/* ============================================================
   Flow Control — project page
   Palette + type inherit from kaolab.org; layout is bespoke,
   themed on "flow / steering".
   ============================================================ */
:root{
  --paper:#F4F1EA;
  --paper-2:#EDE9DF;
  --ink:#121212;
  --ink-2:#2a2a28;
  --muted:#6b6a63;
  --rule:rgba(18,18,18,0.14);
  --rule-2:rgba(18,18,18,0.08);
  --accent: oklch(0.58 0.17 252);   /* blue — primary */
  --accent-2: oklch(0.70 0.17 55);   /* amber */
  --accent-3: oklch(0.62 0.18 285);  /* violet */
  --maxw:1180px;
}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
html,body{
  margin:0;padding:0;background:var(--paper);color:var(--ink);
  font-family:'Inter',system-ui,sans-serif;font-weight:400;
  -webkit-font-smoothing:antialiased;
}
section[id]{scroll-margin-top:84px}
a{color:inherit;text-decoration:none}
img{max-width:100%;display:block}

.mono{font-family:'JetBrains Mono',ui-monospace,monospace;font-size:11px;letter-spacing:0.08em;text-transform:uppercase}
em{font-family:'Instrument Serif',Georgia,serif;font-weight:400;font-style:italic}

.page{max-width:var(--maxw);margin:0 auto;padding:0 28px}

/* ===== nav ===== */
header.top{
  position:sticky;top:0;z-index:40;
  backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);
  background:color-mix(in oklab, var(--paper) 82%, transparent);
  border-bottom:1px solid var(--rule-2);
}
.nav{display:flex;align-items:center;justify-content:space-between;height:64px;gap:24px}
.brand{display:flex;align-items:center;gap:10px;font-weight:600;letter-spacing:-0.01em;font-size:15px}
.brand .dot{width:9px;height:9px;border-radius:50%;background:var(--accent);
  box-shadow:0 0 0 4px color-mix(in oklab, var(--accent) 28%, transparent)}
.nav ul{display:flex;gap:22px;list-style:none;padding:0;margin:0}
.nav ul a{font-size:13.5px;color:var(--ink-2);transition:color .2s}
.nav ul a:hover{color:var(--ink)}
@media(max-width:720px){.nav ul{display:none}}

/* ===== hero ===== */
.hero{position:relative;overflow:hidden;border-bottom:1px solid var(--rule)}
#flowfield{position:absolute;inset:0;width:100%;height:100%;z-index:0;opacity:.5}
.hero .page{position:relative;z-index:1;padding-top:64px;padding-bottom:40px}
.eyebrow{display:inline-flex;align-items:center;gap:10px;color:var(--muted)}
.eyebrow .bip{width:7px;height:7px;border-radius:50%;background:var(--accent);
  box-shadow:0 0 0 3px color-mix(in oklab, var(--accent) 30%, transparent);
  animation:pulse 2.2s ease-in-out infinite}
@keyframes pulse{0%,100%{transform:scale(1);opacity:1}50%{transform:scale(1.25);opacity:.7}}

h1.title{
  font-family:'Playfair Display',Georgia,serif;font-weight:700;
  font-size:clamp(46px,7vw,92px);line-height:0.98;letter-spacing:-0.015em;
  margin:18px 0 0;text-wrap:balance;
}
.subtitle{
  font-family:'Playfair Display',Georgia,serif;font-weight:400;font-style:italic;
  font-size:clamp(18px,2.4vw,26px);line-height:1.25;color:var(--ink-2);
  margin:14px 0 0;max-width:30ch;
}
.authors{margin-top:26px;font-size:16px;line-height:1.6;color:var(--ink)}
.authors a{border-bottom:1px solid var(--rule);transition:border-color .15s}
.authors a:hover{border-color:var(--ink)}
.authors sup{font-size:10px;color:var(--muted)}
.affils{margin-top:8px;color:var(--muted);font-size:13px;line-height:1.6}

/* button row */
.btnrow{display:flex;flex-wrap:wrap;gap:12px;margin-top:28px}
.btn{
  display:inline-flex;align-items:center;gap:9px;
  font-size:13.5px;font-weight:500;padding:10px 16px;border-radius:999px;
  border:1px solid var(--ink);color:var(--ink);transition:background .2s,color .2s;
}
.btn:hover{background:var(--ink);color:var(--paper)}
.btn .ic{font-size:14px}
.btn.soon{border-color:var(--rule);color:var(--muted);cursor:default}
.btn.soon:hover{background:transparent;color:var(--muted)}
.btn.soon .tag{font-family:'JetBrains Mono',monospace;font-size:9px;letter-spacing:.06em;
  text-transform:uppercase;border:1px solid var(--rule);border-radius:5px;padding:1px 5px;margin-left:2px}

