:root{--ink: #1c2230;--ink-soft: #4a5266;--bg: #f7f8fb;--surface: #ffffff;--line: #e2e6ef;--method-accent: #2f6fed;--method-bg: #f0f5ff;--method-line: #c5d8ff;--verify-accent: #1f9e6a;--verify-bg: #eefaf3;--verify-line: #b9e9d1;--example-accent: #7a4ddb;--example-bg: #f6f2ff;--example-line: #ddd0f7;--warn-accent: #b8730b;--warn-bg: #fff7e8;--warn-line: #f4d79b;--radius: 10px;--maxread: 70ch;--nav-w: 290px;--font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;--font-mono: "SFMono-Regular", ui-monospace, "Cascadia Code", Consolas, "Liberation Mono", Menlo, monospace}*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:1.5rem}body{margin:0;font-family:var(--font-body);color:var(--ink);background:var(--bg);font-size:18px;line-height:1.6;-webkit-font-smoothing:antialiased}a{color:var(--method-accent)}code,.path{font-family:var(--font-mono);font-size:.92em}.shell{display:grid;grid-template-columns:var(--nav-w) minmax(0,1fr);gap:2.5rem;max-width:1180px;margin:0 auto;padding:1.5rem clamp(1rem,3vw,2.5rem) 4rem}.sidebar{position:sticky;top:1.5rem;align-self:start;max-height:calc(100vh - 3rem);overflow-y:auto;padding-right:.5rem}.sidebar__brand{font-size:1rem;font-weight:700;line-height:1.3;margin:0 0 .25rem}.sidebar__sub{margin:0 0 1rem;color:var(--ink-soft);font-size:.85rem}.search{width:100%;font:inherit;font-size:.95rem;padding:.55rem .7rem;border:1px solid var(--line);border-radius:8px;background:var(--surface);margin-bottom:.5rem}.search:focus{outline:2px solid var(--method-accent);border-color:transparent}.search__hint{font-size:.75rem;color:var(--ink-soft);margin:0 0 1rem}.nav__chapter{margin-bottom:1rem}.nav__chapter-title{font-size:.78rem;text-transform:uppercase;letter-spacing:.04em;color:var(--ink-soft);font-weight:700;margin:0 0 .35rem}.nav__list{list-style:none;margin:0;padding:0}.nav__item a{display:block;padding:.28rem .5rem;border-radius:6px;text-decoration:none;color:var(--ink);font-size:.92rem}.nav__item a:hover{background:var(--method-bg)}.nav__item[hidden],.nav__chapter[hidden]{display:none}.nav__num{color:var(--method-accent);font-weight:600;margin-right:.35rem}.content{min-width:0}.content h1{font-size:2rem;margin:0 0 .25rem;line-height:1.2}.content h2.chapter-title{font-size:1.5rem;margin:2.5rem 0 .25rem;padding-top:1rem;border-top:2px solid var(--line)}.lead{color:var(--ink-soft);max-width:var(--maxread)}.lesson{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:1.25rem 1.4rem;margin:1.25rem 0;max-width:var(--maxread);box-shadow:0 1px 2px #141e3c0a}.lesson[hidden]{display:none}.lesson__head{margin-bottom:.9rem}.lesson__heading{font-size:1.25rem;margin:0;display:flex;align-items:baseline;gap:.4rem}.lesson__anchor{text-decoration:none;color:var(--line);font-weight:400;margin-left:-1.1rem;padding-right:.2rem}.lesson__anchor:hover,.lesson__num{color:var(--method-accent)}.lesson__dash{color:var(--ink-soft)}.lesson__problems{margin:.35rem 0 0;color:var(--ink-soft);font-size:.95rem}.layer{border-radius:8px;padding:.85rem 1rem;margin-top:.75rem;border:1px solid transparent;border-left-width:4px}.layer__label{font-size:.95rem;margin:0 0 .5rem;font-weight:700;letter-spacing:.01em}.layer__icon{margin-right:.25rem}.layer__sub{font-weight:400;color:var(--ink-soft);font-size:.82em}.layer--method{background:var(--method-bg);border-color:var(--method-line);border-left-color:var(--method-accent)}.layer--example{background:var(--example-bg);border-color:var(--example-line);border-left-color:var(--example-accent)}.layer--verify{background:var(--verify-bg);border-color:var(--verify-line);border-left-color:var(--verify-accent)}.layer--assessment{background:var(--warn-bg);border-color:var(--warn-line);border-left-color:var(--warn-accent)}.layer--assessment