:root{
  --paper:#F6F4EF; --white:#FFFFFF; --ink:#16211C; --ink-soft:#4B534E;
  --green:#2F7A52; --green-lt:#5FBF8C; --green-dk:#23603F; --red:#C0392B;
  --hair:rgba(22,33,28,0.08);
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{margin:0;background:var(--paper);color:var(--ink);
  font-family:'Inter',-apple-system,BlinkMacSystemFont,"Segoe UI",Helvetica,Arial,sans-serif;
  -webkit-font-smoothing:antialiased;}
a{color:var(--green);text-decoration:none;}
a:hover{color:var(--green-dk);}
::selection{background:var(--green);color:#fff;}
h1,h2,h3,h4,.archivo{font-family:'Archivo',sans-serif;}
.container{max-width:1320px;margin:0 auto;padding:0 32px;}

/* ---------- candlestick mark ---------- */
.mark{display:flex;align-items:center;gap:4px;height:28px;}
.candle{position:relative;border-radius:1px;}
.candle::before,.candle::after{content:"";position:absolute;left:50%;width:1.5px;
  transform:translateX(-50%);background:inherit;}
.c1{width:6px;height:16px;background:var(--green);}
.c1::before{top:-5px;height:5px;} .c1::after{bottom:-5px;height:5px;}
.c2{width:6px;height:24px;background:var(--red);}
.c2::before{top:-7px;height:7px;} .c2::after{bottom:-7px;height:7px;}
.c3{width:6px;height:14px;background:var(--green);}
.c3::before{top:-4px;height:4px;} .c3::after{bottom:-4px;height:4px;}

/* ---------- nav ---------- */
header.nav{position:sticky;top:0;z-index:50;background:rgba(246,244,239,0.92);
  backdrop-filter:blur(8px);border-bottom:1px solid var(--hair);}
.nav-inner{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:16px 0;}
.brand{display:flex;align-items:center;gap:10px;}
.brand-text{font-family:'Archivo',sans-serif;font-weight:900;font-size:16px;
  letter-spacing:.02em;line-height:1;color:var(--ink);}
.brand-text span{font-weight:700;color:var(--green);font-size:11px;letter-spacing:.18em;}
nav.links{display:flex;align-items:center;gap:28px;}
nav.links a{color:var(--ink);font-size:14px;font-weight:600;}
nav.links a:hover{color:var(--green);}
.btn-dark{background:var(--ink);color:var(--paper);padding:10px 20px;border-radius:4px;
  font-size:14px;font-weight:600;display:inline-block;}
.btn-dark:hover{background:var(--green);color:var(--paper);}
@media(max-width:860px){nav.links{display:none;}}

/* ---------- article ---------- */
.art{max-width:720px;margin:0 auto;padding:56px 32px 24px;}
.crumb{font-size:13px;font-weight:600;color:var(--ink-soft);margin-bottom:26px;}
.crumb a{color:var(--ink-soft);} .crumb a:hover{color:var(--green);}
.eyebrow{font-size:11px;font-weight:800;letter-spacing:.14em;text-transform:uppercase;
  color:var(--green);margin-bottom:14px;}
.art h1{font-weight:900;font-size:40px;line-height:1.1;letter-spacing:-.015em;margin:0 0 18px;}
.dek{font-size:19px;line-height:1.6;color:var(--ink-soft);margin:0 0 12px;}
.art hr{border:0;border-top:1px solid var(--hair);margin:34px 0;}
.art h2{font-weight:900;font-size:24px;line-height:1.25;margin:42px 0 14px;}
.art h3{font-weight:700;font-size:18px;margin:30px 0 10px;}
.art p{font-size:17px;line-height:1.72;margin:0 0 18px;}
.art ul,.art ol{font-size:17px;line-height:1.72;padding-left:22px;margin:0 0 20px;}
.art li{margin-bottom:9px;}
.art strong{font-weight:700;}
.art code{font-family:ui-monospace,SFMono-Regular,Menlo,monospace;font-size:15px;
  background:rgba(22,33,28,.06);padding:2px 6px;border-radius:3px;}
.callout{background:var(--white);border:1px solid var(--hair);border-left:3px solid var(--green);
  border-radius:6px;padding:20px 22px;margin:26px 0;}
.callout p{font-size:15.5px;line-height:1.65;margin:0;}
.callout p+p{margin-top:12px;}
.formula{background:var(--white);border:1px solid var(--hair);border-radius:6px;
  padding:16px 20px;margin:22px 0;font-family:ui-monospace,SFMono-Regular,Menlo,monospace;
  font-size:15px;line-height:1.7;color:var(--ink);overflow-x:auto;}
table{width:100%;border-collapse:collapse;margin:22px 0;font-size:15.5px;}
th,td{text-align:left;padding:10px 12px;border-bottom:1px solid var(--hair);vertical-align:top;}
th{font-weight:800;font-size:12px;letter-spacing:.08em;text-transform:uppercase;color:var(--ink-soft);}

