/* Native control chrome must follow the theme. Without this, color-scheme stays
   `normal`, so browsers paint <select> popups, checkbox/radio glyphs, number
   spinners, scrollbars and focus rings with their LIGHT palette — which reads as
   black borders on dark panels. 210 of 259 pages declared nothing at all.
   html[data-theme="light"] is (0,1,1) so it also corrects any page that pins
   :root{color-scheme:dark} unconditionally. */
:root{color-scheme:dark}
html[data-theme="light"]{color-scheme:light}

:root{--text:var(--ink);--panel-bg:var(--surface-1);--accent-hover:#FF9440;--field:var(--field-bg);--surface:var(--surface-1);--surface2:var(--surface-2);--muted2:var(--muted-dim);--line2:var(--line-strong);--deep:var(--bg-deep)}
[data-theme="light"]{--accent-hover:#B8430A}
/* EngineerHub shared chrome — generated from background-radiation-calculator.html.
   Edit this file, not the pages. */

:root{--bg:#0F2A4A;--bg-deep:#0A1F38;--line:rgba(255,255,255,.09);--line-strong:rgba(255,255,255,.22);--grid-fine:rgba(255,255,255,.035);--ink:#F1F6FA;--muted:#8FB0C9;--muted-dim:#6488a3;--accent:#FF7A22;--accent-soft:rgba(255,122,34,.14);--green:#4ADE80;--yellow:#F5C542;--red:#E2504A;--mono:'IBM Plex Mono',ui-monospace,monospace;--sans:'IBM Plex Sans',system-ui,sans-serif;--field-bg:rgba(255,255,255,.09);--field-border:rgba(255,255,255,.32);--surface-1:rgba(255,255,255,.02);--surface-2:rgba(255,255,255,.035)}
[data-theme="light"]{--bg:#EEF0EE;--bg-deep:#0A1F38;--line:rgba(0,0,0,.07);--line-strong:rgba(0,0,0,.16);--grid-fine:transparent;--ink:#171C20;--muted:#4C5A63;--muted-dim:#7C8A92;--accent:#D9500A;--accent-soft:rgba(217,80,10,.09);--green:#1E7A4C;--field-bg:rgba(0,0,0,.045);--field-border:rgba(0,0,0,.22);--surface-1:rgba(0,0,0,.025);--surface-2:rgba(0,0,0,.045)}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);font-family:var(--sans);line-height:1.62;background-color:var(--bg);background-image:repeating-linear-gradient(0deg,var(--line) 0 1px,transparent 1px 80px),repeating-linear-gradient(90deg,var(--line) 0 1px,transparent 1px 80px),repeating-linear-gradient(0deg,var(--grid-fine) 0 1px,transparent 1px 16px),repeating-linear-gradient(90deg,var(--grid-fine) 0 1px,transparent 1px 16px)}a{color:inherit}.wrap{max-width:1120px;margin:auto;padding:0 32px;min-width:0}.top{padding:28px 0 0}.nav-inner{display:flex;align-items:center;justify-content:space-between;gap:16px;padding-bottom:20px;border-bottom:1px solid var(--line-strong)}.logo{display:flex;align-items:center;gap:10px;text-decoration:none;font:600 1rem var(--mono)}.logo img{display:block;width:20px;height:20px;flex:none}.logo b{color:var(--accent)}.nav-actions{display:flex;gap:12px;align-items:center}.breadcrumb{display:inline-flex;align-items:center;min-height:34px;font:.76rem var(--mono);color:var(--muted-dim);text-decoration:none}.report-btn,.icon-btn,.btn,.formula-toggle,.seg-btn{border:1px solid var(--line-strong);background:transparent;color:var(--ink);border-radius:3px;cursor:pointer}.report-btn{height:34px;padding:0 14px;font:.75rem var(--mono);color:var(--muted)}.icon-btn{width:34px;height:34px;display:grid;place-items:center;color:var(--muted)}.icon-btn svg{width:16px}.icon-sun{display:none}[data-theme="light"] .icon-sun{display:block}[data-theme="light"] .icon-moon{display:none}.page-head{padding:56px 0 34px}.eyebrow{font:.8rem var(--mono);letter-spacing:.12em;color:var(--accent);text-transform:uppercase;margin:0 0 14px}h1{font:600 clamp(1.9rem,4vw,2.75rem)/1.13 var(--mono);margin:0 0 16px}.lede{font-size:1.02rem;color:var(--muted);max-width:76ch;margin:0}.scope-note,.reading,.warning{border-left:3px solid var(--accent);background:var(--accent-soft);padding:13px 16px;color:var(--muted);margin-top:18px}.scope-note b,.reading b,.warning b{color:var(--ink);font-family:var(--mono)}.overview{border:1px solid var(--line-strong);background:var(--surface-1);padding:22px 24px;margin-bottom:28px}.overview h2,.panel h2,.sec-head{font:600 .95rem var(--mono);letter-spacing:.03em;margin:0}.overview p{color:var(--muted);margin:8px 0 0}.steps{display:grid;grid-template-columns:repeat(4,1fr);gap:1px;background:var(--line);border:1px solid var(--line);margin-top:18px}.step{background:var(--bg);padding:13px}.step b{display:block;color:var(--accent);font:.72rem var(--mono);text-transform:uppercase}.step span{font-size:.78rem;color:var(--muted)}.calc-grid{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:28px;align-items:start;padding-bottom:36px}.panel{border:1px solid var(--line-strong);background:var(--surface-1);padding:24px}.panel h2{padding-bottom:14px;border-bottom:1px solid var(--line-strong);margin-bottom:22px}.field{margin-bottom:18px;min-width:0;display:flex;flex-direction:column;height:100%}.field label{display:flex;justify-content:space-between;gap:10px;align-items:flex-start;min-height:80px;font:.78rem/1.3 