/* ============================================================
   PTRI INNOVATION — design system
   Concept: "The Build Floor" — engineering blueprint precision
   meets product-grade polish.
   ============================================================ */

:root{
  /* surfaces */
  --void:#08090b;
  --void-2:#0d0f13;
  --void-3:#14171d;
  --paper:#efece4;
  --paper-2:#e5e1d7;

  /* ink */
  --ink:#f6f4ef;
  --ink-2:#a8a69d;
  --ink-3:#66645d;
  --ink-inv:#14161a;

  /* signal */
  --volt:#ff4d19;
  --cyan:#38bdf8;
  --teal:#3ecfb2;
  --amber:#f5b324;

  /* lines */
  --line:rgba(246,244,239,.09);
  --line-2:rgba(246,244,239,.16);
  --line-3:rgba(246,244,239,.28);

  /* type */
  --f-sans:'Inter Tight','Inter',-apple-system,BlinkMacSystemFont,sans-serif;
  --f-serif:'Instrument Serif',Georgia,serif;
  --f-mono:'JetBrains Mono',ui-monospace,SFMono-Regular,monospace;

  /* metrics */
  --gut:clamp(20px,4vw,40px);
  --max:1320px;
  --ease:cubic-bezier(.16,1,.3,1);
}

*,*::before,*::after{margin:0;padding:0;box-sizing:border-box}
html{-webkit-text-size-adjust:100%}
body{
  background:var(--void);
  color:var(--ink);
  font-family:var(--f-sans);
  font-weight:350;
  font-size:16px;
  line-height:1.6;
  letter-spacing:-.008em;
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  overflow-x:hidden;
}
::selection{background:var(--volt);color:#fff}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}
button,input,select,textarea{font:inherit;color:inherit}
:focus-visible{outline:2px solid var(--volt);outline-offset:3px;border-radius:2px}

/* grain overlay */
body::after{
  content:"";position:fixed;inset:0;pointer-events:none;z-index:9000;
  opacity:.035;mix-blend-mode:overlay;
  background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='140' height='140'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------- layout ---------- */
.wrap{width:100%;max-width:var(--max);margin:0 auto;padding:0 var(--gut)}
.sec{position:relative;padding:clamp(70px,8.5vw,116px) 0}
.sec-tight{padding:clamp(48px,5.5vw,74px) 0}
.rule{height:1px;background:var(--line);border:0}
.grid{display:grid;gap:clamp(20px,2.4vw,32px)}

/* blueprint tick marks at section corners */
.ticks{position:absolute;inset:0;pointer-events:none}
.ticks i{position:absolute;width:11px;height:11px;opacity:.4}
.ticks i::before,.ticks i::after{content:"";position:absolute;background:var(--line-3)}
.ticks i::before{left:50%;top:0;width:1px;height:100%;transform:translateX(-50%)}
.ticks i::after{top:50%;left:0;height:1px;width:100%;transform:translateY(-50%)}
.ticks i:nth-child(1){left:calc(var(--gut) - 5px);top:-5px}
.ticks i:nth-child(2){right:calc(var(--gut) - 5px);top:-5px}

/* ---------- type ---------- */
h1,h2,h3,h4{font-weight:600;line-height:1.02;letter-spacing:-.042em}
.d1{font-size:clamp(2.8rem,7.6vw,6.6rem);font-weight:650;letter-spacing:-.055em;line-height:.92}
.d2{font-size:clamp(2.4rem,6.2vw,5.2rem);letter-spacing:-.05em;line-height:.96}
.d3{font-size:clamp(1.7rem,3.1vw,2.7rem);letter-spacing:-.04em;line-height:1.04}
.d4{font-size:clamp(1.15rem,1.7vw,1.42rem);letter-spacing:-.03em;line-height:1.2;font-weight:550}
em,.ser{font-family:var(--f-serif);font-style:italic;font-weight:400;letter-spacing:-.02em}
.d1 em,.d2 em{font-size:1.04em}
.lead{font-size:clamp(1.05rem,1.5vw,1.28rem);color:var(--ink-2);max-width:60ch;font-weight:330}
.small{font-size:.94rem;color:var(--ink-2)}
.mono{font-family:var(--f-mono);font-weight:400}

