/* ============================================================
   Ultradian — Research surface (shared)
   The restrained end of the Ultradian dark-editorial brand.
   Tokens reused verbatim from ../index.html :root.
   Used by:  /research/            (index)
             /research/<slug>/     (per-paper on-ramp)
   ============================================================ */

*{margin:0;padding:0;box-sizing:border-box}

:root{
  --bg:#060807;
  --sur:#0b0e0c;
  --s2:#101412;
  --ghost:rgba(255,255,255,.06);
  --ghost2:rgba(255,255,255,.09);
  --tx:rgba(237,240,238,.90);
  --t2:rgba(237,240,238,.50);
  --t3:rgba(237,240,238,.28);
  --ac:#4a8c6a;
  --a2:#6aad88;
  --a3:#8ac4a2;
  --acg:linear-gradient(135deg,#4a8c6a,#6aad88);
  --acsoft:rgba(74,140,106,.07);
  --acline:rgba(74,140,106,.25);
  --chrome:'IBM Plex Sans',system-ui,-apple-system,sans-serif;
  --prose:'IBM Plex Serif',Georgia,serif;
  --mono:'IBM Plex Mono','SF Mono','Fira Code',monospace;
}

html{
  font-family:var(--chrome);
  background:var(--bg);
  color:var(--tx);
  -webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;
  text-rendering:optimizeLegibility;
}
body{min-height:100vh;overflow-x:hidden;line-height:1.6;position:relative}

/* Brand film grain — same fractal-noise wash as the landing page */
body::before{
  content:'';position:fixed;inset:0;opacity:.03;
  background-image:url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='.85' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  pointer-events:none;z-index:9999;
}

::selection{background:rgba(106,173,136,.22);color:rgba(237,240,238,.97)}

a{color:var(--a2);text-decoration:none;transition:color .15s ease}
a:hover{color:var(--a3)}
a:focus-visible{outline:1.5px solid var(--ac);outline-offset:3px;border-radius:3px}

.skip{position:absolute;left:-9999px;top:auto;width:1px;height:1px;overflow:hidden}
.skip:focus{left:16px;top:12px;width:auto;height:auto;padding:8px 14px;background:var(--sur);border:1px solid var(--acline);border-radius:6px;z-index:10;color:var(--tx)}

/* ---------- shared reading column ---------- */
.wrap{max-width:840px;margin:0 auto;padding:0 24px;position:relative;z-index:1}

/* ---------- masthead ---------- */
.masthead{padding:34px 0 0}
.masthead .wrap{display:flex;align-items:center;justify-content:space-between;gap:16px}
.mark-brand{
  font-family:var(--prose);
  font-size:17px;font-weight:400;font-style:italic;
  color:var(--a2);letter-spacing:-.01em;
  display:inline-flex;align-items:center;gap:12px;
}
.mark-brand::before{content:'';width:24px;height:1.5px;background:var(--ac)}
.mark-brand:hover{color:var(--a3)}
.mast-nav{
  font-family:var(--chrome);font-size:12px;font-weight:500;
  letter-spacing:.08em;text-transform:uppercase;color:var(--t2);
}

/* ---------- back link (on-ramp) ---------- */
.backlink{
  display:inline-flex;align-items:center;gap:7px;
  font-family:var(--chrome);font-size:12.5px;font-weight:500;
  letter-spacing:.03em;color:var(--t2);
}
.backlink:hover{color:var(--a2)}
.backlink svg{transition:transform .2s}
.backlink:hover svg{transform:translateX(-3px)}

/* ---------- index hero (one-sentence mission) ---------- */
.res-hero{padding:76px 0 30px}
.res-eyebrow{
  font-family:var(--chrome);font-size:11px;font-weight:600;
  letter-spacing:.24em;text-transform:uppercase;color:var(--ac);
  margin-bottom:26px;
}
.res-mission{
  font-family:var(--prose);
  font-size:clamp(21px,3.1vw,29px);
  font-weight:300;line-height:1.42;letter-spacing:-.015em;
  color:rgba(237,240,238,.94);
  max-width:620px;
}
.res-mission em{font-style:italic;color:var(--a2)}

/* ---------- divider ---------- */
.rule{height:1px;background:linear-gradient(90deg,var(--acline) 0%,var(--ghost) 40%,transparent 100%);margin:14px 0 4px}

/* ---------- card list (index) ---------- */
.papers{padding:22px 0 90px}
.papers-label{
  font-family:var(--chrome);font-size:11px;font-weight:600;
  letter-spacing:.18em;text-transform:uppercase;color:var(--t3);
  margin:0 0 8px;
}
.paper-card{
  display:grid;
  grid-template-columns:88px 1fr;
  gap:26px;align-items:start;
  padding:30px 4px;
  border-top:1px solid var(--ghost);
  transition:border-color .3s;
}
.paper-card:hover{border-color:var(--acline)}
.paper-illo{width:88px;height:64px;border-radius:9px;overflow:hidden;background:var(--sur);box-shadow:inset 0 0 0 1px var(--ghost)}
.paper-illo svg{display:block;width:100%;height:100%}

