@charset "UTF-8";
:root{--paper:#f7f7ef;--ink:#202c26;--green:#285948;--soft:#e8eddd;--muted:#657066;--line:#dce1d4;--white:#fffffa;--yellow:#ebdc9e;--serif:Georgia,'Noto Serif SC','Songti SC',serif;color-scheme:light;font-family:Inter,-apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Microsoft YaHei',sans-serif;color:var(--ink);background:var(--paper)}
*{box-sizing:border-box}body{margin:0}a{color:inherit;text-underline-offset:4px}button,input{font:inherit}a,button,input,summary{-webkit-tap-highlight-color:transparent}a:focus-visible,summary:focus-visible,input:focus-visible{outline:3px solid #ba9b39;outline-offset:5px}img,svg{max-width:100%;height:auto}p{line-height:1.85}h1,h2,h3,p{margin-top:0}h1,h2,h3{letter-spacing:-.035em}h1{font-size:clamp(36px,4.6vw,66px);line-height:1.15;margin-bottom:24px;font-weight:650}h2{font-size:clamp(26px,3vw,36px);line-height:1.3}h3{font-size:20px;line-height:1.4}strong{font-weight:650}::selection{background:#dce7bc}.wrap{width:min(1240px,calc(100% - 64px));margin-inline:auto}.skip-link{position:fixed;z-index:10;top:-80px;left:16px;background:var(--white);padding:12px}.skip-link:focus{top:12px}.site-head{border-bottom:1px solid var(--line);background:var(--white)}.head-inner{min-height:84px;display:flex;align-items:center;justify-content:space-between;gap:24px}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;flex-shrink:0}.brand img{width:40px;height:40px}.brand strong{font-size:24px;letter-spacing:-1px}.brand small{display:block;font-size:10px;letter-spacing:2px;color:var(--muted);margin-top:3px}.head-actions{display:flex;align-items:center;gap:28px;font-size:14px}.head-actions>a:not(.button){text-decoration:none}.button{display:inline-flex;align-items:center;justify-content:center;gap:20px;min-height:48px;background:var(--green);color:#fff;border:1px solid var(--green);padding:12px 22px;border-radius:8px;text-decoration:none;font-size:15px;font-weight:600;line-height:1.4;transition:background .15s,box-shadow .15s}.button:hover{background:#1d4536;box-shadow:0 4px 12px #234f3120}.button.light{background:#edf2e3;color:var(--green);border-color:#edf2e3}.arrow{font-size:21px;font-weight:400}.breadcrumbs{display:flex;align-items:center;gap:10px;flex-wrap:wrap;color:var(--muted);font-size:12px;padding:26px 0}.breadcrumbs a{text-decoration:none}.breadcrumbs span[aria-current]{max-width:52ch;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.hero{display:grid;grid-template-columns:1.1fr 1fr;align-items:center;gap:72px;padding:28px 0 64px}.eyebrow{display:flex;align-items:center;gap:12px;color:var(--green);font-size:11px;font-weight:650;letter-spacing:2px;text-transform:uppercase;line-height:1.6;margin-bottom:24px}.eyebrow:before{content:'';width:24px;height:2px;background:currentColor;flex-shrink:0}.hero-lead{font-size:18px;color:var(--muted);line-height:1.8;margin-bottom:28px;max-width:46ch}.hero-note{font-size:12px;color:var(--muted);margin:16px 0 0}.hero-art{padding:32px 28px 28px;background:#e8eddf;border-radius:18px;position:relative;min-width:0}.art-top{display:flex;justify-content:space-between;align-items:center;font-size:10px;letter-spacing:1.2px;text-transform:uppercase;color:var(--green);margin-bottom:20px;gap:14px}.art-top img{width:30px;height:30px}.request-paper{padding:26px;background:var(--white);border-radius:10px;box-shadow:0 7px 0 #c9d2ba66}.sample-title{display:flex;align-items:start;justify-content:space-between;gap:18px;border-bottom:1px dashed var(--line);padding-bottom:20px;margin-bottom:20px}.sample-title h2{font-size:24px;margin:0}.sample-price{font-family:var(--serif);font-size:26px;white-space:nowrap}.request-paper dl{margin:0;display:grid;gap:16px}.request-paper dt{font-size:10px;color:var(--muted);margin-bottom:4px;letter-spacing:.8px}.request-paper dd{margin:0;font-size:14px;line-height:1.7}.sample-response{margin:22px 0 0;border-left:3px solid var(--green);padding-left:14px;font-size:14px;line-height:1.7}.sample-response span{display:block;color:var(--green);font-size:11px;font-weight:600;margin-bottom:4px}.sample-label{font-size:10px;letter-spacing:.3px;color:var(--muted);margin:18px 0 0}.short-answer{background:var(--green);color:#f8f9ed;padding:30px 36px;border-radius:10px;display:grid;grid-template-columns:150px 1fr;gap:30px;align-items:start;margin-bottom:64px}.short-answer h2{font-size:12px;text-transform:uppercase;letter-spacing:1.5px;margin:6px 0 0;color:#cedcc6}.short-answer p{font-size:18px;line-height:1.8;margin:0}.article-layout{display:grid;grid-template-columns:220px