var(--mono);margin-bottom:8px}.unit-label{color:var(--muted-dim);font-family:var(--sans);font-size:.72rem;text-align:right}.field input,.field select{width:100%;height:46px;flex:none;min-width:0;padding:10px 12px;border:1px solid var(--field-border);border-radius:3px;background:var(--field-bg);color:var(--ink);font:1rem var(--mono)}.field select option{color:#171C20}.field input:focus,.field select:focus{outline:none;border-color:var(--accent)}.field-hint{margin-top:6px;color:var(--muted-dim);font-size:.72rem;min-height:2.4em}.field-2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.field-3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.seg{display:flex;border:1px solid var(--line-strong);border-radius:3px;overflow:hidden;margin-bottom:20px}.seg-btn{flex:1;border:0;border-radius:0;padding:9px;font:.72rem var(--mono);color:var(--muted)}.seg-btn+.seg-btn{border-left:1px solid var(--line-strong)}.seg-btn.active{background:var(--accent);color:var(--bg-deep)}.result-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1px;background:var(--line);border:1px solid var(--line)}.result-card{background:var(--bg);padding:16px;min-width:0}.result-label{font:.66rem var(--mono);letter-spacing:.07em;text-transform:uppercase;color:var(--muted)}.result-value{font:600 1.18rem/1.25 var(--mono);margin-top:6px;overflow-wrap:anywhere}.result-value.accent{font-size:1.5rem;color:var(--accent)}.result-sub{font-size:.69rem;color:var(--muted-dim);margin-top:4px}.error{display:none;border-left:3px solid var(--red);background:rgba(226,80,74,.12);padding:11px 13px;margin-top:12px;font-size:.8rem}.error.show{display:block}.bar-chart{margin-top:18px}.bar-row{display:grid;grid-template-columns:130px 1fr 74px;gap:10px;align-items:center;margin:9px 0;font-size:.76rem}.bar-track{height:10px;background:var(--surface-2);border:1px solid var(--line);overflow:hidden}.bar-fill{height:100%;background:var(--accent)}.bar-value{text-align:right;font-family:var(--mono)}.formula-toggle{width:100%;display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 16px;margin-top:10px;border-style:dashed;color:var(--muted);font:.82rem var(--mono);text-align:left}.formula-toggle .chev{color:var(--accent);transition:.2s}.formula-toggle[aria-expanded=true] .chev{transform:rotate(180deg)}.formula-box{padding:16px 18px;border:1px dashed var(--line-strong);border-top:0;background:var(--surface-2);color:var(--muted);font-size:.85rem}.formula-box[hidden]{display:none}.formula-box b,.equation{color:var(--ink);font-family:var(--mono)}.block{margin-bottom:42px}.sec-head{margin-bottom:5px}.sec-sub{margin:0 0 16px;color:var(--muted);font-size:.86rem}.table-wrap{overflow:auto;border:1px solid var(--line-strong)}table{width:100%;border-collapse:collapse;min-width:650px}th,td{padding:9px 11px;border-bottom:1px solid var(--line);text-align:left;font-size:.8rem}th{background:var(--surface-2);color:var(--muted);font:.68rem var(--mono);text-transform:uppercase}.btn{background:var(--accent);border-color:var(--accent);color:var(--bg-deep);padding:10px 16px;font:.8rem var(--mono)}.item-list{display:grid;gap:8px;margin-top:14px}.item{display:grid;grid-template-columns:1fr auto auto;gap:10px;align-items:center;border:1px solid var(--line);padding:10px 12px}.item small{color:var(--muted)}.remove{border:0;background:none;color:var(--red);cursor:pointer}.related-links{display:flex;gap:8px;flex-wrap:wrap}.related-link{border:1px solid var(--line-strong);padding:8px 10px;text-decoration:none;font:.7rem var(--mono)}footer{border-top:1px solid var(--line-strong);padding:26px 0 40px;display:flex;justify-content:space-between;flex-wrap:wrap;gap:12px;color:var(--muted-dim);font:.74rem var(--mono)}.footer-links a{color:var(--muted-dim)}.modal-backdrop{position:fixed;inset:0;display:flex;align-items:center;justify-content:center;padding:24px;background:rgba(0,0,0,.55);z-index:100}.modal-backdrop[hidden]{display:none}.modal{width:100%;max-width:440px;background:var(--bg);border:1px solid var(--line-strong);padding:24px}.modal-head{display:flex;justify-content:space-between}.modal h3{font:600 1rem var(--mono);margin:0}.modal-close{border:0;background:none;color:var(--ink);font-size:1.3rem}.modal textarea{width:100%;min-height:110px;margin-top:12px;padding:10px;background:var(--field-bg);border:1px solid var(--field-border);color:var(--ink)}.modal-actions{text-align:right;margin-top:12px}
@media(max-width:900px){.calc-grid{grid-template-columns:1fr}.steps{grid-template-columns:repeat(2,1fr)}.field label,.field-hint{min-height:0}}@media(max-width:680px){.wrap{padding:0 18px}.page-head{padding-top:42px}.field-2,.field-3,.result-grid{grid-template-columns:1fr}.steps{grid-template-columns:1fr}.bar-row{grid-template-columns:95px 1fr 62px}.report-btn{display:none}.breadcrumb .full{display:none}.panel,.overview{padding:20px}.item{grid-template-columns:1fr auto}}

