-size:16px;
  line-height:1.75;
  -webkit-font-smoothing:antialiased;
}
img,svg,video{display:block;max-width:100%;height:auto}
button,input,select,textarea{font:inherit;color:inherit}
a{color:inherit}
h1,h2,h3,h4,h5{margin:0 0 .6em;font-family:var(--font-head);font-weight:600;line-height:1.3;letter-spacing:.01em}
h1{font-size:clamp(30px,4.4vw,48px)}
h2{font-size:clamp(24px,3vw,36px)}
h3{font-size:clamp(19px,2vw,22px)}
p{margin:0 0 1em}
p:last-child{margin-bottom:0}
ul,ol{padding-left:1.25em}

/* ===== 02. Tokens ===== */
:root{
  --ink:#141210;
  --paper:#F7F1E6;
  --gold:#C8A24A;
  --gold-soft:#E7D9B0;
  --cinnabar:#B33A2B;
  --jade:#2E6E62;
  --slate-blue:#5C6670;
  --paper-line:#E5DFD3;
  --brown:#3A2E24;
  --glass:rgba(255,255,255,.62);
  --card:#FFFDF8;
  --font-head:"Noto Serif SC","Source Han Serif SC","Songti SC","SimSun",serif;
  --font-body:"Noto Sans SC","PingFang SC","Hiragino Sans GB","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono","IBM Plex Mono",ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;
  --shell:1240px;
  --shell-narrow:760px;
  --radius:5px;
  --shadow-soft:0 1px 0 rgba(20,18,16,.05),0 12px 26px -22px rgba(20,18,16,.55);
  --shadow-lift:0 1px 0 rgba(20,18,16,.05),0 20px 34px -22px rgba(20,18,16,.42);
  --ease:160ms ease;
}
.mono,.num{font-family:var(--font-mono);font-variant-numeric:tabular-nums;letter-spacing:.08em}

/* ===== 03. Focus ===== */
:focus-visible{outline:2px solid var(--gold);outline-offset:3px;border-radius:2px}
.skip-link{
  position:absolute;top:-100px;left:1rem;z-index:200;
  padding:.6rem 1rem;background:var(--ink);color:var(--gold-soft);
  font-size:14px;text-decoration:none;border-radius:0 0 var(--radius) var(--radius);
  border:1px solid var(--gold);transition:top var(--ease);
}
.skip-link:focus{top:0}

/* ===== 04. Layout ===== */
.shell{width:min(var(--shell),100% - 2.5rem);margin-inline:auto}
.shell--narrow{width:min(var(--shell-narrow),100% - 2.5rem)}
.shell--wide{width:min(1480px,100% - 2rem)}
.band--ink{background:var(--ink);color:var(--paper)}
.band--brown{background:var(--brown);color:var(--paper)}
.band--glass{background:var(--glass);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);border-block:1px solid rgba(255,255,255,.7)}
.rule{height:1px;border:0;margin:0;background:var(--paper-line)}
.rule--gold{background:linear-gradient(90deg,var(--gold),rgba(200,162,74,0))}

/* ===== 05. Header ===== */
.masthead{position:sticky;top:0;z-index:60}
.masthead__slate{background:var(--ink);color:var(--gold-soft);border-bottom:1px solid rgba(200,162,74,.34)}
.masthead__slate-inner{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;
  gap:.4rem 1.5rem;min-height:38px;padding-block:.35rem;font-size:12.5px;
}
.masthead__record{display:flex;flex-wrap:wrap;align-items:center;gap:.7rem;margin:0}
.masthead__record-no{
  font-size:11px;letter-spacing:.2em;color:var(--ink);background:var(--gold);
  padding:.14rem .45rem;border-radius:2px;
}
.masthead__tagline{color:rgba(231,217,176,.86);letter-spacing:.05em}
.masthead__meta{display:flex;flex-wrap:wrap;align-items:center;gap:1.1rem;margin:0}
.masthead__hint{color:rgba(231,217,176,.62)}
.ghost-link{
  display:inline-flex;align-items:center;gap:.4rem;color:inherit;text-decoration:none;
  font-size:13px;letter-spacing:.03em;padding-bottom:1px;opacity:.88;
  border-bottom:1px solid currentColor;transition:color var(--ease),opacity var(--ease);
}
.ghost-link::after{content:"→";font-family:var(--font-mono);transition:transform var(--ease)}
.ghost-link:hover,.ghost-link:focus-visible{color:var(--gold);opacity:1}
.ghost-link:hover::after{transform:translateX(3px)}

