/* Stochastic Series Lab — house stylesheet. Static and self-contained. */
:root{
  --bone:#F7F5F0;
  --ink:#20242E;
  --emerald:#0E5C4A;
  --purple:#7A3E9D;
  --rule:#E3DFD7;
  --card:#FFFFFF;
  --muted:#6A6F7A;
  --head:"Century Schoolbook","Century Schoolbook L",Georgia,serif;
  --body:"Optima","Segoe UI",Tahoma,sans-serif;
  --data:"Andale Mono","Courier New",monospace;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;background:var(--bone);color:var(--ink);
  font-family:var(--body);font-size:17px;line-height:1.62;
}
h1,h2,h3,h4{font-family:var(--head);line-height:1.24;color:var(--ink)}
h1{font-size:2.05rem;margin:0 0 .5rem}
h2{font-size:1.45rem;margin:2.1rem 0 .6rem}
h3{font-size:1.12rem;margin:1.5rem 0 .4rem}
p{margin:.65rem 0}
a{color:var(--emerald);text-decoration:none;border-bottom:1px solid rgba(14,92,74,.28)}
a:hover{color:var(--purple);border-bottom-color:var(--purple)}
.mono{font-family:var(--data);font-size:.82rem}
.vh{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0 0 0 0)}

/* ---------- header ---------- */
.site-head{
  position:sticky;top:0;z-index:40;background:var(--bone);
  border-bottom:1px solid var(--rule);
}
.head-row{
  max-width:1200px;margin:0 auto;padding:.6rem 1.1rem;
  display:flex;align-items:center;gap:1rem;flex-wrap:wrap;
}
.brand{display:flex;align-items:center;gap:.6rem;border:0}
.brand .mark{width:40px;height:40px;flex:0 0 auto}
.wordmark{display:flex;flex-direction:column;line-height:1.05}
.wordmark .pub{font-family:var(--data);letter-spacing:.14em;font-size:.86rem;color:var(--ink)}
.wordmark .dom{font-family:var(--data);font-size:.66rem;color:var(--muted);letter-spacing:.04em}
.head-spacer{flex:1 1 auto}

/* ---------- state rail (wide display) ---------- */
.state-rail{display:flex;align-items:center;gap:.15rem}
.state{position:relative}
.state>summary{
  list-style:none;cursor:pointer;display:block;
  padding:.34rem .6rem;border:1px solid var(--rule);background:var(--card);
  font-family:var(--data);font-size:.7rem;letter-spacing:.08em;color:var(--ink);
  border-radius:2px;
}
.state>summary::-webkit-details-marker{display:none}
.state>summary .nm{display:block;font-family:var(--body);font-size:.86rem;letter-spacing:0;color:var(--ink)}
.state>summary:hover{border-color:var(--emerald);color:var(--emerald)}
.state.is-active>summary{background:var(--emerald);border-color:var(--emerald);color:#fff}
.state.is-active>summary .nm{color:#fff}
.state.is-active>summary::after{
  content:"";display:inline-block;width:7px;height:7px;border-radius:50%;
  background:#fff;margin-left:6px;vertical-align:middle;box-shadow:0 0 0 2px rgba(255,255,255,.4);
}
.edge{font-family:var(--data);color:var(--purple);font-size:.85rem;padding:0 .1rem}
.state-panel{
  position:absolute;top:100%;left:0;margin-top:.35rem;min-width:230px;
  background:var(--card);border:1px solid var(--rule);border-radius:3px;
  padding:.4rem;box-shadow:0 10px 24px rgba(32,36,46,.12);
}
.state-panel a{display:block;padding:.28rem .5rem;border:0;font-size:.9rem}
.state-panel a:hover{background:var(--bone)}
.state-panel a[aria-current="page"]{color:var(--purple);font-weight:600}
.state-panel a[aria-current="page"]::before{content:"\25B8 ";color:var(--purple)}

/* ---------- mobile rail ---------- */
.mobile-rail{display:none}
.mstate{padding:.5rem 0;border-bottom:1px dotted var(--rule)}
.mstate .mtop{font-family:var(--data);font-size:.7rem;letter-spacing:.08em;color:var(--emerald)}
.mstate .mnm{font-family:var(--head);font-size:1rem}
.mstate ul{list-style:none;margin:.3rem 0 0;padding:0}
.mstate li{margin:.16rem 0}
.marrow{text-align:center;color:var(--purple);font-family:var(--data)}

/* ---------- cookie note ---------- */
.cookie-note{
  max-width:1200px;margin:0 auto;padding:.34rem 1.1rem .5rem;
  font-size:.78rem;color:var(--muted);border-top:1px dotted var(--rule);
}
.cookie-note a{border-bottom:0;text-decoration:underline}

