:root{
  --page:#F5F5F7; --card:#FFFFFF; --card-2:#F5F5F7; --card-3:#E8E8ED;
  --ink:#1D1D1F; --ink-2:#6E6E73; --ink-3:#6E6E73;
  --rule:#D2D2D7; --rule-soft:#E5E5EA;
  --accent:#0066CC; --accent-fill:#0066CC; --accent-tint:rgba(0,102,204,.08); --accent-line:rgba(0,102,204,.28);
  --c1:#0B7D63; --c2:#9C5F0C; --c3:#5A4FC4;
  --c1-t:rgba(11,125,99,.10); --c2-t:rgba(156,95,12,.10); --c3-t:rgba(90,79,196,.10);
  --wrong:#B3261E; --wrong-tint:rgba(179,38,30,.08);
  --gold:#7A5A00; --gold-tint:rgba(122,90,0,.09);
  --btn-ink:#FFFFFF; --on-fill:#FFFFFF; --label-ink:#5A5A5F; --c2-ink:#85520A; --c3-ink:#4E43B8;
  --shadow:0 2px 8px rgba(0,0,0,.04), 0 12px 32px rgba(0,0,0,.05);
  --r-lg:18px; --r-md:12px; --r-sm:8px;
  --f-body:"Helvetica Neue",-apple-system,BlinkMacSystemFont,Helvetica,Arial,"Segoe UI",Roboto,sans-serif;
  --f-display:var(--f-body);
  --f-mono:ui-monospace,"SF Mono",SFMono-Regular,Menlo,Monaco,Consolas,"Liberation Mono",monospace;
}
@media (prefers-color-scheme:dark){:root:not([data-theme="light"]){
  --page:#000000; --card:#1D1D1F; --card-2:#161617; --card-3:#2C2C2E;
  --ink:#F5F5F7; --ink-2:#A1A1A6; --ink-3:#A1A1A6;
  --rule:#38383C; --rule-soft:#2A2A2D;
  --accent:#2997FF; --accent-fill:#0071E3; --accent-tint:rgba(41,151,255,.12); --accent-line:rgba(41,151,255,.32);
  --c1:#22A385; --c2:#B5811F; --c3:#7F77D2;
  --c1-t:rgba(34,163,133,.14); --c2-t:rgba(181,129,31,.14); --c3-t:rgba(127,119,210,.14);
  --wrong:#FF6961; --wrong-tint:rgba(255,105,97,.12);
  --gold:#E0B54A; --gold-tint:rgba(224,181,74,.12);
  --btn-ink:#FFFFFF; --on-fill:#000000; --label-ink:#A1A1A6; --c2-ink:#D9A23F; --c3-ink:#9A93E4;
  --shadow:none;
}}
:root[data-theme="dark"]{
  --page:#000000; --card:#1D1D1F; --card-2:#161617; --card-3:#2C2C2E;
  --ink:#F5F5F7; --ink-2:#A1A1A6; --ink-3:#A1A1A6;
  --rule:#38383C; --rule-soft:#2A2A2D;
  --accent:#2997FF; --accent-fill:#0071E3; --accent-tint:rgba(41,151,255,.12); --accent-line:rgba(41,151,255,.32);
  --c1:#22A385; --c2:#B5811F; --c3:#7F77D2;
  --c1-t:rgba(34,163,133,.14); --c2-t:rgba(181,129,31,.14); --c3-t:rgba(127,119,210,.14);
  --wrong:#FF6961; --wrong-tint:rgba(255,105,97,.12);
  --gold:#E0B54A; --gold-tint:rgba(224,181,74,.12);
  --btn-ink:#FFFFFF; --on-fill:#000000; --label-ink:#A1A1A6; --c2-ink:#D9A23F; --c3-ink:#9A93E4;
  --shadow:none;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;-webkit-text-size-adjust:100%}
body{margin:0;background:var(--page);color:var(--ink);font-family:var(--f-body);
  font-size:17px;line-height:1.5;letter-spacing:-.011em;-webkit-font-smoothing:antialiased;
  -moz-osx-font-smoothing:grayscale;padding:0 22px 7rem}
button{font:inherit;color:inherit;letter-spacing:inherit}
a{color:var(--accent);text-decoration:none}
a:hover{text-decoration:underline}
:focus-visible{outline:3px solid var(--accent);outline-offset:3px;border-radius:6px}
@media (prefers-reduced-motion:reduce){*{transition:none!important;animation:none!important;scroll-behavior:auto!important}}

