/* PCB Tools design system — content and calculator behavior remain server-rendered. */
:root{--pcb-ink:#172d3b;--pcb-muted:#61717b;--pcb-line:#dce3e6;--pcb-paper:#f4f6f5;--pcb-copper:#a8603c;--pcb-blue:#184e68;--pcb-radius:12px}
body.pcb-site{margin:0;background:#f7f8f7;color:var(--pcb-ink);font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;font-size:15px;line-height:1.65;-webkit-font-smoothing:antialiased}
.pcb-site *{box-sizing:border-box}.pcb-site a{color:var(--pcb-blue);text-underline-offset:3px}.pcb-site :focus-visible{outline:3px solid #bf7248;outline-offset:4px}.pcb-site img{max-width:100%}.pcb-site h1,.pcb-site h2,.pcb-site h3{letter-spacing:-.025em;color:var(--pcb-ink);line-height:1.3}.pcb-site h1{font-size:clamp(26px,3vw,38px);font-weight:700}.pcb-site h2{font-size:24px}.pcb-site h3{font-size:18px}.pcb-site p{line-height:1.8}.pcb-site main{scroll-margin-top:90px}.pcb-site [id]{scroll-margin-top:90px}
.pcb-site .skip-link{position:fixed;top:-100px;left:16px;z-index:10000;background:white;padding:12px}.pcb-site .skip-link:focus{top:8px}
.pcb-site .site-nav{background:#fff;color:var(--pcb-ink);border-bottom:1px solid var(--pcb-line);box-shadow:none;position:sticky;top:0;z-index:900;padding:0}
.pcb-site .nav-container{max-width:1280px;margin:auto;min-height:76px;padding:0 28px;gap:20px;display:flex;align-items:center;flex-wrap:nowrap}
.pcb-site .home-link{display:flex;align-items:center;gap:10px;color:var(--pcb-ink);font-size:21px;font-weight:750;letter-spacing:-.6px;white-space:nowrap;padding:0;margin-right:auto;text-decoration:none}.brand-light{font-weight:450}.brand-symbol{display:inline-flex;position:relative;align-items:center;justify-content:center;width:32px;height:36px;font-weight:800;font-size:24px;color:#fff;background:var(--pcb-ink);border-radius:6px}.brand-symbol>span{position:absolute;right:-5px;top:-10px;color:var(--pcb-copper);font-size:21px}
.pcb-site .nav-search-trigger{border:1px solid var(--pcb-line);border-radius:7px;background:#f7f8f8;color:#53646e;padding:8px 12px;gap:8px;font-size:12px;white-space:nowrap;order:2;margin:0}.pcb-site .nav-search-trigger kbd{border:1px solid #dce3e6;background:#fff;color:#819099;font-size:10px}.pcb-site .language-switch{order:3;margin:0}.pcb-site .lang-btn{padding:7px 9px;border:1px solid var(--pcb-line);background:#fff;color:var(--pcb-ink);font-size:12px;border-radius:6px}.pcb-site .nav-menu{gap:4px;display:flex;align-items:center}.pcb-site .nav-menu>a,.pcb-site .dropbtn{font-size:13px;font-weight:550;color:#354a57;padding:12px 10px;text-decoration:none;border-radius:5px;white-space:nowrap}.pcb-site .nav-menu a:hover,.pcb-site .dropbtn:hover{background:#eff3f4;color:#13394e}.pcb-site .dropdown-content{background:#fff;border:1px solid var(--pcb-line);border-radius:8px;box-shadow:0 18px 40px #172d3b18;max-height:68vh;overflow-y:auto;min-width:240px;z-index:910}.pcb-site .dropdown-content a{color:#354a57;font-size:13px;padding:10px 16px}.pcb-site .dropdown:focus-within .dropdown-content{display:block}.pcb-site .menu-toggle span{background:#172d3b}.pcb-site .menu-toggle{order:4}.pcb-site .site-main{max-width:1280px;padding:34px 28px 64px;margin:0 auto;min-height:65vh}
/* Bring legacy page families into the same typographic and spacing system. */
.pcb-site .site-main :is(.calc-page,.calculator-page-container,.pcb-article-page,.eng,.page-container,.container){max-width:1160px;margin-left:auto;margin-right:auto}
.pcb-site .site-main :is(.calc-page,.calculator-page-container,.eng){padding:0;background:transparent;box-shadow:none}
