@import url('https://fonts.googleapis.com/css2?family=Silkscreen:wght@400;700&family=JetBrains+Mono:wght@400;500;600;700&family=Inter:wght@400;500;600;700&display=swap');

:root {
  /* White FR4 solder mask, like the real AIOR boards, with dark silkscreen ink. */
  --pcb: #f7f5ec;
  --pcb-hi: #fffefa;
  --pcb-dark: #ece7d8;
  --pcb-darker: #ddd6c2;
  --silk: #1b2219;
  --silk-dim: #5c665b;
  --copper: #a4712f;
  --copper-bright: #c68f42;
  --pad-gold: #c1943f;
  --trace: #1f8a54;
  --warn: #e2a13c;
  --warn-ink: #7a4a12;
  --danger: #b8402a;
  --line: rgba(27, 34, 25, 0.14);
  --line-strong: rgba(27, 34, 25, 0.26);
  --font-display: 'Silkscreen', 'JetBrains Mono', monospace;
  --font-body: 'Inter', system-ui, -apple-system, 'Segoe UI', sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  background: var(--pcb-darker);
}

body {
  font-family: var(--font-body);
  color: var(--silk);
  background:
    radial-gradient(circle at 50% 0%, rgba(31, 138, 84, 0.07), transparent 60%),
    var(--pcb-darker);
  background-image:
    radial-gradient(circle, rgba(27, 34, 25, 0.07) 1px, transparent 1.4px),
    radial-gradient(circle at 50% 0%, rgba(31, 138, 84, 0.07), transparent 60%);
  background-size: 28px 28px, 100% 100%;
  padding: clamp(1rem, 3vw, 2.5rem);
}

/* This is a physical-hardware likeness (a real white AIOR board), not a themed
   document — it intentionally keeps its one finish rather than following the
   OS light/dark preference. */
@media (prefers-color-scheme: dark) {
  body { background-color: var(--pcb-darker); }
}

.sr-only {
  position: absolute; width: 1px; height: 1px;
  padding: 0; margin: -1px; overflow: hidden;
  clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* ---------- Board shell ---------- */

.board {
  max-width: 1180px;
  margin: 0 auto;
}

.board__header { margin-bottom: 1.75rem; }

.board__brand {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.chip {
  flex: none;
  width: 46px;
  height: 46px;
  border-radius: 4px;
  background: linear-gradient(155deg, #2a2f28, #14170f);
  border: 1px solid var(--line-strong);
  position: relative;
  box-shadow: 0 2px 5px rgba(27,34,25,0.25), inset 0 0 0 3px rgba(238,241,230,0.06);
}
.chip::before {
  content: "";
  position: absolute; inset: 10px;
  border: 1px solid var(--copper);
  border-radius: 2px;
}
.chip::after {
  content: "";
  position: absolute; inset: 0;
  background-image:
    repeating-linear-gradient(to right, var(--copper) 0 3px, transparent 3px 9px);
  background-position: center top, center bottom;
  background-repeat: no-repeat;
  background-size: 100% 4px;
  background-position-y: -1px, calc(100% + 1px);
}

h1 {
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.6vw, 1.9rem);
  letter-spacing: 0.06em;
  margin: 0 0 0.3rem;
  color: var(--silk);
}

.board__tagline {
  margin: 0;
  color: var(--silk-dim);
  font-size: 0.92rem;
  max-width: 46ch;
}

.trace-rule {
  margin-top: 1.25rem;
  height: 10px;
  position: relative;
}
.trace-rule span {
  position: absolute; left: 0; right: 0; top: 4px;
  height: 2px;
  background: linear-gradient(to right, var(--copper) 0%, var(--trace) 50%, var(--copper) 100%);
  opacity: 0.85;
}
.trace-rule::before, .trace-rule::after {
  content: "";
  position: absolute; top: 1px; width: 8px; height: 8px; border-radius: 50%;
  background: var(--pad-gold);
  box-shadow: 0 0 5px rgba(193,148,63,0.5);
}
.trace-rule::before { left: -2px; }
.trace-rule::after { right: -2px; }

/* ---------- Layout ---------- */

.layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
  gap: 1.25rem;
  align-items: start;
}

