/* ===== 01 reset ===== */
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth}
body{margin:0}
h1,h2,h3,h4,h5,p,figure,blockquote,dl,dd{margin:0}
ul,ol{margin:0;padding:0;list-style:none}
button{font:inherit;color:inherit;background:none;border:0;padding:0;cursor:pointer}
a{color:inherit;text-decoration:none}
img,svg,video{display:block;max-width:100%;height:auto}
[hidden]{display:none!important}

/* ===== 02 tokens ===== */
:root{
  --ink-900:#0B2A45;
  --ink-700:#123E63;
  --ink-500:#1F5C8B;
  --amber-500:#E0A33E;
  --amber-300:#F2C879;
  --coral-500:#E4694B;
  --sage-500:#7E9A8C;
  --sage-100:#E6ECE8;
  --stone-200:#D9DEE2;
  --stone-100:#EDF0F2;
  --paper:#F7F4EC;
  --paper-2:#FFFDF7;
  --graphite:#26303A;
  --graphite-soft:#56636F;

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

  --fs-xs:.75rem;
  --fs-sm:.8125rem;
  --fs-base:1rem;
  --fs-md:1.0625rem;
  --fs-lg:1.25rem;
  --fs-xl:1.625rem;
  --fs-2xl:2.125rem;
  --fs-3xl:3rem;
  --fs-display:clamp(2.4rem,5.4vw,4.6rem);

  --shell:1240px;
  --gutter:clamp(1.125rem,4vw,3rem);
  --radius-s:6px;
  --radius-m:14px;
  --radius-pill:999px;
  --line:1px solid var(--stone-200);
  --shadow-sheet:0 1px 0 rgba(11,42,69,.05),0 18px 40px -30px rgba(11,42,69,.5);
  --shadow-float:0 26px 52px -32px rgba(11,42,69,.7);
  --ease:cubic-bezier(.22,.61,.36,1);
  --dur:300ms;
}

/* ===== 03 base typography ===== */
body{
  background:var(--paper);
  color:var(--graphite);
  font-family:var(--font-body);
  font-size:var(--fs-base);
  line-height:1.78;
  -webkit-font-smoothing:antialiased;
}
h1,h2,h3,h4{font-family:var(--font-display);color:var(--ink-900);line-height:1.1;letter-spacing:-.01em;font-weight:800}
h1{font-size:var(--fs-display);line-height:1.06}
h2{font-size:clamp(1.5rem,3vw,var(--fs-2xl))}
h3{font-size:var(--fs-lg)}
strong{font-weight:700;color:var(--ink-900)}
::selection{background:var(--amber-300);color:var(--ink-900)}
:focus-visible{outline:2px solid var(--amber-500);outline-offset:3px;border-radius:3px}

/* ===== 04 utilities ===== */
.page-shell{width:min(var(--shell),100% - var(--gutter)*2);margin-inline:auto}
.page-main{display:block;padding-block:clamp(1.75rem,4vw,3rem) clamp(3rem,7vw,6rem)}
.visually-hidden{position:absolute!important;width:1px;height:1px;margin:-1px;padding:0;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}
.mono{font-family:var(--font-mono);font-size:var(--fs-sm);letter-spacing:.08em}
.kicker{display:inline-block;font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.16em;text-transform:uppercase;color:var(--ink-500)}
.rule{position:relative;height:1px;border:0;margin:0;background:var(--stone-200)}
.rule::before{content:"";position:absolute;left:0;top:-1px;width:36px;height:3px;background:var(--amber-500)}

/* ===== 05 skip link ===== */
.skip-link{
  position:fixed;left:.75rem;top:.75rem;z-index:200;
  transform:translateY(-180%);
  background:var(--ink-900);color:var(--paper-2);
  padding:.7rem 1.05rem;border-radius:var(--radius-s);
  font-size:.875rem;font-weight:700;
  transition:transform 200ms var(--ease);
}
.skip-link:focus{transform:translateY(0)}

