/* Approved Option 3 — light blue + orange, shared by all engineering pages. */
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#2563eb20}.status{background:#edf8f2;border-color:#cde9d9}.status.warning{color:#9a4e0c;background:#fff5eb;border-color:#f1d9bc}.result-main{border-color:#c9daf8;background:linear-gradient(120deg,#edf4ff,#fff)}.big{color:#1854c7}.note{border-color:#ea7b24}.seg:before{background:#e4edfc}.seg button[aria-pressed=true]{color:#194db2}.diagram{background:#fbfcff}.diagram svg{--board-fill:#dde9f8}.eyebrow{color:#2860b9}.article a{color:#1455c8}.article code{color:#174fb6}.card{background:#fff}.cardhead{background:#fbfcff}.metric{background:#f0f5fc}.step:hover{color:#2563eb}.toast{background:#163e78;color:#fff}.toolcard .arrow{color:#c4510a}.home-page{background:radial-gradient(ellipse at 3% 0,#e9f2ff66,transparent 55%),#f7f9fd}.home-page main{max-width:1250px;padding:30px 26px 18px}.home-page .nav{max-width:1302px;padding:10px 26px}.home-intro{padding:0 0 25px;align-items:end;gap:30px}.home-intro .eyebrow{font-size:9px;color:#647a9c;letter-spacing:2.2px}.home-intro h1{font-size:clamp(34px,4.1vw,55px);letter-spacing:-1.9px;line-height:1.12;margin:9px 0 10px;white-space:nowrap}.home-intro h1 .word-design{color:#2563eb}.home-intro h1 .word-calculate{color:#df6413}.home-intro p{font-size:14px;color:#526781}.home-search{width:325px;flex-shrink:0;position:relative;display:flex;align-items:center;margin-bottom:4px}.home-search svg{position:absolute;left:14px;width:17px;height:17px;color:#617697}.home-search input{width:100%;padding:12px 15px 12px 40px;border:1px solid #d4dff0;border-radius:11px;background:#ffffffb3;color:#183153;font-size:12px}.home-search input::placeholder{color:#64768f}.calculator-grid{gap:13px}.home-page .calc-button{display:grid;grid-template-columns:52px 1fr 18px;column-gap:15px;min-height:124px;padding:22px 20px;border:1px solid #dce6f3;border-radius:15px;align-items:center;background:#fff;box-shadow:0 4px 15px #193e6d04;animation:card-enter .48s both;animation-delay:var(--card-delay,0ms)}.calc-button:before{display:none}.home-page .calc-button:hover{border-color:#a9c6f2;transform:translateY(-4px);box-shadow:0 10px 25px #1e4e8c12}.home-page .tool-symbol{width:52px;height:58px;background:#edf4ff;border-color:transparent;color:#1755bf;border-radius:12px;margin:0}.home-page .tool-symbol svg{width:30px;height:30px;transition:transform .25s}.home-page .calc-button:hover .tool-symbol svg{transform:scale(1.08)}.home-page .calc-copy{padding:0}.home-page .calc-name{font-size:15px;font-weight:700;letter-spacing:-.4px;line-height:1.35}.home-page .calc-description{font-size:11px;color:#566e91;line-height:1.5;margin-top:7px}.home-page .calc-arrow{color:#ce550c;font-size:25px;line-height:1}.home-page .primary-entry,.home-page .training-entry,.home-page .blog-entry{min-height:145px}.home-page.light .primary-entry{position:relative;background:linear-gradient(115deg,#1c5ae4,#2367f5);color:#fff;border-color:#2367f5;box-shadow:0 5px 13px #2563eb19;overflow:hidden}.home-page.light .primary-entry:after{content:'';position:absolute;right:-20px;bottom:-35px;width:170px;height:120px;opacity:.2;background:repeating-linear-gradient(135deg,transparent 0 18px,#a5ccff 19px 21px,transparent 22px 35px);transform:skewX(-10deg);pointer-events:none}.home-page .primary-entry .calc-name,.home-page .primary-entry .calc-description,.home-page .primary-entry .calc-arrow{color:#fff}.home-page .primary-entry .tool-symbol{color:white;background:#ffffff20}.home-page.light .training-entry{background:#eef5ff;border-color:#cfdefa}.home-page.light .blog-entry{background:#fff4e9;border-color:#f6ddc5}.home-page .blog-entry .tool-symbol{background:#ffdfc2;color:#bf4a00}.home-page .calc-button:nth-child(3n+1):not(.primary-entry) .tool-symbol{color:#ce550c}.home-page .home-bottom{padding:19px 0 14px;border-color:#dce6f3}.home-bottom p{font-size:10px}.home-extra-links{display:flex;gap:24px;font-size:11px;font-weight:600;color:#1754bc}.home-extra-links span{padding-left:7px;color:#c9530b}.home-resources{font-size:9px;padding-top:12px;gap:18px}.home-footer{background:#fff;border-color:#e3eaf3}.home-footer .foot{max-width:1198px}.home-footer .contact-location{font-size:9px;color:#687b95}.home-footer .footlinks{align-items:center}.home-page .nav-quote{background:#ea6c16}.search-status{padding:35px;text-align:center;color:#52657f}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.concept-figure{margin:24px 0 34px;padding:20px;border:1px solid #dce5f1;border-radius:16px;background:#fff}.concept-figure img{display:block;width:100%;height:auto}.concept-figure figcaption{font-size:11px;color:#61728c;margin:12px 0 0}.reveal-illustration{animation:illustration-in .6s ease-out both}@keyframes card-enter{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:translateY(0)}}@keyframes illustration-in{from{opacity:0;transform:translateY(8px)}to{opacity:1;transform:translateY(0)}}
@media(max-width:1100px){.home-search{width:260px}.home-intro h1{font-size:43px}.home-intro p{font-size:12px}.main-nav{gap:18px}.home-page .calc-button{grid-template-columns:43px 1fr 16px;padding:19px 15px;column-gap:12px}.home-page .tool-symbol{width:43px;height:50px}.home-page .calc-name{font-size:13px}.home-page .calc-description{font-size:10px}.home-page .calc-arrow{font-size:22px}}
@media(max-width:800px){.nav,.home-page .nav{flex-wrap:wrap;min-height:74px;gap:10px;padding:10px 18px}.brand-logo{width:187px;height:50px}.menu-toggle{display:block;border:1px solid #d5e0f0;border-radius:9px;background:#fff;padding:9px 12px;color:#184685;font-size:13px;cursor:pointer}.main-nav{display:none;width:100%;padding:12px 0 5px;border-top:1px solid #e3eaf3;flex-wrap:wrap;gap:14px}.main-nav.open{display:flex}.nav .main-nav a{display:inline-block!important}.nav-quote{padding:9px 13px}.home-intro{align-items:start;flex-direction:column;gap:17px}.home-search{width:100%;max-width:460px}.home-page main{padding:23px 16px 18px}.home-intro h1{font-size:40px}.home-intro p{font-size:12px}.calculator-grid{grid-template-columns:repeat(2,minmax(0,1fr));gap:11px}.home-page .calc-button{grid-template-columns:40px 1fr 15px;min-height:136px;padding:19px 13px}.home-page .primary-entry,.home-page .training-entry,.home-page .blog-entry{min-height:140px}.home-page .calc-name{font-size:13px}.home-page .calc-description{font-size:10px}.home-page .tool-symbol{width:40px;height:46px}.home-page .tool-symbol svg{width:26px;height:26px}.home-bottom{align-items:start;flex-direction:column}.home-extra-links{gap:18px}.home-footer .foot{gap:15px}.home-footer .footlinks{gap:16px}}
@media(max-width:480px){.home-intro h1{font-size:34px;letter-spacing:-1.4px}.home-intro p{font-size:11px;line-height:1.65;max-width:330px}.home-page .calc-button{grid-template-columns:1fr 17px;align-items:start;padding:16px 13px;min-height:165px;gap:10px}.home-page .tool-symbol{grid-column:1;grid-row:1;width:38px;height:42px}.home-page .calc-copy{grid-column:1 / -1;grid-row:2}.home-page .calc-arrow{grid-column:2;grid-row:1;font-size:22px;align-self:center}.home-page .primary-entry,.home-page .training-entry,.home-page .blog-entry{min-height:170px}.home-page .calc-name{font-size:13px}.home-page .calc-description{font-size:10px;margin-top:5px}.home-extra-links{font-size:10px;gap:15px}.home-resources{gap:13px}.home-footer{padding:18px 16px}.concept-figure{padding:10px}}
