:root{
  --paper:#f7f5f0; --card:#ffffff; --card2:#fbfaf6; --rule:#e4ded2;
  --ink:#1d2422; --soft:#5d6b66; --teal:#2dd4bf; --teal-d:#0a6b5d; --sand:#b88a3e;
  --rise:#0f9e6e; --fall:#c2603f;
  --head:'Sora',system-ui,sans-serif;
  --read:'Inter',-apple-system,BlinkMacSystemFont,'Segoe UI',sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--paper);color:var(--ink);font-family:var(--read);line-height:1.68;
  -webkit-font-smoothing:antialiased;font-size:16.5px}
.shell{max-width:1020px;margin:0 auto;padding:0 22px}
a{color:var(--teal-d);text-decoration:none}
a:hover{text-decoration:underline}
h1,h2,h3{font-family:var(--head);line-height:1.18;letter-spacing:-.014em;font-weight:600}
h2{font-size:clamp(1.32rem,2.5vw,1.78rem);margin:0 0 .5em}
h3{font-size:1.08rem;margin:1.5em 0 .35em;color:#13201d}
.soft{color:var(--soft)}
section{padding:44px 0}
section + section{border-top:1px solid var(--rule)}
.eyebrow{font-family:var(--head);font-size:.72rem;letter-spacing:.2em;text-transform:uppercase;
  color:var(--teal-d);font-weight:600;margin-bottom:13px}
/* nav */
.bsw-bar{position:sticky;top:0;z-index:40;display:flex;align-items:center;justify-content:space-between;
  gap:18px;padding:13px 22px;background:rgba(247,245,240,.9);backdrop-filter:blur(8px);
  border-bottom:1px solid var(--rule)}
.bsw-sig{display:flex;align-items:center;gap:9px;font-family:var(--head);font-weight:600;color:#13201d;
  font-size:.98rem;letter-spacing:-.01em}
.bsw-sig .dot{width:11px;height:11px;border-radius:50%;background:var(--teal);box-shadow:0 0 0 3px rgba(45,212,191,.22)}
.bsw-links{display:flex;gap:21px;list-style:none;margin:0;padding:0;font-size:.9rem}
.bsw-links a{color:var(--soft)}
.bsw-links a:hover{color:var(--ink);text-decoration:none}
.bsw-go{background:var(--teal-d);color:#fff!important;padding:8px 14px;border-radius:8px;
  font-family:var(--head);font-size:.82rem;font-weight:600}
.bsw-go:hover{background:var(--teal);text-decoration:none}
.bsw-burger{display:none;background:none;border:0;cursor:pointer;width:30px;height:24px}
.bsw-burger span{display:block;height:2px;background:var(--ink);margin:5px 0;border-radius:2px}
.bsw-drawer{display:none;flex-direction:column;gap:2px;padding:8px 22px 18px;border-bottom:1px solid var(--rule);
  background:var(--card)}
.bsw-drawer a{color:var(--ink);padding:10px 0;border-bottom:1px solid var(--rule);font-size:.96rem}
.bsw-drawer.open{display:flex}
/* hero + blocks */
.bsw-top{padding:60px 0 42px}
.bsw-top h1{font-size:clamp(2rem,4.5vw,3.05rem);margin:.3em 0 .28em;color:#11201c;font-weight:700}
.stand{font-size:1.13rem;color:#37433f;max-width:64ch}
.rail{display:flex;flex-wrap:wrap;gap:10px;margin-top:24px;font-family:var(--head);font-size:.82rem}
.pill{border:1px solid var(--rule);background:var(--card);border-radius:999px;padding:7px 14px;color:var(--soft)}
.pill b{color:var(--teal-d);font-weight:600}
.act{display:inline-block;margin-top:26px;background:var(--teal-d);color:#fff;font-weight:600;
  font-family:var(--head);padding:12px 22px;border-radius:9px;font-size:.94rem}
.act:hover{background:var(--teal);text-decoration:none}
.lede{font-size:1.07rem;color:#2b3733}
.slab{background:var(--card);border:1px solid var(--rule);border-radius:14px;padding:24px 26px;margin:18px 0}
.slab.lift{border-color:#bfe9e2;box-shadow:0 14px 34px -22px rgba(15,158,140,.4)}
.lay{display:grid;gap:16px}
@media(min-width:720px){.lay3{grid-template-columns:repeat(3,1fr)}.lay2{grid-template-columns:1fr 1fr}}
.box{background:var(--card2);border:1px solid var(--rule);border-radius:12px;padding:19px}
.box h3{margin-top:0}
.mark{font-family:var(--head);font-size:.7rem;letter-spacing:.13em;text-transform:uppercase;color:var(--teal-d);font-weight:600}
ul.points{list-style:none;padding:0;margin:14px 0}
ul.points li{padding:10px 0 10px 26px;position:relative;border-bottom:1px solid var(--rule);color:#2f3b37}
ul.points li:before{content:"\2014";position:absolute;left:2px;color:var(--teal-d);font-family:var(--head)}
.spread{overflow-x:auto;margin:18px 0}
table{border-collapse:collapse;width:100%;font-size:.91rem;min-width:520px}
th,td{padding:12px 13px;border-bottom:1px solid var(--rule);text-align:left}
th{font-family:var(--head);font-size:.71rem;letter-spacing:.09em;text-transform:uppercase;color:var(--soft);font-weight:600}
tr.flagship td{background:#f0faf8}
td .up{color:var(--rise);font-family:var(--head);font-weight:600}
.trail{font-family:var(--head);font-size:.76rem;color:var(--soft);padding:18px 0 0}
.trail a{color:var(--soft)}
.trail .arr{opacity:.5;margin:0 5px}
.verd{font-size:1.1rem;color:#37433f;max-width:66ch;margin:.4em 0 0}
.prose h3{color:var(--teal-d)}