.kicker{
  display:inline-flex;align-items:center;gap:10px;
  font-family:var(--f-mono);font-size:11px;font-weight:500;
  letter-spacing:.2em;text-transform:uppercase;color:var(--ink-3);
}
.kicker b{color:var(--volt);font-weight:500}
.kicker::before{content:"";width:22px;height:1px;background:var(--line-2)}

.chip{
  display:inline-flex;align-items:center;gap:9px;
  font-family:var(--f-mono);font-size:10.5px;letter-spacing:.17em;text-transform:uppercase;
  color:var(--ink-2);border:1px solid var(--line-2);border-radius:100px;padding:7px 15px;
  background:rgba(246,244,239,.02);
}
.dot{width:6px;height:6px;border-radius:50%;background:var(--teal);flex:none;
  box-shadow:0 0 0 0 rgba(62,207,178,.55);animation:pulse 2.6s infinite}
.dot.o{background:var(--volt);box-shadow:0 0 0 0 rgba(255,77,25,.55)}
.dot.a{background:var(--amber);box-shadow:0 0 0 0 rgba(245,179,36,.55)}
.dot.c{background:var(--cyan);box-shadow:0 0 0 0 rgba(56,189,248,.55)}
@keyframes pulse{70%{box-shadow:0 0 0 9px transparent}100%{box-shadow:0 0 0 0 transparent}}

/* ---------- buttons ---------- */
.btn{
  display:inline-flex;align-items:center;gap:11px;position:relative;
  padding:15px 26px;border-radius:100px;font-size:.94rem;font-weight:450;
  letter-spacing:-.01em;border:1px solid transparent;cursor:pointer;
  transition:background .3s var(--ease),color .3s var(--ease),border-color .3s var(--ease),transform .3s var(--ease);
  white-space:nowrap;
}
.btn .ar{transition:transform .35s var(--ease);display:inline-block}
.btn:hover .ar{transform:translateX(5px)}
.btn-solid{background:var(--ink);color:var(--ink-inv)}
.btn-solid:hover{background:var(--volt);color:#fff;transform:translateY(-2px)}
.btn-ghost{border-color:var(--line-2);color:var(--ink)}
.btn-ghost:hover{border-color:var(--ink);background:rgba(246,244,239,.05)}
.btn-volt{background:var(--volt);color:#fff}
.btn-volt:hover{transform:translateY(-2px);filter:brightness(1.08)}
.btn-sm{padding:11px 19px;font-size:.86rem}

.tlink{display:inline-flex;align-items:center;gap:9px;font-size:.95rem;color:var(--ink);
  padding-bottom:4px;border-bottom:1px solid var(--line-2);transition:border-color .3s,color .3s}
.tlink:hover{border-color:var(--volt);color:var(--volt)}
.tlink .ar{transition:transform .35s var(--ease)}
.tlink:hover .ar{transform:translate(4px,-4px)}

/* ---------- nav ---------- */
.nav{
  position:fixed;top:0;left:0;right:0;z-index:1000;
  display:flex;align-items:center;justify-content:space-between;
  padding:18px var(--gut);
  border-bottom:1px solid transparent;
  transition:background .45s var(--ease),padding .45s var(--ease),border-color .45s;
}
.nav.on{background:rgba(8,9,11,.82);backdrop-filter:blur(16px) saturate(140%);
  -webkit-backdrop-filter:blur(16px) saturate(140%);border-bottom-color:var(--line);padding:12px var(--gut)}
.brand{display:flex;align-items:center;gap:11px}
.mark{display:grid;grid-template-columns:repeat(2,7px);gap:3px;flex:none}
.mark span{width:7px;height:7px;border-radius:2px;transition:transform .4s var(--ease)}
.mark span:nth-child(1){background:var(--volt)}
.mark span:nth-child(2){background:var(--cyan)}
.mark span:nth-child(3){background:var(--teal)}
.mark span:nth-child(4){background:var(--amber)}
.brand:hover .mark span:nth-child(1){transform:translate(-2px,-2px)}
.brand:hover .mark span:nth-child(2){transform:translate(2px,-2px)}
.brand:hover .mark span:nth-child(3){transform:translate(-2px,2px)}
.brand:hover .mark span:nth-child(4){transform:translate(2px,2px)}
.brand-txt{display:flex;flex-direction:column;line-height:1}
.brand-txt b{font-size:1.02rem;font-weight:600;letter-spacing:-.035em}
.brand-txt small{font-family:var(--f-mono);font-size:8.5px;letter-spacing:.22em;
  text-transform:uppercase;color:var(--ink-3);margin-top:3px}

