:root {
  --bg: #f4f6f9;
  --card: #ffffff;
  --ink: #22313f;
  --muted: #6b7a8c;
  --line: #dde3ea;
  --indigo: #5c6bc0;
  --indigo-dark: #3949ab;
  --teal: #26a69a;
  --orange: #ef6c00;
  --green: #2e7d32;
  --red: #c62828;
  --radius: 10px;
  font-size: 15px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--ink);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, -apple-system, "Segoe UI", sans-serif;
}

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

h1, h2, h3 { margin: 0; font-weight: 700; }

button, select, input {
  font: inherit;
  color: inherit;
}

button {
  cursor: pointer;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 8px;
  padding: 8px 14px;
  transition: background .15s, border-color .15s;
}
button:hover { background: #f2f4f8; border-color: #c8d0da; }
button:disabled { opacity: .5; cursor: not-allowed; }

button.primary { background: var(--indigo); border-color: var(--indigo); color: #fff; }
button.primary:hover { background: var(--indigo-dark); }
button.ghost { background: transparent; }
button.small { padding: 4px 10px; font-size: 13px; }
button.orange { background: #fff3e0; border-color: #ffb74d; color: #e65100; font-weight: 600; }
button.orange.active { background: var(--orange); border-color: #e65100; color: #fff; }
button.range { background: #e8eaf6; border-color: #9fa8da; color: #283593; font-weight: 600; }
button.range.active { background: var(--green); border-color: #1b5e20; color: #fff; }
button.danger { background: #ffebee; border-color: #ef9a9a; color: var(--red); }
button.block { width: 100%; }

/* torque is on: red, because the motor is energized */
button.torque-on {
  background: #ffebee;
  border-color: #ef9a9a;
  color: var(--red);
  font-weight: 700;
}
button.torque-on:hover { background: #ffcdd2; border-color: #e57373; }

input, select {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px 10px;
  background: #fff;
  min-width: 0;
}

/* address / length are filled by clicking a row in the register table */
input[readonly] {
  background: #f3f5f8;
  color: #546e7a;
  cursor: default;
}

/* ---------------- top bar ---------------- */
.topbar {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
  align-items: center;
  justify-content: space-between;
  padding: 14px 20px;
  background: var(--card);
  border-bottom: 1px solid var(--line);
}

.brand { display: flex; align-items: baseline; gap: 10px; flex-wrap: wrap; }
.brand h1 { font-size: 20px; color: #1a237e; }
.brand .sub { font-size: 12px; color: var(--muted); }

.ports { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

.port-chip {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: #fbfcfe;
  font-size: 13px;
}
.port-chip .chip-name { font-weight: 600; }
.chip-status {
  font-size: 12px;
  color: var(--muted);
  padding: 2px 8px;
  border-radius: 999px;
  background: #eef1f5;
}
.chip-status.on { background: #e0f2f1; color: #00695c; }

.mock-toggle {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--muted);
  user-select: none;
}

.link-baud {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--muted);
}
.link-baud select { padding: 5px 8px; }

/* ---------------- tabs / panels ---------------- */
.tabs {
  display: flex;
  gap: 8px;
  padding: 12px 20px 0;
}
.tab {
  border: 1px solid transparent;
  border-bottom: 2px solid transparent;
  border-radius: 8px 8px 0 0;
  background: transparent;
  padding: 9px 16px;
  color: var(--muted);
}
.tab:hover { background: #e9edf3; }
.tab.active {
  color: var(--indigo-dark);
  background: var(--card);
  border-color: var(--line);
  border-bottom-color: var(--indigo);
  font-weight: 600;
}

main { flex: 1 1 auto; padding: 0 20px 16px; }
.panel { display: none; }
.panel.active { display: block; }

.arms {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(430px, 1fr));
  gap: 16px;
  margin-top: 14px;
}

