/* Dark theme shared with Ladder Sim: dark panels, amber accent, Segoe UI. */
:root {
  --bg: #0d1117;
  --panel: #161b22;
  --panel2: #1f2630;
  --line: #30363d;
  --text: #e6edf3;
  --muted: #8b949e;
  --acc: #f5a623;
  --ok: #3fb950;
  --bad: #f85149;
  --blue: #58a6ff;
  --code-bg: #0a0e14;
  color-scheme: dark;
}
* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.6 "Segoe UI", system-ui, -apple-system, Roboto, sans-serif;
}
a { color: var(--blue); }
a:hover { color: var(--acc); }
.wrap { max-width: 880px; margin: 0 auto; padding: 0 16px; }

/* header / footer */
.site-header { background: var(--panel); border-bottom: 2px solid var(--acc); }
.site-header .wrap { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: 8px 24px; padding-top: 10px; padding-bottom: 10px; }
.logo { font-weight: 700; font-size: 1.2rem; color: var(--text); text-decoration: none; }
.logo span { color: var(--acc); }
.site-nav { display: flex; gap: 6px; }
.site-nav a { color: var(--muted); text-decoration: none; padding: 6px 12px; border-radius: 6px; }
.site-nav a:hover { color: var(--text); }
.site-nav a[aria-current="page"] { background: var(--acc); color: #111; font-weight: 600; }
.site-footer { margin-top: 56px; padding: 24px 0 40px; border-top: 1px solid var(--line); color: var(--muted); font-size: 0.9rem; }
.site-footer nav { display: flex; flex-wrap: wrap; gap: 8px 20px; margin-bottom: 12px; }
.site-footer a { color: var(--muted); }
.site-footer a:hover { color: var(--acc); }

/* calculator tabs */
.tabs { display: flex; gap: 4px; flex-wrap: wrap; margin: 0 0 18px; padding-bottom: 8px; border-bottom: 1px solid var(--line); }
.tabs a { color: var(--muted); text-decoration: none; padding: 7px 14px; border-radius: 6px; font-size: 0.95rem; }
.tabs a:hover { color: var(--text); background: var(--panel2); }
.tabs a[aria-current="page"] { background: var(--acc); color: #111; font-weight: 600; }

/* content */
main { padding: 22px 0 0; }
h1 { font-size: 1.8rem; line-height: 1.25; margin: 0 0 8px; }
h2 { font-size: 1.25rem; margin: 32px 0 8px; }
h3 { font-size: 1.05rem; margin: 20px 0 4px; }
.lede { color: var(--muted); font-size: 1.05rem; margin: 0 0 20px; }
li { margin-bottom: 4px; }

/* cards on index pages */
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 14px; margin: 20px 0; padding: 0; list-style: none; }
.card { display: block; height: 100%; background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 14px; text-decoration: none; color: var(--text); }
.card:hover { border-color: var(--acc); }
.card strong { display: block; font-size: 1.05rem; color: var(--acc); margin-bottom: 4px; }
.card span { color: var(--muted); font-size: 0.95rem; }