@media (max-width: 880px) {
  .layout { grid-template-columns: 1fr; }
}

.panel {
  background:
    radial-gradient(circle, rgba(27,34,25,0.05) 1px, transparent 1.3px) 0 0/22px 22px,
    linear-gradient(165deg, var(--pcb-hi), var(--pcb));
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 1.4rem 1.4rem 1.6rem;
  box-shadow: 0 18px 32px -22px rgba(27,34,25,0.35), inset 0 1px 0 rgba(255,255,255,0.7);
}

.panel__title {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-size: 0.95rem;
  letter-spacing: 0.04em;
  color: var(--silk);
  margin: 1.5rem 0 0.5rem;
}
.panel__title:first-of-type { margin-top: 0.25rem; }

.pad-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: radial-gradient(circle at 35% 30%, var(--copper-bright), var(--copper) 70%);
  color: #2a1607;
  font-family: var(--font-mono);
  font-weight: 700;
  font-size: 0.75rem;
  box-shadow: inset 0 0 0 1px rgba(0,0,0,0.25);
}

.panel__hint {
  margin: 0 0 0.9rem;
  color: var(--silk-dim);
  font-size: 0.85rem;
  line-height: 1.5;
  max-width: 58ch;
}

/* ---------- Reference (AIOR pinout) ---------- */

.reference {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.6rem 0.8rem 0.8rem;
  margin-bottom: 1.4rem;
  background: rgba(27, 34, 25, 0.035);
}
.reference summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-weight: 600;
  font-size: 0.8rem;
  letter-spacing: 0.03em;
  color: var(--copper);
  padding: 0.3rem 0.1rem;
  list-style: none;
}
.reference summary::-webkit-details-marker { display: none; }
.reference summary::before { content: "▸ "; }
.reference[open] summary::before { content: "▾ "; }
.reference__hint { color: var(--silk-dim); font-weight: 400; }

.reference__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(148px, 1fr));
  gap: 0.4rem;
  margin-top: 0.6rem;
}
.ref-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.35rem 0.5rem;
  border-radius: 5px;
  background: rgba(255,255,255,0.65);
  border: 1px solid var(--line);
}
.ref-item .pad-badge { width: 18px; height: 18px; font-size: 0.65rem; flex: none; }
.ref-item .swatch { flex: none; }
.ref-item .ref-item__text { color: var(--silk-dim); line-height: 1.25; }
.ref-item .ref-item__text b { color: var(--silk); font-weight: 600; display: block; }

/* ---------- Pin grid (form) ---------- */

.pin-grid {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.pin-row {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  padding: 0.55rem 0.6rem 0.6rem;
  border-radius: 7px;
  background: rgba(27, 34, 25, 0.035);
  border: 1px solid var(--line);
}

.pin-row__head {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.pin-row__swatch { width: 14px; flex: none; }

input[type="text"] {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--silk);
  background: #fffefb;
  border: 1px solid var(--line-strong);
  border-radius: 5px;
  padding: 0.45rem 0.55rem;
  outline: none;
  width: 100%;
  min-width: 0;
}

input[type="text"]:focus-visible, .toggle:focus-visible {
  outline: 2px solid var(--copper-bright);
  outline-offset: 2px;
}

.pin-row input[type="text"] {
  color: var(--silk-dim);
  flex: 1;
}

/* Function chips - a radio pin can carry more than one signal (e.g. a
   combined PTT+TX-data pin), so these are independent toggles, not a
   single-choice control. */
.pin-row__chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  padding-left: calc(22px + 14px + 1.2rem);
  margin-top: 0.15rem;
}

.fn-chip {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  color: var(--silk-dim);
  background: #fdfbf5;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  padding: 0.22rem 0.65rem;
  white-space: nowrap;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, box-shadow 0.15s ease;
}
.fn-chip:hover { border-color: var(--trace); }
.fn-chip:focus-visible {
  outline: none;
  box-shadow: 0 0 0 2px var(--pcb), 0 0 0 4px var(--copper-bright);
}
.fn-chip[aria-pressed="true"] {
  background: linear-gradient(160deg, rgba(31,138,84,0.2), rgba(31,138,84,0.08));
  border-color: var(--trace);
  color: var(--trace);
  font-weight: 600;
}

@media (max-width: 560px) {
  .pin-row__chips { padding-left: 0; }
}

/* ---------- Toggles ---------- */

.toggle-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
  margin-bottom: 0.4rem;
}