#prog{position:fixed;top:0;left:0;right:0;height:2px;z-index:90}
#prog i{display:block;height:100%;width:0;background:var(--accent);transition:width .12s linear}

header.top{position:sticky;top:0;z-index:80;background:color-mix(in srgb,var(--page) 82%,transparent);
  -webkit-backdrop-filter:saturate(180%) blur(20px);backdrop-filter:saturate(180%) blur(20px);
  border-bottom:1px solid var(--rule);margin:0 -22px;padding:0 22px}
.top .in{max-width:1024px;margin:0 auto;display:flex;align-items:center;gap:1rem;justify-content:space-between;min-height:48px}
.brand{display:flex;align-items:center;gap:.55rem;cursor:pointer;background:none;border:0;padding:0}
.brand .mark{font-family:var(--f-mono);font-size:11px;font-weight:600;letter-spacing:.04em;
  background:var(--accent-fill);color:#fff;padding:.2rem .42rem;border-radius:5px}
.brand .nm{font-size:15px;font-weight:600;letter-spacing:-.014em}
.crumb{font-size:13px;color:var(--ink-2);display:flex;gap:.4rem;align-items:center}
.crumb a{color:var(--accent)}
@media (max-width:36rem){.brand .nm{display:none}}

.wrap{max-width:1024px;margin:0 auto}
.read{max-width:700px;margin:0 auto}
.mid{max-width:860px;margin:0 auto}

h1{font-size:clamp(2.6rem,6.4vw,4rem);font-weight:600;line-height:1.05;letter-spacing:-.028em;margin:0;text-wrap:balance}
h2{font-size:clamp(1.9rem,4.2vw,2.75rem);font-weight:600;line-height:1.08;letter-spacing:-.024em;margin:0;text-wrap:balance}
h3{font-size:1.35rem;font-weight:600;line-height:1.22;letter-spacing:-.018em;margin:0}
h4{font-size:1.0625rem;font-weight:600;letter-spacing:-.014em;margin:0}
p{margin:0;max-width:36em}
.eyebrow{font-size:15px;font-weight:600;letter-spacing:-.01em;color:var(--accent);margin:0}
.dim{color:var(--ink-2)}
.tiny{font-size:14px;line-height:1.45}
.mono{font-family:var(--f-mono);font-size:.92em;letter-spacing:0}
.stack{display:flex;flex-direction:column}
.g03{gap:.35rem}.g05{gap:.6rem}.g075{gap:.85rem}.g1{gap:1.1rem}.g15{gap:1.6rem}.g2{gap:2.2rem}.g3{gap:3.2rem}.g45{gap:5rem}
.row{display:flex;flex-wrap:wrap;gap:.7rem;align-items:center}
hr.sep{border:0;border-top:1px solid var(--rule-soft);margin:0}

/* badges */
.badge{font-size:13px;font-weight:500;letter-spacing:-.006em;padding:.24rem .62rem;border-radius:980px;
  background:var(--card-3);color:var(--label-ink);white-space:nowrap;display:inline-block}
.badge.on{background:var(--accent-tint);color:var(--accent)}
.badge.soon{background:transparent;border:1px solid var(--rule);color:var(--label-ink)}
.badge.new{background:var(--c2-t);color:var(--c2-ink)}

/* buttons */
.btn{background:var(--accent-fill);color:var(--btn-ink);border:0;border-radius:980px;padding:.72rem 1.35rem;
  font-size:17px;font-weight:500;letter-spacing:-.014em;cursor:pointer;text-decoration:none;
  display:inline-flex;align-items:center;gap:.45rem;transition:opacity .15s ease}
.btn:hover{opacity:.86;text-decoration:none}
.btn.ghost{background:transparent;color:var(--accent);border:1px solid var(--rule)}
.btn.ghost:hover{background:var(--accent-tint);opacity:1}
.btn.sm{padding:.45rem .95rem;font-size:15px}
.btn[disabled]{opacity:.4;cursor:not-allowed}

