/* ============================================================
   From Individual Learning to Market Equilibrium — project page.
   Restrained academic aesthetic. Pure CSS, no dependencies.
   ============================================================ */

:root{
  /* planes — warm paper */
  --bg:        #f6f2e8;
  --bg-2:      #efe9dc;
  --surface:   #fffdf7;
  --surface-2: #f1ece0;
  --surface-3: #e8e2d3;
  --line:      rgba(58,46,28,.16);
  --line-2:    rgba(58,46,28,.28);

  /* ink */
  --ink:   #2b261f;
  --ink-2: #5b544a;
  --muted: #8b8173;

  /* one restrained accent + one colour per simulation variant */
  --accent:  #2c6e7f;      /* deep teal */
  --both:    #3f7a4e;      /* both corrections — the competitive equilibrium */
  --neither: #c0392b;      /* naive RL — both biases present */
  --struct:  #b5762e;      /* structural correction only (mean field, uncalibrated cost) */
  --param:   #7d3c98;      /* parametric correction only (c_eff, still a manipulator) */
  --theory:  #2b261f;      /* analytical benchmark */

  --radius: 12px;
  --radius-sm: 9px;
  --maxw: 1140px;
  --measure: 760px;
  --shadow: 0 10px 30px -22px rgba(60,42,18,.5);

  --sans: system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --serif: Georgia, "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

*{ box-sizing:border-box; }
html{ scroll-behavior:smooth; scroll-padding-top:70px; }
body{
  margin:0; font-family:var(--sans); color:var(--ink); background:var(--bg);
  line-height:1.68; font-size:16px;
  -webkit-font-smoothing:antialiased; text-rendering:optimizeLegibility; overflow-x:hidden;
}
img,svg,canvas{ max-width:100%; }
img{ display:block; }
a{ color:var(--accent); text-decoration:none; }
a:hover{ text-decoration:underline; }
::selection{ background:rgba(44,110,127,.16); color:var(--accent); }

/* ---------- layout ---------- */
.wrap{ max-width:var(--maxw); margin:0 auto; padding:0 24px; }
section{ padding:64px 0; position:relative; border-top:1px solid var(--line); }
.section-tag{
  display:block; font:600 12px/1 var(--mono); letter-spacing:.2em; text-transform:uppercase;
  color:var(--accent); margin-bottom:14px;
}
h1,h2,h3{ font-family:var(--serif); line-height:1.2; letter-spacing:-.005em; margin:0 0 .5em; font-weight:700; }
h2{ font-size:clamp(25px,3.4vw,36px); }
h3{ font-size:clamp(18px,2.1vw,22px); }
h2 em, h1 em{ font-style:italic; color:var(--ink); }
.lead{ font-size:clamp(16px,1.5vw,18px); color:var(--ink-2); max-width:var(--measure); }
.lead b{ color:var(--ink); font-weight:600; }
.muted{ color:var(--muted); }
.mono{ font-family:var(--mono); }

/* ---------- nav ---------- */
.nav{
  position:sticky; top:0; z-index:100;
  backdrop-filter:blur(10px); background:rgba(246,242,232,.86);
  border-bottom:1px solid var(--line);
}
.nav .wrap{ display:flex; align-items:center; gap:20px; height:58px; }
.brand{ display:flex; align-items:center; gap:9px; font-family:var(--serif); font-weight:700;
  color:var(--ink); font-size:18px; }
.brand:hover{ text-decoration:none; }
.brand .logo{ width:16px; height:16px; border-radius:3px; background:var(--accent); }
.nav-links{ display:flex; gap:2px; margin-left:auto; }
.nav-links a{ color:var(--ink-2); font-size:14px; font-weight:500; padding:7px 11px; border-radius:7px; }
.nav-links a:hover{ color:var(--ink); background:var(--surface-2); text-decoration:none; }
.nav-links a.active{ color:var(--accent); }
.nav-burger{ display:none; margin-left:auto; background:none; border:0; color:var(--ink); font-size:22px; cursor:pointer; }