.pcb-site .site-main :is(.header-section,.page-header,.article-hero,.calculator-header,.hero-section){background:#edf2f3!important;color:var(--pcb-ink)!important;border:1px solid var(--pcb-line);border-radius:12px;padding:28px 32px;text-align:left;box-shadow:none;margin-bottom:24px}
.pcb-site .site-main :is(.header-section,.page-header,.article-hero,.calculator-header,.hero-section) :is(h1,h2,p,.description,.subtitle,.article-hero-copy,.article-meta){color:var(--pcb-ink)!important;text-align:left}
.pcb-site .site-main :is(.intro,.description){color:#526570;font-size:15px;max-width:100%;line-height:1.8}
.pcb-site .site-main :is(.calc-grid,.calculator-grid,.tool-grid){gap:24px;align-items:start}
.pcb-site .site-main :is(.calc-form-section,.calc-info-section,.input-panel,.result-panel,.calc-card,.calculator-card,.info-section,.article-summary,.article-section){border:1px solid var(--pcb-line);border-radius:var(--pcb-radius);background:#fff;padding:24px;box-shadow:0 2px 5px #172d3b03;min-width:0}
.pcb-site .site-main :is(.calc-form-section,.input-panel){background:#f0f4f4}
.pcb-site .site-main :is(label,.form-label){color:#374e5a;font-size:13px;font-weight:600;line-height:1.5}
.pcb-site .site-main :is(input[type=number],input[type=text],input[type=email],select,textarea){font:inherit;font-size:14px;border:1px solid #cbd6dc;border-radius:7px;background:#fff;color:#172d3b;min-height:43px;padding:10px 12px;max-width:100%;box-shadow:none}
.pcb-site .site-main :is(input,select,textarea):focus{border-color:#34708c;box-shadow:0 0 0 3px #34708c18;outline:none}
.pcb-site .site-main .form-group{margin-bottom:18px}.pcb-site .site-main :is(.btn-calc,.calculate-btn,.calc-btn,button[type=submit],.submit){background:#184e68!important;color:#fff!important;border:1px solid #184e68;border-radius:7px;font:inherit;font-weight:600;padding:12px 20px;min-height:45px;box-shadow:none;cursor:pointer}
.pcb-site .site-main :is(.result-box,.result-section){border-radius:9px;border-color:#d9e3e6;box-shadow:none}.pcb-site .site-main .result-success{background:#edf5f4;border-color:#c7dcd8;color:#173e3b}.pcb-site .site-main :is(.result-value,.rv){color:#184e68;font-variant-numeric:tabular-nums}.pcb-site .site-main :is(.formula-box,.formula){background:#f0f3f4;border:1px solid #dce4e7;border-radius:7px;color:#294654;padding:14px;font-size:14px;overflow-wrap:anywhere}.pcb-site .site-main :is(.breadcrumb,.meta){color:#76848b;font-size:12px}.pcb-site .site-main .breadcrumb a{color:#566e7b}.pcb-site .site-main .table-wrap{overflow-x:auto}.pcb-site .site-main table{font-size:13px;border-collapse:collapse;max-width:100%}.pcb-site .site-main :is(th,td){padding:12px 14px;border-color:#dce3e6}.pcb-site .site-main th{background:#edf2f4;color:#274452}.pcb-site .site-main td{line-height:1.6}.pcb-site .site-main .sheet{overflow-x:auto}.pcb-site .site-main .sheet .row{min-width:600px}.pcb-site .site-main .sheet :is(.title,.cell.header,.cell.input-label){background:#24485a}.pcb-site .site-main .sheet :is(.cell.red,.explain){background:#e9f0f1;color:#23414d}.pcb-site .site-main :is(.notice,.notice-box,.tips-box){border-radius:8px;line-height:1.7}.pcb-site .site-main details{margin-top:12px}.pcb-site .site-main summary{cursor:pointer;font-weight:600;color:#254b61}.pcb-site .site-main code{overflow-wrap:anywhere}.pcb-site .site-main .article-eyebrow{color:#5d717b;background:#dde7ea}.pcb-site .site-main .article-hero h1{font-size:32px}
/* Home */