.masthead__bar{
  background:rgba(247,241,230,.9);
  backdrop-filter:blur(10px);-webkit-backdrop-filter:blur(10px);
  border-bottom:1px solid var(--paper-line);
  transition:box-shadow var(--ease);
}
.masthead__bar-inner{display:flex;align-items:center;justify-content:space-between;gap:1.5rem;min-height:76px;transition:min-height var(--ease)}
.masthead[data-scrolled] .masthead__bar-inner{min-height:62px}
.masthead[data-scrolled]{box-shadow:0 14px 30px -26px rgba(20,18,16,.8)}

.brand{display:inline-flex;align-items:center;gap:.75rem;text-decoration:none;color:var(--ink)}
.brand__seal{
  display:grid;place-items:center;width:42px;height:42px;flex:none;
  background:var(--ink);color:var(--gold);font-family:var(--font-head);font-size:20px;
  border-radius:4px;box-shadow:inset 0 0 0 1px rgba(200,162,74,.6),0 2px 0 var(--brown);
}
.brand__text{display:grid;gap:1px}
.brand__name{font-family:var(--font-head);font-size:20px;letter-spacing:.08em;line-height:1.2}
.brand__sub{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.16em;color:var(--slate-blue)}

.nav{display:flex;align-items:center}
.nav__list{display:flex;align-items:center;gap:.15rem;margin:0;padding:0;list-style:none}
.nav__item{list-style:none}
.nav__link{
  position:relative;display:inline-flex;align-items:baseline;gap:.42rem;
  padding:.6rem .7rem;color:var(--ink);text-decoration:none;font-size:15px;letter-spacing:.02em;
  transition:color var(--ease);
}
.nav__link::after{
  content:"";position:absolute;left:.7rem;right:.7rem;bottom:.32rem;height:2px;
  background:var(--gold);transform:scaleX(0);transform-origin:left center;
  transition:transform var(--ease);
}
.nav__link:hover,.nav__link:focus-visible{color:var(--brown)}
.nav__link:hover::after,.nav__link:focus-visible::after{transform:scaleX(1)}
.nav__link[aria-current="page"]{color:var(--ink);font-weight:600}
.nav__link[aria-current="page"]::after{transform:scaleX(1)}
.nav__link[aria-current="page"] .nav__index{color:var(--cinnabar)}
.nav__index{font-family:var(--font-mono);font-size:10.5px;letter-spacing:.16em;color:var(--gold)}
.nav__extra{display:none}

.nav-toggle{
  display:none;position:relative;z-index:75;align-items:center;gap:.6rem;
  padding:.5rem .75rem;background:transparent;border:1px solid var(--paper-line);
  border-radius:var(--radius);color:var(--ink);cursor:pointer;transition:border-color var(--ease),background-color var(--ease);
}
.nav-toggle:hover{border-color:var(--gold);background:rgba(200,162,74,.1)}
.nav-toggle__icon{display:grid;gap:4px;width:18px}
.nav-toggle__bar{display:block;height:2px;background:currentColor;transition:transform var(--ease),opacity var(--ease)}
.nav-toggle__label{font-size:13px;letter-spacing:.1em}
.masthead[data-open] .nav-toggle__bar:nth-child(1){transform:translateY(6px) rotate(45deg)}
.masthead[data-open] .nav-toggle__bar:nth-child(2){opacity:0}
.masthead[data-open] .nav-toggle__bar:nth-child(3){transform:translateY(-6px) rotate(-45deg)}

.masthead__progress{position:absolute;left:0;right:0;bottom:-1px;height:2px;overflow:hidden}
.progress__bar{
  display:block;height:100%;width:100%;transform:scaleX(0);transform-origin:left center;
  background:linear-gradient(90deg,var(--gold),var(--cinnabar));
}
body.nav-locked{overflow:hidden}

