:root{
  --ink:#12202b;
  --muted:#60717c;
  --bg:#f3f6fa;
  --panel:#fff;
  --line:#d7e0e7;
  --line-strong:#bdcbd5;
  --nav:#101820;
  --nav-soft:#1d2d38;
  --blue:#2764d8;
  --blue-soft:#edf4ff;
  --red:#b42318;
  --red-soft:#fff1f0;
  --amber:#a94f08;
  --amber-soft:#fff3df;
  --green:#087a50;
  --green-soft:#eafaf2;
  --violet:#6656d9;
  --shadow-sm:0 2px 8px rgba(16,24,32,.06);
  --shadow-md:0 16px 40px rgba(16,24,32,.10);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  background:
    radial-gradient(circle at 8% 2%,rgba(39,100,216,.08),transparent 28rem),
    radial-gradient(circle at 96% 12%,rgba(102,86,217,.07),transparent 26rem),
    var(--bg);
  color:var(--ink);
  line-height:1.58;
  text-rendering:optimizeLegibility;
  -webkit-font-smoothing:antialiased;
}
::selection{background:#dbe8ff;color:var(--ink)}
a{color:inherit}
button,input{font:inherit}
.skip-link{
  position:fixed;
  left:16px;
  top:-80px;
  z-index:100;
  padding:10px 14px;
  border:2px solid var(--blue);
  border-radius:10px;
  background:#fff;
  color:var(--ink);
  font-weight:850;
  text-decoration:none;
  box-shadow:var(--shadow-md);
}
.skip-link:focus{top:14px}
:focus-visible{outline:3px solid rgba(39,100,216,.42);outline-offset:3px}
.site-header{
  position:sticky;
  top:0;
  z-index:30;
  background:rgba(16,24,32,.95);
  color:#fff;
  border-bottom:1px solid rgba(255,255,255,.10);
  box-shadow:0 7px 26px rgba(16,24,32,.14);
  backdrop-filter:blur(16px);
}
.site-header::after{
  content:"";
  display:block;
  height:2px;
  background:linear-gradient(90deg,var(--blue),var(--violet),transparent 84%);
}
.header-inner{
  max-width:1180px;
  margin:auto;
  padding:14px 22px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
}
.brand{font-weight:900;letter-spacing:.005em}
.nav{display:flex;align-items:center;gap:4px;flex-wrap:wrap}
.nav a{
  padding:9px 11px;
  border-radius:9px;
  color:#eef4f7;
  text-decoration:none;
  font-size:14px;
  font-weight:720;
}
.nav a:hover,.nav a:focus-visible{background:rgba(255,255,255,.10);color:#fff}
.nav a.current,.nav a[aria-current="page"]{background:#fff;color:var(--nav)}
.container{max-width:1180px;margin:auto;padding:26px 22px 58px}
.demo-notice{
  position:relative;
  margin-bottom:18px;
  padding:14px 16px 14px 46px;
  border:1px solid #bdd0f4;
  border-radius:13px;
  background:rgba(237,244,255,.94);
  box-shadow:var(--shadow-sm);
}
.demo-notice::before{
  content:"S";
  position:absolute;
  left:15px;
  top:50%;
  transform:translateY(-50%);
  display:grid;
  place-items:center;
  width:23px;
  height:23px;
  border-radius:50%;
  background:var(--blue);
  color:#fff;
  font-size:11px;
  font-weight:900;
}
.eyebrow{text-transform:uppercase;letter-spacing:.11em;font-size:12px;font-weight:900;color:var(--blue)}
h1{margin:12px 0 20px;font-size:clamp(38px,6vw,68px);line-height:1.03;letter-spacing:-.035em}
h2{margin:0 0 16px;font-size:30px;line-height:1.15}
h3{margin:0 0 10px;line-height:1.3}
p{margin:0 0 15px}
.lead{max-width:800px;color:#344852;font-size:20px;line-height:1.55}
.small{color:var(--muted);font-size:13px}
.actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:26px}
.btn{
  min-height:44px;
  display:inline-flex;
  align-items:center;
  justify-content:center;
  border:1px solid transparent;
  border-radius:11px;
  padding:11px 16px;
  font-weight:850;
  cursor:pointer;
  text-decoration:none;
  transition:transform .16s ease,box-shadow .16s ease;
}
.btn:hover{transform:translateY(-2px)}
.btn.primary{background:linear-gradient(135deg,var(--nav),var(--nav-soft));color:#fff;box-shadow:0 8px 20px rgba(16,24,32,.20)}
.btn.secondary{border-color:var(--line-strong);background:#fff}
.grid{display:grid;gap:16px}
.grid.two{grid-template-columns:repeat(2,minmax(0,1fr))}
.grid.three{grid-template-columns:repeat(3,minmax(0,1fr))}
.card{
  padding:21px;
  border:1px solid var(--line);
  border-radius:17px;
  background:rgba(255,255,255,.95);
  box-shadow:var(--shadow-sm);
}
.card.highlight{box-shadow:var(--shadow-md)}
.kicker{color:var(--muted);font-size:12px;font-weight:900;letter-spacing:.08em;text-transform:uppercase}
.metric{margin:7px 0;font-size:28px;font-weight:950;line-height:1.15}
.red{color:var(--red)}
.amber{color:var(--amber)}
.green{color:var(--green)}
.section{padding:38px 0}
.app-nav{
  position:sticky;