.arm-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 14px;
  min-width: 0;
}
.arm-card > header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 10px;
}
.arm-card h2 { font-size: 16px; }
.arm-card .conn { font-size: 12px; color: var(--muted); }
.arm-card .conn.on { color: var(--teal); }

.quick { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 12px; }

/* ---------------- tables ---------------- */
.servo-table, .param-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}
.servo-table th, .servo-table td,
.param-table th, .param-table td {
  border-bottom: 1px solid #eef1f5;
  padding: 7px 8px;
  text-align: left;
  white-space: nowrap;
}
.servo-table th, .param-table th {
  color: var(--muted);
  font-weight: 600;
  font-size: 12px;
  border-bottom: 1px solid var(--line);
}
.servo-table td.num { font-variant-numeric: tabular-nums; }
.servo-table tr.offline td { color: #a0aab5; }
.servo-table td button { padding: 4px 8px; font-size: 12px; }

.param-wrap {
  max-height: 420px;
  overflow: auto;
  border: 1px solid var(--line);
  border-radius: 8px;
}
.param-table tbody tr { cursor: pointer; }
.param-table tbody tr:hover { background: #f3f6fb; }
.param-table tbody tr.selected { background: #e8eaf6; }
.param-table tbody tr.locked { color: #90a4ae; cursor: default; }
.param-table tbody tr.locked:hover { background: transparent; }
.param-table td:nth-child(1), .param-table td:nth-child(3) { font-variant-numeric: tabular-nums; }

/* ---------------- single servo ---------------- */
.single-row {
  display: grid;
  grid-template-columns: 42px 96px 1fr 70px auto;
  gap: 8px;
  align-items: center;
  padding: 7px 0;
  border-bottom: 1px solid #eef1f5;
}
.single-row .sid { font-weight: 700; font-size: 13px; }
.single-row input[type="number"] { width: 100%; }
.single-row .lval { font-size: 12px; color: var(--indigo); font-variant-numeric: tabular-nums; }
.single-row .rowbtns { display: flex; gap: 6px; }
.single-row.offline { opacity: .45; pointer-events: none; }

input[type="range"] { width: 100%; accent-color: var(--indigo); }

/* ---------------- FT debugger ---------------- */
.ft-toolbar {
  display: flex;
  gap: 10px;
  align-items: center;
  flex-wrap: wrap;
  margin: 14px 0;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 10px 14px;
}
.ft-toolbar label { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--muted); }

.ft-grid {
  display: grid;
  grid-template-columns: minmax(360px, 1.2fr) minmax(320px, 1fr);
  gap: 16px;
  align-items: start;
}
@media (max-width: 900px) { .ft-grid { grid-template-columns: 1fr; } }

fieldset {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  padding: 12px 14px 14px;
  margin: 0 0 14px;
}
legend { padding: 0 6px; font-size: 13px; color: var(--muted); font-weight: 600; }

.form-row { display: flex; gap: 10px; align-items: center; margin-bottom: 10px; }
.form-row.wrap { flex-wrap: wrap; }
.form-row label { display: flex; align-items: center; gap: 6px; font-size: 13px; color: var(--muted); }
.form-row input[type="number"] { width: 90px; }

/* usage guide tab */
.guide {
  max-width: 900px;
  margin: 14px auto 0;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 28px 28px;
  line-height: 1.75;
}
.guide h2 { color: #1a237e; font-size: 20px; }
.guide h3 { margin: 22px 0 8px; color: #37474f; font-size: 15px; }
.guide .lead { color: var(--muted); margin: 8px 0 4px; }
.guide ul, .guide ol { margin: 6px 0 6px 22px; padding: 0; }
.guide li { margin: 5px 0; }
.guide code {
  background: #f1f4f8;
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 12px;
  word-break: break-all;
}
.guide ul.paths { list-style: none; margin-left: 0; }
.guide ul.paths li {
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex-wrap: wrap;
  margin: 6px 0;
}
.guide ul.paths li > span { color: var(--muted); font-size: 13px; min-width: 64px; }
.guide .note {
  background: #fff8e1;
  border-left: 3px solid #ffc107;
  padding: 8px 12px;
  border-radius: 6px;
  color: #8d6e00;
  font-size: 13px;
}