.pcb-site .home-layout{max-width:1224px;margin:0 auto}.home-hero{display:grid;grid-template-columns:1.06fr 1fr;gap:50px;align-items:center;padding:18px 0 36px}.overline{font-size:10px!important;letter-spacing:.16em;font-weight:700;color:var(--pcb-copper);margin:0 0 20px;line-height:1.5!important}.pcb-site .home-hero h1{font-size:clamp(32px,3.5vw,48px);line-height:1.25;letter-spacing:-.04em;margin:0 0 24px}.hero-description{font-size:15px;color:#61727b;max-width:520px;margin:0 0 28px}.home-actions{display:flex;align-items:center;gap:24px;flex-wrap:wrap}.primary-action{display:inline-flex;align-items:center;justify-content:space-between;gap:36px;background:#183c50;color:#fff!important;text-decoration:none;border-radius:6px;padding:13px 20px;font-weight:600;font-size:14px}.primary-action:hover{background:#24607c}.text-action{font-size:13px;text-decoration:none;font-weight:600}.hero-footnotes{display:flex;gap:18px;flex-wrap:wrap;margin-top:32px;color:#7b888e;font-size:11px}.hero-footnotes span+span:before{content:'·';margin-right:18px}.home-visual{position:relative;margin:0;border-radius:10px;overflow:hidden;background:#e9eded}.home-visual img{width:100%;height:auto;display:block;aspect-ratio:3/2;object-fit:cover}.home-visual figcaption{padding:12px 16px;display:flex;justify-content:space-between;font-size:9px;letter-spacing:.08em;color:#76868c;background:#edf0ef}
.category-strip{display:grid;grid-template-columns:repeat(7,1fr);border-top:1px solid var(--pcb-line);border-bottom:1px solid var(--pcb-line);margin:6px 0 54px}.category-strip a{padding:20px 16px;text-decoration:none;font-size:13px;font-weight:600;position:relative}.category-strip a+a{border-left:1px solid var(--pcb-line)}.category-strip a>span{display:block;color:#87959b;font-size:10px;font-weight:400;margin-bottom:6px}.category-strip b{position:absolute;right:12px;top:19px;color:#a3afb4;font-weight:400}.category-strip a:hover{background:#edf2f2}.section-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:24px;margin-bottom:24px}.section-heading h2{font-size:28px;margin:0}.section-heading .overline{margin-bottom:12px}.section-heading>a{font-size:12px;text-decoration:none}.featured-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}.featured-tool{border:1px solid #dce3e6;background:#fff;padding:24px;border-radius:10px;text-decoration:none;transition:transform .18s,border-color .18s}.featured-tool:hover{border-color:#9fb4bd;transform:translateY(-3px)}.tool-number{color:#a06b4d;display:flex;justify-content:space-between;font-size:12px}.tool-number span{color:#8b9ba3;font-size:20px}.featured-tool h3{font-size:17px;margin:22px 0 10px}.featured-tool p{font-size:13px;color:#6e7d85;margin:0;line-height:1.7}.tool-directory{margin-top:60px}.directory-search{border:1px solid var(--pcb-line);background:#fff;border-radius:7px;padding:12px 16px;color:#687b85;font-size:12px;cursor:pointer;display:flex;gap:12px;align-items:center}.directory-search>span{font-size:22px;line-height:1}.directory-search kbd{color:#8a969c;background:#f4f6f6;padding:1px 5px;border:1px solid #dde3e6;border-radius:3px}.catalog-category{display:grid;grid-template-columns:220px 1fr;gap:40px;padding:34px 0;border-top:1px solid var(--pcb-line)}.catalog-heading h3{margin:0 0 12px;font-size:21px}.catalog-heading p{font-size:12px;color:#73828a;margin:0 0 16px}.catalog-heading>span{display:inline-block;border:1px solid #dce3e6;padding:3px 8px;border-radius:4px;font-size:10px;color:#6c7b83}.catalog-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:0 26px;align-content:start}.catalog-list>a{display:flex;gap:12px;justify-content:space-between;padding:16px 0;text-decoration:none;border-bottom:1px solid #e4e9eb;min-width:0}.catalog-list>a>span:last-child{color:#9caab0}.catalog-list strong{display:block;font-size:13px;font-weight:600;line-height:1.6}.catalog-list small{display:block;font-size:11px;color:#839098;margin-top:6px;line-height:1.65}.catalog-list a:hover strong{color:#a2603b}.home-resources{display:grid;grid-template-columns:1fr 1fr;gap:60px;background:#e9eff0;padding:40px;border-radius:12px;margin-top:40px}.home-resources h2{font-size:29px;margin:0}.home-resources p{color:#6a7e88;font-size:13px}.resource-links a{display:block;border-bottom:1px solid #cddade;padding:16px 0;text-decoration:none;font-size:14px}.resource-links small{display:block;font-size:12px;color:#6c818b;margin-top:4px}
