:root {
  --bg: #0e1116;
  --panel: #161b22;
  --panel-2: #1c232c;
  --ink: #e6edf3;
  --ink-dim: #8b949e;
  --accent: #f78166;
  --accent-2: #58a6ff;
  --highlight: #ffd166;
  --root: #ef476f;
  --string: #c9d1d9;
  --ok: #3fb950;
  --warn: #d29922;
  --bad: #f85149;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

header {
  padding: clamp(12px, 4vw, 24px) clamp(12px, 4vw, 32px) 8px;
  text-align: center;
}
h1 { margin: 0; font-size: clamp(18px, 5vw, 22px); letter-spacing: 0.5px; }
.sub { margin: 4px 0 0; color: var(--ink-dim); font-size: clamp(11px, 3vw, 13px); }

main {
  padding: 12px clamp(8px, 3vw, 32px) 48px;
  display: flex;
  flex-direction: column;
  gap: clamp(12px, 3vw, 20px);
  max-width: 1100px;
  margin: 0 auto;
}

/* ---------- Fingerboard (vertical strings) ---------- */

#fingerboard {
  background: var(--panel);
  border: 1px solid #232a33;
  border-radius: 12px;
  padding: clamp(14px, 3vw, 24px) clamp(8px, 2vw, 16px) 20px;
  overflow: hidden;
}

.fb-wrap {
  display: flex;
  justify-content: space-between;
  align-items: stretch;
  gap: clamp(8px, 3vw, 56px);
  padding: 8px 0;
  width: 100%;
  max-width: 640px;
  margin: 0 auto;
}

.string-col {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  flex: 1 1 0;
  min-width: 0;
  max-width: 100px;
}

.string-name {
  font-weight: 700;
  font-size: clamp(12px, 3.5vw, 14px);
  color: var(--ink-dim);
  letter-spacing: 1.5px;
  margin-bottom: 12px;
}

.string-track {
  position: relative;
  width: 100%;
  height: clamp(380px, 60vh, 520px);
}

/* the visible string line */
.string-track::before {
  content: "";
  position: absolute;
  top: 0; bottom: 0;
  left: 50%;
  width: 2px;
  background: var(--string);
  opacity: 0.55;
  transform: translateX(-50%);
}
.string-col[data-string="G"] .string-track::before { width: 4px; opacity: 0.75; }
.string-col[data-string="D"] .string-track::before { width: 3px; opacity: 0.7; }
.string-col[data-string="A"] .string-track::before { width: 2.5px; opacity: 0.65; }
.string-col[data-string="E"] .string-track::before { width: 2px; opacity: 0.6; }

/* finger position dot */
.pos {
  position: absolute;
  left: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 2;
}

.dot {
  width: clamp(30px, 9vw, 38px);
  height: clamp(30px, 9vw, 38px);
  border-radius: 50%;
  background: var(--panel-2);
  border: 1px solid #2c343f;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: clamp(11px, 3vw, 13px);
  font-weight: 600;
  color: var(--ink);
  transition: background .12s ease, border-color .12s ease, box-shadow .12s ease;
}
.pos.open .dot {
  background: transparent;
  border-style: dashed;
  color: var(--ink-dim);
}

.pos.in-scale .dot {
  background: var(--highlight);
  color: #1a1300;
  border-color: var(--highlight);
  box-shadow: 0 0 0 4px rgba(255,209,102,0.15);
}
.pos.is-root .dot {
  background: var(--root);
  color: white;
  border-color: var(--root);
  box-shadow: 0 0 0 4px rgba(239,71,111,0.2);
}
.pos.is-target .dot {
  outline: 2px solid var(--accent-2);
  outline-offset: 3px;
}
.pos.hit .dot {
  background: var(--ok) !important;
  color: #002200 !important;
  border-color: var(--ok) !important;
  box-shadow: 0 0 0 6px rgba(63,185,80,0.25), 0 0 16px rgba(63,185,80,0.6) !important;
}

/* finger label to the side */
.finger-tag {
  position: absolute;
  left: calc(50% + clamp(20px, 5vw, 26px));
  top: 50%;
  transform: translateY(-50%);
  font-size: clamp(9px, 2.5vw, 10px);
  color: var(--ink-dim);
  letter-spacing: 0.4px;
  white-space: nowrap;
  pointer-events: none;
}
@media (max-width: 480px) {
  /* Hide labels on narrowest screens — dots already show note */
  .finger-tag { display: none; }
}

/* needle: horizontal bar across string at current pitch */
.needle {
  position: absolute;
  left: -8%;
  right: -8%;
  height: 4px;
  background: var(--bad);
  border-radius: 2px;
  top: 0;
  transform: translateY(-50%);
  z-index: 3;
  opacity: 0;
  transition: top .06s linear, background .12s ease, box-shadow .12s ease;
  pointer-events: none;
}
.needle.show { opacity: 0.95; }
.needle.ok   { background: var(--ok);   box-shadow: 0 0 12px rgba(63,185,80,0.7); }
.needle.warn { background: var(--warn); }
.needle.bad  { background: var(--bad); }

/* ---------- Controls ---------- */

.controls {
  background: var(--panel);
  border: 1px solid #232a33;
  border-radius: 12px;
  padding: 16px 20px;
}
.controls h2 {
  font-size: 13px;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--ink-dim);
  margin: 0 0 12px;
}

.keys { display: flex; gap: 8px; flex-wrap: wrap; justify-content: center; }
.key, #micBtn {
  background: var(--panel-2);
  color: var(--ink);
  border: 1px solid #2c343f;
  padding: 8px 14px;
  border-radius: 8px;
  font-size: 13px;
  cursor: pointer;
  transition: background .12s ease, border-color .12s ease;
}
.key:hover, #micBtn:hover { background: #232c37; }
.key.active { background: var(--accent); border-color: var(--accent); color: #1a0a05; font-weight: 600; }
.key.clear { color: var(--ink-dim); }

.tuner { display: flex; flex-direction: column; gap: 8px; align-items: center; }
.readout { display: flex; gap: 24px; flex-wrap: wrap; font-size: 14px; justify-content: center; }
.readout .freq { color: var(--ink-dim); font-size: 12px; margin-left: 6px; }
#playedNote, #targetNote { font-weight: 600; color: var(--ink); }
.hint { font-size: 12px; color: var(--ink-dim); margin: 0; text-align: center; }