@charset "UTF-8";
:root{color-scheme:light dark;--bg:#f5f1e9;--surface:#fcf8f0;--ink:#27342f;--muted:#5b655f;--line:#d8d7cb;--accent:#a44025;--button:#283f35;--on-button:#f9f4e9;--soft:#e8ecdf;--code:#253a33;--code-text:#eef1e6;--serif:Georgia,"Noto Serif SC","Songti SC",serif;--sans:"Helvetica Neue","PingFang SC","Microsoft YaHei",sans-serif;--max:1240px}
:root[data-theme="notebook"]{--bg:#eff3f1;--surface:#f8fbf8;--ink:#20323f;--muted:#52646c;--line:#ccd7d7;--accent:#12685e;--button:#233c4a;--soft:#e0e9e6;--code:#233b48}
*{box-sizing:border-box}html{scroll-behavior:smooth;scroll-padding-top:28px}body{margin:0;background:var(--bg);color:var(--ink);font-family:var(--sans);font-size:16px;line-height:1.7;-webkit-font-smoothing:antialiased}a{color:inherit;text-decoration:none}button,input,select{font:inherit}a,button,input,select{-webkit-tap-highlight-color:transparent}a:focus-visible,button:focus-visible,input:focus-visible,select:focus-visible,[tabindex]:focus-visible{outline:3px solid var(--accent);outline-offset:5px}button,a{touch-action:manipulation}button{cursor:pointer}p,h1,h2,h3{margin-top:0}p{color:var(--muted)}h1,h2,h3{line-height:1.25;overflow-wrap:anywhere}h1,h2{font-family:var(--serif);font-weight:500;letter-spacing:-.035em}h1{font-size:clamp(2.5rem,4.5vw,4.7rem);line-height:1.14}h2{font-size:clamp(1.8rem,2.8vw,2.8rem)}h3{font-size:1.2rem;font-weight:600}main,.site-header,.site-footer{width:min(var(--max),calc(100% - 80px));margin-inline:auto}.site-header{display:flex;align-items:center;justify-content:space-between;gap:24px;padding:30px 0;border-bottom:1px solid var(--line)}.wordmark{display:flex;align-items:center;gap:12px;min-width:0;font-weight:650;font-size:1.1rem;line-height:1.3}.wordmark-symbol{width:44px;height:44px;display:grid;place-items:center;background:var(--button);color:var(--on-button);font-family:var(--serif);font-size:25px;flex:none}.wordmark small{display:block;font-size:10px;letter-spacing:.06em;text-transform:uppercase;font-weight:450;color:var(--muted);margin-top:5px}.site-header nav{display:flex;align-items:center;gap:30px;font-size:14px;flex:none}.site-header nav a{padding:8px 0;border-bottom:1px solid transparent}.site-header nav a:hover,.site-header nav [aria-current]{border-color:var(--accent);color:var(--accent)}.language-switch{font-weight:600}.skip-link{position:absolute;left:24px;top:-100px;padding:10px 20px;background:var(--button);color:var(--on-button);z-index:20}.skip-link:focus{top:12px}.hero{display:grid;grid-template-columns:1.1fr 1fr;align-items:center;gap:clamp(32px,5vw,86px);padding:76px 0 84px}.hero-copy{padding-bottom:20px}.edition{display:flex;align-items:center;gap:12px;font-size:11px;letter-spacing:.07em;text-transform:uppercase;margin-bottom:32px;color:var(--muted)}.edition-line{height:1px;width:26px;background:var(--accent)}.edition span:last-child{margin-left:auto}.hero h1{max-width:650px;margin-bottom:26px}.hero-lead{font-size:clamp(1rem,1.5vw,1.15rem);line-height:1.9;max-width:620px}.hero-actions{display:flex;align-items:center;gap:24px;flex-wrap:wrap;margin-top:32px}.button{display:inline-flex;align-items:center;justify-content:space-between;gap:24px;min-height:50px;padding:12px 23px;font-size:14px;font-weight:550}.primary{background:var(--button);color:var(--on-button)}.primary:hover{background:var(--accent)}.text-link{border-bottom:1px solid