.nav-mid{display:flex;align-items:center;gap:4px}
.nav-mid > a,.nav-drop > button{
  font-size:.9rem;color:var(--ink-2);padding:9px 14px;border-radius:100px;
  transition:color .25s,background .25s;background:none;border:0;cursor:pointer;
  display:inline-flex;align-items:center;gap:6px;font-weight:400;letter-spacing:-.01em;
}
.nav-mid > a:hover,.nav-drop:hover > button,.nav-mid > a[aria-current]{color:var(--ink);background:rgba(246,244,239,.06)}
.nav-drop{position:relative}
.nav-drop > button svg{transition:transform .3s;opacity:.6}
.nav-drop:hover > button svg{transform:rotate(180deg)}
.dropdown{
  position:absolute;top:calc(100% + 8px);left:50%;transform:translate(-50%,8px);
  min-width:312px;background:rgba(13,15,19,.97);backdrop-filter:blur(20px);
  border:1px solid var(--line-2);border-radius:16px;padding:8px;
  opacity:0;visibility:hidden;transition:all .28s var(--ease);
  box-shadow:0 24px 60px rgba(0,0,0,.6);
}
.nav-drop:hover .dropdown,.nav-drop:focus-within .dropdown{opacity:1;visibility:visible;transform:translate(-50%,0)}
.dropdown a{display:flex;gap:12px;align-items:flex-start;padding:11px 13px;border-radius:11px;transition:background .22s}
.dropdown a:hover{background:rgba(246,244,239,.06)}
.dropdown a i{width:7px;height:7px;border-radius:50%;flex:none;margin-top:7px}
.dropdown a span{display:block;font-size:.9rem;color:var(--ink);font-weight:450;letter-spacing:-.015em}
.dropdown a small{display:block;font-size:.76rem;color:var(--ink-3);line-height:1.45;margin-top:1px}
.burger{display:none;flex-direction:column;gap:5px;padding:9px;background:none;border:0;cursor:pointer}
.burger i{width:22px;height:1.5px;background:var(--ink);transition:.35s var(--ease);display:block}
.burger.x i:nth-child(1){transform:translateY(6.5px) rotate(45deg)}
.burger.x i:nth-child(2){opacity:0}
.burger.x i:nth-child(3){transform:translateY(-6.5px) rotate(-45deg)}

.sheet{
  position:fixed;inset:0;z-index:999;background:var(--void);
  padding:96px var(--gut) 40px;display:flex;flex-direction:column;gap:2px;
  clip-path:inset(0 0 100% 0);transition:clip-path .55s var(--ease);overflow-y:auto;
}
.sheet.open{clip-path:inset(0 0 0 0)}
.sheet a{font-size:clamp(1.7rem,7vw,2.4rem);font-weight:600;letter-spacing:-.045em;
  padding:11px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;align-items:center}
.sheet a small{font-family:var(--f-mono);font-size:10px;color:var(--ink-3);letter-spacing:.16em}
.sheet .sub{font-size:1.05rem;font-weight:400;color:var(--ink-2);padding-left:18px}