p{margin:0}.layer--method .layer__label{color:var(--method-accent)}.layer--example .layer__label{color:var(--example-accent)}.layer--verify .layer__label{color:var(--verify-accent)}.layer--assessment .layer__label{color:var(--warn-accent)}.layer--example .layer__grid dd{white-space:pre-wrap}.layer__grid{display:grid;grid-template-columns:max-content 1fr;gap:.3rem 1rem;margin:0}.layer__grid dt{font-weight:600;color:var(--ink-soft);font-size:.9rem}.layer__grid dd,.layer__recipe{margin:0}.path{background:#141e3c0f;padding:.1rem .4rem;border-radius:5px;display:inline-block}.key{display:inline-block;font-family:var(--font-mono);font-size:.82em;line-height:1.5;padding:.12rem .5rem;border:1px solid #c4cad8;border-bottom-width:2px;border-radius:6px;background:#fff;box-shadow:0 1px #141e3c0d;color:var(--ink);white-space:nowrap;vertical-align:baseline}.key--label{border:none;box-shadow:none;background:none;font-family:var(--font-body);font-weight:700;color:var(--ink-soft);padding:0 .15rem 0 0;font-size:.85em;text-transform:uppercase;letter-spacing:.03em}.key--type{background:var(--method-bg);border-color:var(--method-line);white-space:normal;color:var(--ink)}.kstep__arrow{color:var(--ink-soft);margin:0 .2rem;font-size:.8em}.ksteps{counter-reset:kstep;list-style:none;margin:.4rem 0 0;padding:0}.kstep{display:grid;grid-template-columns:1.75rem minmax(0,1fr);gap:.2rem .65rem;padding:.6rem 0;border-top:1px solid var(--example-line)}.kstep:first-child{border-top:none;padding-top:.2rem}.kstep__n{counter-increment:kstep;grid-row:1;grid-column:1;font-weight:700;color:var(--example-accent);font-size:.95rem}.kstep__n:before{content:counter(kstep);display:inline-grid;place-items:center;width:1.4rem;height:1.4rem;border-radius:50%;background:var(--example-bg);border:1px solid var(--example-line)}.kstep__keys{grid-row:1;grid-column:2;line-height:2}.kstep__does{grid-row:2;grid-column:2;color:var(--ink-soft);font-size:.95rem;margin-top:.1rem}.layer--verify .ksteps .kstep{border-top-color:var(--verify-line)}.layer--verify .kstep__n{color:var(--verify-accent)}.layer--verify .kstep__n:before{background:var(--verify-bg);border-color:var(--verify-line)}.keys-legend{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:.9rem 1.1rem;margin:1rem 0 0;max-width:var(--maxread);font-size:.95rem}.keys-legend p{margin:0 0 .4rem;font-weight:600}.keys-legend ul{margin:0;padding-left:1.1rem;color:var(--ink-soft)}.keys-legend li{margin:.2rem 0}.ex-line{margin:0 0 .5rem}.ex-sublabel{margin:.6rem 0 .2rem;font-size:.82rem;font-weight:700;text-transform:uppercase;letter-spacing:.03em;color:var(--example-accent)}.ex-screen{margin-top:.7rem;padding-top:.6rem;border-top:1px dashed var(--example-line)}.no-results{color:var(--ink-soft);font-style:italic;display:none}.no-results[data-show]{display:block}footer.site{max-width:var(--maxread);margin-top:3rem;padding-top:1rem;border-top:1px solid var(--line);color:var(--ink-soft);font-size:.85rem}@media (max-width: 820px){.shell{grid-template-columns:1fr}.sidebar{position:static;max-height:none;border-bottom:1px solid var(--line);padding-bottom:1rem;margin-bottom:1rem}body{font-size:17px}}