/* ---------- ENGINEERHUB HOUSE-STYLE NORMALIZATION ---------- */
html{scroll-behavior:smooth}
body{margin:0;background-color:var(--bg);background-image:repeating-linear-gradient(0deg,var(--line) 0 1px,transparent 1px 80px),repeating-linear-gradient(90deg,var(--line) 0 1px,transparent 1px 80px),repeating-linear-gradient(0deg,var(--grid-fine) 0 1px,transparent 1px 16px),repeating-linear-gradient(90deg,var(--grid-fine) 0 1px,transparent 1px 16px);color:var(--ink);font-family:var(--sans);-webkit-font-smoothing:antialiased}
[data-theme="light"] body{background-image:none}
a{color:inherit}::selection{background:var(--accent-soft);color:var(--ink)}:focus-visible{outline:2px solid var(--accent);outline-offset:3px}
.wrap{max-width:1120px;margin:0 auto;padding-left:32px;padding-right:32px}
header.top{position:static;padding:28px 0 0;border:0;background:transparent;backdrop-filter:none;box-shadow:none}
.nav-inner{min-height:0;height:auto;display:flex;align-items:center;justify-content:space-between;gap:18px;padding-top:0;padding-bottom:20px;border-bottom:1px solid var(--line-strong)}
.logo{display:flex;align-items:center;gap:10px;color:var(--ink);text-decoration:none;font-family:var(--mono);font-weight:600;font-size:1.05rem;letter-spacing:.02em;white-space:nowrap}.logo svg{flex:none}.logo b{color:var(--accent);font-weight:700}
.nav-actions{display:flex;align-items:center;gap:10px}.breadcrumb{color:var(--muted);text-decoration:none;font-family:var(--mono);font-size:.76rem;letter-spacing:.02em;white-space:nowrap}.breadcrumb:hover{color:var(--ink)}
.report-btn,.icon-btn{border:1px solid var(--line-strong);background:transparent;color:var(--muted);border-radius:3px;cursor:pointer;transition:color .15s ease,border-color .15s ease,background .15s ease}
.report-btn{height:34px;padding:0 14px;font-family:var(--mono);font-size:.76rem;letter-spacing:.04em}.icon-btn{width:34px;height:34px;display:inline-flex;align-items:center;justify-content:center;padding:0}.report-btn:hover,.icon-btn:hover{color:var(--ink);border-color:var(--muted)}.icon-btn svg{width:16px;height:16px}.icon-btn .icon-sun{display:none}[data-theme="light"] .icon-btn .icon-sun{display:block}[data-theme="light"] .icon-btn .icon-moon{display:none}
footer.wrap{border-top:1px solid var(--line-strong);color:var(--muted)}footer .footer-links a{color:var(--muted)}
@media(max-width:620px){.wrap{padding-left:18px;padding-right:18px}.breadcrumb .full,.report-btn{display:none}}