/* ---------- hero ---------- */
.hero{ padding:56px 0 52px; text-align:center; border-top:0; }
.hero-inner{ max-width:900px; margin:0 auto; }
.venue{ font:600 12.5px/1 var(--mono); letter-spacing:.18em; text-transform:uppercase;
  color:var(--accent); margin:0 0 22px; }
.paper-title{ font-family:var(--serif); font-size:clamp(25px,3.4vw,36px); line-height:1.18;
  color:var(--ink); margin:0 auto 20px; letter-spacing:-.012em; max-width:28ch; text-wrap:balance; }

.authors{ display:flex; gap:34px; justify-content:center; flex-wrap:wrap; margin:0 0 24px; }
.authors .au{ font-size:15px; }
.authors .au .n{ font-weight:600; color:var(--ink); }
.authors .au .aff{ font-size:13px; color:var(--muted); line-height:1.5; }
.authors .au .tag{ font:600 10px/1 var(--mono); letter-spacing:.1em; text-transform:uppercase;
  color:var(--accent); }

.abstract{ max-width:var(--measure); margin:0 auto 24px; color:var(--ink-2); font-size:16.5px; text-align:left; }
.abstract b{ color:var(--ink); font-weight:600; }
.abstract .lbl{ font:600 11.5px/1 var(--mono); letter-spacing:.18em; text-transform:uppercase;
  color:var(--accent); display:block; margin-bottom:10px; }

.hero-links{ display:flex; gap:10px; justify-content:center; flex-wrap:wrap; margin-bottom:32px; }
.hero-links a{ display:inline-flex; align-items:center; gap:7px; font-size:14px; font-weight:600;
  color:var(--ink); border:1px solid var(--line-2); background:var(--surface);
  border-radius:8px; padding:9px 15px; transition:background .15s; }
.hero-links a:hover{ background:var(--surface-2); text-decoration:none; }
.hero-links a.primary{ border-color:var(--accent); color:var(--accent); }
.hero-links a .ic{ font-family:var(--mono); color:var(--accent); font-size:12.5px; }

/* ---------- highlights strip ---------- */
.highlights{ display:flex; flex-wrap:wrap; margin-top:8px;
  border-top:1px solid var(--line); border-bottom:1px solid var(--line); }
.highlights .h{ flex:1 1 190px; text-align:center; padding:18px 14px; border-left:1px solid var(--line); }
.highlights .h:first-child{ border-left:0; }
.highlights .h b{ display:block; font-family:var(--serif); font-size:26px; font-weight:700; color:var(--ink); }
.highlights .h b small{ font-size:.55em; color:var(--ink-2); font-weight:400; }
.highlights .h span{ font-size:12.5px; color:var(--muted); }

/* ---------- cards / grids ---------- */
.card{ background:var(--surface); border:1px solid var(--line); border-radius:var(--radius); padding:24px; }
.card h3{ margin-top:0; }
.card p{ color:var(--ink-2); font-size:14.5px; }
.card p:last-child{ margin-bottom:0; }
.kicker{ font:600 11.5px/1 var(--mono); letter-spacing:.13em; text-transform:uppercase;
  color:var(--muted); margin:0 0 10px; }
.grid{ display:grid; gap:20px; }
.g2{ grid-template-columns:repeat(2,1fr); }
.g3{ grid-template-columns:repeat(3,1fr); }

figure.fig{ margin:0; background:var(--surface); border:1px solid var(--line); border-radius:var(--radius);
  padding:16px; }
figure.fig > svg{ display:block; width:100%; height:auto; }
figure.fig img{ width:100%; height:auto; border-radius:4px; }
figure.fig figcaption{ color:var(--ink-2); font-size:13.5px; padding:14px 4px 2px; line-height:1.55;
  font-style:italic; border-top:1px solid var(--line); margin-top:12px; }
figure.fig figcaption b{ color:var(--ink); font-style:normal; }

/* ---------- inline math variables ----------
   Set explicitly rather than left to the browser defaults: line-height:0
   keeps sub/sup from opening up the leading, and the trailing margin stops
   an italic descender colliding with the next word.                     */
sub, sup{ font-size:.7em; line-height:0; position:relative; vertical-align:baseline; }
sub{ bottom:-.28em; }
sup{ top:-.48em; }
sup sub, sub sub, sup sup{ font-size:.85em; }
i sub, i sup, em sub, em sup, .mv sub, .mv sup{ margin-right:.14em; }
.mv{ font-style:italic; }
.mv sub, .mv sup{ font-style:normal; }
h2 em sub{ margin-right:.1em; }

