/* Engineer's toolbox: same warm light look as the PV row-spacing tool. */
.tb{--tb-ink:#1F2430;--tb-muted:#6B7280;--tb-line:#E7E9EE;--tb-acc:#E8871E;--tb-acc-d:#C2622B;--tb-acc-s:#FFF3E1;--tb-acc-b:#F5D9A8;--tb-num:#9A4E12;
  color-scheme:light;color:var(--tb-ink);background:linear-gradient(#FFF8EE 0,#F3F5F9 420px);font-family:"Inter",system-ui,-apple-system,"Segoe UI",sans-serif;font-size:15px;line-height:1.5;
  padding-block:40px 32px;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px));border-bottom:1px solid var(--tb-line)}
.tb-wrap{max-width:1040px;margin:0 auto;position:relative}
.tb-lang{position:absolute;top:0;right:0;display:flex;border:1px solid var(--tb-line);border-radius:999px;overflow:hidden;background:#fff;z-index:2}
.tb-lang button{font:600 12.5px "Inter",sans-serif;border:0;background:#fff;color:var(--tb-ink);padding:6px 12px;cursor:pointer}
.tb-lang button[aria-pressed="true"]{background:#1F2430;color:#fff}
.tb-head{text-align:center;max-width:740px;margin:0 auto 22px;padding:6px 76px 0}
.tb-eyebrow{font-size:12px;letter-spacing:.14em;text-transform:uppercase;font-weight:600;color:var(--tb-acc-d)}
.tb-sign{font-size:12.5px;font-weight:500;color:var(--tb-muted);margin-top:4px}
.tb h1{font-family:"Fraunces",Georgia,serif;font-weight:600;font-size:clamp(28px,4vw,40px);margin:10px 0 8px;color:var(--tb-ink);letter-spacing:-.01em;line-height:1.15}
.tb-sub{color:#4B5563;margin:0}
.tb-tabs{display:flex;gap:8px;flex-wrap:wrap;margin:0 0 18px}
.tb-tabs button{flex:0 0 auto;font:600 14px "Inter",sans-serif;border:1px solid var(--tb-line);background:#fff;color:var(--tb-ink);border-radius:999px;padding:8px 14px;cursor:pointer}
.tb-tabs button[aria-selected="true"]{background:#1F2430;color:#fff;border-color:#1F2430}
.tb-grid{display:grid;grid-template-columns:380px minmax(0,1fr);gap:22px;align-items:start}
.tb-card{background:#fff;border:1px solid var(--tb-line);border-radius:16px;box-shadow:0 1px 2px rgba(31,36,48,.04),0 8px 24px rgba(31,36,48,.06);padding:20px}
.tb-params{position:sticky;top:calc(env(safe-area-inset-top,0px) + 80px);max-height:calc(100vh - 110px);overflow:auto;display:flex;flex-direction:column;gap:14px}
.tb-results{display:flex;flex-direction:column;gap:22px;min-width:0}
.tb-cardtitle{font-size:11px;letter-spacing:.12em;text-transform:uppercase;color:var(--tb-muted);font-weight:600;margin-bottom:6px}
.tb-field{display:flex;flex-direction:column;gap:6px}
.tb-field label{font-weight:600;font-size:14px}
.tb-pair{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.tb-hint{font-size:12.5px;color:var(--tb-muted);margin:0}
.tb input[type=number],.tb select{font:16px "Inter",sans-serif;border:1px solid var(--tb-line);border-radius:10px;padding:9px 12px;background:#fff;color:var(--tb-ink);width:100%}
.tb select{appearance:none;-webkit-appearance:none;padding-right:34px;background-image:url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' fill='none' stroke='%236B7280' stroke-width='1.6'/%3E%3C/svg%3E");background-repeat:no-repeat;background-position:right 12px center}
.tb input.bad{border-color:#D9534F;background:#FFF5F5}
.tb-example{font:600 13px "Inter",sans-serif;border:1px solid var(--tb-acc-b);background:var(--tb-acc-s);color:var(--tb-acc-d);border-radius:999px;padding:8px 12px;cursor:pointer;align-self:flex-start}
.tb-hero{background:linear-gradient(135deg,#FFF3E1,#fff 70%);border-color:var(--tb-acc-b)}
.tb-big{font-family:"Fraunces",Georgia,serif;font-size:clamp(40px,6vw,60px);font-weight:600;color:var(--tb-num);line-height:1.05;font-variant-numeric:tabular-nums}
.tb-note{color:#4B5563;margin-top:4px;font-size:14px;min-height:1.2em}
.tb-warn{background:var(--tb-acc-s);border:1px solid var(--tb-acc-b);color:var(--tb-acc-d);border-radius:10px;font-size:13px;padding:8px 12px;margin-top:12px;white-space:pre-line}
.tb-minis{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:16px}
.tb-mini{background:#fff;border:1px solid var(--tb-line);border-radius:12px;padding:12px 14px;display:flex;flex-direction:column;gap:2px;min-width:0}
.tb-mini span{font-size:12px;color:var(--tb-muted)}.tb-mini b{font-size:18px;font-variant-numeric:tabular-nums;overflow-wrap:anywhere}
.tb-pdf{margin-top:16px;width:100%;background:#1F2430;color:#fff;border:0;border-radius:10px;padding:12px;font:700 14.5px "Inter",sans-serif;cursor:pointer}
.tb-formula{font-family:"Inter",sans-serif;font-size:13.5px;line-height:1.55;background:#FFF8EE;border:1px dashed var(--tb-acc-b);border-radius:12px;padding:12px 14px;margin:8px 0 0;white-space:pre-wrap;color:#1F2430}
.tb-svg{display:block;width:100%;height:auto}
.tb-svg text{font-family:"Inter",sans-serif}
.tb-limits{color:var(--tb-muted);font-size:12.5px;margin:0}
.tb-foot{text-align:center;color:var(--tb-muted);font-size:12.5px;margin-top:22px}
.tb-foot p{margin:0 auto;max-width:760px}
.tb-foot p+p{margin-top:6px}
.tb :focus-visible{outline:2px solid var(--tb-acc);outline-offset:2px}
.tb-print{display:none}
.tb-print-grid{display:grid;grid-template-columns:1fr 1fr;gap:8px 18px}
.tb-print-grid div{display:flex;flex-direction:column}
.tb-print-grid span{font-size:11px;color:var(--tb-muted)}
.tb-print-grid b{font-variant-numeric:tabular-nums}
@media (max-width:860px){
  .tb-grid{grid-template-columns:1fr}
  .tb-params{position:static;max-height:none;overflow:visible}
  .tb-head{padding:42px 0 0}
}
@media (max-width:380px){.tb-pair{grid-template-columns:1fr}}
@media print{
  @page{size:A4;margin:12mm}
  html,body{background:#fff!important}
  *{-webkit-print-color-adjust:exact;print-color-adjust:exact}
  body::before,header.top,.news,footer.site{display:none!important}
  .tb{background:#fff;padding:0;border:0}
  .tb-lang,.tb-tabs,.tb-params,.tb-pdf,.tb-example,.tb-foot{display:none!important}
  .tb-grid{display:block}
  .tb-results{gap:10px}
  .tb-card{box-shadow:none;break-inside:avoid}
  .tb-print{display:block}
  .tb-head{margin-bottom:8px;padding-top:0}
  .tb-big{font-size:36px}
}