.paper-tag{
  font-family:var(--mono);font-size:11px;font-weight:400;
  letter-spacing:.04em;color:var(--a2);
  display:inline-block;margin-bottom:11px;
}
.paper-title{
  font-family:var(--prose);
  font-size:clamp(19px,2.5vw,23px);
  font-weight:400;line-height:1.32;letter-spacing:-.01em;
  color:rgba(237,240,238,.95);
  margin-bottom:12px;
}
.paper-card:hover .paper-title{color:var(--a3)}
.paper-title a{color:inherit}
.paper-title a:hover{color:var(--a3)}
.paper-date{
  font-family:var(--mono);font-size:11.5px;
  letter-spacing:.03em;color:var(--t3);
}

/* ---------- on-ramp page ---------- */
.onramp{padding:52px 0 30px}
.onramp-illo{
  width:100%;max-width:360px;height:160px;border-radius:12px;overflow:hidden;
  background:var(--sur);box-shadow:inset 0 0 0 1px var(--ghost);margin-bottom:34px;
}
.onramp-illo svg{display:block;width:100%;height:100%}
.onramp-tag{
  font-family:var(--mono);font-size:12px;letter-spacing:.05em;
  color:var(--a2);display:block;margin-bottom:16px;
}
.onramp-title{
  font-family:var(--prose);
  font-size:clamp(27px,4.2vw,40px);
  font-weight:300;line-height:1.16;letter-spacing:-.025em;
  color:rgba(237,240,238,.97);
  margin-bottom:16px;
}
.onramp-date{
  font-family:var(--mono);font-size:12px;letter-spacing:.03em;
  color:var(--t3);
}

.lede{
  font-family:var(--prose);
  font-size:clamp(17px,2.1vw,19.5px);
  font-weight:400;line-height:1.72;
  color:rgba(237,240,238,.88);
  margin:40px 0;
}
.lede em{font-style:italic;color:var(--a3)}

/* ---------- credibility block ---------- */
.cred{
  background:var(--sur);
  box-shadow:inset 0 0 0 1px var(--ghost2);
  border-radius:14px;
  padding:28px 30px;
  margin:8px 0 40px;
  position:relative;overflow:hidden;
}
.cred::before{content:'';position:absolute;top:0;left:0;right:0;height:1px;background:linear-gradient(90deg,transparent 5%,var(--acline) 50%,transparent 95%)}
.cred-label{
  font-family:var(--chrome);font-size:10px;font-weight:600;
  letter-spacing:.22em;text-transform:uppercase;color:var(--ac);
  margin-bottom:18px;
}
.cred-list{list-style:none;display:flex;flex-direction:column;gap:15px}
.cred-list li{
  display:grid;grid-template-columns:16px 1fr;gap:12px;align-items:start;
  font-family:var(--prose);font-size:15.5px;line-height:1.6;color:var(--t2);
}
.cred-list li strong{color:rgba(237,240,238,.9);font-weight:500}
.cred-mark{margin-top:7px;width:6px;height:6px;border-radius:50%;background:var(--a2);box-shadow:0 0 8px rgba(106,173,136,.5)}

/* ---------- CTAs ---------- */
.cta-row{display:flex;flex-wrap:wrap;align-items:center;gap:14px 22px;margin:6px 0 8px}
.btn-read{
  display:inline-flex;align-items:center;gap:9px;
  font-family:var(--chrome);font-size:14px;font-weight:600;letter-spacing:.01em;
  color:var(--bg);background:var(--acg);
  padding:12px 26px;border-radius:10px;
  transition:transform .2s,box-shadow .2s;
}
.btn-read:hover{transform:translateY(-1px);box-shadow:0 4px 20px rgba(74,140,106,.3);color:var(--bg)}
.btn-read svg{transition:transform .2s}
.btn-read:hover svg{transform:translateX(3px)}
.pdf-link{
  font-family:var(--chrome);font-size:13px;font-weight:500;
  letter-spacing:.02em;color:var(--t2);
}
.pdf-link:hover{color:var(--a2)}

/* ---------- grounds line ---------- */
.grounds{
  font-family:var(--prose);font-size:15px;font-style:italic;line-height:1.6;
  color:var(--t2);
  padding:24px 0 0;margin-top:34px;border-top:1px solid var(--ghost);
}
.grounds a{font-style:normal}

/* ---------- footer ---------- */
.res-foot{
  padding:40px 0 60px;margin-top:40px;
  border-top:1px solid var(--ghost);
}
.res-foot .wrap{
  display:flex;flex-wrap:wrap;justify-content:space-between;gap:12px;
  font-family:var(--chrome);font-size:12px;letter-spacing:.06em;
  text-transform:uppercase;color:var(--t3);
}
.res-foot a{color:var(--t2)}
.res-foot a:hover{color:var(--a2)}

/* ---------- responsive ---------- */
@media(max-width:540px){
  .wrap{padding:0 20px}
  .masthead{padding:26px 0 0}
  .res-hero{padding:52px 0 24px}
  .paper-card{grid-template-columns:1fr;gap:16px;padding:26px 2px}
  .paper-illo{width:96px;height:68px}
  .onramp-illo{height:132px}
  .cred{padding:24px 22px}
  .res-foot .wrap{flex-direction:column;gap:8px}
}

@media(prefers-reduced-motion:reduce){
  *,*::before,*::after{transition-duration:.001ms !important;animation-duration:.001ms !important}
}