/* hub hero */
.hero{padding:3.6rem 0 2.4rem;display:flex;flex-direction:column;gap:1.25rem;align-items:center;text-align:center}
.hero h1{max-width:16ch}
.hero .lede{font-size:clamp(1.2rem,2.4vw,1.55rem);line-height:1.35;letter-spacing:-.018em;color:var(--ink-2);max-width:34ch}
.hero .row{justify-content:center}
.metastrip{display:flex;flex-wrap:wrap;justify-content:center;gap:.4rem 1.4rem;font-size:14px;color:var(--ink-2);
  border-top:1px solid var(--rule);padding-top:1.3rem;margin-top:.8rem;width:100%}

.hubsec{align-items:center;text-align:center}
.hubsec h2{max-width:18ch}
.howgrid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem}
@media (max-width:38rem){.howgrid{grid-template-columns:1fr}}
.howgrid>div{background:var(--card);border-radius:var(--r-lg);padding:1.5rem 1.6rem;display:flex;flex-direction:column;gap:.5rem;box-shadow:var(--shadow)}
.howgrid b{font-size:1.15rem;font-weight:600;letter-spacing:-.018em}
.howgrid p{font-size:15px;line-height:1.5;color:var(--ink-2);max-width:none}

/* topic cards */
.tcard{background:var(--card);border-radius:var(--r-lg);overflow:hidden;box-shadow:var(--shadow)}
.tcard.dis{box-shadow:none;background:var(--card);opacity:.72}
.tcard .th{display:grid;grid-template-columns:auto 1fr auto;gap:.5rem 1.1rem;align-items:start;padding:1.7rem 1.8rem}
.tcard .num{font-size:1.9rem;font-weight:600;color:var(--accent);line-height:1;letter-spacing:-.03em;font-variant-numeric:tabular-nums}
.tcard.dis .num{color:var(--ink-2)}
.tcard h3{font-size:1.45rem}
.tcard.dis h3{color:var(--ink-2)}
.tcard .vp{grid-column:2;font-size:17px;color:var(--ink-2);margin-top:.25rem;line-height:1.45}
.tcard .sub{grid-column:2;font-size:14px;color:var(--ink-2);margin-top:.5rem;line-height:1.5}
.tcard .tb{border-top:1px solid var(--rule-soft);padding:1.5rem 1.8rem;display:flex;flex-direction:column;gap:1rem;background:var(--card-2)}
.tcard .grouplbl{font-size:14px;font-weight:600;color:var(--ink-2);letter-spacing:-.006em}
@media (max-width:32rem){
  .tcard .th{grid-template-columns:auto 1fr;padding:1.3rem 1.25rem}
  .tcard .th .badge{grid-column:2;justify-self:start}
  .tcard .tb{padding:1.2rem 1.25rem}
}

.linklist{display:flex;flex-direction:column;background:var(--card);border-radius:var(--r-md);overflow:hidden}
.linkrow{background:transparent;border:0;border-top:1px solid var(--rule-soft);text-align:left;width:100%;cursor:pointer;
  display:grid;grid-template-columns:1fr auto;gap:.25rem 1.1rem;align-items:center;padding:1rem 1.2rem;
  transition:background .12s ease}
.linkrow:first-child{border-top:0}
.linkrow:hover{background:var(--accent-tint)}
.linkrow .n{grid-column:1;grid-row:1;font-weight:600;font-size:17px;letter-spacing:-.016em}
.linkrow .d{grid-column:1;grid-row:2;font-size:15px;color:var(--ink-2);line-height:1.45}
.linkrow .go{grid-column:2;grid-row:1/3;font-size:15px;color:var(--accent);align-self:center;white-space:nowrap;font-weight:500}

/* tool + panel */
.toolhead{padding:3.5rem 0 1.6rem;display:flex;flex-direction:column;gap:1rem}
.panel{background:var(--card);border-radius:var(--r-lg);overflow:hidden;box-shadow:var(--shadow)}
.panel>.ph{padding:1.25rem 1.5rem;border-bottom:1px solid var(--rule-soft);display:flex;justify-content:space-between;
  align-items:baseline;gap:1rem;flex-wrap:wrap}
.panel>.ph b{font-size:1.2rem;font-weight:600;letter-spacing:-.018em}
.panel>.ph span{font-size:14px;color:var(--ink-2)}
.panel>.pb{padding:1.5rem;display:flex;flex-direction:column;gap:1.2rem}
@media (max-width:32rem){.panel>.ph{padding:1.1rem 1.15rem}.panel>.pb{padding:1.15rem}}