/* ---------- reveal ---------- */
.rv{opacity:0;transform:translateY(26px);transition:opacity .9s var(--ease),transform .9s var(--ease)}
.rv.in{opacity:1;transform:none}
.rv[data-d="1"]{transition-delay:.08s}.rv[data-d="2"]{transition-delay:.16s}
.rv[data-d="3"]{transition-delay:.24s}.rv[data-d="4"]{transition-delay:.32s}
.rv[data-d="5"]{transition-delay:.4s}.rv[data-d="6"]{transition-delay:.48s}

/* ---------- section head ---------- */
.head{display:grid;grid-template-columns:1fr;gap:22px;margin-bottom:clamp(40px,5vw,64px)}
.head-row{display:flex;flex-wrap:wrap;gap:28px;align-items:flex-end;justify-content:space-between}

/* ---------- paper (light) sections ---------- */
.on-paper{
  --ink:var(--ink-inv);--ink-2:#5c5a54;--ink-3:#8e8b83;
  --line:rgba(20,22,26,.1);--line-2:rgba(20,22,26,.18);--line-3:rgba(20,22,26,.3);
  background:var(--paper);color:var(--ink-inv);
}
.on-paper .btn-solid{background:var(--ink-inv);color:var(--paper)}
.on-paper .btn-solid:hover{background:var(--volt);color:#fff}

/* ---------- footer ---------- */
.foot{border-top:1px solid var(--line);padding:clamp(56px,7vw,84px) 0 30px;background:var(--void-2)}
.foot-grid{display:grid;grid-template-columns:1.6fr repeat(3,1fr);gap:40px}
.foot h5{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--ink-3);font-weight:500;margin-bottom:18px}
.foot ul{list-style:none;display:flex;flex-direction:column;gap:11px}
.foot ul a{font-size:.93rem;color:var(--ink-2);transition:color .25s}
.foot ul a:hover{color:var(--volt)}
.foot-bot{display:flex;flex-wrap:wrap;gap:16px;justify-content:space-between;align-items:center;
  margin-top:clamp(44px,6vw,70px);padding-top:24px;border-top:1px solid var(--line)}
.foot-bot p{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.14em;text-transform:uppercase;color:var(--ink-3)}

/* ---------- marquee ---------- */
.marq{overflow:hidden;border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:18px 0;
  -webkit-mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent);
  mask-image:linear-gradient(90deg,transparent,#000 8%,#000 92%,transparent)}
.marq-in{display:flex;gap:44px;width:max-content;animation:slide 38s linear infinite}
.marq:hover .marq-in{animation-play-state:paused}
.marq span{font-family:var(--f-mono);font-size:12px;letter-spacing:.2em;text-transform:uppercase;
  color:var(--ink-3);display:inline-flex;align-items:center;gap:44px;white-space:nowrap}
.marq span::after{content:"◆";color:var(--volt);font-size:8px;opacity:.7}
@keyframes slide{to{transform:translateX(-50%)}}

/* ---------- breadcrumb ---------- */
.crumb{display:flex;align-items:center;gap:9px;font-family:var(--f-mono);font-size:10.5px;
  letter-spacing:.15em;text-transform:uppercase;color:var(--ink-3);flex-wrap:wrap}
.crumb a{transition:color .25s}
.crumb a:hover{color:var(--volt)}
.crumb i{opacity:.45;font-style:normal}
.crumb b{color:var(--ink);font-weight:400}

/* ---------- page hero ---------- */
.phero{padding:clamp(130px,16vw,190px) 0 clamp(50px,6vw,80px);position:relative;overflow:hidden}
.phero .bp{position:absolute;inset:0;z-index:0;opacity:.55;
  background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);
  background-size:76px 76px;
  -webkit-mask-image:radial-gradient(ellipse 90% 80% at 50% 25%,#000,transparent);
  mask-image:radial-gradient(ellipse 90% 80% at 50% 25%,#000,transparent)}
.phero .wrap{position:relative;z-index:1}

/* ---------- cards ---------- */
.card{border:1px solid var(--line);border-radius:20px;background:var(--void-2);
  transition:border-color .4s var(--ease),transform .4s var(--ease),background .4s}
.card:hover{border-color:var(--line-2);transform:translateY(-3px)}