minmax(0,820px);justify-content:space-between;gap:64px}.toc{align-self:start;position:sticky;top:32px;font-size:13px;border-top:1px solid var(--green);padding-top:18px}.toc strong{font-size:11px;letter-spacing:1px;display:block;margin-bottom:12px;color:var(--muted)}.toc a{display:block;text-decoration:none;color:var(--muted);padding:9px 0;line-height:1.6}.toc a:hover{color:var(--green);text-decoration:underline}.toc .all-guides{margin-top:18px;border-top:1px solid var(--line);padding-top:18px}.article-content section{scroll-margin-top:32px;margin-bottom:58px}.section-number{font-size:11px;letter-spacing:1px;color:var(--muted);display:block;margin-bottom:14px}.article-content p{font-size:17px;color:#4f5b52;max-width:75ch}.diagram-block{margin:42px 0;background:var(--white);border:1px solid var(--line);border-radius:12px;padding:24px}.diagram-block figcaption{font-size:12px;color:var(--muted);line-height:1.8;margin-top:14px}.diagram-block img{display:block;width:100%}.diagram-transcript{display:grid;grid-template-columns:repeat(3,1fr);gap:20px;padding:0;margin:20px 0 0;list-style:none}.diagram-transcript li{font-size:13px;line-height:1.7;color:var(--muted)}.diagram-transcript strong{display:block;color:var(--ink);font-size:14px;margin-bottom:5px}.checklist-block{background:#e9eedf;border-radius:12px;padding:30px}.checklist-block h2{font-size:26px}.checklist-block p{font-size:13px}.checklist{display:grid;gap:0;margin:16px 0 0;padding:0;list-style:none}.checklist li{border-top:1px solid #ced7c0}.checklist label{display:flex;gap:14px;align-items:flex-start;padding:16px 0;font-size:16px;line-height:1.7;cursor:pointer}.checklist input{width:18px;height:18px;accent-color:var(--green);flex-shrink:0;margin:5px 0 0}.checklist input:checked+span{color:#748065}.example-grid{display:grid;grid-template-columns:1fr 1fr;gap:14px}.example-card{padding:24px;background:var(--white);border:1px solid var(--line);border-radius:10px}.example-card h3{font-size:13px;color:var(--green);margin-bottom:12px;letter-spacing:0}.example-card p{font-size:15px;margin:0;line-height:1.85}.example-card.rethink{background:#f2ecdd}.example-outcome{border-left:3px solid var(--green);padding-left:20px;margin-top:24px}.example-outcome strong{display:block;font-size:13px;color:var(--green);margin-bottom:8px}.faq details{border-top:1px solid var(--line)}.faq details:last-child{border-bottom:1px solid var(--line)}.faq summary{cursor:pointer;padding:22px 32px 22px 0;font-size:18px;font-weight:600;line-height:1.5;list-style:none;position:relative}.faq summary::-webkit-details-marker{display:none}.faq summary:after{content:'+';position:absolute;right:4px;top:20px;color:var(--green);font-size:24px;font-weight:400}.faq details[open] summary:after{content:'−'}.faq details p{font-size:16px;margin:0;padding:0 20px 22px 0}.closing{background:#e8eddf;border:1px solid #d5dfc8;padding:40px;border-radius:12px;display:flex;align-items:center;justify-content:space-between;gap:24px;margin:10px 0 64px}.closing h2{font-size:28px;margin-bottom:10px}.closing p{font-size:15px;color:var(--muted);margin:0}.closing .button{flex-shrink:0;max-width:40%}.related{padding-bottom:64px}.related-title{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-bottom:24px}.related-title h2{font-size:23px;margin:0}.related-title a{font-size:13px;color:var(--green)}.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}.guide-link{display:block;border-top:1px solid var(--line);text-decoration:none;padding:20px 0}.guide-link .category{font-size:10px;letter-spacing:1px;text-transform:uppercase;color:var(--muted)}.guide-link h3{font-size:22px;margin:12px 0 16px}.guide-link p{font-size:14px;color:var(--muted);margin:0}.guide-link:hover h3{color:var(--green);text-decoration:underline;text-underline-offset:5px}.site-foot{background:var(--white);border-top:1px solid var(--line);padding:28px 0}.foot-inner{display:flex;align-items:center;justify-content:space-between;gap:24px;color:var(--muted);font-size:12px}.foot-links{display:flex;flex-wrap:wrap;gap:24px}.foot-links a{text-decoration:none}.directory-hero{padding:42px 0 48px;max-width:800px}.directory-hero h1{max-width:16ch}.directory-hero p{font-size:20px;color:var(--muted);max-width:62ch}.directory-categories{display:flex;flex-wrap:wrap;gap:12px;border-top:1px solid var(--line);padding:24px 0 50px}.directory-categories a{border:1px solid var(--line);background:var(--white);padding:10px 18px;border-radius:30px;text-decoration:none;font-size:14px}.directory-section{padding-bottom:54px;scroll-margin-top:28px}.directory-section>h2{font-size:26px;display:flex;align-items:center;gap:16px}.directory-section>h2 span{font-size:11px;color:var(--muted);font-family:inherit;letter-spacing:1px}.directory-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px}.directory-grid .guide-link{background:var(--white);border:1px solid var(--line);padding:26px;border-radius:10px}.directory-grid .guide-link h3{font-size:22px}.directory-intro{display:flex;gap:20px;align-items:center;font-size:13px;color:var(--muted)}