var(--line);font-size:14px;padding-block:8px}.text-link:hover{color:var(--accent)}.hero-footnote{font-size:11px;color:var(--muted);margin-top:34px;display:flex;align-items:center;gap:8px}.tiny-dot{width:6px;height:6px;border-radius:50%;background:var(--accent);flex:none}.hero-tool{position:relative}.hero-tool:before{position:absolute;content:"";inset:12px -12px -12px 12px;border:1px solid var(--line);pointer-events:none}.worksheet,.checklist{position:relative;border:1px solid var(--line);background:var(--surface);padding:28px 30px}.eyebrow{font-size:10px;font-weight:600;letter-spacing:.12em;color:var(--accent);text-transform:uppercase}.tool-heading h2{font-family:var(--sans);letter-spacing:-.025em;font-weight:600;font-size:23px;margin:10px 0 7px}.tool-heading p{font-size:13px;margin-bottom:22px}.field-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:15px 12px}.field-grid label,.currency-label{display:flex;flex-direction:column;gap:6px;font-size:11px;color:var(--muted)}input[type="number"],select{width:100%;min-width:0;min-height:42px;border:1px solid var(--line);border-radius:0;padding:8px 10px;background:var(--bg);color:var(--ink);font-size:14px}input[type="number"]{appearance:textfield}input::-webkit-outer-spin-button,input::-webkit-inner-spin-button{-webkit-appearance:none;margin:0}.currency-label{margin-top:15px;max-width:145px}.tool-note{font-size:10px;line-height:1.7;margin:15px 0 0}.cost-output{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:20px;padding-top:18px;border-top:1px solid var(--line)}.cost-output>span{font-size:11px;color:var(--muted)}.cost-output output{font-family:var(--serif);font-size:32px;letter-spacing:-.04em;overflow-wrap:anywhere;max-width:75%}.form-error{font-size:12px;color:var(--accent);margin:5px 0 0;min-height:0}.form-error:empty{display:none}.principles{padding:44px 0 52px;border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.section-heading{margin-bottom:34px}.section-heading h2{margin:10px 0 14px}.section-heading p{font-size:14px;max-width:600px;margin-bottom:0}.principle-columns{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:40px}.principle-columns>div+div{border-left:1px solid var(--line);padding-left:36px}.principle-columns h3{margin:12px 0 10px;font-size:17px}.principle-columns p{font-size:13px;margin:0}.guides-section{display:grid;grid-template-columns:1fr 1.7fr;gap:70px;padding:64px 0}.guide-row{display:grid;grid-template-columns:34px 1fr 28px;gap:15px;align-items:start;padding:26px 0;border-top:1px solid var(--line)}.guide-row:last-child{border-bottom:1px solid var(--line)}.row-number{font-family:var(--serif);font-size:18px;color:var(--muted);padding-top:3px}.guide-row h3{margin:7px 0 10px;line-height:1.5;font-size:19px}.guide-row p{font-size:13px;margin:0 0 10px;line-height:1.8}.reading-time{font-size:10px;color:var(--muted)}.row-arrow{font-size:24px;transition:transform .2s ease-out}.guide-row:hover .row-arrow{transform:translate(3px,-3px);color:var(--accent)}.guide-row:hover h3{color:var(--accent)}.next-step{display:grid;grid-template-columns:1.6fr 1fr;gap:60px;background:var(--soft);padding:42px 44px;margin:10px 0 74px}.next-step h2{font-size:clamp(1.6rem,2.5vw,2.4rem);margin:12px 0 14px}.next-step p{font-size:14px;margin:0;max-width:620px}.next-links{display:flex;flex-direction:column;justify-content:center}.next-links a{padding:11px 0;border-bottom:1px solid var(--line);display:flex;justify-content:space-between;font-size:13px}.next-links a:hover{color:var(--accent)}.site-footer{border-top:1px solid var(--line);padding:30px 0 25px}.footer-top,.