.chapter-one-page{background:var(--paper)}.chapter-one-hero{padding-block:96px 72px;border-bottom:1px solid var(--line)}.chapter-one-hero h1{max-width:940px;margin:24px 0;font-size:clamp(50px,6.2vw,84px);line-height:.95;letter-spacing:-.065em}.chapter-one-hero h1 em{color:var(--violet-deep);font-style:normal}.chapter-one-hero>p:last-child{max-width:760px;margin:0;color:var(--muted);font-size:18px;line-height:1.7}.chapter-one-layout{display:grid;grid-template-columns:280px minmax(0,780px);gap:90px;align-items:start;padding-block:78px 105px}.chapter-one-nav{position:sticky;top:88px;border-top:1px solid var(--line)}.chapter-one-nav>div{display:grid;gap:5px;padding:22px 0}.chapter-one-nav>div small{color:var(--violet-deep);font:750 9px var(--font-geist-mono);letter-spacing:.14em}.chapter-one-nav>div strong{font-size:22px}.chapter-one-nav ol{margin:0;padding:0;list-style:none;border-bottom:1px solid var(--line)}.chapter-one-nav li{border-top:1px solid var(--line)}.chapter-one-nav a{display:grid;grid-template-columns:32px 1fr;gap:12px;padding:17px 10px;color:inherit;text-decoration:none}.chapter-one-nav a>span{padding-top:2px;color:#9296a0;font:10px var(--font-geist-mono)}.chapter-one-nav a div{display:grid;gap:4px}.chapter-one-nav a strong{font-size:13px}.chapter-one-nav a small{color:var(--muted);font-size:10px;line-height:1.35}.chapter-one-nav li.active a{background:var(--ink);color:white}.chapter-one-nav li.active a small,.chapter-one-nav li.active a span{color:var(--lime)}.chapter-one-article{min-width:0}.chapter-one-article>section{padding:0 0 68px;margin-bottom:68px;border-bottom:1px solid var(--line)}.chapter-one-article h2{margin:0 0 20px;font-size:clamp(32px,4vw,48px);line-height:1.03;letter-spacing:-.045em}.chapter-one-article h3{margin:34px 0 12px;font-size:20px}.chapter-one-article li,.chapter-one-article p{color:#555a68;font-size:16px;line-height:1.78}.chapter-one-article .terminal{margin-top:25px}.chapter-one-lead>span{display:inline-block;margin-bottom:22px;padding:7px 10px;background:var(--ink);color:var(--lime);font:10px var(--font-geist-mono)}.chapter-one-note{margin-top:30px;padding:22px 25px;border-left:4px solid var(--violet);background:#ebe9ff}.chapter-one-note p{margin:7px 0 0}.chapter-one-concepts{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}.chapter-one-choices>div,.chapter-one-concepts>div{padding:24px;border:1px solid var(--line);background:#fff}.chapter-one-concepts span{display:block;margin-bottom:30px;color:var(--violet-deep);font:700 10px var(--font-geist-mono)}.chapter-one-choices p,.chapter-one-concepts p{margin:9px 0 0;font-size:13px}.chapter-one-downloads{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-bottom:26px}.chapter-one-downloads a{display:grid;gap:9px;min-height:170px;padding:22px;border:1px solid var(--line);background:#fff;color:inherit;text-decoration:none}.chapter-one-downloads a:hover{border-color:var(--violet)}.chapter-one-downloads span{color:var(--violet-deep);font:10px var(--font-geist-mono)}.chapter-one-downloads code{overflow-wrap:anywhere;color:var(--muted);font-size:9px}.chapter-one-downloads b{align-self:end;color:var(--violet-deep);font-size:11px}.chapter-one-output{margin-top:18px;padding:20px 22px;background:var(--ink);color:#d8dae2;font:12px/1.8 var(--font-geist-mono)}.chapter-one-output span{color:var(--lime)}.chapter-one-choices{display:grid;grid-template-columns:1fr 1fr;gap:12px}.chapter-one-choices>div{display:grid;gap:10px}.chapter-one-choices code{width:max-content;padding:5px 7px;background:#eeedf7;color:var(--violet-deep);font-size:11px}.chapter-one-code-pair{display:grid;grid-template-columns:1fr 1fr;gap:18px}.chapter-one-code-pair small{color:var(--violet-deep);font:750 9px var(--font-geist-mono);letter-spacing:.1em}.chapter-one-code-pair .terminal{height:calc(100% - 18px);margin-top:9px}.chapter-one-troubles{border:1px solid var(--line);background:#fff}.chapter-one-troubles>div{display:grid;grid-template-columns:220px 1fr;gap:24px;padding:22px;border-top:1px solid var(--line)}.chapter-one-troubles>div:first-child{border:0}.chapter-one-troubles