.item{border-radius:var(--r-md);padding:1.1rem 1.2rem;display:flex;flex-direction:column;gap:.85rem;background:var(--card-2)}
.opts{display:flex;flex-wrap:wrap;gap:.45rem}
.opt{border:1px solid var(--rule);background:var(--card);border-radius:980px;padding:.42rem 1rem;font-size:15px;
  cursor:pointer;font-weight:500;letter-spacing:-.01em;transition:border-color .12s ease}
.opt:hover:not([disabled]){border-color:var(--accent)}
.opt[data-s="right"]{background:var(--accent-tint);border-color:var(--accent);color:var(--accent)}
.opt[data-s="wrong"]{background:var(--wrong-tint);border-color:var(--wrong);color:var(--wrong)}
.opt[data-s="answer"]{border-color:var(--accent);border-style:dashed;color:var(--accent)}
.opt[disabled]{cursor:default}
.fb{font-size:15px;line-height:1.5;color:var(--ink-2);border-left:2px solid var(--accent-line);padding-left:.9rem}

.mcq{display:flex;flex-direction:column;gap:.6rem}
.mcq .qt{font-size:17px;font-weight:600;letter-spacing:-.016em;line-height:1.35}
.choice{text-align:left;background:var(--card-2);border:1px solid transparent;border-radius:var(--r-md);padding:.8rem 1rem;
  cursor:pointer;display:grid;grid-template-columns:1.4rem 1fr;gap:.6rem;font-size:16px;line-height:1.45;align-items:start;
  transition:border-color .12s ease}
.choice:hover:not([disabled]){border-color:var(--accent)}
.choice .k{font-size:14px;color:var(--ink-2);font-weight:600}
.choice[data-s="right"]{background:var(--accent-tint);border-color:var(--accent)}
.choice[data-s="wrong"]{background:var(--wrong-tint);border-color:var(--wrong)}
.choice[data-s="answer"]{border-color:var(--accent);border-style:dashed}
.choice .ex{grid-column:2;font-size:15px;color:var(--ink-2);margin-top:.4rem;line-height:1.45}
.choice[disabled]{cursor:default}

.scorebar{display:flex;align-items:baseline;gap:1.2rem;flex-wrap:wrap}
.scorebar .big{font-size:3.2rem;font-weight:600;line-height:1;letter-spacing:-.03em;font-variant-numeric:tabular-nums;color:var(--accent)}

.lvlpick{display:flex;gap:.4rem;flex-wrap:wrap;background:var(--card-3);padding:3px;border-radius:11px}
.lvlpick button{flex:1;min-width:7rem;border:0;background:transparent;border-radius:9px;padding:.55rem .5rem;
  cursor:pointer;font-size:15px;font-weight:500;letter-spacing:-.01em;color:var(--label-ink)}
.lvlpick button[aria-pressed="true"]{background:var(--card);color:var(--ink);font-weight:600;box-shadow:0 1px 3px rgba(0,0,0,.1)}
.bars{display:flex;flex-direction:column;gap:.9rem}
.bar1 .lb{display:flex;justify-content:space-between;font-size:15px;margin-bottom:.35rem;align-items:baseline}
.bar1 .lb i{font-style:normal;display:inline-block;width:.65rem;height:.65rem;border-radius:3px;margin-right:.5rem}
.bar1 .lb b{font-weight:500;font-variant-numeric:tabular-nums;color:var(--ink-2)}
.track{height:10px;background:var(--card-3);border-radius:5px;overflow:hidden}
.track i{display:block;height:100%;border-radius:5px;transition:width .3s ease}