/* ---------------- log ---------------- */
.log-bar {
  background: var(--card);
  border-top: 1px solid var(--line);
  padding: 8px 20px 12px;
}
.log-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 12px;
  color: var(--muted);
  margin-bottom: 6px;
}
.log {
  height: 104px;
  overflow: auto;
  font-family: "Cascadia Mono", Consolas, "Courier New", monospace;
  font-size: 12px;
  line-height: 1.5;
  background: #fbfcfe;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 6px 10px;
  white-space: pre-wrap;
}
.log .ts { color: #9aa7b4; }

/* ---------------- wizard ---------------- */
dialog#wizard {
  width: min(1100px, 96vw);
  max-height: 92vh;
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 0;
  box-shadow: 0 24px 60px rgba(20, 40, 70, .25);
  background: var(--bg);
}
dialog#wizard::backdrop { background: rgba(16, 28, 44, .45); }

.wizard-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  background: var(--card);
  border-bottom: 1px solid var(--line);
}
.wizard-head h2 { font-size: 17px; color: #1a237e; }
.wizard-head .wizard-sub { font-size: 12px; color: var(--muted); flex: 1; }

.wizard-body {
  display: grid;
  grid-template-columns: minmax(380px, 1fr) minmax(420px, 1.15fr);
  gap: 16px;
  padding: 16px 18px 20px;
  overflow: auto;
  max-height: calc(92vh - 60px);
}
@media (max-width: 950px) { .wizard-body { grid-template-columns: 1fr; } }

.wizard-body h3 { font-size: 14px; color: var(--muted); margin-bottom: 8px; }
.monitor, .calib { background: var(--card); border: 1px solid var(--line); border-radius: var(--radius); padding: 14px; }

.monitor-row {
  display: grid;
  grid-template-columns: 40px 92px 1fr;
  gap: 8px;
  align-items: center;
  padding: 6px 0;
  border-bottom: 1px solid #eef1f5;
}
.monitor-row .sid { font-weight: 700; font-size: 13px; }
.monitor-row .pval { font-variant-numeric: tabular-nums; font-size: 13px; }

.wizard-actions { display: flex; gap: 10px; margin: 12px 0; }
.wizard-actions button { flex: 1; padding: 11px 12px; }

.id-row { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; font-size: 13px; color: var(--muted); }
.id-row input { flex: 1; }

.hint { font-size: 12px; color: var(--muted); margin: 8px 0 0; line-height: 1.5; }
.hint.warn { color: var(--orange); }

.save-result {
  margin-top: 12px;
  padding: 12px 14px;
  border: 1px solid #a5d6a7;
  border-radius: 10px;
  background: #f1f8f2;
  font-size: 13px;
  line-height: 1.6;
}
.save-result .save-title { color: #1b5e20; font-weight: 600; margin-bottom: 6px; }
.save-result .save-label { color: var(--muted); font-size: 12px; }
.save-result .save-path {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 4px 0 6px;
}
.save-result .save-path code {
  flex: 1;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 12px;
  word-break: break-all;
}
.save-result .save-note { color: var(--orange); font-size: 12px; }

.banner {
  margin: 10px 20px 0;
  padding: 10px 14px;
  border-radius: 8px;
  background: #fff8e1;
  border: 1px solid #ffe082;
  color: #8d6e00;
  font-size: 13px;
}
.hidden { display: none !important; }

/* small screens */
@media (max-width: 700px) {
  .topbar { padding: 12px; }
  .ports { gap: 8px; }
  .tabs { padding: 10px 12px 0; overflow-x: auto; }
  main { padding: 0 12px 12px; }
  .arms { grid-template-columns: 1fr; }
  .single-row { grid-template-columns: 38px 82px 1fr auto; }
  .single-row .lval { display: none; }
}