code{color:var(--violet-deep);font-size:11px}.chapter-one-troubles p{margin:0;font-size:13px}.chapter-one-exercise{padding:38px!important;background:var(--violet);color:white;border:0!important}.chapter-one-exercise>span{color:var(--lime);font:750 9px var(--font-geist-mono);letter-spacing:.12em}.chapter-one-exercise h2{margin-top:12px}.chapter-one-exercise p{color:#f0efff}.chapter-one-pager{display:flex;justify-content:space-between;gap:30px}.chapter-one-pager a{color:var(--violet-deep);font-weight:750;text-decoration:none}.chapter-one-kicker{margin:0 0 14px!important;color:var(--violet-deep)!important;font:750 9px/1.3 var(--font-geist-mono)!important;letter-spacing:.13em}.chapter-one-flow{display:grid;grid-template-columns:1fr auto 1fr auto 1fr;gap:12px;align-items:stretch;margin:30px 0}.chapter-one-flow>div{display:grid;gap:9px;min-height:130px;padding:20px;border:1px solid var(--line);background:#fff}.chapter-one-flow>div>span{color:var(--violet-deep);font:700 10px var(--font-geist-mono)}.chapter-one-flow>div p{margin:0;font-size:12px}.chapter-one-flow>b{align-self:center;color:var(--violet-deep)}.chapter-one-compare{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:28px 0}.chapter-one-compare>div{padding:25px;border:1px solid var(--line);background:#fff}.chapter-one-compare p{margin:8px 0 0;font-size:13px}.chapter-one-method{display:grid;gap:0;margin:28px 0 0;padding:0;list-style:none;border:1px solid var(--line);background:#fff}.chapter-one-method li{display:grid;grid-template-columns:190px 1fr;gap:25px;padding:18px 20px;border-top:1px solid var(--line)}.chapter-one-method li:first-child{border:0}.chapter-one-method strong{color:var(--violet-deep);font-size:13px}.chapter-one-method span{color:#555a68;font-size:13px;line-height:1.6}.chapter-one-scenarios{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:28px}.chapter-one-scenarios>div{display:grid;grid-template-columns:1fr auto;gap:14px;align-items:center;padding:20px;border:1px solid var(--line);background:#fff}.chapter-one-scenarios strong{font-size:13px}.chapter-one-scenarios code{padding:6px 8px;background:var(--ink);color:var(--lime);font-size:10px}.chapter-one-warning{margin-top:28px;padding:24px;border-top:3px solid #d88b24;background:#fff1d9}.chapter-one-warning p{margin:8px 0 0}.chapter-one-summary{padding:34px!important;border:1px solid var(--line)!important;background:#ecebe4}.chapter-one-summary h2{font-size:30px}.chapter-one-summary ul{display:grid;gap:10px;margin:24px 0 0;padding:0;list-style:none}.chapter-one-summary li{position:relative;padding-left:27px;font-size:14px}.chapter-one-summary li:before{content:"✓";position:absolute;left:0;color:var(--violet-deep);font-weight:800}.chapter-one-checkpoint{padding:34px!important;border:1px solid var(--violet)!important;background:#efedff}.chapter-one-checkpoint h2{font-size:30px}.chapter-one-checkpoint details{margin-top:24px;border:1px solid #cbc5f4;background:#fff}.chapter-one-checkpoint summary{cursor:pointer;padding:17px 19px;color:var(--violet-deep);font-weight:750}.chapter-one-checkpoint details p{margin:0;padding:0 19px 19px;font-size:14px}@media(max-width:900px){.chapter-one-layout{grid-template-columns:1fr;gap:50px}.chapter-one-nav{position:static}.chapter-one-nav ol{display:grid;grid-template-columns:1fr 1fr}}@media(max-width:640px){.chapter-one-hero{padding-block:65px 52px}.chapter-one-layout{padding-block:48px 75px}.chapter-one-choices,.chapter-one-code-pair,.chapter-one-compare,.chapter-one-concepts,.chapter-one-downloads,.chapter-one-flow,.chapter-one-nav ol,.chapter-one-scenarios{grid-template-columns:1fr}.chapter-one-flow>b{transform:rotate(90deg);justify-self:center}.chapter-one-method li,.chapter-one-troubles>div{grid-template-columns:1fr;gap:9px}.chapter-one-scenarios>div{grid-template-columns:1fr}.chapter-one-article>section{padding-bottom:48px;margin-bottom:48px}.chapter-one-exercise{margin-inline:calc(var(--pad) * -1);padding-inline:var(--pad)!important}.chapter-one-pager{align-items:flex-start;flex-direction:column}}