/* ---------- main ---------- */
main{max-width:900px;margin:0 auto;padding:1.6rem 1.15rem 3rem}
article{background:transparent}
.lead{font-size:1.06rem;color:var(--muted)}
.rule{height:1px;background:var(--rule);border:0;margin:1.6rem 0}
.kicker{font-family:var(--data);font-size:.72rem;letter-spacing:.14em;color:var(--purple)}
.anchor-jump{
  display:inline-block;margin:.4rem 0 1rem;padding:.5rem 1rem;border:1px solid var(--emerald);
  color:var(--emerald);font-family:var(--data);font-size:.78rem;letter-spacing:.06em;border-radius:2px;
}
.anchor-jump:hover{background:var(--emerald);color:#fff;border-color:var(--emerald)}
.callout{background:var(--card);border:1px solid var(--rule);border-left:3px solid var(--purple);
  padding:.7rem 1rem;margin:1.1rem 0;border-radius:2px}
.callout h3{margin-top:.1rem}
.note{font-size:.88rem;color:var(--muted)}

/* figures / vectors */
figure{margin:1.3rem 0;background:var(--card);border:1px solid var(--rule);border-radius:3px;padding:.7rem}
figure svg{display:block;width:100%;height:auto}
figcaption{font-family:var(--data);font-size:.74rem;color:var(--muted);margin-top:.5rem}
.photo{display:block;width:100%;height:auto;border:1px solid var(--rule);border-radius:2px}
.pair{display:flex;gap:.8rem;flex-wrap:wrap}
.pair figure{flex:1 1 260px}

/* icons for nav labels */
.ic{width:15px;height:15px;vertical-align:-2px;margin-right:.4rem}

/* lists */
ul.tight{margin:.5rem 0;padding-left:1.1rem}
ul.tight li{margin:.22rem 0}
dl.terms dt{font-family:var(--head);margin-top:.8rem}
dl.terms dd{margin:.15rem 0 0}

/* ---------- footer: transition matrix ---------- */
.site-foot{border-top:1px solid var(--rule);background:var(--card);margin-top:2rem}
.foot-wrap{max-width:1200px;margin:0 auto;padding:1.6rem 1.15rem 2rem}
.matrix-title{font-family:var(--data);font-size:.76rem;letter-spacing:.12em;color:var(--purple);margin:0 0 .55rem}
.matrix{display:grid;grid-template-columns:repeat(5,1fr);gap:.55rem}
.mcell{border:1px solid var(--rule);border-radius:2px;padding:.5rem;background:var(--bone)}
.mcell h4{margin:0 0 .3rem;font-family:var(--data);font-size:.7rem;letter-spacing:.06em;color:var(--emerald)}
.mcell h4 span{display:block;font-family:var(--body);font-size:.9rem;color:var(--ink)}
.mcell a{display:block;font-size:.82rem;padding:.1rem 0;border:0}
.foot-meta{display:grid;grid-template-columns:1fr 1fr;gap:1.2rem;margin-top:1.3rem}
.foot-meta h4{margin:0 0 .35rem;font-family:var(--data);font-size:.74rem;letter-spacing:.08em;color:var(--purple)}
.foot-meta p{font-size:.86rem;color:var(--muted)}
.foot-legal{margin:1.2rem 0 .5rem;font-size:.8rem;color:var(--muted)}
.disclaimer{background:var(--bone);border:1px dashed var(--rule);border-radius:2px;padding:.6rem .8rem;
  font-size:.8rem;color:var(--muted)}
.copy{font-family:var(--data);font-size:.72rem;color:var(--muted);margin:.7rem 0 0}

/* ---------- form ---------- */
form.ask{background:var(--card);border:1px solid var(--rule);border-radius:3px;padding:1rem;max-width:640px}
form.ask label{display:block;font-family:var(--data);font-size:.74rem;letter-spacing:.05em;margin:.7rem 0 .2rem;color:var(--ink)}
form.ask input[type=text],form.ask input[type=email],form.ask textarea{
  width:100%;padding:.5rem;border:1px solid var(--rule);background:var(--bone);
  font-family:var(--body);font-size:.95rem;color:var(--ink);border-radius:2px;
}
form.ask textarea{min-height:130px}
form.ask .consent{display:flex;gap:.5rem;align-items:flex-start;margin:1rem 0}
form.ask .consent label{margin:0;font-family:var(--body);font-size:.88rem;letter-spacing:0}
form.ask button{
  margin-top:.6rem;padding:.55rem 1.3rem;border:1px solid var(--emerald);background:var(--emerald);
  color:#fff;font-family:var(--data);font-size:.78rem;letter-spacing:.08em;border-radius:2px;cursor:pointer;
}
form.ask button:hover{background:var(--purple);border-color:var(--purple)}

@media (max-width:760px){
  .head-row{padding:.55rem .8rem}
  .state-rail{display:none}
  .mobile-rail{
    display:block;max-width:1200px;margin:0 auto;padding:.4rem .9rem .2rem;
    border-top:1px solid var(--rule);
  }
  .wordmark .pub{font-size:.78rem}
  main{padding:1.1rem .85rem 2.4rem}
  .matrix{grid-template-columns:1fr}
  .foot-meta{grid-template-columns:1fr}
}