/* Knob, fader, crossfader and pad. */

.knob {
  display: grid;
  justify-items: center;
  gap: 8px;
  width: 80px;
  flex: none;
}
.knob--sm {
  width: 62px;
  gap: 6px;
}
.knob__dial {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  cursor: grab;
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
}
.knob--sm .knob__dial {
  width: 46px;
  height: 46px;
}
.knob__dial.is-grabbed {
  cursor: grabbing;
}
.knob__dial svg {
  display: block;
  width: 100%;
  height: 100%;
  overflow: visible;
}
.knob__track,
.knob__arc {
  fill: none;
  stroke-width: 3;
}
.knob__track {
  stroke: var(--hb-line);
  stroke-linecap: round;
}
.knob__arc {
  stroke: var(--hb-ink);
  stroke-dasharray: 0 100;
  transition: stroke 0.15s;
}
.knob__hand {
  transform-origin: 32px 32px;
}
.knob__cap {
  fill: var(--hb-raise);
  stroke: var(--hb-line);
  stroke-width: 1;
  transition: fill 0.15s;
}
.knob__needle {
  stroke: var(--hb-ink);
  stroke-width: 2.5;
  stroke-linecap: round;
}
/* a switch is a knob that clicks between named positions */
.knob--switch .knob__cap {
  stroke: var(--hb-ink-4);
  stroke-dasharray: 2 3;
}
.knob--switch .knob__value {
  color: var(--hb-ink);
}
.knob__dial:hover .knob__cap {
  fill: var(--hb-line);
}
.knob__dial.is-grabbed .knob__arc,
.knob__dial:focus-visible .knob__arc {
  stroke: var(--hb-accent);
}
.knob__dial:focus-visible {
  outline-offset: 3px;
  border-radius: 50%;
}

.knob__text {
  display: grid;
  justify-items: center;
  gap: 4px;
  width: 100%;
  text-align: center;
}
.knob__label,
.knob__sub,
.knob__value {
  max-width: 100%;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.knob__label {
  font: 500 10.5px/1.1 var(--hb-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--hb-ink);
}
.knob--sm .knob__label {
  font-size: 9.5px;
  letter-spacing: 0.04em;
}
.knob__sub {
  font: 400 10px/1.1 var(--hb-mono);
  color: var(--hb-ink-4);
}
.knob__value {
  font: 400 11px/1.1 var(--hb-mono);
  font-variant-numeric: tabular-nums;
  color: var(--hb-ink-2);
}
.knob--sm .knob__value {
  font-size: 10.5px;
}

.fader {
  position: relative;
  display: grid;
  justify-items: center;
  width: 30px;
  height: 88px;
  border-radius: 4px;
  cursor: ns-resize;
  touch-action: none;
  transition: opacity 0.2s;
}
.fader__rail {
  position: relative;
  width: 3px;
  height: 100%;
  border-radius: 2px;
  background: var(--hb-line);
}
/* unity gain mark (100% of 125%) */
.fader__rail::before {
  content: '';
  position: absolute;
  left: -6px;
  bottom: calc(0.8 * (100% - 10px) + 4.5px);
  width: 15px;
  height: 1px;
  background: var(--hb-ink-5);
}
.fader__fill {
  position: absolute;
  inset: auto 0 0;
  height: calc(var(--p, 0) * (100% - 10px) + 5px);
  border-radius: 2px;
  background: var(--hb-ink-3);
}
.fader__cap {
  position: absolute;
  left: 50%;
  bottom: calc(var(--p, 0) * (100% - 10px));
  width: 22px;
  height: 10px;
  transform: translateX(-50%);
  border-radius: 2px;
  background: var(--hb-ink);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.6);
}
.fader__cap::after {
  content: '';
  position: absolute;
  inset: 4.5px 3px auto;
  height: 1px;
  background: var(--hb-bg-deep);
}
.fader.is-grabbed .fader__cap,
.fader:focus-visible .fader__cap {
  background: var(--hb-accent);
}

/* crossfader: the same idea, lying down */
.xfader {
  position: relative;
  display: grid;
  align-items: center;
  width: 100%;
  height: 26px;
  border-radius: 4px;
  cursor: ew-resize;
  touch-action: none;
}
.xfader__rail {
  position: relative;
  height: 3px;
  border-radius: 2px;
  background: var(--hb-line);
}
.xfader__rail::before {
  content: '';
  position: absolute;
  left: 50%;
  top: -6px;
  width: 1px;
  height: 15px;
  background: var(--hb-ink-5);
}
.xfader__cap {
  position: absolute;
  top: 50%;
  left: calc(var(--p, 0) * (100% - 12px));
  width: 12px;
  height: 22px;
  transform: translateY(-50%);
  border-radius: 2px;
  background: var(--hb-ink);
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.6);
}
.xfader__cap::after {
  content: '';
  position: absolute;
  inset: 3px auto 3px 5.5px;
  width: 1px;
  background: var(--hb-bg-deep);
}
.xfader.is-grabbed .xfader__cap,
.xfader:focus-visible .xfader__cap {
  background: var(--hb-accent);
}

/* a pad is on for as long as it is held */
.pad {
  position: relative;
  display: grid;
  place-items: center;
  border: 1px solid var(--hb-line);
  border-radius: 6px;
  background: var(--hb-panel);
  color: var(--hb-ink-2);
  touch-action: none;
  user-select: none;
  -webkit-user-select: none;
  transition: background 0.06s, color 0.06s, border-color 0.06s, transform 0.06s;
}
.pad:hover {
  border-color: var(--hb-ink-4);
  color: var(--hb-ink);
}
.pad[aria-pressed='true'] {
  background: var(--hb-accent);
  border-color: var(--hb-accent);
  color: var(--hb-accent-ink);
  transform: translateY(1px);
}
.pad__label {
  font: 500 10.5px/1.15 var(--hb-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-align: center;
  padding-top: 6px;
}
.pad__key {
  position: absolute;
  top: 4px;
  left: 6px;
  min-width: 0;
  padding: 0;
  border: 0;
  font-size: 9px;
  color: var(--hb-ink-4);
}
.pad[aria-pressed='true'] .pad__key {
  color: var(--hb-accent-ink);
}
@media (hover: none) {
  .pad__key {
    display: none;
  }
}