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px}.footer-brand{font-family:var(--serif);font-size:22px}.footer-top>span,.footer-top>a:last-child{font-size:11px;color:var(--muted)}.site-footer>p{max-width:710px;font-size:11px;margin:18px 0 26px}.footer-bottom{font-size:10px;color:var(--muted);letter-spacing:.03em}.request-label{font-size:10px;letter-spacing:.04em;padding:9px 14px;background:var(--soft);border:1px solid var(--line);border-bottom:0}.request-demo,pre{background:var(--code);color:var(--code-text);padding:18px 20px;overflow:auto;font:12px/1.8 "SFMono-Regular",Consolas,monospace;margin:0 0 18px;tab-size:2}.check-items{display:grid;gap:0}.check-items label{display:flex;align-items:flex-start;gap:10px;padding:9px 0;font-size:12px;cursor:pointer}.check-items input{width:16px;height:16px;flex:none;accent-color:var(--accent);margin:3px 0 0}.check-items input:checked+span{color:var(--muted);text-decoration:line-through}.check-footer{display:flex;align-items:center;justify-content:space-between;border-top:1px solid var(--line);margin-top:10px;padding-top:12px;font-size:11px;color:var(--muted)}.check-footer button{border:0;border-bottom:1px solid var(--line);background:transparent;color:var(--ink);padding:5px 8px;min-height:36px}.article-top{display:flex;justify-content:space-between;gap:20px;padding-top:35px;font-size:12px;color:var(--muted)}.article-top a:hover{color:var(--accent)}.article-header{max-width:1000px;margin:52px 0 50px}.article-header h1{font-size:clamp(2.2rem,4.1vw,4rem);margin:18px 0 22px;line-height:1.3}.article-header>.hero-lead{max-width:850px}.article-meta{display:flex;flex-wrap:wrap;gap:9px 28px;font-size:11px;color:var(--muted);padding-top:18px;border-top:1px solid var(--line)}.article-layout{display:grid;grid-template-columns:220px minmax(0,780px);gap:70px;border-top:1px solid var(--line);padding-top:38px}.toc{font-size:12px;align-self:start;position:sticky;top:25px}.toc ol{padding-left:18px;color:var(--muted)}.toc li{padding:5px 0}.toc a:hover{color:var(--accent)}.article-body{min-width:0}.article-body section{margin:0 0 35px}.article-body h2{font-size:27px;line-height:1.4;letter-spacing:-.02em;margin-bottom:16px}.article-body p,.article-body li{font-size:15px;line-height:1.95}.article-body ul{padding-left:22px;color:var(--muted)}.article-body li{margin-bottom:8px}.article-body pre{margin:20px 0;font-size:12px}.article-body a{text-decoration:underline;text-decoration-color:var(--line);text-underline-offset:4px;overflow-wrap:anywhere}.article-body a:hover{color:var(--accent)}.table-wrap{overflow:auto;border:1px solid var(--line);margin:20px 0}table{border-collapse:collapse;width:100%;font-size:13px}th,td{text-align:left;padding:12px 15px;border-bottom:1px solid var(--line);min-width:120px}th{background:var(--soft);font-weight:600}td{color:var(--muted)}tr:last-child td{border-bottom:0}.sources{padding-top:30px;border-top:1px solid var(--line)}.sources li,.sources a{font-size:12px}.publisher-note{background:var(--soft);padding:20px;font-size:12px!important}.related{max-width:780px;margin:65px 0 65px auto}.related h2{font-size:27px}.narrow{max-width:780px;margin-inline:auto}.article-body.narrow{margin-bottom:80px}.not-found{padding:100px 0 130px;max-width:800px}.not-found h1{margin-top:25px}.not-found p{max-width:600px;margin-bottom:30px}