.toggle {
  font-family: var(--font-body);
  text-align: left;
  cursor: pointer;
  border-radius: 8px;
  border: 1px solid var(--line-strong);
  background: #fdfbf5;
  color: var(--silk-dim);
  padding: 0.65rem 0.8rem;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
  transition: background 0.15s ease, border-color 0.15s ease, color 0.15s ease, transform 0.1s ease;
}
.toggle:hover { border-color: var(--trace); }
.toggle:active { transform: translateY(1px); }

.toggle__label {
  font-weight: 700;
  font-size: 0.88rem;
  color: inherit;
}
.toggle__desc {
  font-size: 0.74rem;
  line-height: 1.4;
  color: var(--silk-dim);
}

.toggle[aria-pressed="true"] {
  background: linear-gradient(160deg, rgba(31,138,84,0.16), rgba(31,138,84,0.05));
  border-color: var(--trace);
  color: var(--silk);
}
.toggle[aria-pressed="true"] .toggle__label { color: var(--trace); }
.toggle[aria-pressed="true"] .toggle__desc { color: var(--silk); }

@media (max-width: 560px) {
  .toggle-row, .toggle-row--wide { grid-template-columns: 1fr; }
}

/* ---------- Diagram ---------- */
/* A recessed sub-panel in the same white finish as the rest of the board;
   wires carry their own dark ink outline so they stay legible on it. */

.diagram-card {
  background:
    radial-gradient(circle, rgba(27,34,25,0.05) 1px, transparent 1.3px) 0 0/22px 22px,
    var(--pcb-dark);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.75rem 0.75rem 0.5rem;
}

.diagram { width: 100%; overflow-x: auto; }
.diagram svg { display: block; width: 100%; height: auto; }

.diagram__legend {
  margin: 0.4rem 0.2rem 0.1rem;
  font-family: var(--font-mono);
  font-size: 0.68rem;
  color: var(--silk-dim);
  line-height: 1.6;
}

/* ---------- Notes / warnings ---------- */

.notes {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin: 1rem 0;
}

.note {
  font-size: 0.82rem;
  line-height: 1.5;
  border-radius: 7px;
  padding: 0.6rem 0.75rem;
  border: 1px solid var(--line);
  background: rgba(27, 34, 25, 0.03);
  color: var(--silk-dim);
}
.note--warn {
  border-color: rgba(226, 161, 60, 0.5);
  background: rgba(226, 161, 60, 0.12);
  color: var(--warn-ink);
}
.note--warn::before { content: "⚠ "; color: var(--warn-ink); }
.note--info::before { content: "ℹ "; color: var(--trace); }

/* ---------- Table ---------- */

.table-wrap { overflow-x: auto; }

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.82rem;
  font-family: var(--font-mono);
}

thead th {
  text-align: left;
  font-family: var(--font-body);
  font-weight: 600;
  color: var(--copper);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  padding: 0.5rem 0.6rem;
  border-bottom: 1px solid var(--line-strong);
  white-space: nowrap;
}

tbody td {
  padding: 0.55rem 0.6rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  color: var(--silk);
}

tbody tr:last-child td { border-bottom: none; }
tbody tr:hover { background: rgba(27, 34, 25, 0.035); }

.cell-pin {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  white-space: nowrap;
}

.cell-signal b { color: var(--silk); }
.cell-signal span { display: block; color: var(--silk-dim); font-size: 0.72rem; font-family: var(--font-body); }

.cell-dash { color: var(--silk-dim); }

.cell-note {
  color: var(--silk-dim);
  font-family: var(--font-body);
  font-size: 0.72rem;
  font-style: italic;
}

.swatch {
  display: inline-block;
  width: 20px; height: 10px;
  border-radius: 2px;
  flex: none;
  box-shadow: inset 0 0 0 1px rgba(0,0,0,0.25);
}

.badge-flag {
  display: inline-block;
  margin-left: 0.4rem;
  font-family: var(--font-body);
  font-size: 0.65rem;
  font-weight: 700;
  color: #2a1607;
  background: var(--warn);
  border-radius: 3px;
  padding: 0.05rem 0.32rem;
  vertical-align: middle;
}

/* ---------- Footer ---------- */

.board__footer {
  margin-top: 1.75rem;
  padding-top: 1rem;
  border-top: 1px solid var(--line);
  color: var(--silk-dim);
  font-size: 0.76rem;
  max-width: 80ch;
}

@media (prefers-reduced-motion: reduce) {
  * { transition: none !important; }
}