/* calculator */
.calc { background: var(--panel); border: 1px solid var(--line); border-radius: 10px; padding: 14px; margin: 14px 0; }
.calc h2 { margin-top: 0; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.6px; color: var(--muted); }
.row { display: grid; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); gap: 12px; margin-bottom: 12px; }
label { display: block; font-size: 0.85rem; color: var(--muted); margin-bottom: 4px; }
input, select {
  width: 100%; font: inherit; color: var(--text); background: var(--bg);
  border: 1px solid var(--line); border-radius: 6px; padding: 8px 10px; min-height: 42px;
}
input:focus, select:focus { outline: 0; border-color: var(--acc); }
.hint { font-size: 0.85rem; color: var(--muted); margin: 4px 0 0; }
.results { background: var(--code-bg); border: 1px solid var(--line); border-left: 4px solid var(--ok); border-radius: 6px; padding: 12px 16px; margin-top: 8px; }
.results dl { margin: 0; display: grid; grid-template-columns: auto 1fr; gap: 4px 16px; }
.results dt { color: var(--muted); }
.results dd { margin: 0; font: 700 1rem Consolas, monospace; color: var(--acc); }
.results .empty { color: var(--muted); margin: 0; }
.results p { margin: 8px 0 0; }
.results.warn { border-left-color: var(--bad); }
.note { background: rgba(245, 166, 35, 0.1); border: 1px solid rgba(245, 166, 35, 0.4); border-radius: 6px; padding: 10px 14px; font-size: 0.95rem; margin: 16px 0; }
.formula { background: var(--code-bg); border: 1px solid var(--line); border-left: 4px solid var(--acc); border-radius: 6px; padding: 10px 14px; font-family: Consolas, ui-monospace, monospace; font-size: 0.92rem; color: #d2e3ff; overflow-x: auto; margin: 12px 0; }
table { border-collapse: collapse; width: 100%; margin: 12px 0; font-size: 0.95rem; }
th, td { border: 1px solid var(--line); padding: 6px 10px; text-align: left; }
th { background: var(--panel); }
textarea { width: 100%; min-height: 150px; font: 0.92rem/1.5 Consolas, ui-monospace, monospace; color: var(--text); background: var(--code-bg); border: 1px solid var(--line); border-radius: 6px; padding: 10px; resize: vertical; white-space: pre; overflow: auto; }
textarea:focus { outline: 0; border-color: var(--acc); }
.tablewrap { overflow-x: auto; margin-top: 8px; max-height: 480px; overflow-y: auto; }
.tableout table { font-size: 0.85rem; margin: 0; }
.tableout th { position: sticky; top: 0; background: var(--panel2); }
.tableout td { font-family: Consolas, ui-monospace, monospace; white-space: nowrap; }
.export-msg { color: var(--ok); font-size: 0.9rem; }
.toolbar { display: flex; flex-wrap: wrap; align-items: center; gap: 8px 10px; margin: 0 0 4px; }
button { font: inherit; background: var(--panel2); color: var(--text); border: 1px solid var(--line); border-radius: 6px; padding: 6px 12px; cursor: pointer; }
button:hover { border-color: var(--acc); }
button:focus-visible, summary:focus-visible { outline: 2px solid var(--acc); outline-offset: 2px; }
#toolbar-msg, #contact-msg { color: var(--ok); font-size: 0.9rem; }
a.btn { display: inline-block; font: inherit; background: var(--panel2); color: var(--text); border: 1px solid var(--line); border-radius: 6px; padding: 6px 12px; text-decoration: none; }
a.btn:hover { border-color: var(--acc); color: var(--text); }
.copy-result { margin-top: 8px; font-size: 0.85rem; padding: 4px 10px; color: var(--muted); }
.results .subhead { font-size: 0.85rem; text-transform: uppercase; letter-spacing: 0.5px; color: var(--muted); margin: 14px 0 6px; }
details.steps { margin-top: 10px; border-top: 1px solid var(--line); padding-top: 8px; }
details.steps summary { cursor: pointer; color: var(--blue); font-size: 0.9rem; }
details.steps ol { margin: 8px 0 0; padding-left: 20px; color: var(--text); font-size: 0.92rem; }
.provenance { margin-top: 32px; padding: 14px 16px; background: var(--panel); border: 1px solid var(--line); border-radius: 10px; font-size: 0.9rem; color: var(--muted); }
.provenance h2 { margin: 0 0 6px; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.6px; }
.provenance ul { margin: 0 0 8px; padding-left: 20px; }
.provenance p { margin: 0; }
.install-link { background: none; border: 0; color: var(--blue); padding: 0; text-decoration: underline; }
.print-only { display: none; }
.loopcheck td:empty::before { content: "\00a0"; display: inline-block; min-width: 64px; }
.loopcheck td { height: 30px; }

/* Checklists */
.checklist-head, .sign-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 12px; margin: 0 0 12px; }
.checklist-head label, .sign-row label { font-size: 0.85rem; color: var(--muted); }
.checks { list-style: none; margin: 0 0 8px; padding: 0; }
.checks li { margin: 0; border-bottom: 1px solid var(--line); }
.checks label { display: flex; gap: 12px; align-items: flex-start; padding: 8px 4px; color: var(--text); font-size: 1rem; cursor: pointer; }
.checks input[type="checkbox"] { width: 20px; height: 20px; min-height: 0; margin-top: 3px; flex: none; accent-color: var(--acc); }
.checks input[type="checkbox"]:checked + span { color: var(--muted); text-decoration: line-through; }
.checklist textarea { min-height: 120px; white-space: pre-wrap; }
.symptoms td:first-child { font-weight: 600; white-space: nowrap; }
.callout { background: rgba(248, 81, 73, 0.1); border: 1px solid rgba(248, 81, 73, 0.45); border-radius: 6px; padding: 10px 14px; margin: 16px 0; font-size: 0.95rem; }

@media print {
  .no-print, .site-header, .site-footer, .tabs, .toolbar, .copy-result, .calc.no-print { display: none !important; }
  :root { --bg: #fff; --panel: #fff; --panel2: #f2f2f2; --line: #999; --text: #000; --muted: #333; --code-bg: #fff; --acc: #000; --blue: #000; --ok: #000; }
  body { background: #fff; color: #000; font-size: 11pt; }
  .wrap { max-width: none; padding: 0; }
  h1 { font-size: 18pt; }
  h2 { font-size: 13pt; break-after: avoid; }
  .checks li { break-inside: avoid; }
  .checks input[type="checkbox"] { width: 14px; height: 14px; accent-color: #000; }
  .checks input[type="checkbox"]:checked + span { text-decoration: none; color: #000; }
  input, textarea { border: 0; border-bottom: 1px solid #000; border-radius: 0; background: #fff; color: #000; }
  .tablewrap { max-height: none; overflow: visible; }
  .tableout th { position: static; background: #eee; color: #000; }
  .tableout td, .tableout th { border-color: #000; white-space: normal; }
  .provenance { display: none; }
  .print-only { display: block; }
  .loopcheck td { height: 9mm; }
  a { color: #000; text-decoration: none; }
}
.disclaimer { font-size: 0.85rem; color: var(--muted); margin-top: 28px; }

@media (max-width: 600px) {
  h1 { font-size: 1.5rem; }
  .tabs a { padding: 6px 10px; font-size: 0.9rem; }
}