:root{color-scheme:light;--paper:#fafbf8;--white:#fff;--ink:#193c36;--muted:#5b6e67;--line:#dce4db;--soft:#f0f4ed;--green:#1c6454;--deep:#153f3a;--lime:#e0ecac;--gold:#ad6a2e;--sidebar:254px;--radius:12px;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif}
*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-size:15px;line-height:1.65}button,input,textarea,select{font:inherit}button,a,input,summary{touch-action:manipulation}a{color:var(--green);text-underline-offset:3px}button{cursor:pointer}button:disabled{cursor:wait;opacity:.6}:focus-visible{outline:3px solid #a35b23;outline-offset:4px}::selection{background:#e0ecac;color:#153f3a}h1,h2,h3,h4,p{margin-top:0}h1,h2,h3{line-height:1.2;letter-spacing:-.035em}h1{font-size:clamp(2rem,4vw,3.4rem);font-weight:650}h2{font-size:1.8rem;font-weight:650}h3{font-size:1.18rem;font-weight:650}small{font-size:.78rem}.sr-only{position:absolute;width:1px;height:1px;overflow:hidden;clip:rect(0,0,0,0)}.skip-link{position:fixed;top:-100px;left:15px;z-index:100;background:white;padding:12px}.skip-link:focus{top:10px}.sidebar{width:var(--sidebar);position:fixed;inset:0 auto 0 0;background:#f0f3ec;border-right:1px solid var(--line);padding:28px 20px 18px;display:flex;flex-direction:column;overflow:auto;z-index:30}.brand{display:flex;gap:10px;align-items:center;color:var(--deep);text-decoration:none;margin-bottom:34px;font-size:21px;font-weight:750;letter-spacing:-.04em}.brand svg{width:33px;height:33px;fill:#f0f3ec;stroke:var(--deep);stroke-width:2}.brand small{display:block;font-size:8px;letter-spacing:.12em;margin-top:2px;font-weight:650}.primary-nav{display:flex;flex-direction:column;gap:5px}.primary-nav a{color:#405b50;text-decoration:none;padding:10px 12px;border-radius:6px;display:flex;align-items:center;gap:11px;font-size:13px;font-weight:550}.primary-nav a>span{width:18px;font-size:19px;line-height:1}.primary-nav a small{margin-left:auto;font-size:10px;background:#e1e8dc;border-radius:4px;padding:0 5px}.primary-nav a:hover,.primary-nav a[aria-current=page]{background:#dfe8d7;color:#153f3a}.sidebar-heading{font-size:9px;font-weight:750;letter-spacing:.15em;color:#526b4b;margin:34px 10px 12px}.week-nav details{border:0;margin:0;padding:0}.week-nav summary{padding:8px 8px;font-size:12px;list-style:none;cursor:pointer;display:flex;gap:9px;align-items:center}.week-nav summary::after{content:'⌄';margin-left:auto;color:#82917e}.week-nav summary .track-no{font-size:10px;color:#526b4b;border:1px solid #ccd7c7;border-radius:4px;width:23px;text-align:center}.week-nav .week-link{display:flex;gap:10px;padding:7px 8px 7px 20px;margin:2px 0;color:#4c6156;font-size:11.5px;text-decoration:none;border-radius:5px;line-height:1.45}.week-link .week-no{font-variant-numeric:tabular-nums;color:#526b4b}.week-link[aria-current=page]{background:#153f3a;color:white}.week-link[aria-current=page] .week-no{color:#dbe9b6}.sidebar-foot{padding:25px 10px 6px;margin-top:auto;font-size:11px;display:grid;gap:10px}.sidebar-foot a{text-decoration:none}.sidebar-foot p{margin:8px 0 0;color:#526b4b;font-size:11px}.workspace{margin-left:var(--sidebar);min-width:0}.topbar{height:75px;border-bottom:1px solid var(--line);display:flex;align-items:center;justify-content:space-between;padding:0 42px;background:rgba(250,251,248,.97);position:sticky;top:0;z-index:20;gap:16px}.breadcrumbs{font-size:12px;color:var(--muted);min-width:0;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.top-actions{display:flex;gap:13px;align-items:center}.search-button{background:transparent;border:1px solid var(--line);border-radius:6px;font-size:11px;color:var(--muted);padding:8px 12px;display:flex;align-items:center;gap:9px}.search-button>span{font-size:19px;line-height:1}kbd{font-family:inherit;font-size:10px;background:#edf1e9;border:1px solid #dde4d6;border-radius:4px;padding:0 