:root{--paper:#fffef9;--ink:#1c1c1c;--muted:#52504b;--faint:#8a877f;--rule:#dcd9d0;--rule-strong:#1c1c1c;--accent:#a52a1a;--ok:#2c6e3f;--code-bg:#f6f4ee;--serif:"Charter", "Bitstream Charter", "Sitka Text", Cambria, Georgia, serif;--mono:"SF Mono", "Menlo", "Consolas", ui-monospace, monospace;--maxw:780px}*{box-sizing:border-box;margin:0;padding:0}html{scroll-behavior:smooth}body{background:var(--paper);color:var(--ink);font-family:var(--serif);font-size:18px;line-height:1.6}::selection{background:#f3e0dc}a{color:var(--accent);text-underline-offset:2px;text-decoration:underline;text-decoration-thickness:1px}a:hover{text-decoration-thickness:2px}code{font-family:var(--mono);background:var(--code-bg);border-radius:3px;padding:.1em .35em;font-size:.82em}pre{background:var(--code-bg);border:1px solid var(--rule);margin:1.2rem 0;padding:1rem 1.2rem;font-size:.8rem;line-height:1.65;overflow-x:auto}pre code{background:0 0;padding:0}.wrap{max-width:var(--maxw);margin:0 auto;padding:0 1.5rem}header.site{border-bottom:2px solid var(--rule-strong);background:var(--paper);padding:1rem 0}header.site .wrap{justify-content:space-between;align-items:baseline;display:flex}.brand{font-family:var(--serif);letter-spacing:.01em;color:var(--ink);font-size:1.05rem;font-weight:700;text-decoration:none}.brand b{color:var(--ink);font-weight:700}nav.top{gap:1.5rem;font-size:.9rem;display:flex}nav.top a{color:var(--muted);text-decoration:none}nav.top a:hover{color:var(--accent);text-decoration:underline}nav.top a.active{color:var(--ink)}footer.site{border-top:1px solid var(--rule);color:var(--faint);margin-top:5rem;padding:1.6rem 0 3rem;font-size:.85rem}.hero{padding:4rem 0 2.5rem}.kicker{color:var(--muted);margin-bottom:1rem;font-size:.85rem;font-style:italic;display:block}h1{letter-spacing:-.01em;max-width:22ch;font-size:clamp(2rem,5vw,3rem);font-weight:700;line-height:1.12}h1 em{color:var(--ink);font-style:italic}.hero p.lead{max-width:58ch;color:var(--muted);margin-top:1.3rem;font-size:1.05rem}.hero .meta{border-top:1px solid var(--rule);color:var(--muted);flex-wrap:wrap;gap:.4rem 2.5rem;margin-top:2rem;padding-top:1.2rem;font-size:.9rem;display:flex}.hero .meta div span{color:var(--ink);text-transform:none;letter-spacing:0;margin-right:.4rem;font-size:.9rem;font-weight:700;display:inline}.hero .meta div span:after{content:" —";color:var(--faint);font-weight:400}.modules{border-top:2px solid var(--rule-strong);margin-top:1.5rem;display:block}.module-card{border-bottom:1px solid var(--rule);color:var(--ink);grid-template-columns:3.2rem 1fr;gap:0 1.2rem;padding:1.3rem .2rem;text-decoration:none;display:grid}.module-card:hover{background:#faf8f1}.module-card:hover h3{text-decoration:underline;-webkit-text-decoration-color:var(--accent);text-decoration-color:var(--accent);text-underline-offset:3px}.module-card .num{color:var(--accent);grid-row:1/span 3;font-size:1rem;font-weight:700;line-height:1.5}.module-card h3{margin:0 0 .25rem;font-size:1.15rem;font-weight:700}.module-card p{color:var(--muted);max-width:60ch;font-size:.95rem}.module-card .tags{flex-wrap:wrap;gap:0 .3rem;margin-top:.45rem;display:flex}.tag{color:var(--faint);border:none;padding:0;font-size:.82rem;font-style:italic}.tag:not(:last-child):after{content:" ·"}.module-hero{border-bottom:1px solid var(--rule);padding:3.2rem 0 2rem}.module-hero h1{max-width:24ch;font-size:clamp(1.8rem,4vw,2.5rem)}.module-hero .num-big{color:var(--accent);margin-bottom:.6rem;font-size:.9rem;font-style:italic;display:block}section.block{padding:2.4rem 0 .2rem}h2{margin-bottom:1rem;font-size:1.4rem;font-weight:700;display:block}h2 .idx{color:var(--accent);margin-right:.6rem;font-size:.95rem;font-weight:700}h3{margin:1.5rem 0 .4rem;font-size:1.02rem;font-weight:700}section.block p{max-width:66ch;color:var(--ink);margin-bottom:.9rem}section.block ul,section.block ol{max-width:62ch;margin:.5rem 0 1.2rem 1.5rem}section.block li{margin-bottom:.4rem}.callout{border-left:3px solid var(--ink);color:var(--muted);max-width:64ch;margin:1.4rem 0;padding:.2rem 0 .2rem 1.1rem;font-size:.95rem}.callout.warn{border-left-color:var(--accent)}.callout.danger{border-left-color:var(--accent);border-left-width:5px}.callout b:first-child{color:var(--ink);margin-bottom:.15rem;display:block}.checklist{max-width:64ch;list-style:none;margin:.8rem 0 1.4rem!important}.checklist li{border-bottom:1px dotted var(--rule);margin:0}.checklist li:last-child{border-bottom:none}.checklist label{cursor:pointer;align-items:flex-start;gap:.7rem;padding:.5rem .2rem;display:flex}.checklist input{accent-color:var(--ink);flex-shrink:0;margin-top:.35rem}.checklist input:checked+span{color:var(--faint)}.quiz{border:1px solid var(--rule);border-top:2px solid var(--rule-strong);background:#fdfbf5;margin:1.4rem 0;padding:1.5rem 1.6rem}.quiz .q{margin-bottom:1.5rem}.quiz .q:last-of-type{margin-bottom:.4rem}.quiz .q p.question{margin-bottom:.6rem;font-weight:700}.quiz .q p.question .qnum{color:var(--accent);margin-right:.4rem}.quiz .opts{gap:.35rem;display:grid}.quiz .opts button{text-align:left;border:1px solid var(--rule);color:var(--ink);font-family:var(--serif);cursor:pointer;background:0 0;padding:.5rem .8rem;font-size:.95rem}.quiz .opts button:hover{border-color:var(--ink)}.quiz .opts button.correct{border-color:var(--ok);color:var(--ok);font-weight:700}.quiz .opts button.correct:before{content:"✓ "}.quiz .opts button.wrong{border-color:var(--accent);color:var(--accent);text-decoration:line-through}.quiz .q.answered .opts button{cursor:default}.quiz .explain{color:var(--muted);border-left:2px solid var(--rule);margin-top:.5rem;padding-left:.8rem;font-size:.88rem;font-style:italic;display:none}.quiz .q.answered .explain{display:block}.quiz-score{color:var(--ink);margin-top:.8rem;font-size:.95rem;font-weight:700}.pager{border-top:1px solid var(--rule);justify-content:space-between;gap:1rem;margin-top:3.5rem;padding-top:1.4rem;font-size:.92rem;display:flex}.res-grid{margin:1rem 0;display:block}.res{border-bottom:1px dotted var(--rule);padding:.7rem 0;font-size:.95rem}.res b{margin-right:.5rem;display:inline}.res span{color:var(--faint);font-size:.88rem}table.plan{border-collapse:collapse;width:100%;margin:1.2rem 0;font-size:.92rem}table.plan th{font-family:var(--serif);color:var(--ink);text-align:left;border-bottom:2px solid var(--rule-strong);padding:.45rem .8rem .45rem 0;font-size:.82rem;font-weight:700}table.plan td{border-bottom:1px solid var(--rule);color:var(--muted);vertical-align:top;padding:.55rem .8rem .55rem 0}table.plan td:first-child{font-family:var(--serif);color:var(--ink);white-space:nowrap;font-size:.92rem;font-style:italic}table.plan td strong{color:var(--ink)}.footer-row{flex-wrap:wrap;justify-content:space-between;gap:1rem;display:flex}.module-lead{color:var(--muted);max-width:56ch;margin-top:1rem;font-size:1.05rem}.deck{background:var(--paper);position:fixed;inset:0;overflow:hidden}.deck .slide{flex-direction:column;justify-content:safe center;padding:6vh 10vw calc(6vh + 2.5rem);display:none;position:absolute;inset:0;overflow-y:auto}.deck .slide.active{display:flex}.deck .kicker{color:var(--accent);margin-bottom:2.5vh;font-size:clamp(.8rem,1.2vw,1rem);font-style:italic;display:block}.deck