/* ===== 06 header shell ===== */
.site-header{
  position:sticky;top:0;z-index:80;
  padding:clamp(.55rem,1.2vw,.9rem) 0 .3rem;
}
.header-shell{
  position:relative;
  width:min(var(--shell),100% - var(--gutter)*2);
  margin-inline:auto;
  display:flex;align-items:center;gap:clamp(.6rem,1.6vw,1.5rem);
  padding:.45rem .5rem .45rem 1rem;
  background:rgba(255,253,247,.94);
  border:1px solid rgba(217,222,226,.95);
  border-radius:var(--radius-pill);
  box-shadow:var(--shadow-sheet);
  -webkit-backdrop-filter:blur(10px);
  backdrop-filter:blur(10px);
  transition:padding var(--dur) var(--ease),box-shadow var(--dur) var(--ease),border-radius var(--dur) var(--ease);
}
.site-header[data-scrolled="true"] .header-shell{
  padding-block:.24rem;
  border-radius:18px;
  box-shadow:var(--shadow-float);
}

/* brand */
.brand{display:flex;align-items:center;gap:.7rem;flex:none;min-width:0}
.brand-mark{position:relative;display:block;width:26px;height:26px;flex:none}
.brand-mark__sheet{position:absolute;width:20px;height:20px;border-radius:3px;border:1px solid var(--stone-200);background:var(--paper-2)}
.brand-mark__sheet:nth-child(1){left:0;top:0;background:var(--ink-900);border-color:var(--ink-900)}
.brand-mark__sheet:nth-child(2){left:3px;top:3px;background:var(--amber-500);border-color:var(--amber-500)}
.brand-mark__sheet:nth-child(3){left:6px;top:6px;background:var(--paper-2);border-color:var(--ink-500)}
.brand-name{display:block;font-family:var(--font-display);font-size:1.0625rem;font-weight:900;letter-spacing:.03em;color:var(--ink-900);line-height:1.15}
.brand-note{display:block;font-family:var(--font-mono);font-size:.625rem;letter-spacing:.09em;color:var(--graphite-soft);line-height:1.3;white-space:nowrap}

/* ===== 07 navigation ===== */
.site-nav{display:flex;align-items:center;gap:.1rem;margin-left:auto;min-width:0}
.site-nav__list{display:flex;align-items:center;gap:.1rem}
.site-nav__link{
  display:inline-block;padding:.5rem .68rem;
  border-radius:var(--radius-pill);
  font-size:.9375rem;font-weight:500;color:var(--graphite);
  white-space:nowrap;
  transition:background var(--dur) var(--ease),color var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.site-nav__link:hover{background:var(--stone-100);color:var(--ink-900)}
.site-nav__link[aria-current="page"]{
  background:rgba(224,163,62,.16);
  color:var(--ink-900);
  font-weight:800;
  box-shadow:inset 0 -2px 0 var(--amber-500);
}
.site-nav__tools{
  display:flex;align-items:center;gap:.5rem;
  margin-left:.45rem;padding-left:.7rem;
  border-left:1px solid var(--stone-200);
}

/* ===== 08 version switch ===== */
.version-switch{position:relative}
.version-switch__trigger{
  display:flex;align-items:center;gap:.45rem;
  padding:.42rem .6rem .42rem .72rem;
  background:var(--paper-2);
  border:1px solid var(--stone-200);
  border-radius:var(--radius-pill);
  font-size:.8125rem;color:var(--ink-700);
  transition:border-color var(--dur) var(--ease),background var(--dur) var(--ease);
}
.version-switch__trigger:hover{border-color:var(--amber-500);background:#fff}
.version-switch__label{font-family:var(--font-mono);font-size:.625rem;letter-spacing:.12em;text-transform:uppercase;color:var(--graphite-soft)}
.version-switch__current{font-weight:800;color:var(--ink-900);white-space:nowrap}
.version-switch__chev{width:.42rem;height:.42rem;border-right:1.5px solid currentColor;border-bottom:1.5px solid currentColor;transform:rotate(45deg) translateY(-1px);transition:transform var(--dur) var(--ease)}
.version-switch__trigger[aria-expanded="true"] .version-switch__chev{transform:rotate(225deg) translateY(-1px)}
.version-switch__menu{
  position:absolute;right:0;top:calc(100% + .65rem);z-index:90;
  width:17.5rem;display:grid;gap:.4rem;
  padding:.85rem;
  background:var(--ink-900);
  border:1px solid var(--ink-700);
  border-radius:var(--radius-m);
  box-shadow:var(--shadow-float);
}
.version-switch__hint{
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.14em;text-transform:uppercase;
  color:rgba(247,244,236,.62);padding:.1rem .25rem .35rem;
  border-bottom:1px solid rgba(247,244,236,.14);margin-bottom:.15rem;
}
.version-card{
  display:grid;
  grid-template-columns:auto 1fr;
  grid-template-areas:"code name" "code note";
  gap:.12rem .6rem;
  width:100%;text-align:left;
  padding:.6rem .65rem;
  border-radius:10px;
  border:1px solid transparent;
  background:rgba(247,244,236,.06);
  color:var(--paper);
  transition:transform var(--dur) var(--ease),background var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.version-card:hover,.version-card:focus-visible{background:rgba(247,244,236,.13);border-color:var(--amber-300);transform:translateY(-2px)}
.version-card[aria-pressed="true"]{background:rgba(224,163,62,.2);border-color:var(--amber-500)}
.version-card__code{
  grid-area:code;align-self:center;
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.08em;
  color:var(--amber-300);
  border:1px solid rgba(242,200,121,.5);border-radius:4px;
  padding:.1rem .3rem;
}
.version-card__name{grid-area:name;font-size:.9375rem;font-weight:800;line-height:1.4}
.version-card__note{grid-area:note;font-size:.75rem;line-height:1.5;color:rgba(247,244,236,.72)}