4px}.icon-button{border:1px solid var(--line);background:transparent;color:var(--ink);border-radius:6px;width:36px;height:36px;font-size:20px;display:inline-grid;place-items:center}.mobile-only{display:none}main{padding:36px 42px 55px;max-width:1540px;margin:auto;min-height:80vh}.eyebrow{font-size:10px;font-weight:750;letter-spacing:.14em;text-transform:uppercase;color:var(--muted);margin-bottom:16px}.hero{display:grid;grid-template-columns:1.2fr 1fr;min-height:340px;background:var(--deep);color:#f5f8ed;border-radius:14px;overflow:hidden;margin-bottom:28px}.hero-copy{padding:40px}.hero .eyebrow{color:#b8ceb2}.hero h1{font-size:clamp(2.2rem,4vw,3.5rem);margin:15px 0 20px;max-width:530px}.hero p{max-width:410px;color:#d2dfcd;font-size:13px;line-height:1.8}.hero .button{background:var(--lime);color:#173c33;border-color:var(--lime);margin-top:9px}.hero-art{position:relative;display:flex;flex-direction:column;align-items:center;justify-content:center;background:radial-gradient(ellipse at center,#2e5b44 0%,transparent 65%);padding:30px 24px}.hero-art svg{width:100%;max-width:380px;height:auto;overflow:visible}.hero-art .art-caption{margin-top:20px;color:#b4cbb0;font-size:10px;letter-spacing:.06em;text-align:center}.hero-art path{stroke-dasharray:4 5;animation:flow 15s linear infinite}.hero-art svg text{font-family:inherit;fill:#dce9c6;font-size:12px}.hero-art circle{fill:#254e40;stroke:#9ab584;stroke-width:1.3}.hero-art .orbit{fill:none;stroke:#3d6450;stroke-dasharray:3 7}.hero-art .active-node{fill:#d9e8a9;stroke:#d9e8a9}.hero-art .active-text{fill:#193c36;font-weight:650}.button{display:inline-flex;align-items:center;justify-content:center;gap:9px;min-height:40px;padding:10px 17px;border:1px solid var(--green);border-radius:6px;color:#fff;background:var(--green);font-size:12px;text-decoration:none;font-weight:650}.button:hover{filter:brightness(.94)}.button.secondary{background:transparent;color:var(--ink);border-color:#c8d5c6}.button.small{padding:6px 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.lab-picture{background:#e7eff0}.lab-card:nth-child(4) .lab-picture{background:#f0eaf0}.lab-card .card-body{padding:16px}.lab-card h3{font-size:14px;margin:0 0 7px}.lab-card p{font-size:11px;line-height:1.6;color:var(--muted);margin-bottom:12px}.tag{font-size:9px;letter-spacing:.05em;text-transform:uppercase;font-weight:650;color:var(--muted)}.track-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.track-card{border:1px solid var(--line);border-radius:8px;display:flex;align-items:center;padding:18px 20px;gap:18px;text-decoration:none;color:var(--ink);background:white}.track-card:hover{border-color:#8ba582;background:#f5f8f0}.track-card .track-number{font-size:18px;color:#526b4b;font-weight:500;min-width:24px}.track-card h3{font-size:14px;margin:0 0 5px}.track-card p{font-size:11px;color:var(--muted);margin:0}.track-card .arrow{margin-left:auto;color:#66815f}.page-heading{display:flex;align-items:start;justify-content:space-between;gap:25px;margin-bottom:27px}.page-heading h1{font-size:clamp(2rem,3.7vw,2.85rem);margin:6px 0 15px}.page-heading p{color:var(--muted);max-width:730px;font-size:14px}.page-heading .eyebrow{margin:0}.tabbar{display:flex;gap:4px;border-bottom:1px solid var(--line);margin-bottom:24px;overflow:auto}.tabbar a{padding:13px 16px;font-size:12px;font-weight:600;color:var(--muted);text-decoration:none;white-space:nowrap;border-bottom:2px solid transparent}.tabbar a[aria-current=page]{color:var(--green);border-bottom-color:var(--green)}.reader-grid{display:grid;grid-template-columns:minmax(0,1fr) 195px;gap:37px}.article{min-width:0;font-size:15px;line-height:1.9;max-width:850px}.article h2{font-size:25px;margin:40px 0 18px;scroll-margin-top:98px}.article h3{font-size:20px;margin:30px 0 14px;scroll-margin-top:98px}.article