/* ===== hero video ===== */
.herovid{margin-top:40px}
.frame{position:relative;border:1px solid var(--rule);border-radius:14px;overflow:hidden;
  background:#000;box-shadow:0 30px 60px -30px rgba(18,18,18,.35)}
.frame video{display:block;width:100%;height:auto}
.divider-mid{position:absolute;top:0;bottom:0;left:50%;width:1px;background:rgba(255,255,255,.35);z-index:2}
.vid-cap{margin-top:14px;color:var(--ink-2);font-size:14.5px;line-height:1.6;max-width:80ch}
.vid-cap b{font-weight:600}

/* ===== generic section ===== */
.block{padding:72px 0;border-bottom:1px solid var(--rule-2)}
.sec-head{display:flex;align-items:baseline;gap:14px;margin-bottom:8px}
.sec-head .num{font-family:'JetBrains Mono',monospace;font-size:12px;color:var(--accent);letter-spacing:.1em}
.sec-head h2{font-family:'Playfair Display',Georgia,serif;font-weight:700;
  font-size:clamp(26px,3.4vw,40px);letter-spacing:-0.01em;margin:0}
.lead{font-size:18px;line-height:1.65;color:var(--ink-2);max-width:68ch;margin:0 0 4px}
.lead b{font-weight:600;color:var(--ink)}

/* key-idea chips */
.chips{display:flex;flex-wrap:wrap;gap:12px;margin-top:26px}
.chip{display:flex;flex-direction:column;gap:4px;border:1px solid var(--rule);border-radius:12px;
  padding:16px 18px;min-width:200px;flex:1;background:var(--paper-2)}
.chip .k{font-family:'JetBrains Mono',monospace;font-size:10px;letter-spacing:.08em;
  text-transform:uppercase;color:var(--accent)}
.chip .v{font-size:15px;font-weight:500;line-height:1.4}
.chip .d{font-size:13px;color:var(--muted);line-height:1.5}

/* method figures */
.figwrap{margin-top:32px;border:1px solid var(--rule);border-radius:14px;overflow:hidden;background:#fff}
.figwrap img{width:100%}
.figcap{padding:14px 18px;border-top:1px solid var(--rule-2);font-size:13.5px;color:var(--muted);line-height:1.6}
.figcap b{color:var(--ink-2);font-weight:600}
.fig-2col{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin-top:32px}
@media(max-width:820px){.fig-2col{grid-template-columns:1fr}}

/* ===== claims (results) ===== */
.claims{display:flex;flex-direction:column;gap:56px;margin-top:40px}
.claim{display:grid;grid-template-columns:0.85fr 1.15fr;gap:40px;align-items:center}
@media(max-width:860px){
  .claim{grid-template-columns:1fr}
}
.claim-num{font-family:'JetBrains Mono',monospace;font-size:12px;color:var(--accent);letter-spacing:.1em}
.claim h3{font-family:'Playfair Display',Georgia,serif;font-weight:700;font-size:clamp(22px,2.6vw,30px);
  line-height:1.12;letter-spacing:-0.01em;margin:10px 0 12px}
.claim p{font-size:15.5px;line-height:1.65;color:var(--ink-2);margin:0;max-width:46ch}
.claim .media{border:1px solid var(--rule);border-radius:12px;overflow:hidden;background:#fff}
.claim .media img,.claim .media video{width:100%;display:block}
.claim .media .cap{padding:10px 14px;border-top:1px solid var(--rule-2);font-size:12px;color:var(--muted);font-family:'JetBrains Mono',monospace;letter-spacing:.03em}

/* ===== overview video (secondary) ===== */
.overview-wrap{margin-top:8px;width:80%;margin-left:auto;margin-right:auto}
@media(max-width:820px){.overview-wrap{width:100%}}

/* ===== bibtex ===== */
.bibcard{position:relative;background:var(--ink);color:#e9e6df;border-radius:14px;
  padding:22px 22px 20px;margin-top:24px;overflow:auto}
.bibcard pre{margin:0;font-family:'JetBrains Mono',monospace;font-size:12.5px;line-height:1.7;
  white-space:pre;color:#e9e6df}
.copybtn{position:absolute;top:14px;right:14px;font-family:'JetBrains Mono',monospace;font-size:10px;
  letter-spacing:.06em;text-transform:uppercase;color:var(--paper);background:rgba(255,255,255,.1);
  border:1px solid rgba(255,255,255,.2);border-radius:7px;padding:6px 10px;cursor:pointer;transition:background .15s}
.copybtn:hover{background:rgba(255,255,255,.2)}

/* ===== footer ===== */
footer.foot{padding:48px 0 64px}
.foot-grid{display:flex;justify-content:space-between;flex-wrap:wrap;gap:24px;align-items:flex-end}
.foot a{border-bottom:1px solid var(--rule);transition:border-color .15s}
.foot a:hover{border-color:var(--ink)}
.foot .muted{color:var(--muted);font-size:13px;line-height:1.7}