:root {
  --bg: #fbfbfa;
  --panel: #ffffff;
  --panel-2: #f4f4f2;
  --line: #e4e3df;
  --line-strong: #d3d2cc;
  --ink: #1c1c1a;
  --ink-dim: #6b6b64;
  --ink-faint: #9d9c95;
  --accent: #06B6D4;
  --accent-soft: #ecfeff;
  --red: #dc2626;
  --radius: 12px;
  --disp: 'Space Grotesk', sans-serif;
  --body: 'IBM Plex Sans', sans-serif;
  --mono: 'IBM Plex Mono', monospace;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
body { background: var(--bg); color: var(--ink); font-family: var(--body); }
::selection { background: var(--accent-soft); color: var(--accent); }

.osc-wrap { max-width: 960px; margin: 0 auto; }

.card {
  background: var(--panel); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 18px 20px;
  margin-bottom: 14px; box-shadow: 0 1px 4px rgba(0,0,0,.04);
}

/* ── Source card ──────────────────────────────────────── */
.source-card { padding: 16px 18px; }
.source-row {
  display: flex; align-items: stretch; border: 1px solid var(--line);
  border-radius: 10px; overflow: hidden; margin-bottom: 10px;
}
.src-zone, .src-btn {
  flex: 1; padding: 18px 16px; text-align: center; cursor: pointer;
  background: var(--panel); transition: background .15s;
  display: flex; flex-direction: column; align-items: center; gap: 5px;
  border: none; font-family: inherit;
}
.src-zone:hover, .src-btn:hover { background: var(--accent-soft); }
.src-zone.drag-over { background: var(--accent-soft); outline: 2px dashed var(--accent); }
.src-btn.active { background: var(--accent-soft); }
.src-btn.active .src-icon { color: var(--accent); }
.src-icon  { font-size: 22px; line-height: 1; }
.src-label { font-family: var(--disp); font-size: 13px; font-weight: 700; color: var(--ink); }
.src-sub   { font-family: var(--mono); font-size: 10px; color: var(--ink-faint); max-width: 150px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.src-sep {
  width: 40px; flex-shrink: 0; background: var(--panel-2);
  border-left: 1px solid var(--line); border-right: 1px solid var(--line);
  display: flex; align-items: center; justify-content: center;
  font-family: var(--mono); font-size: 10px; font-weight: 700; color: var(--ink-faint);
}
.source-status { font-family: var(--mono); font-size: 11px; color: var(--ink-dim); text-align: center; }
@media (max-width: 500px) {
  .source-row { flex-direction: column; }
  .src-sep { width: 100%; height: 28px; border-left: none; border-right: none; border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
}

/* ── Controls card ────────────────────────────────────── */
.ctrl-card { padding: 14px 16px; }
.ctrl-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(170px, 1fr));
  gap: 12px 18px;
}
.ctrl-item  { display: flex; flex-direction: column; gap: 6px; }
.ctrl-lbl   { font-family: var(--mono); font-size: 9.5px; letter-spacing: 1px; text-transform: uppercase; color: var(--ink-faint); display: flex; justify-content: space-between; align-items: baseline; }
.ctrl-val   { font-size: 11.5px; font-weight: 700; color: var(--accent); letter-spacing: 0; text-transform: none; }
.ctrl-sel   { font-family: var(--mono); font-size: 12px; padding: 6px 9px; border: 1px solid var(--line-strong); border-radius: 6px; background: var(--panel-2); color: var(--ink); cursor: pointer; outline: none; }
.ctrl-sel:focus { border-color: var(--accent); }
.ctrl-range { -webkit-appearance: none; appearance: none; width: 100%; height: 4px; background: var(--line-strong); border-radius: 2px; outline: none; cursor: pointer; }
.ctrl-range::-webkit-slider-thumb { -webkit-appearance: none; width: 13px; height: 13px; border-radius: 50%; background: #fff; border: 2px solid var(--accent); cursor: pointer; }
.ctrl-range::-moz-range-thumb { width: 13px; height: 13px; border-radius: 50%; background: #fff; border: 2px solid var(--accent); cursor: pointer; }
.toggle-grp { display: flex; border: 1px solid var(--line-strong); border-radius: 6px; overflow: hidden; }
.tog-btn { flex: 1; padding: 6px 0; border: none; background: var(--panel-2); color: var(--ink-dim); font-family: var(--mono); font-size: 10.5px; font-weight: 700; cursor: pointer; transition: all .1s; }
.tog-btn.active { background: var(--accent); color: #fff; }
.tog-btn:hover:not(.active) { background: var(--line); }

/* ── Oscilloscope card ────────────────────────────────── */
.osc-card { padding: 14px 16px; }

.osc-toolbar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 10px; flex-wrap: wrap; gap: 8px; }
.osc-info { font-family: var(--mono); font-size: 11px; color: var(--ink-dim); }
.osc-actions { display: flex; gap: 7px; }
.act-btn { font-family: var(--mono); font-size: 11px; font-weight: 700; padding: 6px 12px; border-radius: 6px; border: 1px solid var(--line-strong); background: var(--panel-2); color: var(--ink-dim); cursor: pointer; transition: all .1s; }
.act-btn:hover:not(:disabled) { border-color: var(--accent); color: var(--accent); }
.act-btn:disabled { opacity: .35; cursor: not-allowed; }
.act-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }
.act-btn.armed  { background: #ff6b00; border-color: #ff6b00; color: #fff; }

/* Display row */
.display-row { display: flex; gap: 0; }

.y-labels {
  width: 52px; flex-shrink: 0; display: flex; flex-direction: column;
  justify-content: space-between; padding: 4px 4px 4px 0;
  font-family: var(--mono); font-size: 9.5px; color: var(--ink-faint);
  text-align: right;
}
.y-label { line-height: 1; }

.osc-canvas-wrap {
  flex: 1; position: relative;
  border-radius: 6px; overflow: hidden;
  border: 1px solid var(--line);
  background: #020c02;
}
#oscCanvas { display: block; width: 100%; cursor: ns-resize; }

/* Trigger level drag handle */
.trig-handle {
  position: absolute; left: 0; right: 0; height: 2px;
  background: rgba(255,200,0,0.6);
  cursor: ns-resize; pointer-events: auto;
}
.trig-handle::before {
  content: '◄';
  position: absolute; left: -1px; top: -8px;
  font-size: 10px; color: rgba(255,200,0,0.9); line-height: 1;
}

/* X-axis labels */
.x-labels-row { display: flex; margin-top: 4px; }
.x-labels-spacer { width: 52px; flex-shrink: 0; }
.x-labels { flex: 1; display: flex; justify-content: space-between; font-family: var(--mono); font-size: 9px; color: var(--ink-faint); padding: 0 4px; }

/* Measurements bar */
.meas-bar { display: flex; gap: 8px; flex-wrap: wrap; margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--line); }
.meas-item { flex: 1; min-width: 100px; background: var(--panel-2); border: 1px solid var(--line); border-radius: 7px; padding: 8px 10px; display: flex; flex-direction: column; gap: 3px; }
.meas-lbl  { font-family: var(--mono); font-size: 9.5px; letter-spacing: 1px; text-transform: uppercase; color: var(--ink-faint); }
.meas-val  { font-family: var(--mono); font-size: 14px; font-weight: 700; color: var(--accent); }