.cal{display:flex;flex-direction:column;background:var(--card-2);border-radius:var(--r-md);overflow:hidden}
.cal button{background:transparent;border:0;border-top:1px solid var(--rule-soft);text-align:left;cursor:pointer;width:100%;
  display:grid;grid-template-columns:3.6rem 1fr auto;gap:.25rem 1rem;align-items:baseline;padding:.9rem 1.1rem;font-size:16px;line-height:1.45}
.cal button:first-child{border-top:0}
.cal button:hover{background:var(--accent-tint)}
.cal button.shown{box-shadow:inset 3px 0 0 var(--accent)}
.cal .t{font-family:var(--f-mono);font-size:14px;color:var(--ink-2);font-variant-numeric:tabular-nums}
.cal .r{font-size:14px;color:var(--accent);font-weight:600;white-space:nowrap}
.cal .why{grid-column:2/-1;font-size:15px;color:var(--ink-2);margin-top:.4rem;line-height:1.45}

.flash{background:var(--card-2);border-radius:var(--r-lg);padding:2.6rem 1.5rem;display:flex;flex-direction:column;gap:1rem;
  align-items:center;text-align:center;min-height:13rem;justify-content:center}
.flash .term{font-size:1.9rem;font-weight:600;letter-spacing:-.024em;line-height:1.15}
.flash .def{color:var(--ink-2);max-width:44ch;font-size:16px;line-height:1.5}
.flash .src2{font-size:14px;color:var(--ink-2);font-weight:500}

.myth{display:flex;flex-direction:column;gap:1.1rem}
.mythcard{border-radius:var(--r-lg);overflow:hidden;background:var(--card-2)}
.mythcard .mh{padding:1.3rem 1.4rem;display:flex;flex-direction:column;gap:.75rem;align-items:flex-start}
.mythcard .claim{font-size:1.3rem;line-height:1.3;letter-spacing:-.02em;font-weight:500}
.mythcard .mb{padding:0 1.4rem 1.4rem;display:flex;flex-direction:column;gap:.9rem}
.fact{display:grid;grid-template-columns:auto 1fr;gap:0 1.4rem;align-items:start;max-width:38em;
  background:var(--card);border-radius:var(--r-md);padding:1.25rem 1.4rem;box-shadow:var(--shadow)}
.fact .n{font-size:clamp(2rem,5.5vw,2.9rem);font-weight:700;letter-spacing:-.045em;color:var(--accent);
  line-height:1.05;font-variant-numeric:tabular-nums;white-space:nowrap}
.fact .b{display:flex;flex-direction:column;gap:.45rem;min-width:0}
.fact .h{font-size:17px;font-weight:600;line-height:1.35;letter-spacing:-.015em;color:var(--ink)}
.fact p{margin:0;font-size:15.5px;line-height:1.5;color:var(--ink-2);max-width:none}
.fact cite{font-style:normal;font-size:13.5px;color:var(--ink-2)}
.fact b{color:var(--ink);font-weight:600}
@media (max-width:600px){.fact{grid-template-columns:1fr;gap:.65rem}}
.factbox{background:var(--card);border-radius:var(--r-md);padding:1.1rem 1.25rem;display:flex;flex-direction:column;gap:.6rem}
.factbox b{font-size:14px;font-weight:600;color:var(--accent)}
.factbox>span{font-size:17px;line-height:1.45;letter-spacing:-.012em}
.evid{display:flex;flex-direction:column;gap:.45rem;font-size:15px;color:var(--ink-2);line-height:1.45}
.evid span{padding-left:1.1rem;position:relative}
.evid span::before{content:"";position:absolute;left:0;top:.62em;width:5px;height:5px;border-radius:50%;background:var(--accent)}
.evid b{font-family:var(--f-mono);color:var(--ink);font-size:.92em;font-weight:600}