/* ---------- misc ---------- */
.tags{display:flex;flex-wrap:wrap;gap:7px}
.tag{font-family:var(--f-mono);font-size:10px;letter-spacing:.1em;text-transform:uppercase;
  color:var(--ink-2);border:1px solid var(--line);border-radius:6px;padding:5px 9px}
.hidden-sm{display:initial}

/* ---------- responsive ---------- */
@media (max-width:1080px){
  .nav-mid{display:none}
  .burger{display:flex}
  .foot-grid{grid-template-columns:1fr 1fr;gap:34px}
  .nav .btn{display:none}
}
@media (max-width:640px){
  .foot-grid{grid-template-columns:1fr}
  .head-row{align-items:flex-start}
  .hidden-sm{display:none}
}
@media (prefers-reduced-motion:reduce){
  *{animation-duration:.01ms !important;animation-iteration-count:1 !important;
    transition-duration:.01ms !important;scroll-behavior:auto !important}
  .rv{opacity:1;transform:none}
}

/* ---------- Dwello face ---------- */
.dw-host{display:block;width:100%;max-width:250px;cursor:pointer;-webkit-tap-highlight-color:transparent}
.dw-svg{width:100%;height:auto;overflow:visible}
.dw-eye,.dw-mouth{transition:width .16s ease,height .16s ease,x .16s ease,y .16s ease,rx .16s ease}
.dw-head{transform-origin:120px 100px;transition:transform .45s var(--ease)}
.dw-bot{transform-origin:120px 230px}
.dw-bounce{animation:dwBounce .55s var(--ease)}
@keyframes dwBounce{0%{transform:translateY(0) scale(1)}30%{transform:translateY(-11px) scale(1.03,.97)}
  60%{transform:translateY(2px) scale(.99,1.01)}100%{transform:translateY(0) scale(1)}}
.dw-arm-r{transform-origin:186px 156px;animation:dwWave 3.4s var(--ease) infinite}
@keyframes dwWave{0%,62%,100%{transform:rotate(0deg)}70%{transform:rotate(-38deg)}78%{transform:rotate(-18deg)}86%{transform:rotate(-38deg)}}
.dw-shadow{animation:dwShadow 3.6s ease-in-out infinite}
@keyframes dwShadow{50%{opacity:.3;transform:scaleX(.94)}}

/* ---------- shared page components ---------- */
.facts{list-style:none;border-top:1px solid var(--line)}
.facts li{display:flex;justify-content:space-between;gap:18px;padding:13px 0;border-bottom:1px solid var(--line);font-size:.93rem}
.facts span{font-family:var(--f-mono);font-size:9.5px;letter-spacing:.17em;text-transform:uppercase;color:var(--ink-3);padding-top:3px}
.facts b{font-weight:450;text-align:right}

.fgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:1px;background:var(--line);
  border:1px solid var(--line);border-radius:20px;overflow:hidden}
.fgrid article{background:var(--void);padding:clamp(22px,2.5vw,32px);transition:background .4s}
.fgrid article:hover{background:var(--void-3)}
.fgrid .n{font-family:var(--f-mono);font-size:10px;letter-spacing:.2em;color:var(--ac,var(--volt));display:block;margin-bottom:18px}
.fgrid h3{font-size:1.1rem;letter-spacing:-.03em;margin-bottom:9px}
.fgrid p{font-size:.9rem;color:var(--ink-2)}
@media(max-width:900px){.fgrid{grid-template-columns:1fr 1fr}}
@media(max-width:600px){.fgrid{grid-template-columns:1fr}}

.shot{border:1px solid var(--line);border-radius:18px;overflow:hidden;background:var(--void-2)}
.shot .bar{display:flex;align-items:center;gap:7px;padding:11px 14px;border-bottom:1px solid var(--line)}
.shot .bar i{width:8px;height:8px;border-radius:50%;background:var(--line-3);display:block}
.shot .bar span{margin-left:8px;font-family:var(--f-mono);font-size:10px;letter-spacing:.12em;color:var(--ink-3)}
.shot img{width:100%;display:block}