/* ===== 09 buttons ===== */
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:.5rem;
  padding:.85rem 1.35rem;
  border:1px solid transparent;border-radius:var(--radius-pill);
  font-family:var(--font-body);font-size:.9375rem;font-weight:800;line-height:1;
  text-align:center;cursor:pointer;
  transition:background var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease),transform var(--dur) var(--ease),box-shadow var(--dur) var(--ease);
}
.btn:hover{transform:translateY(-1px)}
.btn--primary{background:var(--amber-500);color:var(--ink-900);box-shadow:0 10px 22px -16px rgba(224,163,62,.9)}
.btn--primary:hover{background:var(--amber-300)}
.btn--ghost{background:var(--paper-2);border-color:var(--stone-200);color:var(--ink-700)}
.btn--ghost:hover{border-color:var(--ink-500);color:var(--ink-900)}
.btn--ink{background:var(--ink-900);color:var(--paper-2)}
.btn--ink:hover{background:var(--ink-700)}
.btn--sm{padding:.6rem 1rem;font-size:.8125rem}
.header-cta{padding:.66rem 1.05rem;font-size:.875rem;white-space:nowrap}

/* ===== 10 nav toggle ===== */
.nav-toggle{
  display:none;align-items:center;gap:.45rem;margin-left:auto;
  padding:.5rem .72rem;
  background:var(--paper-2);border:1px solid var(--stone-200);border-radius:var(--radius-pill);
  color:var(--ink-900);font-size:.8125rem;font-weight:800;
  transition:border-color var(--dur) var(--ease);
}
.nav-toggle:hover{border-color:var(--amber-500)}
.nav-toggle__bars{display:grid;gap:4px;width:16px}
.nav-toggle__bars span{display:block;height:2px;border-radius:2px;background:currentColor;transition:transform var(--dur) var(--ease),opacity var(--dur) var(--ease)}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1){transform:translateY(6px) 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(-6px) rotate(-45deg)}
.nav-toggle__label{line-height:1}

/* ===== 11 header progress ===== */
.header-progress{
  width:min(var(--shell),100% - var(--gutter)*2);
  margin:.35rem auto 0;height:2px;border-radius:2px;
  background:rgba(217,222,226,.7);
  overflow:hidden;
}
.header-progress__bar{
  display:block;height:100%;width:100%;
  transform:scaleX(0);transform-origin:left center;
  background:linear-gradient(90deg,var(--amber-500),var(--coral-500));
  transition:transform 120ms linear;
}