.prose code{background:#eef3f1;border:1px solid var(--rule);border-radius:5px;padding:1px 6px;font-size:.85em}
.aside{font-family:var(--head);font-size:.84rem;color:var(--soft);border-left:3px solid var(--teal);
  padding:6px 0 6px 15px;margin:18px 0;font-weight:500}
.bsw-feet{border-top:1px solid var(--rule);background:var(--card2);margin-top:32px;padding:42px 0 30px}
.bsw-feet .grid{display:grid;gap:22px}
@media(min-width:720px){.bsw-feet .grid{grid-template-columns:2fr 1fr 1fr 1fr}}
.bsw-feet a{color:var(--soft);display:block;padding:3px 0}
.bsw-feet a:hover{color:var(--teal-d)}
.bsw-feet .cap{color:#13201d;font-family:var(--head);font-size:.77rem;letter-spacing:.11em;text-transform:uppercase;margin-bottom:9px;font-weight:600}
.fine{color:#7a857f;font-size:.82rem;margin-top:24px;border-top:1px solid var(--rule);padding-top:16px}
.prose code{word-break:break-word}
.up{color:var(--rise)}
/* worked-example block: a stepped, parchment-tinted panel set apart from .aside */
.worked{background:var(--card2);border:1px solid var(--rule);border-left:4px solid var(--teal);
  border-radius:0 12px 12px 0;padding:19px 22px;margin:22px 0}
.worked .stamp{font-family:var(--head);font-size:.7rem;letter-spacing:.13em;text-transform:uppercase;
  color:var(--teal-d);font-weight:600;margin-bottom:10px}
.worked ol{margin:0;padding-left:20px}
.worked ol li{padding:7px 0;color:#2f3b37}
.worked ol li b{color:#13201d}
.worked code{background:#eef3f1;border:1px solid var(--rule);border-radius:5px;padding:1px 6px;font-size:.85em}
/* inline diagram frame, light-paper variant */
figure.figic{margin:26px 0;background:var(--card);border:1px solid var(--rule);border-radius:14px;
  padding:20px 20px 13px}
figure.figic svg{display:block;width:100%;height:auto;max-width:760px;margin:0 auto}
figure.figic figcaption{font-family:var(--head);font-size:.79rem;color:var(--soft);
  text-align:center;margin-top:11px;font-weight:500}
.figic .d-box{fill:#fbfaf6;stroke:#bfe9e2;stroke-width:1.2}
.figic .d-head{font-family:'Sora',system-ui,sans-serif;font-size:11.5px;fill:#13201d;font-weight:600}
.figic .d-sub{font-family:'Inter',sans-serif;font-size:9.5px;fill:#5d6b66}
.figic .d-axis{font-family:'Sora',sans-serif;font-size:10px;fill:#5d6b66}
.figic .d-yes{fill:#0f9e6e;font-family:'Sora',sans-serif;font-size:13px;font-weight:700}
.figic .d-no{fill:#c2603f;font-family:'Sora',sans-serif;font-size:13px;font-weight:700}
/* Related block at the foot of a leaf or hub page */
.kin{margin:32px 0 0;border-top:1px solid var(--rule);padding-top:22px}
.kin .cap{font-family:var(--head);font-size:.73rem;letter-spacing:.15em;text-transform:uppercase;
  color:var(--teal-d);font-weight:600;margin-bottom:13px}
.kin .set{display:grid;gap:11px}
@media(min-width:620px){.kin .set{grid-template-columns:1fr 1fr}}
.kin a.k{display:block;border:1px solid var(--rule);border-radius:11px;padding:13px 15px;
  background:var(--card);color:var(--ink)}
.kin a.k:hover{border-color:#bfe9e2;text-decoration:none}
.kin a.k b{color:var(--teal-d);display:block;font-size:.95rem;font-family:var(--head);font-weight:600}
.kin a.k span{color:var(--soft);font-size:.84rem}
.gradebar{font-family:var(--head);color:var(--teal-d);font-weight:600}
@media(max-width:719px){.bsw-links{display:none}.bsw-burger{display:block}}

/* a11y + responsive polish */
:focus-visible{outline:2px solid currentColor;outline-offset:3px;border-radius:3px}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{animation-duration:.01ms !important;transition-duration:.01ms !important}}
@media(max-width:719px){th,td{padding:8px 10px}}
/* phone: data tables become one stacked card per row, each cell self-labelled */
@media(max-width:768px){.spread{overflow-x:visible;margin:18px 0}.spread table,.spread tbody,.spread tr,.spread td{display:block;width:100%}.spread thead{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0 0 0 0);white-space:nowrap;border:0}.spread table{min-width:0;border:0}.spread tr{border:1px solid var(--rule);border-radius:12px;background:var(--card2);padding:6px 14px;margin:0 0 14px}.spread tr.flagship{border-color:var(--teal);box-shadow:inset 3px 0 0 var(--teal)}.spread tr.flagship td{background:transparent}.spread td{border:0;border-bottom:1px solid var(--rule);padding:9px 0;display:flex;justify-content:space-between;gap:14px;align-items:baseline;text-align:right}.spread tr td:last-child{border-bottom:0}.spread td::before{content:attr(data-label);font-family:var(--head);font-size:.68rem;letter-spacing:.08em;text-transform:uppercase;color:var(--soft);font-weight:600;text-align:left;flex:0 0 auto;padding-right:8px}.spread td:first-child{font-size:1rem}.spread td:first-child::before{align-self:center}}