.idx{border-top:1px solid var(--line-2)}
.idx a{display:grid;grid-template-columns:38px minmax(0,1.15fr) minmax(0,1.5fr) 150px 40px;gap:clamp(12px,2vw,28px);
  align-items:center;padding:20px 0;border-bottom:1px solid var(--line);transition:padding-left .4s var(--ease),background .4s}
.idx a:hover{padding-left:12px}
.idx .n{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.16em;color:var(--ink-3)}
.idx h3{font-size:clamp(1.25rem,2.2vw,1.7rem);letter-spacing:-.04em}
.idx .dom{font-family:var(--f-mono);font-size:10.5px;letter-spacing:.1em;color:var(--ink-3);display:block;margin-top:4px}
.idx p{font-size:.92rem;color:var(--ink-2)}
.idx .st{font-family:var(--f-mono);font-size:9.5px;letter-spacing:.16em;text-transform:uppercase;
  border:1px solid var(--line-2);border-radius:100px;padding:6px 12px;text-align:center;white-space:nowrap}
.idx .go{width:36px;height:36px;border-radius:50%;border:1px solid var(--line-2);display:grid;place-items:center;
  transition:.35s var(--ease);justify-self:end}
.idx a:hover .go{background:var(--volt);border-color:var(--volt);color:#fff;transform:rotate(-45deg)}
@media(max-width:1000px){.idx a{grid-template-columns:32px 1fr auto;row-gap:10px}
  .idx p{grid-column:2/4}.idx .go{display:none}}

.split{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.08fr);gap:clamp(28px,4.4vw,64px);align-items:center}
@media(max-width:900px){.split{grid-template-columns:1fr}}

/* ---------- document pages (legal / support) ---------- */
.docprog{position:fixed;top:0;left:0;height:2px;width:0;z-index:1001;
  background:linear-gradient(90deg,var(--ac,var(--volt)),color-mix(in srgb,var(--ac,var(--volt)) 55%,#fff));
  transition:width .1s linear;box-shadow:0 0 12px color-mix(in srgb,var(--ac,var(--volt)) 60%,transparent)}

.dochead{position:relative;overflow:hidden;padding:clamp(112px,13vw,150px) 0 clamp(34px,4vw,52px);
  border-bottom:1px solid var(--line)}
.dochead .bp{position:absolute;inset:0;z-index:0;opacity:.5;
  background-image:linear-gradient(var(--line) 1px,transparent 1px),linear-gradient(90deg,var(--line) 1px,transparent 1px);
  background-size:76px 76px;
  -webkit-mask-image:radial-gradient(ellipse 90% 80% at 50% 20%,#000,transparent);
  mask-image:radial-gradient(ellipse 90% 80% at 50% 20%,#000,transparent)}
.dochead .wrap{position:relative;z-index:2}
.dochead h1{font-size:clamp(2.5rem,6.4vw,4.6rem);letter-spacing:-.052em;line-height:.98;margin:22px 0 0}
.docmeta{display:grid;grid-template-columns:repeat(auto-fit,minmax(168px,1fr));gap:1px;
  background:var(--line);border:1px solid var(--line);border-radius:14px;overflow:hidden;margin-top:30px}
.docmeta div{background:var(--void-2);padding:15px 18px}
.docmeta small{display:block;font-family:var(--f-mono);font-size:9px;letter-spacing:.19em;
  text-transform:uppercase;color:var(--ink-3);margin-bottom:6px}
.docmeta b{font-size:.92rem;font-weight:500;letter-spacing:-.015em}

/* app lockup */
.applock{display:flex;align-items:center;gap:16px}
.applock img{width:66px;height:66px;border-radius:16px;flex:none;
  box-shadow:0 12px 34px rgba(0,0,0,.55),0 0 0 1px rgba(255,255,255,.07)}
.applock b{display:block;font-size:1.12rem;font-weight:600;letter-spacing:-.035em;line-height:1.2}
.applock small{display:block;font-family:var(--f-mono);font-size:9.5px;letter-spacing:.19em;
  text-transform:uppercase;color:var(--ink-3);margin-top:5px}