/* ===== 12 footer ===== */
.site-footer{
  position:relative;overflow:hidden;
  background:var(--paper);
  border-top:1px solid var(--stone-200);
  padding-block:clamp(2.5rem,6vw,4.5rem) clamp(1.1rem,2.5vw,1.75rem);
}
.footer-shell{position:relative;z-index:1;width:min(var(--shell),100% - var(--gutter)*2);margin-inline:auto}
.footer-grid{display:grid;grid-template-columns:minmax(0,1.15fr) minmax(0,1.65fr) minmax(0,1.05fr);gap:clamp(1.6rem,4vw,3rem)}
.footer-wordmark{font-family:var(--font-display);font-size:1.75rem;font-weight:900;letter-spacing:.04em;color:var(--ink-900);line-height:1.1}
.footer-brand__line{
  display:inline-block;margin-top:.45rem;
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.16em;text-transform:uppercase;
  color:var(--ink-700);
  box-shadow:inset 0 -2px 0 var(--amber-500);
  padding-bottom:.2rem;
}
.footer-brand__note{margin-top:.9rem;font-size:.875rem;line-height:1.75;color:var(--graphite-soft);max-width:26em}
.footer-legal{display:flex;flex-wrap:wrap;gap:.35rem 1rem;margin-top:1.1rem;padding-top:.85rem;border-top:1px solid var(--stone-200)}
.footer-legal__link{font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.08em;color:var(--graphite-soft);transition:color var(--dur) var(--ease)}
.footer-legal__link:hover{color:var(--ink-500)}
.footer-nav{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:1.5rem}
.footer-col__title{
  font-family:var(--font-body);font-size:.9375rem;font-weight:800;color:var(--ink-900);
  padding-bottom:.55rem;margin-bottom:.7rem;
  border-bottom:1px solid var(--stone-200);
}
.footer-col__list{display:grid;gap:.1rem}
.footer-col__link{
  display:inline-block;padding:.28rem 0;
  font-size:.9375rem;color:var(--graphite);
  border-bottom:1px solid transparent;
  transition:color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
.footer-col__link:hover{color:var(--ink-900);border-bottom-color:var(--amber-500)}
.footer-col:nth-child(2){padding-top:1.25rem}
.footer-col:nth-child(3){padding-top:2.5rem}
.footer-contact__line{display:flex;gap:.55rem;font-size:.875rem;line-height:1.7;color:var(--graphite);word-break:break-word}
.footer-contact__key{flex:none;min-width:2.3em;padding-top:.2em;font-family:var(--font-mono);font-size:.625rem;letter-spacing:.1em;color:var(--ink-500)}
.footer-contact__note{margin-top:.7rem;font-size:.8125rem;line-height:1.7;color:var(--graphite-soft)}
.footer-base{
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:.5rem 1.25rem;
  margin-top:clamp(2rem,5vw,3rem);padding-top:1rem;
  border-top:1px solid var(--stone-200);
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.08em;color:var(--graphite-soft);
}
.footer-base__copy,.footer-base__icp{line-height:1.6}
.footer-stamp{
  position:absolute;right:var(--gutter);bottom:-.4rem;z-index:0;
  font-family:var(--font-mono);font-weight:200;
  font-size:clamp(2.75rem,9vw,7rem);line-height:1;letter-spacing:.04em;
  color:rgba(11,42,69,.07);
  pointer-events:none;user-select:none;
}

/* ===== 13 breadcrumbs ===== */
.breadcrumbs{
  display:flex;flex-wrap:wrap;align-items:center;gap:.35rem;
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.1em;text-transform:uppercase;
  color:var(--graphite-soft);
  margin-bottom:clamp(1rem,2.5vw,1.75rem);
}
.breadcrumbs li{display:inline-flex;align-items:center;gap:.35rem}
.breadcrumbs li:not(:last-child)::after{content:"/";color:var(--stone-200)}
.breadcrumbs a{color:var(--ink-500)}
.breadcrumbs a:hover{color:var(--ink-900)}
.breadcrumbs [aria-current="page"]{color:var(--graphite)}

/* ===== 14 prose ===== */
.prose{max-width:38em;font-size:var(--fs-md);line-height:1.78;color:var(--graphite)}
.prose>*+*{margin-top:1em}
.prose h2{margin-top:1.9em;font-size:clamp(1.35rem,2.4vw,1.625rem)}
.prose h3{margin-top:1.5em;font-size:1.125rem}
.prose ul,.prose ol{display:grid;gap:.45em;padding-left:1.1em}
.prose ul>li{list-style:none;position:relative}
.prose ul>li::before{content:"";position:absolute;left:-1.1em;top:.72em;width:8px;height:2px;background:var(--amber-500)}
.prose ol>li{list-style:decimal;font-variant-numeric:tabular-nums}
.prose a{color:var(--ink-500);box-shadow:inset 0 -1px 0 rgba(31,92,139,.4)}
.prose a:hover{color:var(--ink-900);box-shadow:inset 0 -2px 0 var(--amber-500)}
.prose blockquote{
  padding:.9rem 1.15rem;border-left:3px solid var(--amber-500);
  background:var(--paper-2);color:var(--ink-700);font-size:1.0625rem;
}