.confgrid{display:flex;flex-direction:column;background:var(--card-2);border-radius:var(--r-md);overflow:hidden}
.confrow{background:transparent;border-top:1px solid var(--rule-soft);display:grid;grid-template-columns:1fr auto;
  gap:.6rem 1rem;align-items:center;padding:.9rem 1.1rem;font-size:16px}
.confrow:first-child{border-top:0}
.confrow .bs{display:flex;gap:.35rem}
.confrow .bs button{border:1px solid var(--rule);background:var(--card);border-radius:980px;padding:.32rem .8rem;
  font-size:14px;cursor:pointer;white-space:nowrap;font-weight:500}
.confrow .bs button[aria-pressed="true"]{background:var(--accent-fill);color:#fff;border-color:var(--accent-fill);font-weight:600}
@media (max-width:34rem){.confrow{grid-template-columns:1fr}.confrow .bs button{flex:1}}
.crow{display:grid;grid-template-columns:1fr auto;gap:.35rem 1rem;align-items:center;padding:.75rem 0;
  border-bottom:1px solid var(--rule-soft);font-size:16px;line-height:1.4}
.crow:last-child{border-bottom:0}
.tag{font-size:13px;font-weight:600;padding:.2rem .6rem;border-radius:980px;white-space:nowrap}
.tag.ok{background:var(--accent-tint);color:var(--accent)}
.tag.over{background:var(--wrong-tint);color:var(--wrong)}
.tag.under{background:var(--gold-tint);color:var(--gold)}

/* study guide */
section.part{padding-top:2.2rem;scroll-margin-top:5rem;display:flex;flex-direction:column;gap:1.7rem}
.pnum{font-size:15px;font-weight:600;color:var(--accent)}
.lede2{font-size:clamp(1.25rem,2.6vw,1.55rem);line-height:1.35;letter-spacing:-.018em;max-width:32ch;font-weight:400}
.defn{background:var(--card);border-radius:var(--r-md);padding:1.2rem 1.35rem;font-size:17px;line-height:1.5;max-width:36em;box-shadow:var(--shadow)}
.defn b{display:block;font-size:14px;font-weight:600;color:var(--accent);margin-bottom:.5rem}
.defn cite{display:block;font-style:normal;font-size:14px;color:var(--ink-2);margin-top:.6rem}
.defn em{font-style:italic}
blockquote{margin:0;padding-left:1.2rem;border-left:3px solid var(--accent-line);font-size:1.28rem;line-height:1.36;
  letter-spacing:-.019em;max-width:26em;font-weight:400}
blockquote cite{display:block;font-size:14px;font-style:normal;color:var(--ink-2);margin-top:.7rem;line-height:1.4;letter-spacing:-.01em}
.aside{background:var(--gold-tint);border-radius:var(--r-md);padding:1.2rem 1.35rem;display:flex;flex-direction:column;gap:.55rem;max-width:36em}
.aside b{font-size:14px;font-weight:600;color:var(--gold)}
.aside p{font-size:16px;line-height:1.5;max-width:none}
.clash{background:var(--c3-t);border-radius:var(--r-md);padding:1.2rem 1.35rem;display:flex;flex-direction:column;gap:.55rem;max-width:36em}
.clash b{font-size:14px;font-weight:600;color:var(--c3-ink)}
.clash p{font-size:16px;line-height:1.5;max-width:none}
ul.list{margin:0;padding:0;list-style:none;display:flex;flex-direction:column;gap:.8rem;max-width:36em}
ul.list li{padding-left:1.35rem;position:relative;color:var(--ink-2);line-height:1.5}
ul.list li::before{content:"";position:absolute;left:.15rem;top:.6em;width:6px;height:6px;border-radius:50%;background:var(--accent)}
ul.list b{color:var(--ink);font-weight:600}
ol.num{margin:0;padding-left:1.5rem;display:flex;flex-direction:column;gap:.6rem;max-width:36em;color:var(--ink-2);line-height:1.5}
ol.num b{color:var(--ink);font-weight:600}
.src{font-size:14px;color:var(--ink-2);line-height:1.6;border-top:1px solid var(--rule-soft);padding-top:.9rem;max-width:36em}
.scroller{overflow-x:auto;border-radius:var(--r-md);background:var(--card);box-shadow:var(--shadow)}
table{border-collapse:collapse;width:100%;min-width:34rem;font-size:16px}
th{text-align:left;font-size:14px;color:var(--ink-2);font-weight:600;padding:.9rem 1.1rem;border-bottom:1px solid var(--rule);background:var(--card-2)}
td{padding:.9rem 1.1rem;border-bottom:1px solid var(--rule-soft);vertical-align:top;color:var(--ink-2);line-height:1.45}
td:first-child{color:var(--ink);font-weight:600;width:9.5rem}
tr:last-child td{border-bottom:0}
.ref{display:grid;grid-template-columns:1.9rem 1fr;gap:.5rem .8rem;font-size:16px;padding:.85rem 0;border-bottom:1px solid var(--rule-soft);line-height:1.45}
.ref:last-child{border-bottom:0}
.ref .n{font-size:14px;color:var(--ink-2);font-variant-numeric:tabular-nums}
.ref .d{color:var(--ink-2)}
.ref .d b{color:var(--ink);font-weight:600}
.note2{background:var(--card);border-radius:var(--r-md);border-left:3px solid var(--c3);padding:1.25rem 1.4rem;
  display:flex;flex-direction:column;gap:.6rem;box-shadow:var(--shadow)}
.note2 b{font-size:14px;font-weight:600;color:var(--c3-ink)}
.note2 p{font-size:16px;line-height:1.5;max-width:none}