h1{letter-spacing:-.01em;max-width:20ch;font-size:clamp(2.4rem,6vw,4.6rem);font-weight:700;line-height:1.08}.deck h1 em,.deck h2 em{color:var(--ink);font-style:italic}.deck h2{max-width:26ch;margin-bottom:3.5vh;font-size:clamp(1.9rem,4vw,3rem);font-weight:700;line-height:1.12}.deck .lead{color:var(--muted);max-width:54ch;margin-top:2.5vh;font-size:clamp(1.05rem,1.7vw,1.45rem);line-height:1.6}.deck ul.big{max-width:60ch;margin:0;font-size:clamp(1.05rem,1.8vw,1.5rem);line-height:1.5;list-style:none}.deck ul.big li{color:var(--muted);padding:1.2vh 0 1.2vh 1.8rem;position:relative}.deck ul.big li:before{content:"—";color:var(--accent);position:absolute;left:0}.deck ul.big li strong{color:var(--ink);font-weight:700}.deck .cols{grid-template-columns:1fr 1fr;align-items:start;gap:3vw;display:grid}.deck .cols-3{grid-template-columns:repeat(3,1fr);gap:2vw;display:grid}.deck .cols-2{grid-template-columns:repeat(2,1fr);gap:1.6vw;display:grid}.deck .card{border-top:2px solid var(--ink);background:0 0;padding:1.8vh 0 0}.deck .card h3{margin:0 0 1vh;font-size:clamp(1.05rem,1.7vw,1.4rem);font-weight:700}.deck .card h3 .n{color:var(--accent);margin-right:.5rem;font-style:italic;font-weight:400}.deck .card p{color:var(--muted);margin:0;font-size:clamp(.85rem,1.25vw,1.05rem);line-height:1.55}.deck pre{background:var(--code-bg);border:1px solid var(--rule);font-family:var(--mono);color:var(--ink);margin:0;padding:2.4vh 1.8vw;font-size:clamp(.78rem,1.25vw,1.05rem);line-height:1.7}.deck pre .c{color:#6e7781}.deck pre .g{color:var(--ok)}.deck pre .r{color:#cf222e}.deck pre .y{color:#9a6700}.deck pre .b{color:#0550ae}.deck .tag{color:var(--muted);font-size:clamp(.8rem,1.2vw,1rem);font-style:italic}.deck .tags-row{flex-wrap:wrap;gap:.8rem;margin-top:3.5vh;display:flex}.deck table{border-collapse:collapse;width:100%;margin:0;font-size:clamp(.85rem,1.35vw,1.15rem)}.deck th{color:var(--ink);text-align:left;border-bottom:2px solid var(--ink);padding:1vh 1vw 1vh 0;font-size:clamp(.75rem,1.1vw,.95rem);font-weight:700}.deck td{border-bottom:1px solid var(--rule);color:var(--muted);vertical-align:top;padding:1.4vh 1vw 1.4vh 0}.deck td:first-child{color:var(--ink);white-space:nowrap;font-style:italic}.deck td strong{color:var(--ink)}.deck .callout{border-left:3px solid var(--ink);max-width:64ch;color:var(--muted);margin:3vh 0 0;padding:.5vh 0 .5vh 1.4vw;font-size:clamp(.95rem,1.5vw,1.25rem)}.deck .callout.warn{border-left-color:var(--accent)}.deck .callout b{color:var(--ink)}.deck .callout b:first-child{margin-bottom:0;display:inline}.deck .progress{background:var(--accent);z-index:60;height:3px;transition:width .25s;position:fixed;top:0;left:0}.deck .hud{z-index:60;color:var(--faint);justify-content:space-between;padding:0 10vw;font-size:.8rem;font-style:italic;display:flex;position:fixed;bottom:2.4vh;left:0;right:0}.deck .hud .keys span{border:1px solid var(--rule);font-style:normal;font-family:var(--mono);margin-left:.35rem;padding:.05rem .4rem;font-size:.7rem}.deck .center{text-align:center;align-items:center}.deck .center h1,.deck .center h2{max-width:none}.deck .center .lead,.deck .center .kicker{margin-left:auto;margin-right:auto}.visually-hidden{clip-path:inset(50%);white-space:nowrap;border:0;width:1px;height:1px;margin:-1px;padding:0;position:absolute;overflow:hidden}@media (max-width:640px){.deck .cols,.deck .cols-2,.deck .cols-3{grid-template-columns:1fr}.deck .slide{padding:4vh 6vw calc(6vh + 2.5rem)}.deck .hud .keys{display:none}table.plan td:first-child,.deck td:first-child{white-space:normal}.hero .meta{flex-direction:column;gap:.4rem}}