:root {
  --bg: #0f1418;
  --panel: #161d24;
  --panel-2: #1c242c;
  --border: #2a343d;
  --text: #dbe4ea;
  --muted: #8ea0ad;
  --accent: #5fb3d9;
  --accent-2: #9bd15f;
  --warn: #e0a742;
  --bad: #e0616a;
  --good: #6fcf7a;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  font-size: 14px;
}

header {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 0.9rem 1.5rem;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  position: sticky;
  top: 0;
  z-index: 10;
}

header h1 {
  font-size: 1.15rem;
  margin: 0;
  letter-spacing: 0.02em;
}

header .tagline {
  color: var(--muted);
  font-size: 0.82rem;
}

.tabset-nav {
  display: flex;
  gap: 0.25rem;
  flex-wrap: wrap;
}

.tabset-nav button {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 0.45rem 0.9rem;
  border-radius: 6px;
  cursor: pointer;
  font-size: 0.85rem;
  font-family: var(--sans);
}

.tabset-nav button.active {
  color: var(--text);
  border-color: var(--accent);
  background: rgba(95, 179, 217, 0.08);
}

/* Two independent, simultaneously-visible tab sets: data-entry calculators
   on top, the system-model schematic (Coil Network, and more tabs as the
   receive chain grows) below -- always stacked vertically so the user
   enters data up top and watches the model update live underneath. */
.tabset { margin-bottom: 1.75rem; }
.tabset-label {
  font-size: 0.7rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 0.5rem;
}
.tabset-model .tabset-nav { margin-bottom: 0; }
.tabset-data .tabset-nav,
.tabset-model .tabset-nav { margin-bottom: 1rem; }

.wsbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 2.2rem;
  padding: 0.65rem 1.5rem;
  background: var(--panel-2);
  border-bottom: 1px solid var(--border);
  align-items: flex-end;
}
.wsbar-group { display: flex; flex-direction: column; gap: 0.3rem; }
.wsbar-title { font-size: 0.7rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.03em; }
.wsbar-row { display: flex; align-items: center; gap: 0.35rem; flex-wrap: wrap; }
.wsbar-row select,
.wsbar-row input[type=number] {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.3rem 0.4rem;
  border-radius: 5px;
  font-family: var(--mono);
  font-size: 0.82rem;
}
.wsbar-row .unit { color: var(--accent); font-family: var(--mono); font-size: 0.76rem; }
.wsbar-eq { color: var(--muted); font-size: 0.76rem; margin: 0 0.15rem; }
.field-preset {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 0.25rem 0.5rem;
  border-radius: 5px;
  font-size: 0.74rem;
  cursor: pointer;
  font-family: var(--sans);
}
.field-preset:hover { color: var(--text); border-color: var(--accent); }

main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1.5rem;
}

section.view { display: none; }
section.view.active { display: block; }

.grid {
  display: grid;
  grid-template-columns: minmax(280px, 380px) 1fr;
  gap: 1.25rem;
  align-items: start;
}

@media (max-width: 860px) {
  .grid { grid-template-columns: 1fr; }
}

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 1.1rem 1.25rem;
}

.card + .card { margin-top: 1rem; }

h2 { font-size: 1rem; margin: 0 0 0.9rem; color: var(--text); }
h3 { font-size: 0.85rem; margin: 0 0 0.5rem; color: var(--muted); text-transform: uppercase; letter-spacing: 0.04em; }

label {
  display: block;
  font-size: 0.78rem;
  color: var(--muted);
  margin: 0.6rem 0 0.2rem;
}

label .unit { color: var(--accent); font-family: var(--mono); }

input[type=number], select {
  width: 100%;
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 0.4rem 0.55rem;
  border-radius: 6px;
  font-family: var(--mono);
  font-size: 0.88rem;
}

input[type=checkbox] { margin-right: 0.4rem; }

.row { display: flex; gap: 0.6rem; }
.row > div { flex: 1; }

.fieldset {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 0.6rem 0.8rem 0.8rem;
  margin-top: 0.9rem;
}
.fieldset legend {
  font-size: 0.75rem;
  color: var(--accent);
  padding: 0 0.35rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

button.run {
  margin-top: 1rem;
  width: 100%;
  background: var(--accent);
  color: #06232f;
  border: none;
  padding: 0.6rem;
  border-radius: 7px;
  font-weight: 600;
  cursor: pointer;
  font-size: 0.92rem;
}
button.run:hover { filter: brightness(1.08); }
button.run:disabled { opacity: 0.6; cursor: default; }