/* Unit system control */
.panel h2.with-units{display:flex;justify-content:space-between;align-items:center;gap:14px;flex-wrap:wrap}
.unit-toggle{display:inline-flex;border:1px solid var(--line-strong);border-radius:3px;overflow:hidden;flex:none}
.unit-btn{border:0;background:transparent;color:var(--muted);font-family:var(--mono);font-size:.70rem;padding:7px 10px;cursor:pointer}
.unit-btn+.unit-btn{border-left:1px solid var(--line-strong)}
.unit-btn.active{background:var(--accent);color:var(--bg-deep)}
@media(max-width:680px){.panel h2.with-units{align-items:flex-start}.unit-toggle{width:100%}.unit-btn{flex:1}}

/* --- tokens referenced across the site but never defined; aliased so nothing renders blank --- */
:root{--panel-bg:var(--surface-1);--accent-hover:#FF9440;--field:var(--field-bg);--surface:var(--surface-1);--surface2:var(--surface-2);--muted2:var(--muted-dim);--line2:var(--line-strong);--deep:var(--bg-deep)}
[data-theme="light"]{--accent-hover:#B8430A}

/* --- floating back-to-top button, now site-wide --- */
.to-top{position:fixed;right:22px;bottom:22px;z-index:60;width:42px;height:42px;border:1px solid var(--accent);border-radius:3px;background:var(--accent);color:var(--bg-deep);display:grid;place-items:center;cursor:pointer;opacity:0;visibility:hidden;transition:opacity .2s ease,visibility .2s ease}
.to-top.show{opacity:1;visibility:visible}
.to-top svg{width:20px;height:20px}
@media print{.to-top{display:none!important}}

/* --- wider working area for simulator pages --- */
.wrap-wide{max-width:1760px;margin:0 auto;padding-left:32px;padding-right:32px;min-width:0}
@media(max-width:680px){.wrap-wide{padding-left:18px;padding-right:18px}}



/* EngineerHub related-tools normalization 2026-08-19 */

/* Related resources — compact site-wide cross-links */
.eh-related-tools.wrap{
  margin-top:42px;
  margin-bottom:28px;
  padding-top:26px;
  padding-bottom:4px;
  border-top:1px solid var(--line-strong,rgba(255,255,255,.22));
}
.eh-related-head{display:flex;align-items:flex-end;justify-content:space-between;gap:16px;margin-bottom:14px}
.eh-related-kicker{font:600 10.5px/1.2 var(--mono,"IBM Plex Mono",monospace);letter-spacing:.12em;text-transform:uppercase;color:var(--accent,#ff7a22);margin-bottom:6px}
.eh-related-tools h2{margin:0;font:600 clamp(1.08rem,1.7vw,1.35rem)/1.2 var(--mono,"IBM Plex Mono",monospace);color:var(--ink,#eef5fb)}
.eh-crosslink-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:8px;align-items:stretch}
.eh-crosslink{
  box-sizing:border-box;
  width:100%;
  min-width:0;
  min-height:48px;
  margin:0;
  padding:10px 12px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:12px;
  border:1px solid var(--line-strong,rgba(255,255,255,.22));
  border-radius:3px;
  background:var(--surface-1,rgba(255,255,255,.02));
  color:var(--ink,#eef5fb);
  text-decoration:none!important;
  font:500 .80rem/1.35 var(--sans,"IBM Plex Sans",system-ui,sans-serif);
  letter-spacing:0;
  box-shadow:none;
  transform:none;
  transition:border-color .15s ease,background-color .15s ease,color .15s ease;
}
.eh-crosslink span{display:block;min-width:0;overflow-wrap:break-word;word-break:normal;hyphens:auto}
.eh-crosslink svg{display:block;width:15px;height:15px;flex:0 0 15px;fill:none;stroke:var(--accent,#ff7a22);stroke-width:1.8;stroke-linecap:round;stroke-linejoin:round}
.eh-crosslink:hover,.eh-crosslink:focus-visible{border-color:var(--accent,#ff7a22);background:var(--surface-2,rgba(255,255,255,.035));color:var(--ink,#eef5fb);text-decoration:none!important;transform:none}
.eh-crosslink:focus-visible{outline:2px solid var(--accent,#ff7a22);outline-offset:2px}
[data-theme="light"] .eh-related-tools.wrap{border-top-color:var(--line-strong,rgba(0,0,0,.16))}
[data-theme="light"] .eh-crosslink{background:var(--surface-1,rgba(0,0,0,.025));color:var(--ink,#171c20);border-color:var(--line-strong,rgba(0,0,0,.16))}
[data-theme="light"] .eh-crosslink:hover,[data-theme="light"] .eh-crosslink:focus-visible{background:var(--surface-2,rgba(0,0,0,.045));border-color:var(--accent,#d9500a);color:var(--ink,#171c20)}
@media(max-width:780px){.eh-crosslink-grid{grid-template-columns:1fr}}
@media(max-width:680px){.eh-related-tools.wrap{margin-top:34px;margin-bottom:24px;padding-top:22px}.eh-crosslink{min-height:46px;padding:10px 11px}}