/* ---------- equations ---------- */
.eq{ background:var(--surface-2); border:1px solid var(--line); border-radius:var(--radius-sm);
  padding:14px 20px; margin:18px 0; overflow-x:auto; }
.eq math{ font-size:1.24em; color:var(--ink); }
.eq.inline{ padding:12px 16px; margin:14px 0 0; }
.eq.inline math{ font-size:1.05em; }
.eq-note{ color:var(--muted); font-size:13px; margin-top:8px; line-height:1.5; font-style:italic; }
.eq-num{ float:right; color:var(--muted); font:500 12px var(--mono); }
.eq.hero-eq{ background:var(--surface); border-color:var(--line-2); }

/* chips */
.chips{ display:flex; flex-wrap:wrap; gap:8px; }
.chip{ font:500 12.5px/1 var(--mono); color:var(--ink-2); border:1px solid var(--line);
  background:var(--surface); border-radius:7px; padding:7px 11px; }

/* ---------- interactive panels ---------- */
.lab{ background:var(--surface); border:1px solid var(--line-2); border-radius:var(--radius); padding:24px; }
.lab-head{ display:flex; align-items:baseline; gap:12px; margin-bottom:6px; flex-wrap:wrap; }
.lab-head .k{ font:600 11.5px/1 var(--mono); letter-spacing:.16em; text-transform:uppercase; color:var(--accent); }
.lab-head h3{ font-size:19px; margin:0; }
.control{ margin:13px 0; }
.control label{ display:flex; justify-content:space-between; gap:12px; font-size:13.5px; color:var(--ink-2);
  margin-bottom:6px; font-weight:500; }
.control label b{ color:var(--ink); font-family:var(--mono); font-weight:600; }
.control .hint{ font-size:12.5px; color:var(--muted); margin:5px 0 0; line-height:1.5; }
input[type=range]{ -webkit-appearance:none; appearance:none; width:100%; height:5px; border-radius:5px;
  background:var(--surface-3); outline:none; cursor:pointer; }
input[type=range]::-webkit-slider-thumb{ -webkit-appearance:none; width:17px; height:17px; border-radius:50%;
  background:var(--accent); border:2px solid var(--surface); box-shadow:0 0 0 1px var(--line-2); cursor:pointer; }
input[type=range]::-moz-range-thumb{ width:15px;height:15px;border-radius:50%;background:var(--accent);
  border:2px solid var(--surface); cursor:pointer; }

.readout{ display:flex; gap:22px; flex-wrap:wrap; margin-top:6px; }
.readout .r .v{ font-family:var(--serif); font-weight:700; font-size:23px; line-height:1.15; color:var(--ink); }
.readout .r .l{ font-size:12px; color:var(--muted); margin-top:2px; }

.seg{ display:inline-flex; border:1px solid var(--line-2); border-radius:8px; overflow:hidden;
  background:var(--surface-2); flex-wrap:wrap; }
.seg button{ font:600 12px/1 var(--mono); letter-spacing:.1em; text-transform:uppercase;
  padding:9px 15px; border:0; background:transparent; color:var(--ink-2); cursor:pointer; transition:.12s; }
.seg button + button{ border-left:1px solid var(--line-2); }
.seg button:hover{ color:var(--ink); background:var(--surface-3); }
.seg button.on{ background:var(--accent); color:#fdf6ec; }
.seg.right{ margin-left:auto; }