.result-empty {
  color: var(--muted);
  font-style: italic;
  padding: 2rem 0;
  text-align: center;
}

.kv {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.25rem 0.8rem;
  font-family: var(--mono);
  font-size: 0.9rem;
}
.kv .k { color: var(--muted); }
.kv .v { text-align: right; }

.stat-big {
  font-size: 1.9rem;
  font-family: var(--mono);
  color: var(--accent-2);
  margin: 0.1rem 0 0.3rem;
}
.stat-sub { color: var(--muted); font-size: 0.8rem; }

.note {
  font-size: 0.8rem;
  color: var(--muted);
  border-left: 2px solid var(--border);
  padding-left: 0.6rem;
  margin: 0.5rem 0;
  line-height: 1.4;
}

.warn-banner {
  background: rgba(224, 167, 66, 0.12);
  border: 1px solid var(--warn);
  color: var(--warn);
  border-radius: 6px;
  padding: 0.5rem 0.7rem;
  font-size: 0.82rem;
  margin-bottom: 0.7rem;
}

.pill {
  display: inline-block;
  padding: 0.1rem 0.55rem;
  border-radius: 100px;
  font-size: 0.72rem;
  font-family: var(--mono);
  border: 1px solid var(--border);
}
.pill.good { color: var(--good); border-color: var(--good); }
.pill.bad { color: var(--bad); border-color: var(--bad); }

.side-by-side {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.8rem;
  margin: 0.6rem 0;
}
.side-by-side .box {
  background: var(--panel-2);
  border-radius: 8px;
  padding: 0.7rem 0.9rem;
  border: 1px solid var(--border);
}
.side-by-side .box .label { color: var(--muted); font-size: 0.76rem; text-transform: uppercase; }
.side-by-side .box .value { font-family: var(--mono); font-size: 1.3rem; margin-top: 0.2rem; }

table { border-collapse: collapse; width: 100%; font-family: var(--mono); font-size: 0.85rem; }
table th, table td { padding: 0.3rem 0.5rem; border-bottom: 1px solid var(--border); text-align: right; }
table th:first-child, table td:first-child { text-align: left; }

.hist {
  display: flex;
  align-items: flex-end;
  gap: 1px;
  height: 90px;
  margin: 0.6rem 0;
  background: var(--panel-2);
  border-radius: 6px;
  padding: 4px;
}
.hist .bar {
  flex: 1;
  background: var(--accent);
  min-height: 1px;
  border-radius: 1px 1px 0 0;
}
.hist .bar.in-band { background: var(--good); }

.matrix-input {
  display: grid;
  gap: 0.4rem;
}
.matrix-input .cell-row { display: flex; gap: 0.4rem; }
.complex-pair { display: flex; gap: 0.2rem; align-items: center; }
.complex-pair input { width: 4.4rem; }
.complex-pair span { color: var(--muted); font-family: var(--mono); font-size: 0.8rem; }

footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.76rem;
  padding: 2rem 0 1.5rem;
}

.error-banner {
  background: rgba(224, 97, 106, 0.12);
  border: 1px solid var(--bad);
  color: var(--bad);
  border-radius: 6px;
  padding: 0.6rem 0.8rem;
  font-size: 0.85rem;
  margin-bottom: 0.8rem;
}