@media(min-width:1600px){.wrap{width:min(1320px,calc(100% - 96px))}.hero{gap:100px}}
@media(max-width:1050px){.hero{gap:32px;grid-template-columns:1fr 1fr}h1{font-size:44px}.hero-art{padding:22px}.request-paper{padding:22px}.sample-price{font-size:23px}.article-layout{grid-template-columns:170px minmax(0,1fr);gap:36px}.head-actions{gap:18px}.directory-grid{grid-template-columns:1fr 1fr}}
@media(max-width:760px){.wrap{width:calc(100% - 40px)}.head-inner{min-height:70px;gap:14px}.brand strong{font-size:21px}.brand img{width:34px;height:34px}.head-actions{gap:15px}.head-actions>.directory-link{display:none}.head-actions>.button{padding:8px 12px;font-size:12px;min-height:38px;gap:8px}.head-actions>.button .arrow{display:none}.head-actions>a:not(.button){font-size:12px}.breadcrumbs{font-size:11px;padding:20px 0}.breadcrumbs span[aria-current]{max-width:25ch}.hero{grid-template-columns:1fr;padding:20px 0 36px;gap:32px}.hero h1{font-size:40px;max-width:16ch}.hero-lead{font-size:17px;max-width:none}.eyebrow{margin-bottom:18px;font-size:10px}.hero-art{padding:22px}.short-answer{display:block;padding:24px;margin-bottom:36px}.short-answer h2{margin-bottom:14px}.short-answer p{font-size:16px}.article-layout{display:block}.toc{position:static;margin-bottom:38px;display:grid;grid-template-columns:1fr 1fr;column-gap:20px}.toc strong{grid-column:1/-1}.toc a{font-size:12px;padding:8px 0}.toc .all-guides{margin-top:0;border:0;padding-top:8px}.article-content p{font-size:16px}.article-content section{margin-bottom:38px}.article-content h2{font-size:28px}.diagram-block{padding:16px;margin:30px 0}.diagram-transcript{grid-template-columns:1fr;gap:12px}.diagram-transcript li{display:flex;gap:12px}.diagram-transcript strong{min-width:95px}.checklist-block{padding:24px}.checklist label{font-size:15px}.example-grid{grid-template-columns:1fr}.example-card{padding:20px}.faq summary{font-size:17px}.closing{display:block;padding:28px;margin-bottom:40px}.closing .button{max-width:100%;margin-top:24px}.closing h2{font-size:26px}.related{padding-bottom:38px}.related-title{align-items:start}.related-grid{grid-template-columns:1fr;gap:0}.guide-link h3{font-size:21px}.foot-inner{display:block}.foot-links{gap:18px;margin-top:20px;font-size:11px}.directory-hero{padding:20px 0 30px}.directory-hero h1{font-size:40px}.directory-hero p{font-size:17px}.directory-grid{grid-template-columns:1fr;gap:16px}.directory-categories{padding:20px 0 34px;gap:8px}.directory-categories a{padding:9px 13px;font-size:13px}.directory-intro{display:block}.directory-intro span{display:block;margin-top:8px}}
@media(prefers-reduced-motion:reduce){*,*:before,*:after{transition:none!important;scroll-behavior:auto!important}}
/* Keep the sample card and the visual walkthrough readable on narrow screens. */
.sample-title{flex-wrap:wrap}.sample-title h2{min-width:0;overflow-wrap:anywhere}
@media(min-width:761px){.diagram-transcript{display:none}}
@media(max-width:760px){.brand small{display:none}.diagram-block img{display:none}.diagram-transcript{counter-reset:step;gap:0;margin:0}.diagram-transcript li{position:relative;display:block;padding:4px 0 25px 48px;min-height:88px}.diagram-transcript li:before{counter-increment:step;content:'0' counter(step);position:absolute;left:0;top:0;background:var(--green);color:#fff;border-radius:50%;width:30px;height:30px;display:grid;place-items:center;font-size:12px}.diagram-transcript li:not(:last-child):after{content:'';position:absolute;left:14px;top:36px;bottom:4px;width:2px;background:#d2ddc5}.diagram-transcript li:last-child{padding-bottom:0}.diagram-transcript strong{font-size:16px;margin-bottom:6px}.diagram-transcript li span{font-size:14px;line-height:1.8}.sample-title h2{font-size:22px}}
@media(max-width:480px){.head-actions>.button{display:none}.head-actions{gap:0}.brand{gap:9px}.sample-title{gap:10px}.head-inner{min-height:64px}}
h1,h2,h3{text-wrap:balance}html[lang="zh-CN"] .hero h1{font-size:clamp(36px,4.1vw,59px);line-height:1.25}
@media(max-width:760px){html[lang="zh-CN"] .hero h1{font-size:36px}}