/* ---------- the 2x2 correction grid ---------- */
.quad{ display:grid; grid-template-columns:auto 1fr 1fr; gap:12px; align-items:stretch; margin-top:18px; }
.quad .lab-y{ writing-mode:vertical-rl; transform:rotate(180deg); display:flex; align-items:center;
  justify-content:center; font:600 11px/1 var(--mono); letter-spacing:.14em; text-transform:uppercase;
  color:var(--muted); padding:0 2px; }
.quad .hdr{ font:600 11px/1.5 var(--mono); letter-spacing:.12em; text-transform:uppercase;
  color:var(--muted); text-align:center; padding-bottom:2px; }
.cell{ border:1px solid var(--line-2); border-top:3px solid var(--c); border-radius:var(--radius-sm);
  background:var(--surface); padding:16px 16px 14px; min-width:0; }
.cell .nm{ font:600 11px/1 var(--mono); letter-spacing:.1em; text-transform:uppercase; color:var(--c); }
.cell .th{ font-family:var(--serif); font-weight:700; font-size:34px; line-height:1.1; color:var(--ink);
  margin:8px 0 0; }
.cell .th small{ font-size:.42em; color:var(--muted); font-weight:400; font-family:var(--mono); }
.cell .gap{ font:600 12.5px var(--mono); color:var(--c); margin-top:2px; }
.cell .d{ font-size:13px; color:var(--ink-2); line-height:1.5; margin:10px 0 0; }
.cell .bar{ height:6px; border-radius:3px; background:var(--surface-3); margin-top:12px; position:relative; overflow:hidden; }
.cell .bar i{ position:absolute; top:0; bottom:0; left:0; background:var(--c); border-radius:3px; }
.cell .bar u{ position:absolute; top:-3px; bottom:-3px; width:2px; background:var(--theory); }
.cell.win{ box-shadow:var(--shadow); }

/* ---------- charts ---------- */
.chart{ width:100%; height:auto; display:block; }
.chart text{ font-family:var(--sans); }
.tick{ fill:var(--muted); font-size:11px; }
.axis-line{ stroke:var(--line-2); stroke-width:1; fill:none; }
.grid-line{ stroke:var(--line); stroke-width:1; }
.ser{ fill:none; stroke-width:1.9; stroke-linejoin:round; stroke-linecap:round; }
.axlab{ fill:var(--ink-2); font-size:11.5px; font-weight:600; }
.tooltip{ position:fixed; z-index:200; pointer-events:none; background:#2b261f; color:#fbf5ea;
  border:1px solid rgba(0,0,0,.2); border-radius:8px; padding:8px 11px; font-size:12.5px;
  box-shadow:0 10px 22px rgba(60,42,18,.3); opacity:0; transition:opacity .12s; max-width:260px; }
.tooltip .tt-t{ font-weight:700; margin-bottom:3px; }
.tooltip .tt-r{ color:#d8cfbd; font-family:var(--mono); font-size:12px; }
.legend{ display:flex; gap:18px; flex-wrap:wrap; margin-top:14px; }
.legend .li{ display:flex; align-items:center; gap:7px; font-size:13px; color:var(--ink-2); }
.legend .li .sw{ width:16px; height:3px; border-radius:2px; }
.legend .li .dash{ width:16px; height:0; border-top:2px dashed currentColor; }

/* ---------- tables ---------- */
table.tbl{ width:100%; border-collapse:collapse; font-size:14px; }
table.tbl th, table.tbl td{ padding:8px 12px; border-bottom:1px solid var(--line); text-align:left; }
table.tbl thead th{ font:600 11.5px/1.4 var(--mono); letter-spacing:.1em; text-transform:uppercase;
  color:var(--muted); border-bottom:1px solid var(--line-2); }
table.tbl td.sym{ font-family:var(--mono); color:var(--ink); width:1%; white-space:nowrap; }
table.tbl td.num{ font-family:var(--mono); text-align:right; color:var(--ink); width:1%; white-space:nowrap; }
table.tbl tbody tr:hover{ background:var(--surface-2); }
table.tbl tr.grp td{ border-bottom:1px solid var(--line-2); }

/* algorithm block — a numbered gutter plus a content column, so wrapped
   lines hang under the text rather than sliding back under the number */
.algo{ background:var(--bg-2); border:1px solid var(--line-2); border-radius:var(--radius-sm);
  padding:18px 20px 16px; font-family:var(--mono); font-size:12.5px; color:var(--ink-2); }
.algo .ttl{ font:600 11px/1 var(--mono); letter-spacing:.14em; text-transform:uppercase;
  color:var(--accent); margin-bottom:14px; }
.algo b{ color:var(--ink); font-weight:600; }