/* Footer */
.pcb-footer{background:#162e3d;color:#e4ebee;margin-top:0;padding:48px 28px 0}.footer-inner{max-width:1224px;margin:auto;display:grid;grid-template-columns:1.5fr .75fr .85fr 1fr;gap:45px}.pcb-footer a{color:#bacbd4;text-decoration:none;font-size:12px;display:block;margin:10px 0}.pcb-footer a:hover{color:#fff}.pcb-footer h3{color:#e3edf1;font-size:12px;letter-spacing:.02em;margin:0 0 18px}.pcb-footer p{font-size:12px;color:#9bafb9;line-height:1.8}.pcb-footer small{font-size:10px;color:#839ba8;display:block;max-width:290px}.pcb-footer .footer-logo{font-size:25px;color:#fff;font-weight:750;letter-spacing:-1px;margin:0 0 15px;display:flex;gap:3px;align-items:center}.footer-logo span{font-weight:400}.footer-logo b{color:#bc825e;font-size:23px;margin-left:6px}.pcb-footer details{font-size:11px;color:#9bafb9;margin-top:14px}.pcb-footer details img{display:block;margin-top:12px}.footer-bottom{max-width:1224px;border-top:1px solid #304754;margin:35px auto 0;padding:20px 0;display:flex;justify-content:space-between;align-items:center;font-size:10px;color:#8fa5b1;letter-spacing:.04em}.footer-bottom a{margin:0;font-size:10px}
@media(max-width:1100px){.pcb-site .nav-container{gap:12px}.pcb-site .nav-menu>a,.pcb-site .dropbtn{padding:10px 7px;font-size:12px}.pcb-site .nav-search-trigger span,.pcb-site .nav-search-trigger kbd{display:none}.home-hero{gap:30px}.footer-inner{gap:25px}.catalog-category{grid-template-columns:190px 1fr;gap:30px}}
@media(max-width:850px){.pcb-site .site-main{padding:24px 20px 40px}.pcb-site .nav-container{padding:0 20px;min-height:66px}.pcb-site .home-link{font-size:20px}.pcb-site .nav-menu{display:none;position:absolute;top:66px;left:0;right:0;background:#fff;padding:18px 20px;border-bottom:1px solid var(--pcb-line);max-height:78vh;overflow:auto;flex-direction:column;align-items:stretch;z-index:905}.pcb-site .nav-menu.active{display:flex}.pcb-site .menu-toggle{display:flex}.pcb-site .nav-menu>a,.pcb-site .dropbtn{display:block;padding:12px;font-size:14px}.pcb-site .dropdown-content{position:static;box-shadow:none;max-height:300px}.home-hero{grid-template-columns:1fr;gap:28px;padding-top:10px}.hero-description{max-width:650px}.home-visual img{max-height:360px}.category-strip{grid-template-columns:repeat(3,1fr);margin-bottom:36px}.category-strip a:nth-child(4){border-left:0}.category-strip a:nth-child(n+4){border-top:1px solid var(--pcb-line)}.featured-grid{grid-template-columns:repeat(2,1fr)}.section-heading{align-items:flex-start;flex-direction:column;gap:16px}.catalog-category{grid-template-columns:1fr;gap:16px}.catalog-heading p{max-width:600px}.catalog-heading>span{display:none}.catalog-list{gap:0 20px}.home-resources{padding:28px;gap:28px}.footer-inner{grid-template-columns:1fr 1fr}.home-hero h1 br{display:block}}