h4,.article h5,.article h6{font-size:17px;margin:24px 0 12px;scroll-margin-top:98px}.article p{margin-bottom:19px}.article li{padding-left:4px;margin-bottom:9px}.article code{background:#eef1e9;padding:2px 5px;border-radius:4px;color:#325444;font-size:.88em}.article pre{background:#f0f3eb;border:1px solid #dae2d3;border-radius:8px;padding:20px;overflow:auto;line-height:1.65;font-size:12px;position:relative}.article pre code{background:none;padding:0;white-space:pre}.article pre.mermaid{background:#f5f8f0;border-color:#e0e7d9;display:flex;justify-content:center;min-height:80px}.mermaid svg{max-width:100%;height:auto}.article blockquote,.article .callout{border-left:3px solid #7b9f6a;background:#eff4e7;padding:20px 23px;margin:24px 0;border-radius:0 8px 8px 0}.callout-label{font-size:10px!important;letter-spacing:.12em;text-transform:uppercase;font-weight:750;margin-bottom:10px!important;color:#426b38}.article .pitfall{background:#f8efe3;border-left-color:#c08a4b}.article .pitfall .callout-label{color:#98612b}.article 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span{font-size:10px;text-decoration:none;border:1px solid var(--line);padding:4px 9px;border-radius:4px;background:white}.inline-experiment{border:1px solid #c9d9bc;background:#f6f9ef;border-radius:10px;padding:20px;margin-bottom:28px}.inline-experiment summary{font-size:14px;font-weight:650;cursor:pointer}.inline-experiment summary small{display:block;font-weight:400;color:var(--muted);margin-top:4px}.inline-experiment iframe{width:100%;border:0;display:block;min-height:500px}.lab-iframe{width:100%;border:0;min-height:650px}.next-lesson{display:flex;justify-content:space-between;gap:15px;padding:25px 0;border-top:1px solid var(--line);margin-top:30px}.next-lesson a{max-width:48%;font-size:12px;text-decoration:none}.next-lesson a:last-child{text-align:right;margin-left:auto}.milestone-card{margin-top:38px;padding:24px;border:1px solid var(--line);border-radius:10px;background:white}.milestone-card h2{font-size:20px;margin:0 0 12px}.milestone-card p{font-size:12px;color:var(--muted)}.milestones{display:flex;flex-wrap:wrap;gap:13px;margin:20px 0}.milestones label{font-size:12px;display:flex;gap:7px;align-items:center;background:#f2f5ec;padding:9px;border-radius:5px;cursor:pointer}.milestones input{accent-color:var(--green);width:16px;height:16px}.note-label{font-size:12px;display:block;font-weight:600;margin-bottom:8px}.note-input{width:100%;padding:12px;border:1px solid #b9cab0;border-radius:6px;min-height:90px;resize:vertical;background:#fcfdfa;color:var(--ink)}.storage-note{font-size:11px!important;color:var(--muted);margin:10px 0 0!important}.progress-strip{height:5px;background:#e6ecdf;border-radius:20px;overflow:hidden}.progress-strip span{display:block;height:100%;background:#567e43;transition:width .3s}.curriculum-track{margin:30px 0}.curriculum-track h2{font-size:21px;margin-bottom:15px}.lesson-row{display:flex;align-items:center;gap:20px;padding:20px;border:1px solid var(--line);background:white;text-decoration:none;color:var(--ink);margin-bottom:9px;border-radius:8px}.lesson-row:hover{background:#f5f8ee;border-color:#a4b494}.lesson-row .number{font-size:16px;min-width:27px;color:#526b4b}.lesson-row h3{font-size:15px;margin-bottom:7px}.lesson-row p{font-size:12px;color:var(--muted);margin:0}.lesson-row .row-state{margin-left:auto;min-width:45px;font-size:11px}.filter-row{display:flex;gap:9px;flex-wrap:wrap;margin-bottom:25px}.filter-chip{border:1px solid var(--line);background:white;font-size:12px;padding:7px 13px;border-radius:20px;color:var(--ink);text-decoration:none}.filter-chip[aria-current=true]{background:var(--deep);color:white;border-color:var(--deep)}.lab-layout{display:grid;grid-template-columns:180px minmax(0,1fr);gap:30px}.lab-menu a{display:block;border:1px solid