/* ===== 06. Footer ===== */
.site-foot{
  margin-top:clamp(3rem,7vw,6rem);
  background:var(--ink);color:var(--gold-soft);
  border-top:3px solid var(--gold);
}
.foot__top{
  display:grid;grid-template-columns:1.4fr 1fr 1.5fr;
  gap:clamp(1.5rem,4vw,3.25rem);
  padding:clamp(2.4rem,5vw,3.8rem) 0 clamp(1.6rem,4vw,2.4rem);
}
.foot__brand{display:block}
.foot__seal{
  display:grid;place-items:center;width:46px;height:46px;
  background:var(--brown);color:var(--gold);font-family:var(--font-head);font-size:22px;
  border-radius:4px;box-shadow:inset 0 0 0 1px rgba(200,162,74,.55);
}
.foot__name{font-family:var(--font-head);font-size:23px;letter-spacing:.08em;color:#FBF6EC;margin:.8rem 0 .35rem}
.foot__desc{margin:0;max-width:34ch;font-size:14px;line-height:1.8;color:rgba(247,241,230,.7)}
.foot__col{min-width:0}
.foot__title{
  margin:0 0 1rem;font-family:var(--font-mono);font-size:11.5px;font-weight:500;
  letter-spacing:.24em;color:var(--gold);text-transform:none;
}
.foot__links{list-style:none;margin:0;padding:0;display:grid;gap:.6rem}
.foot__link{
  display:inline-block;color:rgba(247,241,230,.82);text-decoration:none;font-size:14.5px;
  padding-bottom:2px;background-image:linear-gradient(var(--gold),var(--gold));
  background-repeat:no-repeat;background-position:0 100%;background-size:0 1px;
  transition:background-size var(--ease),color var(--ease);
}
.foot__link:hover,.foot__link:focus-visible{color:#FBF6EC;background-size:100% 1px}
.foot__contact{list-style:none;margin:0;padding:0;display:grid;gap:.85rem}
.foot__label{display:block;font-family:var(--font-mono);font-size:10.5px;letter-spacing:.2em;color:var(--gold);margin-bottom:.2rem}
.foot__value{display:block;font-size:14px;color:rgba(247,241,230,.88);word-break:break-word}
.foot__note{margin:1.1rem 0 0;font-size:12.5px;line-height:1.75;color:rgba(247,241,230,.55);max-width:46ch}
.foot__bar{
  display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:.5rem 1.5rem;
  padding:1.1rem 0 1.8rem;border-top:1px solid rgba(231,217,176,.2);
  font-size:12.5px;color:rgba(247,241,230,.6);
}
.foot__legal{margin:0}
.foot__copy{margin:0}

/* ===== 07. Section & chapter ===== */
.section{padding:clamp(2.4rem,6vw,4.6rem) 0}
.section__head{
  display:grid;grid-template-columns:auto minmax(0,1fr);align-items:baseline;
  gap:.35rem 1.25rem;padding-bottom:1rem;margin-bottom:clamp(1.2rem,3vw,2rem);
  border-bottom:1px solid var(--paper-line);
}
.section__num{
  font-family:var(--font-mono);font-size:clamp(28px,4vw,44px);line-height:1;
  letter-spacing:-.02em;color:var(--gold);
}
.section__title{margin:0;font-size:clamp(23px,3vw,34px);letter-spacing:.02em}
.section__lead{grid-column:2;margin:0;max-width:62ch;font-size:14.5px;color:var(--slate-blue)}
.eyebrow{
  display:inline-flex;align-items:center;gap:.55rem;font-family:var(--font-mono);
  font-size:11px;letter-spacing:.22em;color:var(--jade);margin-bottom:.7rem;
}
.eyebrow::before{content:"";width:26px;height:1px;background:var(--jade)}

/* ===== 08. Grid ===== */
.grid{display:grid;gap:clamp(1rem,2.4vw,1.75rem)}
.grid--2{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid--3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid--rail{grid-template-columns:minmax(0,3fr) minmax(0,8fr);gap:clamp(1.25rem,4vw,3.5rem)}
.stacker>*:nth-child(even){transform:translateY(10px)}

/* ===== 09. Card & plate & tag ===== */
.card{
  position:relative;background:var(--card);border:1px solid var(--paper-line);border-radius:var(--radius);
  padding:clamp(1.05rem,2.4vw,1.6rem);box-shadow:var(--shadow-soft);
  transition:transform var(--ease),box-shadow var(--ease),border-color var(--ease);
}
.card:hover{transform:translateY(-3px);border-color:var(--gold);box-shadow:var(--shadow-lift)}
.card--glass{
  background:var(--glass);backdrop-filter:blur(8px);-webkit-backdrop-filter:blur(8px);
  border-color:rgba(255,255,255,.75);
}
.card--ink{background:var(--brown);color:var(--paper);border-color:transparent}
.card--ink .card__text,.card--ink .card__meta{color:rgba(247,241,230,.75)}
.card__label{font-family:var(--font-mono);font-size:11px;letter-spacing:.2em;color:var(--gold);margin:0 0 .45rem}
.card__title{margin:0 0 .5rem;font-size:19px}
.card__text{margin:0;font-size:14.5px;color:#3D3833}
.card__meta{margin:.85rem 0 0;font-family:var(--font-mono);font-size:11.5px;letter-spacing:.12em;color:var(--slate-blue)}

