/* Hydrofire Flue Calculator — staff test tool. Hydrofire blue, light/dark. */
:root{
  --bg:#f5f7fa; --panel:#fff; --fg:#1b2430; --muted:#5d6b7b; --line:#d8e0e9;
  --accent:#2675BB; --accent-fg:#fff; --soft:#e7f0f9;
  --err:#a02c2c; --err-bg:#fbe9e7; --warn:#7a5410; --warn-bg:#fbf1dc;
  font-family:"Segoe UI",system-ui,-apple-system,Roboto,Arial,sans-serif;
}
@media (prefers-color-scheme: dark){:root{
  --bg:#10161d; --panel:#18212b; --fg:#e4eaf1; --muted:#9aa9b9; --line:#2b3947;
  --accent:#5b9bd5; --accent-fg:#0d1620; --soft:#1d2d3d;
  --err:#f2a49c; --err-bg:#3a1c1a; --warn:#e9c77f; --warn-bg:#33280f; color-scheme:dark}}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:var(--fg);font-size:15px;line-height:1.5}
a{color:var(--accent)}
.wrap{max-width:1200px;margin:0 auto;padding-left:max(16px,env(safe-area-inset-left,0px));padding-right:max(16px,env(safe-area-inset-right,0px))}
.top{background:var(--accent);color:var(--accent-fg)}
.top .wrap{display:flex;flex-wrap:wrap;gap:8px 16px;justify-content:space-between;align-items:center;padding-block:12px}
.top a,.top .muted{color:var(--accent-fg);opacity:.9}
.grid{display:grid;grid-template-columns:minmax(0,420px) minmax(0,1fr);gap:20px;padding-block:20px 48px;align-items:start}
@media (max-width:860px){.grid{grid-template-columns:minmax(0,1fr)}}
.panel{background:var(--panel);border:1px solid var(--line);border-radius:8px;padding:18px;display:flex;flex-direction:column;gap:8px;min-width:0}
h1,h2{margin:0}
h2{font-size:1.05rem;margin-top:10px}
h2:first-child,.panel>h2:first-of-type{margin-top:0}
label{font-size:13px;color:var(--muted)}
input,select,button{font:inherit;color:inherit}
input,select{width:100%;padding:8px 10px;border:1px solid var(--line);border-radius:6px;background:var(--bg)}
input[readonly],select:disabled{opacity:.75}
input:focus-visible,select:focus-visible,button:focus-visible,summary:focus-visible{outline:2px solid var(--accent);outline-offset:2px}
button{margin-top:10px;padding:10px 14px;border:0;border-radius:6px;background:var(--accent);color:var(--accent-fg);font-weight:600;cursor:pointer}
.row2{display:grid;grid-template-columns:1fr 1fr;gap:10px}
.measures{display:grid;grid-template-columns:1fr;gap:8px}
.measure label b{color:var(--accent);margin-right:4px}
.diagram{width:100%;max-width:100%;border:1px solid var(--line);border-radius:6px;background:#fff}
.muted{color:var(--muted);margin:0}
.error{background:var(--err-bg);color:var(--err);padding:10px 12px;border-radius:6px;margin:0}
.warn{background:var(--warn-bg);color:var(--warn);padding:8px 12px;border-radius:6px;margin:0}
.tbl{overflow-x:auto}
table{border-collapse:collapse;width:100%;font-size:14px}
th,td{text-align:left;padding:7px 8px;border-bottom:1px solid var(--line);vertical-align:top}
th{font-size:12px;text-transform:uppercase;letter-spacing:.04em;color:var(--muted)}
tfoot td{font-weight:700;border-bottom:0}
.num{text-align:right;white-space:nowrap;font-variant-numeric:tabular-nums}
.sku{font-family:Consolas,"Cascadia Mono",monospace;font-size:13px;white-space:nowrap}
.tag{font-size:11px;background:var(--warn-bg);color:var(--warn);padding:1px 6px;border-radius:3px;white-space:nowrap}
tr.inactive td{opacity:.7}
details{margin-top:8px}
summary{cursor:pointer;color:var(--accent)}
.steps td{font-size:13px}
body.login{display:grid;place-items:center;min-height:100vh;padding:16px}
.login-box{background:var(--panel);border:1px solid var(--line);border-radius:8px;padding:24px;width:min(360px,100%);display:flex;flex-direction:column;gap:8px}
.login-box form{display:flex;flex-direction:column;gap:6px}