/* ---------- next / prev ---------- */
.more{max-width:720px;margin:0 auto;padding:10px 32px 64px;}
.more h4{font-size:12px;font-weight:800;letter-spacing:.12em;text-transform:uppercase;
  color:var(--ink-soft);margin:0 0 14px;}
.more ul{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:10px;}
.more li{font-size:16px;}
.more li.soon{color:rgba(75,83,78,.55);}
.more li.soon::after{content:" \2014 in progress";font-size:13px;color:rgba(75,83,78,.45);}

/* ---------- footer ---------- */
footer.site{background:var(--ink);color:rgba(246,244,239,.72);padding:52px 0 34px;}
footer.site a{color:rgba(246,244,239,.9);}
footer.site a:hover{color:var(--green-lt);}
.foot-top{display:flex;flex-wrap:wrap;gap:20px;align-items:center;justify-content:space-between;
  padding-bottom:26px;border-bottom:1px solid rgba(246,244,239,.14);}
.foot-brand{font-family:'Archivo',sans-serif;font-weight:900;font-size:15px;letter-spacing:.02em;
  color:var(--paper);}
.foot-top nav{display:flex;flex-wrap:wrap;gap:20px;}
.foot-top nav a{font-size:14px;font-weight:600;}
.disclosures{padding-top:26px;}
.disclosures h4{font-size:11px;font-weight:800;letter-spacing:.14em;text-transform:uppercase;
  color:rgba(246,244,239,.5);margin:0 0 16px;}
.disclosures p{font-size:13px;line-height:1.7;margin:0 0 13px;max-width:80ch;}
.disclosures strong{color:var(--paper);}
.copyright{margin-top:22px;font-size:12.5px;color:rgba(246,244,239,.5);}
@media(max-width:640px){
  .art{padding:38px 22px 20px;} .more{padding:10px 22px 52px;}
  .art h1{font-size:31px;} .dek{font-size:17px;} .art p,.art ul,.art ol{font-size:16px;}
}

/* ---------- group / library index listings ---------- */
.art h2 em{font-style:normal;font-size:12px;font-weight:700;letter-spacing:.06em;
  text-transform:uppercase;color:var(--ink-soft);margin-left:10px;vertical-align:middle;}
.art h2 a{color:var(--ink);} .art h2 a:hover{color:var(--green);}
ol.toc{list-style:none;padding:0;margin:0 0 8px;}
ol.toc li{display:flex;gap:14px;align-items:baseline;padding:13px 0;
  border-bottom:1px solid var(--hair);margin:0;}
ol.toc li:last-child{border-bottom:0;}
ol.toc .idx{flex:0 0 auto;font-size:12px;font-weight:800;color:var(--green);
  font-variant-numeric:tabular-nums;}
ol.toc a{font-size:16.5px;line-height:1.45;color:var(--ink);font-weight:600;}
ol.toc a:hover{color:var(--green);}
ol.toc .sum{display:block;font-size:14.5px;line-height:1.55;color:var(--ink-soft);
  font-weight:400;margin-top:4px;}
.grouplinks{display:flex;flex-wrap:wrap;gap:10px;margin:26px 0 0;}
.grouplinks a{font-size:13px;font-weight:700;padding:8px 14px;border:1px solid var(--hair);
  border-radius:100px;background:var(--white);color:var(--ink);}
.grouplinks a:hover{border-color:var(--green);color:var(--green);}

/* ---------- figures ---------- */
.fig{margin:32px 0;background:var(--white);border:1px solid var(--hair);border-radius:10px;
  padding:24px 22px 20px;}
.fig svg{width:100%;height:auto;display:block;}
.fig figcaption{margin-top:16px;padding-top:14px;border-top:1px solid var(--hair);
  font-size:12.5px;line-height:1.6;color:var(--ink-soft);}