.plate{
  display:grid;gap:.22rem;padding:.75rem .95rem;background:var(--card);
  border:1px solid var(--paper-line);border-left:3px solid var(--gold);border-radius:3px;
}
.plate__label{margin:0;font-family:var(--font-mono);font-size:10.5px;letter-spacing:.16em;color:var(--slate-blue)}
.plate__value{margin:0;font-size:15px;color:var(--ink)}
.plate--red{border-left-color:var(--cinnabar)}
.plate--red .plate__label{color:var(--cinnabar)}
.plate--jade{border-left-color:var(--jade)}
.plate--jade .plate__label{color:var(--jade)}

.tag{
  display:inline-flex;align-items:center;gap:.35rem;padding:.2rem .55rem;border-radius:3px;
  font-family:var(--font-mono);font-size:11px;letter-spacing:.12em;
  background:var(--gold-soft);color:var(--brown);border:1px solid rgba(200,162,74,.5);
}
.tag--gold{background:var(--gold);color:#1B1712;border-color:var(--gold)}
.tag--jade{background:rgba(46,110,98,.12);color:var(--jade);border-color:rgba(46,110,98,.42)}
.tag--red{background:rgba(179,58,43,.12);color:var(--cinnabar);border-color:rgba(179,58,43,.42)}
.tag--ink{background:var(--ink);color:var(--gold-soft);border-color:var(--ink)}

/* ===== 10. Buttons ===== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  padding:.72rem 1.15rem;border:1px solid transparent;border-radius:var(--radius);
  font-family:var(--font-body);font-size:14.5px;letter-spacing:.04em;text-decoration:none;
  cursor:pointer;transition:background-color var(--ease),color var(--ease),border-color var(--ease),transform var(--ease);
}
.btn--ink{background:var(--ink);color:var(--paper)}
.btn--ink:hover,.btn--ink:focus-visible{background:var(--brown);transform:translateY(-1px)}
.btn--gold{background:var(--gold);color:#1B1712}
.btn--gold:hover,.btn--gold:focus-visible{background:#D8B65E;transform:translateY(-1px)}
.btn--outline{background:transparent;border-color:var(--ink);color:var(--ink)}
.btn--outline:hover,.btn--outline:focus-visible{background:var(--ink);color:var(--paper)}
.btn--jade{background:var(--jade);color:#F3FBF8}
.btn--jade:hover,.btn--jade:focus-visible{background:#255C52}

/* ===== 11. Crumbs & prose ===== */
.crumbs{font-size:12.5px;color:var(--slate-blue)}
.crumbs__list{
  display:flex;flex-wrap:wrap;align-items:center;gap:.45rem;list-style:none;margin:0;padding:0;
  font-family:var(--font-mono);letter-spacing:.08em;
}
.crumbs__list li+li::before{content:"/";margin-right:.45rem;color:var(--paper-line)}
.crumbs__link{color:var(--slate-blue);text-decoration:none;transition:color var(--ease)}
.crumbs__link:hover,.crumbs__link:focus-visible{color:var(--cinnabar)}
.crumbs__current{color:var(--ink)}
.prose{max-width:68ch;font-size:15.5px;line-height:1.9;color:#332E29}
.prose h2,.prose h3{margin-top:1.8em}
.prose a{color:var(--brown);text-decoration:none;border-bottom:1px solid var(--gold)}
.prose a:hover{color:var(--cinnabar)}
.prose blockquote{
  margin:1.4em 0;padding:.4em 0 .4em 1.1em;border-left:3px solid var(--gold);
  font-family:var(--font-head);color:var(--brown);
}
.prose code{font-family:var(--font-mono);font-size:.9em;background:var(--paper-line);padding:.1em .35em;border-radius:2px}

/* ===== 12. Media ===== */
.media{
  position:relative;display:block;overflow:hidden;border:1px solid var(--paper-line);
  border-radius:var(--radius);background:var(--paper-line);aspect-ratio:var(--media-ratio,16/9);
}
.media>img,.media>svg,.media>video{width:100%;height:100%;object-fit:cover}
.media::after{
  content:"";position:absolute;inset:0;pointer-events:none;
  background-image:radial-gradient(rgba(20,18,16,.16) 1px,transparent 1.1px);
  background-size:5px 5px;opacity:.42;mix-blend-mode:multiply;
}
.media--wide{--media-ratio:21/9}
.media--card{--media-ratio:4/3}
.media--square{--media-ratio:1/1}
.media--tall{--media-ratio:3/4}
.media__cap{
  position:absolute;left:.6rem;bottom:.6rem;z-index:1;max-width:calc(100% - 1.2rem);
  padding:.28rem .6rem;border-radius:3px;background:var(--glass);
  backdrop-filter:blur(6px);-webkit-backdrop-filter:blur(6px);
  font-family:var(--font-mono);font-size:11px;letter-spacing:.14em;color:var(--brown);
  border:1px solid rgba(255,255,255,.7);
}