.carry-slot:empty { margin: 0; }
.carry-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  background: rgba(155, 209, 95, 0.1);
  border: 1px solid var(--accent-2);
  color: var(--accent-2);
  border-radius: 100px;
  padding: 0.15rem 0.5rem 0.15rem 0.6rem;
  font-size: 0.72rem;
  font-family: var(--mono);
  margin: 0.3rem 0 0.2rem;
}
.carry-badge em { font-style: normal; color: var(--muted); }
.carry-badge .carry-clear {
  background: none;
  border: none;
  color: var(--accent-2);
  cursor: pointer;
  font-size: 0.95rem;
  line-height: 1;
  padding: 0 0.15rem;
  font-family: var(--sans);
}
.carry-badge .carry-clear:hover { color: var(--bad); }

.carry-hint-note {
  font-size: 0.72rem;
  color: var(--muted);
  font-style: italic;
  margin: 0.3rem 0 0.2rem;
}

/* -- Coil Network tab ---------------------------------------------------- */

#coil-svg {
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 8px;
}
.loop-wire { stroke: var(--text); stroke-width: 3; stroke-linecap: round; }
.cap-plate { stroke: var(--accent); stroke-width: 3; stroke-linecap: round; }
.junction-hit {
  fill: var(--panel-2);
  stroke: var(--border);
  stroke-width: 1.5;
  cursor: pointer;
}
.junction-hit:hover { stroke: var(--accent); }
.junction-hit.is-match { fill: rgba(155, 209, 95, 0.22); stroke: var(--accent-2); stroke-width: 2; }
.junction-label { fill: var(--muted); font-size: 10px; font-family: var(--mono); }
.match-lead { stroke: var(--accent-2); stroke-width: 2; }
.match-port { fill: var(--panel); stroke: var(--accent-2); stroke-width: 2; }
.match-text { fill: var(--accent-2); font-size: 8.5px; font-family: var(--mono); }
.block-wire { stroke: var(--warn); stroke-width: 1.6; }
.diode-tri { fill: var(--warn); stroke: var(--warn); }
.diode-bar { stroke: var(--warn); stroke-width: 2.4; }
.inductor-path { stroke: var(--warn); stroke-width: 1.8; }
.block-label { fill: var(--warn); font-size: 8.5px; font-family: var(--mono); }

.junction-row {
  display: flex;
  align-items: center;
  gap: 0.8rem;
  padding: 0.4rem 0.3rem;
  border-bottom: 1px solid var(--border);
  font-size: 0.82rem;
}
.junction-row.is-match { background: rgba(155, 209, 95, 0.06); }
.junction-row label {
  display: flex;
  align-items: center;
  gap: 0.3rem;
  margin: 0;
  color: var(--text);
  font-size: 0.82rem;
}
.junction-row-label { white-space: nowrap; }
.junction-row input[type=radio],
.junction-row input[type=checkbox] { width: auto; margin: 0; }
.junction-lblock { color: var(--warn); font-family: var(--mono); font-size: 0.76rem; margin-left: auto; }

.preamp-tri { fill: var(--accent); stroke: var(--accent); }
.preamp-label { fill: var(--accent); font-size: 8px; font-family: var(--mono); }
.matchnet-box { fill: rgba(95, 179, 217, 0.08); stroke: var(--accent); stroke-width: 1.3; }
.matchnet-label { fill: var(--accent); font-size: 7.5px; font-family: var(--mono); }
.coax-outer { fill: none; stroke: var(--muted); stroke-width: 2; }
.coax-inner { fill: var(--muted); }

.z0-preset {
  background: none;
  border: 1px solid var(--border);
  color: var(--muted);
  padding: 0.25rem 0.5rem;
  border-radius: 5px;
  font-size: 0.74rem;
  cursor: pointer;
  font-family: var(--sans);
}
.z0-preset:hover { color: var(--text); border-color: var(--accent); }

.landing h2 { font-size: 1.4rem; }
.landing ul { line-height: 1.9; }
.landing .ephemeral {
  border: 1px solid var(--accent-2);
  color: var(--accent-2);
  border-radius: 8px;
  padding: 0.8rem 1rem;
  font-size: 0.85rem;
  margin-top: 1rem;
}