.algo ol.steps{ list-style:none; counter-reset:algo; margin:0; padding:0; }
.algo ol.steps > li{ counter-increment:algo; display:grid; grid-template-columns:18px 1fr;
  gap:0 12px; padding:3.5px 0; line-height:1.62; }
.algo ol.steps > li::before{ content:counter(algo); color:var(--muted); text-align:right;
  font-size:11px; font-variant-numeric:tabular-nums; padding-top:.2em; }
/* the loop body: indented and tied together by a rule down the left */
.algo ol.steps > li.d1 > .c{ padding-left:13px; border-left:2px solid var(--line-2); }
.algo .kw{ color:var(--accent); font-weight:600; }
.algo .mv{ font-style:italic; }
/* displayed expressions get their own line and a faint chip, so a long
   reward definition never has to share a line with prose */
.algo .expr{ display:block; margin:6px 0 3px; padding:5px 9px; font-weight:600;
  color:var(--ink); background:var(--surface); border:1px solid var(--line);
  border-radius:6px; letter-spacing:.005em; }
.algo .foot{ font-family:var(--sans); font-size:12.5px; line-height:1.6; color:var(--muted);
  margin:14px 0 0; padding-top:12px; border-top:1px solid var(--line); }
.algo .foot em{ color:var(--ink-2); font-style:normal; font-weight:600; }

/* details / callout */
details.acc{ border:1px solid var(--line); border-radius:var(--radius); background:var(--surface);
  padding:0 20px; margin-top:16px; }
details.acc summary{ cursor:pointer; padding:16px 0; font-weight:600; list-style:none;
  display:flex; align-items:center; gap:10px; }
details.acc summary::-webkit-details-marker{ display:none; }
details.acc summary::before{ content:"+"; color:var(--accent); font-family:var(--mono); font-size:19px; width:18px; }
details.acc[open] summary::before{ content:"–"; }
details.acc .body{ padding:0 0 20px; color:var(--ink-2); }
.callout{ border-left:2px solid var(--accent); padding:6px 0 6px 18px; color:var(--ink-2); }
.callout b{ color:var(--ink); }

/* bibtex */
pre.bib{ background:var(--bg-2); border:1px solid var(--line); border-radius:var(--radius-sm);
  padding:16px 18px; overflow-x:auto; font:400 12.5px/1.65 var(--mono); color:var(--ink-2); margin:0; }
pre.bib .k{ color:var(--accent); }
.bib-head{ display:flex; align-items:center; gap:12px; margin-bottom:10px; flex-wrap:wrap; }

/* misc */
.reveal{ opacity:0; transform:translateY(16px); transition:opacity .6s ease, transform .6s ease; }
.reveal.in{ opacity:1; transform:none; }
#progress{ position:fixed; top:0; left:0; height:2px; z-index:200; width:0%; background:var(--accent); opacity:.7; }
.btn{ display:inline-flex; align-items:center; gap:8px; font-weight:600; font-size:14px;
  padding:10px 18px; border-radius:8px; cursor:pointer; border:1px solid var(--line-2);
  background:var(--surface); color:var(--ink); transition:background .15s; font-family:var(--sans); }
.btn:hover{ background:var(--surface-2); text-decoration:none; }
.btn-primary{ border-color:var(--accent); color:var(--accent); }
.closing{ text-align:center; color:var(--muted); font-size:13px; padding:16px 0 8px;
  font-style:italic; line-height:1.6; }
.copyright{ text-align:center; color:var(--muted); font-size:11.5px; padding:0 0 28px;
  max-width:840px; margin:0 auto; line-height:1.6; }

/* ---------- responsive ---------- */
@media (max-width:980px){
  .g2,.g3{ grid-template-columns:1fr; }
  .nav-links{ display:none; }
  .nav-links.open{ display:flex; position:absolute; top:58px; left:0; right:0; flex-direction:column;
    background:rgba(246,242,232,.98); border-bottom:1px solid var(--line); padding:10px 16px; }
  .nav-burger{ display:block; }
  section{ padding:52px 0; }
  .seg.right{ margin-left:0; }
}
@media (max-width:700px){
  .quad{ grid-template-columns:1fr; }
  .quad .lab-y{ display:none; }
  .quad .hdr{ text-align:left; }
  .highlights .h{ flex:1 1 50%; border-left:0; border-top:1px solid var(--line); }
  .highlights .h:first-child,.highlights .h:nth-child(2){ border-top:0; }
}
@media (prefers-reduced-motion:reduce){
  *{ animation:none!important; transition:none!important; scroll-behavior:auto!important; }
  .reveal{ opacity:1; transform:none; }
}
@media print{
  .nav,#progress,.hero-links,.seg{ display:none!important; }
  .reveal{ opacity:1!important; transform:none!important; }
  body{ background:#fff; }
}