/* segmented doc switcher */
.docnav{display:inline-flex;gap:4px;margin-top:28px;padding:4px;
  border:1px solid var(--line-2);border-radius:100px;background:var(--void-2)}
.docnav a{font-family:var(--f-mono);font-size:10px;letter-spacing:.16em;text-transform:uppercase;
  border-radius:100px;padding:9px 17px;color:var(--ink-3);transition:.28s var(--ease)}
.docnav a:hover{color:var(--ink)}
.docnav a[aria-current]{background:var(--ac,var(--volt));color:#fff}

/* at-a-glance tiles */
.glance{display:grid;grid-template-columns:repeat(2,1fr);gap:1px;
  background:var(--line);border:1px solid var(--line);border-radius:18px;overflow:hidden;margin-bottom:clamp(30px,4vw,44px)}
.glance div{background:var(--void-2);padding:22px 22px 24px;transition:background .4s}
.glance div:hover{background:var(--void-3)}
.glance .ic{width:32px;height:32px;border-radius:9px;display:grid;place-items:center;margin-bottom:16px;
  border:1px solid color-mix(in srgb,var(--ac,var(--volt)) 40%,transparent);
  background:color-mix(in srgb,var(--ac,var(--volt)) 10%,transparent);color:var(--ac,var(--volt))}
.glance b{display:block;font-size:.99rem;font-weight:550;letter-spacing:-.025em;margin-bottom:6px}
.glance p{font-size:.85rem;color:var(--ink-2);line-height:1.6}

/* quick actions */
.qa{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-bottom:clamp(28px,4vw,40px)}
.qa a{border:1px solid var(--line);border-radius:15px;background:var(--void-2);padding:20px;
  display:flex;flex-direction:column;gap:7px;transition:border-color .35s var(--ease),transform .35s var(--ease),background .35s}
.qa a:hover{border-color:color-mix(in srgb,var(--ac,var(--volt)) 55%,transparent);transform:translateY(-2px);background:var(--void-3)}
.qa small{font-family:var(--f-mono);font-size:9px;letter-spacing:.19em;text-transform:uppercase;color:var(--ink-3)}
.qa b{font-size:.99rem;font-weight:550;letter-spacing:-.025em;display:flex;justify-content:space-between;gap:12px;align-items:center}
.qa b .ar{color:var(--ac,var(--volt));transition:transform .35s var(--ease)}
.qa a:hover b .ar{transform:translateX(4px)}
.qa p{font-size:.85rem;color:var(--ink-2);line-height:1.55}

/* layout */
.docwrap{display:grid;grid-template-columns:248px minmax(0,1fr);gap:clamp(26px,4vw,68px);align-items:start;
  padding:clamp(40px,5vw,66px) 0 clamp(60px,7vw,96px)}
.toc{position:sticky;top:92px}
.toc h5{font-family:var(--f-mono);font-size:9.5px;letter-spacing:.2em;text-transform:uppercase;color:var(--ink-3);
  font-weight:500;margin-bottom:16px;display:flex;justify-content:space-between;align-items:center}
.toc h5 span{color:var(--ac,var(--volt))}
.toc .railwrap{position:relative}
.toc ol{list-style:none;border-left:1px solid var(--line-2);counter-reset:toc}
.toc a{display:block;padding:8px 0 8px 18px;font-size:.855rem;color:var(--ink-3);line-height:1.45;
  transition:color .28s}
.toc a:not(.sub){counter-increment:toc}
.toc a.sub{padding:5px 0 5px 40px;font-size:.79rem;opacity:.8}
.toc a.sub::before{content:"";width:5px;height:1px;background:currentColor;display:inline-block;
  margin:0 9px 4px -14px;opacity:.6}
.toc a.sub.on{opacity:1}
.toc a:not(.sub)::before{content:counter(toc,decimal-leading-zero);font-family:var(--f-mono);font-size:9px;
  letter-spacing:.12em;color:var(--ink-3);opacity:.55;margin-right:9px}
.toc a:hover{color:var(--ink-2)}
.toc a.on{color:var(--ink)}
.toc a.on::before{color:var(--ac,var(--volt));opacity:1}
/* the travelling focus dot — the app's red bar + dot, as navigation */
.tocdot{position:absolute;left:-4px;top:0;width:7px;height:7px;border-radius:50%;
  background:var(--ac,var(--volt));box-shadow:0 0 0 4px color-mix(in srgb,var(--ac,var(--volt)) 18%,transparent);
  transition:top .38s var(--ease);pointer-events:none}