  top:83px;
  z-index:20;
  display:flex;
  gap:4px;
  flex-wrap:nowrap;
  overflow-x:auto;
  scrollbar-width:thin;
  margin-bottom:18px;
  padding:8px;
  border:1px solid var(--line);
  border-radius:15px;
  background:rgba(255,255,255,.94);
  box-shadow:var(--shadow-md);
  backdrop-filter:blur(12px);
}
.app-nav button{
  min-height:41px;
  border:1px solid transparent;
  border-radius:10px;
  background:transparent;
  color:#40545f;
  padding:7px 9px;
  font-size:12px;
  white-space:nowrap;
  font-weight:820;
  cursor:pointer;
}
.app-nav button:hover{background:var(--blue-soft);color:var(--blue)}
.app-nav button.active{
  background:linear-gradient(135deg,var(--nav),var(--nav-soft));
  color:#fff;
  box-shadow:0 6px 15px rgba(16,24,32,.18);
}
.screen{display:none}
.screen.active{display:block;animation:screen-in .22s ease}
@keyframes screen-in{from{opacity:.55;transform:translateY(4px)}to{opacity:1;transform:none}}
.flag{
  margin:10px 0;
  padding:15px 16px;
  border:1px solid #f4c7c3;
  border-left:5px solid var(--red);
  border-radius:12px;
  background:var(--red-soft);
  cursor:pointer;
  transition:transform .15s ease,background .15s ease;
}
.flag:hover{transform:translateX(2px);background:#ffe8e5}
.detail-panel{display:none;margin-top:10px}
.detail-panel.active{display:block}
table{width:100%;border-collapse:collapse;font-size:14px}
th,td{padding:12px 10px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top}
th{color:var(--muted);font-size:12px;font-weight:900;letter-spacing:.05em;text-transform:uppercase}
tr.clickable{cursor:pointer}
tr.clickable:hover{background:#f6f9fc}
.trace{border-left:3px solid #c8d6e2;padding-left:18px}
.trace-step{position:relative;margin:0 0 17px}
.trace-step::before{
  content:"";
  position:absolute;
  left:-24px;
  top:5px;
  width:9px;
  height:9px;
  border:2px solid #fff;
  border-radius:50%;
  background:var(--blue);
  box-shadow:0 0 0 1px #aec3d4;
}
.askbar{display:flex;gap:10px}
.askbar input{
  min-height:46px;
  flex:1;
  border:1px solid var(--line-strong);
  border-radius:11px;
  background:#fff;
  padding:12px 14px;
  color:var(--ink);
  font-size:15px;
  box-shadow:inset 0 1px 2px rgba(16,24,32,.04);
}
.askbar input:focus{border-color:var(--blue)}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin:14px 0}
.chip{
  min-height:38px;
  border:1px solid var(--line);
  border-radius:999px;
  background:#eef3f6;
  color:#344852;
  padding:8px 11px;
  font-size:12px;
  font-weight:720;
  cursor:pointer;
}
.chip:hover{border-color:#aebfcc;background:var(--blue-soft);color:var(--blue)}
.answer{margin-top:16px}
.label{display:inline-block;margin-right:6px;padding:5px 8px;border-radius:7px;font-size:11px;font-weight:900}
.label.fact{background:#e0f2fe;color:#075985}
.label.inference{background:#ede9fe;color:#5b21b6}
.label.judgement{background:#fef3c7;color:#92400e}
.label.limit{background:#fee2e2;color:#991b1b}
.info-wrap{display:inline-flex;position:relative;align-items:center}
.info-btn{
  width:22px;
  height:22px;
  margin-left:5px;
  border:0;
  border-radius:50%;
  background:#e7edf0;
  color:#24323a;
  font-size:12px;
  font-weight:900;
  cursor:pointer;
}
.popover{
  display:none;
  position:absolute;
  z-index:40;
  top:30px;
  left:0;
  width:270px;
  padding:13px;
  border-radius:11px;
  background:var(--nav);
  color:#fff;
  font-size:13px;
  line-height:1.45;
  box-shadow:var(--shadow-md);
}
.popover.open{display:block}
.notice{padding:14px 15px;border:1px solid #bdd0f4;border-radius:11px;background:var(--blue-soft)}
.notice.demo-notice{padding:14px 16px 14px 46px}
footer{border-top:1px solid var(--line);padding:28px 0;color:var(--muted);font-size:13px}
@media(max-width:820px){
  .site-header{position:relative}
  .header-inner{align-items:flex-start;flex-direction:column;padding:13px 18px}
  .nav{width:100%;overflow-x:auto;flex-wrap:nowrap}
  .nav a{white-space:nowrap}
  .container{padding-left:17px;padding-right:17px}
  .grid.two,.grid.three{grid-template-columns:1fr}
  .app-nav{position:static;flex-wrap:nowrap;overflow-x:auto;padding-bottom:9px;scrollbar-width:thin}
  .app-nav button{white-space:nowrap}
  .askbar{flex-direction:column}
  table{display:block;overflow-x:auto;white-space:nowrap}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition:none!important;animation:none!important}
}