/* ===== 15 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--aside{grid-template-columns:minmax(0,7fr) minmax(0,5fr);align-items:start}

/* ===== 16 panels / tags / section head ===== */
.panel{
  position:relative;
  background:var(--paper-2);
  border:1px solid var(--stone-200);
  border-radius:var(--radius-m);
  padding:clamp(1.1rem,2.4vw,1.75rem);
  box-shadow:var(--shadow-sheet);
}
.panel::before{content:"";position:absolute;left:clamp(1.1rem,2.4vw,1.75rem);top:-1px;width:34px;height:3px;background:var(--amber-500)}
.panel__index{
  display:block;margin-bottom:.5rem;
  font-family:var(--font-mono);font-weight:300;font-size:1.5rem;letter-spacing:.06em;
  color:rgba(11,42,69,.28);line-height:1;
}
.tag{
  display:inline-flex;align-items:center;gap:.3rem;
  padding:.18rem .5rem;
  border:1px solid var(--stone-200);border-radius:var(--radius-s);
  font-family:var(--font-mono);font-size:.625rem;letter-spacing:.1em;text-transform:uppercase;
  color:var(--graphite-soft);background:var(--paper-2);
  white-space:nowrap;
}
.tag--ink{background:var(--ink-900);border-color:var(--ink-900);color:var(--paper-2)}
.tag--amber{background:rgba(224,163,62,.16);border-color:var(--amber-500);color:var(--ink-900)}
.tag--sage{background:var(--sage-500);border-color:var(--sage-500);color:var(--paper-2)}
.tag--coral{background:rgba(228,105,75,.14);border-color:var(--coral-500);color:#8E3A24}
.section-head{
  display:grid;grid-template-columns:minmax(0,1fr);gap:.5rem;
  padding-top:1.1rem;border-top:1px solid var(--stone-200);
  margin-bottom:clamp(1.25rem,3vw,2rem);
}
.section-head__index{
  display:block;
  font-family:var(--font-mono);font-weight:300;
  font-size:clamp(2.2rem,6.5vw,4.5rem);line-height:.85;letter-spacing:.04em;
  color:rgba(11,42,69,.14);
}
.section-head__title{font-size:clamp(1.4rem,2.8vw,2.125rem);font-weight:800;color:var(--ink-900)}
.section-head__note{max-width:36em;font-size:.9375rem;line-height:1.75;color:var(--graphite-soft)}

/* ===== 17 data table ===== */
.data-table{width:100%;border-collapse:collapse;font-size:.9375rem;line-height:1.6}
.data-table caption{
  text-align:left;padding-bottom:.7rem;
  font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.1em;text-transform:uppercase;color:var(--graphite-soft);
}
.data-table th,.data-table td{padding:.7rem .85rem;text-align:left;vertical-align:top;border-bottom:1px solid var(--stone-200)}
.data-table thead th{background:var(--sage-500);color:var(--paper-2);font-weight:700;border-bottom:0;white-space:nowrap}
.data-table tbody tr:hover td{background:rgba(217,222,226,.28)}
.data-table tr.is-current td{background:rgba(242,200,121,.18);box-shadow:inset 0 -1px 0 var(--amber-500),inset 0 1px 0 var(--amber-500)}
.data-table td.is-diff::after{content:"▲";margin-left:.4rem;font-size:.6rem;color:var(--coral-500);vertical-align:.15em}

/* ===== 18 filter protocol ===== */
[data-filter-bar],[data-filter-group]{display:flex;flex-wrap:wrap;gap:.4rem}
[data-filter]{
  padding:.5rem .9rem;border-radius:var(--radius-pill);
  border:1px solid var(--stone-200);background:var(--paper-2);
  font-size:.8125rem;font-weight:700;color:var(--ink-700);
  transition:background var(--dur) var(--ease),color var(--dur) var(--ease),border-color var(--dur) var(--ease);
}
[data-filter]:hover{border-color:var(--ink-500)}
[data-filter][aria-pressed="true"]{background:var(--ink-900);border-color:var(--ink-900);color:var(--paper-2)}
[data-filter-item][data-filtered="out"]{display:none!important}
[data-filter-count]{font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.1em;color:var(--graphite-soft)}