@media(prefers-reduced-motion:reduce){.home-page .calc-button,.reveal-illustration{animation:none!important}.home-page .calc-button:hover,.nav-quote:hover{transform:none}.home-page .tool-symbol svg{transition:none}}
/* Override the earlier copper concept at matching specificity. */
.home-page.light .home-intro h1 .word-design{color:#2563eb}.home-page.light .home-intro h1 .word-calculate{color:#e7650d}.home-page.light .tool-symbol{color:#1855bc;background:#edf4ff;border-color:transparent}.home-page.light .calc-button:nth-child(4) .tool-symbol,.home-page.light .calc-button:nth-child(6) .tool-symbol,.home-page.light .calc-button:nth-child(10) .tool-symbol,.home-page.light .calc-button:nth-child(12) .tool-symbol{color:#ce550c}.home-page.light .primary-entry .tool-symbol{color:#fff;background:#ffffff20;border-color:#ffffff1f}.home-page.light .training-entry .tool-symbol{color:#1755bc;background:#d9e8ff}.home-page.light .blog-entry .tool-symbol{color:#c45100;background:#ffdfc2}.home-page.light .calc-button{border-color:#dce6f3}.home-page.light .primary-entry{border-color:#2563eb}.home-page.light .training-entry{border-color:#cfdefa}.home-page.light .blog-entry{border-color:#f6ddc5}
@media(max-width:480px){.home-intro h1{white-space:normal;max-width:100%;font-size:clamp(28px,8.6vw,34px);line-height:1.16}.home-intro{min-width:0}.home-intro>div{min-width:0;max-width:100%}}
.material-workspace{display:grid;grid-template-columns:330px minmax(0,1fr);gap:22px;align-items:start}.material-workspace select{display:block;width:100%;min-height:45px;padding:10px 12px;background:#f8faff;border:1px solid #cfdbed;border-radius:10px;color:#173754;font:13px Inter,system-ui,sans-serif}.material-workspace .number input{padding:11px 14px}.material-result{padding:27px}.material-recommendation{background:linear-gradient(125deg,#edf4ff,#fff);border:1px solid #cbdcf8;border-radius:14px;padding:22px}.material-recommendation h2{font-size:27px;color:#1755bf;margin:14px 0}.material-recommendation p{font-size:13px;color:#52657f}.material-result h3{margin:24px 0 12px}.material-result ul{padding-left:20px;color:#52657f;font-size:13px}.material-result li{margin:10px 0}.material-warning{padding:1px 17px 8px;background:#fff5ec;border-left:3px solid #dc6b1a;border-radius:8px}.material-compare{overflow-x:auto;margin-top:23px}.material-compare table{min-width:520px;line-height:1.65}.material-compare th{color:#173f7b}.material-compare td{vertical-align:top}.material-compare small{color:#52657f;font-size:11px}.material-compare td:first-child{width:82px;color:#be540f;font-size:10px;text-transform:uppercase}.material-steps{display:flex;gap:24px;margin-top:24px;color:#576f91;font:10px 'JetBrains Mono',monospace}.home-page.light .materials-entry{grid-column:1 / -1;min-height:92px;background:linear-gradient(100deg,#edf4ff,#fff4eb);border-color:#cbdcf4}.home-page .materials-entry .calc-description{max-width:600px}.home-page .materials-entry .calc-name{color:#164eac}.desk-note{padding:16px 20px;border:1px solid #dce6f3;border-left:3px solid #ea7b24;border-radius:10px;background:#f7faff;font-size:13px;color:#52657f}.desk-note strong{color:#183d72}.editorial-byline{font:11px 'JetBrains Mono',monospace;color:#607798;margin:14px 0 28px}.owned-article{max-width:900px;margin:32px auto}.owned-article h2{margin-top:30px}.owned-article p{color:#52657f}.owned-article ul{color:#52657f}.article-index{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:15px}.article-index .toolcard{min-height:210px}.article-index .toolcard h2{font-size:17px}.article-index .toolcard p{font-size:12px}.home-intro h1{white-space:normal!important}@media(max-width:850px){.material-workspace{grid-template-columns:1fr}.material-steps{flex-wrap:wrap;gap:13px}.article-index{grid-template-columns:repeat(2,minmax(0,1fr))}}@media(max-width:480px){.material-result{padding:18px}.material-recommendation{padding:18px}.material-recommendation h2{font-size:23px}.material-steps{font-size:9px}.article-index{grid-template-columns:1fr}.home-page.light .materials-entry{min-height:150px}.home-page .materials-entry .calc-copy{grid-column:1 / -1}}
/* Stackup workspace: scoped to preserve existing tools. */
.stack-workspace{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1.15fr);gap:24px;align-items:start}.stack-editor,.stack-preview{padding:24px}.stack-workspace .cardhead{padding:0 0 18px}.stack-workspace h2{font-size:20px;margin:0}.stack-preset-wrap>span{font-size:12px;color:#52657f}.stack-preset-wrap .actions{padding:8px 0 20px}.stack-settings{display:grid;grid-template-columns:1fr 1fr;gap:14px}.stack-settings label{font-size:12px;font-weight:600}.stack-settings label:first-child{grid-column:1/-1}.stack-workspace input,.stack-workspace select{width:100%;min-width:0;background:#fff;color:#142236;border:1px solid #bdcbe0;border-radius:9px;padding:10px;min-height:44px}.stack-workspace input:invalid{border-color:#b42318}.stack-row,.stack-editor-title{display:grid;grid-template-columns:40px minmax(0,1fr) minmax(0,140px);align-items:center;gap:10px;padding:9px 10px}.stack-editor-title{font-size:11px;color:#52657f;margin-top:18px}.stack-row{border-radius:10px;margin:4px 0}.copper-row{background:#fff2e6}.dielectric-row{background:#edf3fc}.layer-tag{font-size:12px;font-weight:700}.stack-value{display:flex;align-items:center;gap:5px}.stack-value span{font-size:11px;min-width:20px}.stack-metrics{display:grid;grid-template-columns:1fr 1fr;gap:18px}.stack-metrics strong{display:block;font:600 clamp(23px,2.5vw,34px)/1.5 'JetBrains Mono',monospace;letter-spacing:-1px;color:#174fbd}.stack-metrics small{color:#52657f}.stack-figure{margin:24px 0;background:#f7faff;border:1px solid #dce6f5;border-radius:14px;padding:12px}.stack-figure svg{width:100%;height:auto;display:block}.stack-figure svg text{font:12px Inter,sans-serif;fill:#294463}.stack-figure figcaption{font-size:11px;text-align:center;color:#52657f}.stack-check{padding:14px 16px;border-radius:10px;border-left:3px solid #2563eb;background:#edf3ff}.stack-check.review{background:#fff4e9;border-color:#b45309}.stack-check p{margin:4px 0;font-size:13px}.stack-preview .actions{padding:20px 0 0;gap:8px}.stack-next{display:flex;flex-wrap:wrap;gap:14px;font-size:12px;color:#174fbd;border-top:1px solid #dce6f5;padding-top:14px}.stack-preview{position:sticky;top:20px}.stackup-entry{border-color:#9bbcf7!important;background:#f0f6ff!important}.stack-workspace .note{font-size:12px}.stack-workspace details{margin-top:16px}.stack-workspace input:focus-visible,.stack-workspace select:focus-visible{outline:2px solid #2563eb}.stack-metrics strong{transition:color .2s}@media(max-width:850px){.stack-workspace{grid-template-columns:1fr}.stack-preview{position:static}}@media(max-width:450px){.stack-editor,.stack-preview{padding:16px}.stack-row,.stack-editor-title{grid-template-columns:28px minmax(0,1fr) 100px;gap:6px;padding:7px}.stack-workspace input,.stack-workspace select{font-size:13px;padding:8px}.stack-metrics{gap:8px}.stack-metrics strong{font-size:22px}}@media(prefers-reduced-motion:reduce){.stack-metrics strong{transition:none}}