transparent;padding:10px 12px;margin:4px 0;text-decoration:none;color:var(--muted);font-size:12px;border-radius:6px}.lab-menu a[aria-current=page]{background:#e7eedc;border-color:#d3dfc6;color:var(--deep)}.animation-card{border:1px solid var(--line);border-radius:12px;padding:28px;background:white}.animation-card h2{font-size:23px}.animation-card p{font-size:13px;color:var(--muted)}.animation-stage{display:flex;align-items:center;justify-content:space-between;gap:6px;min-height:160px;margin:20px 0}.anim-node{border:1px solid #b6cba8;border-radius:10px;padding:20px 12px;text-align:center;background:#eff5e7;flex:1;transition:background .35s,transform .35s;min-width:0}.anim-node.active{background:#dceba9;border-color:#789649;transform:translateY(-5px)}.anim-node strong{font-size:22px;display:block}.anim-node small{font-size:11px;display:block}.anim-arrow{font-size:23px;color:#89a16f}.animation-explanation{background:#f1f5e9;padding:18px;border-radius:8px;min-height:95px;font-size:13px;line-height:1.8}.control-row{display:flex;gap:10px;margin-top:22px;align-items:center;flex-wrap:wrap}.control-row label{font-size:12px}.control-row output{font-variant-numeric:tabular-nums}.control-row input[type=range]{accent-color:var(--green);max-width:180px}.code-editor{width:100%;min-height:325px;resize:vertical;background:#173b32;color:#e5efd8;border:1px solid #2d5a45;border-radius:8px;padding:20px;font:13px/1.8 ui-monospace,SFMono-Regular,Consolas,monospace;tab-size:4;white-space:pre;overflow:auto}.practice-output{background:#edf3e5;white-space:pre-wrap;overflow:auto;padding:20px;border-radius:8px;font:12px/1.8 ui-monospace,monospace;min-height:90px;max-height:440px}.practice-output.error{background:#faeee6;color:#813f21}.practice-help{border:1px solid var(--line);padding:18px;border-radius:8px;margin:23px 0}.practice-help summary{font-size:13px;font-weight:650;cursor:pointer}.practice-help p{font-size:13px;color:var(--muted);margin-top:15px}.library-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:12px}.resource-card{background:white;border:1px solid var(--line);padding:20px;border-radius:8px;color:inherit;text-decoration:none;overflow-wrap:anywhere}.resource-card h3{font-size:15px;margin-bottom:10px}.resource-card p{font-size:11px;margin:0;color:var(--muted)}.library-search{display:block;width:100%;padding:12px 15px;border:1px solid #bacab0;border-radius:6px;margin-bottom:20px;background:white}.pdf-frame{width:100%;height:78vh;border:1px solid var(--line);border-radius:8px;background:white}.workbook-notice{padding:18px;background:#eef3e7;border-left:3px solid #739a60;font-size:12px;margin-bottom:24px}.notebook-cell{margin:28px 0;padding:16px 0;border-bottom:1px solid var(--line)}.cell-label{font-size:9px!important;letter-spacing:.12em;text-transform:uppercase;color:#526b4b;font-weight:700}.code-copy{position:absolute;right:10px;top:8px;border:1px solid #cad7c2;background:#f8faf5;color:var(--muted);font-size:10px;border-radius:4px;padding:3px 8px}.site-footer{border-top:1px solid var(--line);margin:0 42px;padding:20px 0 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#a7bf93;border-radius:6px;background:white;font-size:14px}#search-results{max-height:50vh;overflow:auto}.search-help{font-size:11px;color:var(--muted);margin:12px 0}.search-result{display:block;text-decoration:none;color:var(--ink);padding:15px 10px;border-bottom:1px solid var(--line)}.search-result h3{font-size:14px;margin:0 0 6px}.search-result p{font-size:12px;margin:0;color:var(--muted)}.search-result small{font-size:9px;text-transform:uppercase;letter-spacing:.08em;color:#526b4b}mark{background:#e1ebaa;color:#193c36}.toast{position:fixed;bottom:25px;left:50%;transform:translateX(-50%);background:#153f3a;color:white;padding:12px 22px;border-radius:8px;box-shadow:0 10px 40px #153f3a30;z-index:100;font-size:12px;max-width:90vw}.focused .sidebar{display:none}.focused .workspace{margin-left:0}.focused main{max-width:1200px}.focused .reader-aside{display:none}.focused .reader-grid{display:block;max-width:850px;margin:auto}.noscript{padding:40px;background:white;position:fixed;inset:0;z-index:100}.source-grid{display:grid;gap:8px}.source-grid a{padding:12px;border:1px solid var(--line);border-radius:6px;text-decoration:none;font-family:ui-monospace,monospace;font-size:12px}.error-panel{background:#faeee5;padding:25px;border-radius:10px;color:#763a20}.error-panel p{font-size:13px}.progress-summary{display:flex;align-items:center;gap:25px;padding:25px;background:#edf3e3;border-radius:10px;margin-bottom:25px}.progress-summary strong{font-size:37px;line-height:1}.progress-summary p{font-size:12px;color:var(--muted);margin:0}.settings-row{display:flex;flex-wrap:wrap;gap:10px;margin:20px 0}.note-preview{font-size:12px;color:var(--muted);white-space:pre-wrap}.feedback-message{font-size:12px;color:#687d5a}.stagger{animation:appear .35s both}@keyframes appear{from{opacity:0;transform:translateY(7px)}to{opacity:1;transform:none}}@keyframes flow{to{stroke-dashoffset:-180}}
@media(min-width:1550px){main{padding:44px 55px}.topbar{padding:0 55px}.hero-copy{padding:45px}.hero{min-height:370px}}
@media(max-width:1180px){:root{--sidebar:220px}.sidebar{padding-left:14px;padding-right:14px}.brand{font-size:19px}main{padding:28px}.topbar{padding:0 28px}.reader-grid{grid-template-columns:minmax(0,1fr)}.reader-aside{display:none}.hero-copy{padding:30px}.hero h1{font-size:38px}.lab-grid{grid-template-columns:repeat(2,1fr)}.hero-art{padding:20px 12px}.hero{grid-template-columns:1.3fr .9fr}.dashboard-grid{grid-template-columns:1fr 1fr}.site-footer{margin:0 28px}}
@media(max-width:850px){:root{--sidebar:254px}.sidebar{transform:translateX(-100%);transition:transform .2s}.workspace{margin-left:0}.mobile-only{display:inline-grid}.menu-open .sidebar{transform:translateX(0)}#close-menu{position:absolute;right:10px;top:75px}#menu-backdrop:not([hidden]){position:fixed;inset:0;background:#102a2180;z-index:25}.topbar{padding:0 20px;height:65px;gap:12px}.top-actions{margin-left:auto}.breadcrumbs{font-size:11px}.search-button{font-size:0;gap:0;border:0;padding:6px}.search-button span{font-size:23px}.search-button kbd{display:none}main{padding:25px 20px}.hero{min-height:300px}.hero h1{font-size:38px}.hero-copy{padding:28px}.hero p{font-size:12px}.lab-layout{grid-template-columns:1fr;gap:15px}.lab-menu{display:flex;overflow:auto;gap:5px;white-space:nowrap}.lab-menu a{padding:8px 12px;margin:0}.site-footer{margin:0 20px}.tabbar a{padding:12px}.article h2{scroll-margin-top:85px}.hero-art .art-caption{font-size:9px}}
@media(max-width:560px){body{font-size:14px}.hero{grid-template-columns:1fr}.hero-copy{padding:27px}.hero h1{font-size:38px;margin:12px 0 18px}.hero-art{padding:0 28px 25px}.hero-art svg{max-width:270px;max-height:150px}.hero-art .art-caption{margin-top:8px}.dashboard-grid{grid-template-columns:1fr}.first-card{min-height:190px}.stats-row{gap:10px 18px;font-size:10px}.stats-row strong{font-size:14px}.track-grid,.library-grid{grid-template-columns:1fr}.lab-grid{gap:10px}.lab-card .card-body{padding:13px}.lab-card h3{font-size:13px}.lab-card p{font-size:10px}.lab-picture{height:95px}.page-heading{display:block}.page-heading h1{font-size:31px}.page-heading>.button{margin-bottom:16px}.page-heading p{font-size:13px}.article{font-size:14px}.article h2{font-size:23px}.article pre{padding:17px 12px}.article th,.article td{padding:10px;font-size:11px}.article .callout{padding:16px}.inline-experiment{padding:14px}.lesson-row{padding:15px;gap:12px}.lesson-row h3{font-size:14px}.lesson-row p{font-size:11px}.lesson-row .row-state{min-width:30px;font-size:10px}.section-line h2{font-size:19px}.text-link{font-size:11px}.animation-card{padding:20px 15px}.anim-node{padding:16px 5px}.anim-node strong{font-size:18px}.anim-node small{font-size:10px}.anim-arrow{font-size:18px}.animation-stage{min-height:130px}.milestone-card{padding:18px}.milestones{gap:7px}.milestones label{font-size:11px}.site-footer{display:block}.site-footer a{display:block;margin-top:7px}.progress-summary{padding:20px;gap:18px}.progress-summary strong{font-size:30px}}