/* figures */
figure.fig{margin:0;background:var(--card);border-radius:var(--r-lg);padding:1.7rem 1.5rem 1.4rem;
  display:flex;flex-direction:column;gap:1.1rem;box-shadow:var(--shadow)}
figure.fig svg{width:100%;height:auto;display:block;max-width:100%}
figcaption{font-size:15px;line-height:1.5;color:var(--ink-2);max-width:56ch}
figcaption b{color:var(--ink);font-weight:600}
.figtag{font-size:14px;color:var(--ink-2);font-weight:500}
.fig .s{opacity:0;transition:opacity .55s ease,transform .55s ease}
.fig .s.on{opacity:1;transform:none}
.fig .up{transform:translateY(14px)}
.fig .dr{stroke-dashoffset:1;transition:stroke-dashoffset .8s ease,opacity .4s ease}
.fig .dr.on{stroke-dashoffset:0}
@media (prefers-reduced-motion:reduce){.fig .s{opacity:1;transform:none}.fig .dr{stroke-dashoffset:0}}
svg text{font-family:var(--f-body);fill:currentColor;letter-spacing:-.01em}
.t-lab{font-size:13px;font-weight:600}
.t-sm{font-size:11.5px;fill:var(--ink-2)}
.t-mono{font-family:var(--f-mono);font-size:11px;fill:var(--ink-2);font-weight:500}
.t-inv{font-size:11.5px;fill:var(--on-fill);font-weight:600}
.q-box{fill:var(--card-2)} .q-good{fill:var(--c1-t)} .q-bad{fill:var(--wrong-tint)}
.axis{stroke:var(--ink-2);fill:none;stroke-width:1.5}
.c1{color:var(--c1)} .c2{color:var(--c2-ink)} .c3{color:var(--c3-ink)}
.f1{fill:var(--c1)} .f2{fill:var(--c2)} .f3{fill:var(--c3)}


/* ---------- tiles ---------- */
.tiles{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:1rem}
.tile{background:var(--card);border:0;border-radius:var(--r-lg);box-shadow:var(--shadow);cursor:pointer;
  text-align:left;padding:1.35rem 1.4rem;display:flex;flex-direction:column;gap:.55rem;min-height:170px;
  transition:transform .16s ease, box-shadow .16s ease;position:relative;color:inherit}
.tile:hover{transform:translateY(-3px);box-shadow:0 4px 12px rgba(0,0,0,.07),0 18px 40px rgba(0,0,0,.08)}
:root[data-theme="dark"] .tile:hover, :root:not([data-theme="light"]) .tile:hover{box-shadow:0 0 0 1px var(--rule)}
.tile .tnum{font-size:1.55rem;font-weight:600;color:var(--accent);line-height:1;letter-spacing:-.03em;font-variant-numeric:tabular-nums}
.tile .ttl{font-size:1.08rem;font-weight:600;letter-spacing:-.018em;line-height:1.25}
.tile .tsub{font-size:14px;color:var(--ink-2);line-height:1.45;flex:1}
.tile .tfoot{display:flex;align-items:center;gap:.5rem;flex-wrap:wrap;font-size:13px;color:var(--ink-2);margin-top:.2rem}
.tile.locked{cursor:default;box-shadow:none;background:var(--card);opacity:.6}
.tile.locked:hover{transform:none;box-shadow:none}
.tile.locked .tnum{color:var(--ink-2)}
.tile.wide{grid-column:1/-1;min-height:0;flex-direction:row;align-items:center;gap:1.1rem;flex-wrap:wrap}
.tile.wide .tsub{flex:1 1 260px}
.tick{display:inline-flex;align-items:center;justify-content:center;width:19px;height:19px;border-radius:50%;
  background:var(--accent-fill);color:#fff;font-size:12px;font-weight:700;line-height:1;flex:none}
.tile .cornertick{position:absolute;top:1rem;right:1rem}