/* prose */
.prose{max-width:74ch}
.prose h2{font-size:clamp(1.32rem,2.2vw,1.74rem);letter-spacing:-.035em;line-height:1.2;
  margin:clamp(40px,4.2vw,56px) 0 15px;scroll-margin-top:96px;display:flex;gap:13px;align-items:baseline}
.prose > h2:first-child{margin-top:0}
.prose h2 .n{font-family:var(--f-mono);font-size:.6em;letter-spacing:.14em;color:var(--ac,var(--volt));
  font-weight:400;flex:none}
.prose h3{font-size:1.04rem;font-weight:550;letter-spacing:-.025em;margin:30px 0 10px;color:var(--ink);
  scroll-margin-top:96px}
.prose p{color:var(--ink-2);margin-bottom:14px;font-size:1rem;line-height:1.75}
.prose ul{list-style:none;margin:0 0 16px;display:grid;gap:9px}
.prose ul li{display:flex;gap:12px;color:var(--ink-2);font-size:.98rem;line-height:1.65}
.prose ul li::before{content:"";width:5px;height:5px;border-radius:50%;background:var(--line-3);flex:none;margin-top:9px}
.prose strong{color:var(--ink);font-weight:550}
.prose a{color:var(--ink);border-bottom:1px solid var(--line-2);transition:color .25s,border-color .25s;word-break:break-word}
.prose a:hover{color:var(--ac,var(--volt));border-color:var(--ac,var(--volt))}
.prose hr{border:0;border-top:1px solid var(--line);margin:clamp(34px,4vw,48px) 0}
.prose .callout{position:relative;border:1px solid var(--line);border-radius:16px;background:var(--void-2);
  padding:20px 24px 20px 26px;margin:24px 0;overflow:hidden}
.prose .callout::before{content:"";position:absolute;left:0;top:14px;bottom:14px;width:3px;border-radius:2px;
  background:var(--ac,var(--volt))}
.prose .callout p{margin-bottom:0;color:var(--ink)}
.prose .formula{font-family:var(--f-mono);font-size:.93rem;color:var(--ink);background:var(--void-3);
  border:1px solid var(--line-2);border-radius:12px;padding:16px 20px;margin:16px 0;overflow-x:auto}
.prose .addr{font-style:normal;color:var(--ink-2);line-height:1.85;font-size:.98rem;
  border:1px solid var(--line);border-radius:16px;background:var(--void-2);padding:22px 24px}
.prose .addr b{color:var(--ink);font-weight:600;font-size:1.02rem}

@media(max-width:620px){.glance,.qa{grid-template-columns:1fr}}
@media(max-width:960px){
  .docwrap{grid-template-columns:1fr;gap:24px}
  .toc{position:static;border:1px solid var(--line);border-radius:16px;padding:20px 22px;background:var(--void-2)}
  .toc ol{max-height:210px;overflow-y:auto}
  .tocdot{display:none}
}

/* components inside .prose keep their own link styling (beats the prose <a> rule) */
.prose .btn{border-bottom:0}
.prose .btn-solid{color:var(--ink-inv)}
.prose .btn-solid:hover{color:#fff}
.prose .qa a{border-bottom:1px solid var(--line)}
.prose .qa a:hover{border-bottom-color:color-mix(in srgb,var(--ac,var(--volt)) 55%,transparent)}
.prose .addr a{border-bottom:1px solid var(--line-2)}