@media(prefers-reduced-motion:reduce){*,*::before,*::after{animation:none!important;transition:none!important;scroll-behavior:auto!important}}
@media print{.sidebar,.topbar,.site-footer,.reader-aside,.tabbar,.inline-experiment,.milestone-card,.next-lesson,.code-copy{display:none!important}.workspace{margin:0}main{padding:0}.reader-grid{display:block}.article{max-width:none;font-size:11pt}.article details>*{display:block}.article pre{white-space:pre-wrap}.article figure{break-inside:avoid}}

.mobile-toc{display:none}.article .equation-anchor,.article [id]{scroll-margin-top:95px}.reader-grid>.article{grid-column:1;grid-row:1}.reader-grid>.reader-aside{grid-column:2;grid-row:1}
@media(max-width:1180px){.mobile-toc{display:block;border:1px solid var(--line);border-radius:8px;padding:14px;margin-bottom:22px}.mobile-toc summary{font-weight:650;cursor:pointer}.mobile-toc nav{display:grid;margin-top:12px;gap:8px;font-size:13px}.reader-grid>.article{grid-row:auto}.reader-grid>.mobile-toc{grid-row:1}.reader-grid{gap:10px}}

/* A readable route from explanation to local notebook work. */
.source-banner,.notebook-bridge{background:#edf2e3;border:1px solid #c8d6b7;border-radius:12px;padding:24px;margin:24px 0}.source-banner.compact{padding:14px 22px}.source-banner p:last-child{margin-bottom:0}.source-banner a,.notebook-bridge a,.journey-steps a,.milestone-card a,.download-picker a:not(.button){text-decoration:underline;text-underline-offset:3px}.download-actions{display:flex;align-items:center;flex-wrap:wrap;gap:14px;margin:18px 0}.download-actions .button{white-space:normal}.download-picker{border:1px solid var(--line);border-radius:14px;padding:28px;background:var(--paper)}.download-picker label{display:block;font-weight:700;margin-bottom:8px}.download-picker select{font:inherit;border:1px solid #809485;padding:12px;border-radius:8px;background:white;color:#173e34;width:100%;max-width:650px;margin-bottom:20px}.download-picker .control-row{gap:18px}.journey-steps{display:grid;grid-template-columns:1fr 1fr;gap:24px;margin:28px 0}.journey-steps section{border:1px solid var(--line);padding:24px;border-radius:12px}.journey-number{font-family:Georgia,serif;font-size:36px;color:#4b6c3e}.journey-steps h2{margin:12px 0}.material-guide{display:grid;grid-template-columns:160px 1fr;gap:12px 20px}.material-guide dt{font-weight:700}.material-guide dd{margin:0}.setup-steps li{margin-bottom:14px}.lab-menu details{border-bottom:1px solid var(--line);padding:10px 0}.lab-menu summary{font-size:13px;font-weight:700;cursor:pointer;padding:8px}.lab-menu details a{display:block}.lab-layout>*{min-width:0}.download-picker code,.milestone-card code{overflow-wrap:anywhere}details.milestone-card>summary{cursor:pointer;font-weight:700} .source-banner a:focus-visible,.download-picker select:focus-visible{outline:3px solid #325b4a;outline-offset:4px}
@media(max-width:700px){.journey-steps{grid-template-columns:1fr}.material-guide{grid-template-columns:1fr;gap:6px}.material-guide dd{margin-bottom:10px}.download-picker{padding:18px}.download-actions{align-items:stretch;flex-direction:column}.lab-menu{max-height:260px;overflow:auto}}

.milestone-card pre{max-width:100%;overflow:auto;white-space:pre;padding:18px;border-radius:8px;background:#f1f3eb;border:1px solid #d2d9ca;font-size:13px;line-height:1.7}.milestone-card pre code{overflow-wrap:normal}