/* ---------- stepper ---------- */
.stepwrap{position:sticky;top:48px;z-index:60;background:color-mix(in srgb,var(--page) 88%,transparent);
  -webkit-backdrop-filter:saturate(180%) blur(20px);backdrop-filter:saturate(180%) blur(20px);
  margin:0 -22px;padding:.55rem 22px;border-bottom:1px solid var(--rule)}
.stepper{max-width:860px;margin:0 auto;display:flex;gap:.4rem;overflow-x:auto;scrollbar-width:none;padding-bottom:2px}
.stepper::-webkit-scrollbar{display:none}
.stepper button{flex:none;border:1px solid var(--rule);background:var(--card);border-radius:980px;
  padding:.34rem .8rem;font-size:14px;cursor:pointer;white-space:nowrap;color:var(--ink-2);
  display:inline-flex;align-items:center;gap:.35rem;font-weight:500}
.stepper button:hover{border-color:var(--accent)}
.stepper button[aria-current="true"]{background:var(--accent-fill);border-color:var(--accent-fill);color:#fff;font-weight:600}
.stepper button .dot{width:6px;height:6px;border-radius:50%;background:var(--accent);flex:none}
.stepper button[aria-current="true"] .dot{background:#fff}

/* ---------- pager ---------- */
.pager{display:grid;grid-template-columns:1fr 1fr;gap:.9rem;margin-top:3rem}
.pager button{background:var(--card);border:0;box-shadow:var(--shadow);border-radius:var(--r-lg);
  padding:1.1rem 1.3rem;cursor:pointer;text-align:left;display:flex;flex-direction:column;gap:.25rem;
  transition:transform .16s ease}
.pager button:hover{transform:translateY(-2px)}
.pager button[disabled]{opacity:.35;cursor:not-allowed;box-shadow:none;background:transparent;border:1px solid var(--rule)}
.pager button[disabled]:hover{transform:none}
.pager .lbl{font-size:13px;color:var(--ink-2)}
.pager .who{font-size:16px;font-weight:600;letter-spacing:-.014em;line-height:1.25}
.pager .next{text-align:right;align-items:flex-end}
@media (max-width:32rem){.pager{grid-template-columns:1fr}}

.readbar{display:flex;align-items:center;gap:.75rem;font-size:14px;color:var(--ink-2);flex-wrap:wrap}
.readbar .meter{flex:1;min-width:120px;height:6px;background:var(--card-3);border-radius:3px;overflow:hidden}
.readbar .meter i{display:block;height:100%;background:var(--accent);border-radius:3px;transition:width .3s ease}

@media (max-width:34rem){
  .tiles{grid-template-columns:1fr 1fr;gap:.7rem}
  .tile{min-height:0;padding:1rem .95rem;gap:.4rem}
  .tile .ttl{font-size:1rem}
  .tile .tsub{font-size:13px;display:-webkit-box;-webkit-line-clamp:4;-webkit-box-orient:vertical;overflow:hidden}
  .tile.wide{grid-column:1/-1;flex-direction:column;align-items:flex-start;padding:1.15rem}
  .tile.wide .tsub{-webkit-line-clamp:none;overflow:visible}
  .tile .tnum{font-size:1.3rem}
}
.sectionhead{display:flex;align-items:baseline;justify-content:space-between;gap:1rem;flex-wrap:wrap}

footer{border-top:1px solid var(--rule);padding-top:1.6rem;margin-top:6rem;font-size:14px;color:var(--ink-2);
  display:flex;flex-wrap:wrap;gap:.5rem 1.6rem}


/* ---------- links used as tiles / brand (multi-page site) ---------- */
a.tile, a.tile:hover{text-decoration:none;color:inherit}
a.brand, a.brand:hover{text-decoration:none;color:inherit}
.tile .ttl, .tile .tsub, .tile .tfoot{text-decoration:none}