/* ===== 13. Fold ===== */
.fold{border:1px solid var(--paper-line);border-radius:var(--radius);background:var(--card);overflow:hidden}
.fold+.fold{margin-top:.6rem}
.fold__summary{
  display:flex;align-items:center;gap:.75rem;padding:.9rem 1.1rem;cursor:pointer;
  font-family:var(--font-head);font-size:16.5px;list-style:none;
}
.fold__summary::-webkit-details-marker{display:none}
.fold__summary::after{
  content:"+";margin-left:auto;font-family:var(--font-mono);font-size:18px;color:var(--gold);
}
.fold[open] .fold__summary::after{content:"–"}
.fold__body{padding:0 1.1rem 1.15rem;font-size:14.8px;color:#3D3833}
.fold[open] .fold__body{animation:fold-in var(--ease) both}
@keyframes fold-in{from{opacity:0;transform:translateY(-3px)}to{opacity:1;transform:none}}

/* ===== 14. To top ===== */
.to-top{
  position:fixed;right:clamp(.8rem,3vw,1.6rem);bottom:clamp(.8rem,3vw,1.6rem);z-index:50;
  display:grid;place-items:center;width:44px;height:44px;border-radius:50%;
  background:var(--ink);color:var(--gold);border:1px solid rgba(200,162,74,.5);
  cursor:pointer;opacity:0;visibility:hidden;transform:translateY(8px);
  transition:opacity var(--ease),transform var(--ease),visibility var(--ease),background-color var(--ease);
}
.to-top[data-visible]{opacity:1;visibility:visible;transform:none}
.to-top:hover{background:var(--brown)}

/* ===== 15. Responsive ===== */
@media (max-width:1080px){
  .grid--3{grid-template-columns:repeat(2,minmax(0,1fr))}
  .grid--rail{grid-template-columns:minmax(0,1fr)}
}
@media (max-width:960px){
  .nav-toggle{display:inline-flex}
  .nav{
    position:fixed;top:0;right:0;z-index:70;
    width:min(88vw,360px);height:100dvh;max-height:100dvh;
    flex-direction:column;align-items:stretch;
    padding:5.5rem 1.4rem 2rem;overflow-y:auto;
    background:var(--ink);border-left:1px solid rgba(200,162,74,.42);
    transform:translateX(102%);visibility:hidden;
    transition:transform .22s ease,visibility .22s ease;
  }
  .masthead[data-open] .nav{transform:translateX(0);visibility:visible}
  .masthead[data-open]::after{
    content:"";position:fixed;inset:0;z-index:65;background:rgba(20,18,16,.55);
  }
  .nav__list{flex-direction:column;align-items:stretch;gap:0}
  .nav__item{border-bottom:1px solid rgba(231,217,176,.16)}
  .nav__link{display:flex;color:var(--paper);font-size:17px;padding:.95rem .2rem}
  .nav__link::after{display:none}
  .nav__link:hover,.nav__link:focus-visible{color:var(--gold)}
  .nav__link[aria-current="page"]{color:var(--gold)}
  .nav__index{color:rgba(200,162,74,.75)}
  .nav__extra{display:grid;gap:.9rem;margin-top:1.6rem}
  .nav__extra .ghost-link{color:rgba(231,217,176,.75);font-size:13.5px;width:max-content}
  .masthead__hint{display:none}
}
@media (max-width:900px){
  .foot__top{grid-template-columns:minmax(0,1fr)}
  .foot__col--contact{padding-top:.4rem}
}
@media (max-width:760px){
  body{font-size:15px}
  .shell{width:calc(100% - 1.8rem)}
  .grid--2,.grid--3{grid-template-columns:minmax(0,1fr)}
  .stacker>*:nth-child(even){transform:none}
  .masthead__slate-inner{justify-content:flex-start;font-size:12px}
  .brand__seal{width:38px;height:38px;font-size:18px}
  .brand__name{font-size:18px}
  .brand__sub{font-size:10px;letter-spacing:.12em}
  .section__head{grid-template-columns:minmax(0,1fr)}
  .section__lead{grid-column:1}
  .foot__bar{flex-direction:column;align-items:flex-start}
}

/* ===== 16. Reduced motion ===== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.001ms !important;
    animation-iteration-count:1 !important;
    transition-duration:.001ms !important;
  }
  .card:hover,.btn:hover{transform:none}
  .nav{transition:none}
}