@media(prefers-color-scheme:dark){:root{--bg:#1c2521;--surface:#232f28;--ink:#e9e9db;--muted:#b2bdae;--line:#435147;--accent:#e7a382;--button:#d6e2ce;--on-button:#24352b;--soft:#2b3b30;--code:#131f19;--code-text:#d7e6d5}:root[data-theme="notebook"]{--bg:#1c2931;--surface:#25353e;--ink:#e3ece8;--muted:#b0c1c5;--line:#405862;--accent:#91d5c3;--button:#c1ded7;--soft:#2a4048;--code:#13232b}.primary:hover{color:var(--on-button)}}
@media(min-width:1500px){.hero{padding-block:95px}.hero h1{font-size:4.9rem}}
@media(max-width:1000px){main,.site-header,.site-footer{width:calc(100% - 48px)}.hero{gap:32px;padding-block:55px}.worksheet,.checklist{padding:24px}.site-header nav{gap:20px}.wordmark small{max-width:200px}.guides-section{gap:35px;grid-template-columns:1fr 1.8fr}.principle-columns{gap:24px}.principle-columns>div+div{padding-left:24px}.article-layout{gap:36px;grid-template-columns:180px minmax(0,1fr)}.next-step{gap:30px;padding:32px}}
@media(max-width:760px){.site-header{padding-block:22px;gap:15px;align-items:flex-start}.wordmark{font-size:14px;gap:9px}.wordmark-symbol{width:35px;height:35px;font-size:21px}.wordmark small{max-width:170px;font-size:8px;line-height:1.5}.site-header nav{gap:14px;font-size:12px;flex-wrap:wrap;justify-content:flex-end;max-width:180px}.site-header nav a{padding:4px 0}.hero{grid-template-columns:1fr;gap:25px;padding:38px 0 55px}.hero-copy{padding:0}.hero h1{font-size:clamp(2.6rem,8.8vw,4rem);max-width:650px}.edition{margin-bottom:22px}.hero-lead{font-size:15px}.hero-actions{margin-top:24px}.hero-footnote{margin-top:24px;font-size:10px}.hero-tool{margin-right:10px}.hero-tool:before{inset:9px -9px -9px 9px}.worksheet,.checklist{padding:22px}.principle-columns{grid-template-columns:1fr;gap:22px}.principle-columns>div+div{padding:22px 0 0;border-left:0;border-top:1px solid var(--line)}.principle-columns h3{margin:8px 0}.principles{padding-block:30px}.guides-section{display:block;padding:40px 0}.section-heading{margin-bottom:25px}.section-heading h2{font-size:30px}.guide-row{gap:12px;grid-template-columns:26px 1fr 23px}.guide-row h3{font-size:18px}.next-step{display:block;padding:26px;margin-bottom:45px}.next-links{margin-top:22px}.footer-top{flex-wrap:wrap;gap:8px 18px}.footer-top span{flex-basis:100%;order:3}.site-footer>p{font-size:10px}.article-top{padding-top:25px}.article-header{margin:35px 0}.article-header h1{font-size:32px}.article-layout{display:block;padding-top:25px}.toc{position:static;border-bottom:1px solid var(--line);padding-bottom:18px;margin-bottom:28px}.toc ol{display:flex;flex-wrap:wrap;gap:5px 25px;font-size:11px}.toc li{margin-left:4px}.article-body h2{font-size:24px}.article-body p,.article-body li{font-size:14px}.related{margin-block:40px}.not-found{padding:60px 0 80px}}
@media(max-width:390px){main,.site-header,.site-footer{width:calc(100% - 32px)}.site-header nav{max-width:130px;gap:6px 14px}.field-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.worksheet,.checklist{padding:18px}.wordmark small{max-width:135px}.cost-output output{font-size:28px}.hero h1{font-size:2.5rem}.footer-bottom{font-size:9px;gap:10px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*{transition:none!important}}
.hero-copy,.hero-tool{min-width:0}.request-demo{max-width:100%}
@media(max-width:760px){.hero{grid-template-columns:minmax(0,1fr)}}