/* ===== 19 media / image frames ===== */
figure{margin:0}
.media-frame{
  position:relative;overflow:hidden;
  border:1px solid var(--stone-200);border-radius:var(--radius-m);
  background:var(--stone-100);
  box-shadow:var(--shadow-sheet);
}
.media-frame>img,.media-frame>svg,.media-frame>picture>img{width:100%;height:100%;object-fit:cover;display:block}
.media-frame--wide{aspect-ratio:16/9}
.media-frame--square{aspect-ratio:1/1}
.media-frame--tall{aspect-ratio:3/4}
.media-frame--blueprint{
  background-color:var(--ink-900);
  background-image:
    linear-gradient(rgba(247,244,236,.08) 1px,transparent 1px),
    linear-gradient(90deg,rgba(247,244,236,.08) 1px,transparent 1px);
  background-size:28px 28px;
  border-color:var(--ink-700);
}
.media-frame--paper{background:var(--paper-2)}
.media-caption{margin-top:.55rem;font-family:var(--font-mono);font-size:.6875rem;letter-spacing:.08em;color:var(--graphite-soft)}

/* ===== 20 reveal motion ===== */
html[data-motion="on"] [data-reveal]{
  opacity:0;transform:translateY(24px);
  transition:opacity var(--dur) var(--ease),transform var(--dur) var(--ease);
}
html[data-motion="on"] [data-reveal][data-revealed="true"]{opacity:1;transform:none}

/* ===== 21 responsive ===== */
@media (max-width:1120px){
  .site-nav__link{padding:.5rem .55rem;font-size:.875rem}
  .brand-note{display:none}
}

@media (max-width:960px){
  .header-shell{padding:.4rem .45rem .4rem .8rem;border-radius:22px}
  .nav-toggle{display:inline-flex}
  .site-nav{
    position:absolute;left:0;right:0;top:calc(100% + .5rem);
    display:none;flex-direction:column;align-items:stretch;gap:.3rem;
    margin:0;padding:.85rem;
    background:var(--paper-2);
    border:1px solid var(--stone-200);border-radius:20px;
    box-shadow:var(--shadow-float);
    max-height:calc(100vh - 7.5rem);overflow-y:auto;
  }
  .site-nav[data-open="true"]{display:flex}
  .site-nav__list{flex-direction:column;align-items:stretch;gap:.15rem}
  .site-nav__link{padding:.72rem .8rem;border-radius:12px;font-size:1rem}
  .site-nav__tools{
    flex-direction:column;align-items:stretch;gap:.6rem;
    margin:.55rem 0 0;padding:.8rem 0 0;
    border-left:0;border-top:1px solid var(--stone-200);
  }
  .version-switch{width:100%}
  .version-switch__trigger{width:100%;justify-content:space-between;padding:.62rem .8rem}
  .version-switch__menu{position:static;width:100%;margin-top:.55rem;box-shadow:none}
  .header-cta{width:100%;padding:.8rem 1rem}
  .grid--2,.grid--3,.grid--aside{grid-template-columns:minmax(0,1fr)}
  .footer-grid{grid-template-columns:minmax(0,1fr) minmax(0,1fr)}
  .footer-brand{grid-column:1/-1}
  .footer-nav{grid-template-columns:repeat(3,minmax(0,1fr))}
  .footer-col:nth-child(2),.footer-col:nth-child(3){padding-top:0}
}

@media (max-width:640px){
  .brand-name{font-size:1rem}
  .header-progress{margin-top:.3rem}
  .footer-grid{grid-template-columns:minmax(0,1fr)}
  .footer-nav{grid-template-columns:minmax(0,1fr);gap:1.1rem}
  .footer-base{flex-direction:column;align-items:flex-start}
  .footer-stamp{bottom:-.2rem;opacity:.9}
  .nav-toggle__label{display:none}
}

/* ===== 22 reduced motion ===== */
@media (prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{
    animation-duration:.01ms!important;
    animation-iteration-count:1!important;
    transition-duration:.01ms!important;
    scroll-behavior:auto!important;
  }
  html[data-motion="on"] [data-reveal]{opacity:1;transform:none}
  .btn:hover,.version-card:hover{transform:none}
}