@media(max-width:560px){.pcb-site{font-size:14px}.pcb-site .site-main{padding:22px 16px 36px}.pcb-site .nav-container{padding:0 16px;gap:10px}.pcb-site .nav-search-trigger{padding:8px}.pcb-site .language-switch .lang-btn{font-size:11px}.pcb-site .brand-symbol{width:27px;height:31px;font-size:20px}.pcb-site .home-link{font-size:18px;gap:9px}.pcb-site .site-main :is(.calc-grid,.calculator-grid,.tool-grid){display:grid;grid-template-columns:minmax(0,1fr)!important}.pcb-site .site-main :is(.calc-form-section,.calc-info-section,.input-panel,.result-panel,.article-summary,.article-section){padding:18px}.pcb-site .site-main :is(.header-section,.page-header,.article-hero,.calculator-header,.hero-section){padding:22px}.pcb-site .site-main .article-hero h1{font-size:27px}.pcb-site .home-hero h1{font-size:32px}.hero-description{font-size:14px}.home-actions{gap:18px}.primary-action{font-size:13px;padding:12px 16px}.hero-footnotes{gap:10px;margin-top:22px;font-size:10px}.hero-footnotes span+span:before{margin-right:10px}.home-visual figcaption{font-size:8px;padding:10px}.category-strip a{font-size:11px;padding:16px 10px}.category-strip b{right:8px;top:14px}.featured-grid{gap:10px}.featured-tool{padding:17px 14px}.featured-tool h3{font-size:15px;line-height:1.5;margin-top:16px}.featured-tool p{font-size:11px}.tool-number{font-size:10px}.section-heading h2{font-size:25px}.catalog-list{grid-template-columns:1fr}.catalog-list strong{font-size:14px}.catalog-list small{font-size:12px}.home-resources{grid-template-columns:1fr;padding:24px}.home-resources h2{font-size:25px}.footer-inner{gap:28px 22px}.footer-brand{grid-column:1/-1}.footer-supply{grid-column:1/-1}.pcb-footer{padding:36px 20px 0}.footer-bottom>span:nth-child(2){display:none}.directory-search{width:100%;justify-content:space-between}}
@media(prefers-reduced-motion:reduce){.pcb-site *{scroll-behavior:auto!important;animation:none!important;transition:none!important}}
.pcb-site .menu-toggle{flex-direction:column;align-items:center;justify-content:center;width:34px;padding:6px;gap:4px}.pcb-site .menu-toggle span{width:20px;height:2px;margin:0}
.pcb-site .site-main :is(.hub-hero,.hub-banner){background:#e9eff1!important;color:#183746!important;border:1px solid #d3dfe4;border-radius:12px;box-shadow:none;padding:32px}.pcb-site .site-main :is(.hub-hero,.hub-banner) :is(h1,p){color:#284a5b!important}.pcb-site .site-main :is(.hub-hero,.hub-banner) h1{font-size:34px}.pcb-site .site-main :is(.hub-pill,.topic-pill){background:#e1eaee;color:#456778;border-radius:5px}.pcb-site .site-main :is(.hub-topic,.topic-group,.contact-card,.hub-links,.hub-link-card){border-color:#dce4e7;border-radius:10px;box-shadow:none}.pcb-site .site-main :is(.hub-topic-card,.topic-card,.hub-banner-note){border:1px solid #dce4e7;border-radius:8px;box-shadow:none;background:#fff}.pcb-site .nav-menu a.active{background:#edf2f4;color:#184e68}.pcb-site .site-main .contact-page{max-width:1160px}
@media(max-width:560px){.pcb-site .site-main :is(.hub-hero,.hub-banner){padding:22px}.pcb-site .site-main :is(.hub-hero,.hub-banner) h1{font-size:27px}}
.pcb-site .site-main .calc-hero{background:#e9eff1;color:#25495b;border:1px solid #d5e0e6;border-radius:12px;box-shadow:none;padding:30px;text-align:left}.pcb-site .site-main .calc-hero :is(h1,h2,p){color:#25495b}.pcb-site .site-main .stat-box.primary{background:#e7f0f2;border-color:#cbdde4}.pcb-site .site-main .stat-box.primary :is(.val,.label,.stat-value,.stat-label){color:#214e64}.pcb-site .site-main .hub-hero :is(.hero-card,.hero-note,.hero-stat){box-shadow:none;border:1px solid #dce4e7}
@media(max-width:600px){.pcb-site .site-main .info-section:has(>.spacing-table){overflow-x:auto}.pcb-site .site-main .spacing-table{min-width:340px}}
/* Secondary copy remains readable on light surfaces. */
.pcb-site .catalog-list small,.pcb-site .catalog-heading p,.pcb-site .hero-footnotes{color:#61747e}.pcb-site .catalog-list small{font-size:12px}.pcb-site .home-visual figcaption{color:#526a75}