/* ============================================================
   BASS-SYNTH.CSS — LakeShoreDr Bass Synth Styles
   Resistor Technology · resistor.technology

   Two themes: "bunker" (site default) and "vintage" (classic 303).
   All custom properties prefixed --bs-* to avoid conflicts.
   All classes BEM-prefixed bs__ to avoid conflicts.
   ============================================================ */

/* --- Theme: Bunker (default — dark teal/brass) --- */
.bass-synth,
.bass-synth[data-theme="bunker"] {
  --bs-bg:              #0e0e12;
  --bs-surface:         #14141a;
  --bs-surface-raised:  #1e1e24;
  --bs-border:          #2a2a30;
  --bs-border-light:    #3a3a40;
  --bs-text:            #d8d5cd;
  --bs-text-secondary:  #9a9a9e;
  --bs-text-muted:      #6a6a70;
  --bs-accent:          #5ab8a0;
  --bs-accent-light:    #70d0b8;
  --bs-accent-dark:     #408878;

  /* Step group colors (4 groups of 4) */
  --bs-step-g1:         #5ab8a0;   /* teal */
  --bs-step-g2:         #a080c0;   /* amethyst */
  --bs-step-g3:         #c4a67a;   /* brass */
  --bs-step-g4:         #9a9a9e;   /* silver */

  /* VU meter */
  --bs-vu-bg:           linear-gradient(to bottom, #1a2a28, #0e1a18);
  --bs-vu-border:       #2a5a4a;
  --bs-vu-text:         rgba(90, 184, 160, 0.5);
  --bs-vu-needle:       rgba(90, 184, 160, 0.9);
  --bs-vu-needle-tip:   rgba(90, 184, 160, 0.3);
  --bs-vu-scale:        rgba(90, 184, 160, 0.25);
  --bs-vu-hub:          #408878;

  /* LED */
  --bs-led-on:          #5ab8a0;
  --bs-led-off:         #1a1a20;
  --bs-led-glow:        rgba(90, 184, 160, 0.6);

  /* Fonts */
  --bs-font-display:    'Space Grotesk', sans-serif;
  --bs-font-mono:       'IBM Plex Mono', monospace;
}

/* --- Theme: Vintage (classic silver-face 303) --- */
.bass-synth[data-theme="vintage"] {
  --bs-bg:              #e8e0c8;
  --bs-surface:         #d8d0b8;
  --bs-surface-raised:  #c8c0a8;
  --bs-border:          #b0a890;
  --bs-border-light:    #c8c0a8;
  --bs-text:            #2a2018;
  --bs-text-secondary:  #504030;
  --bs-text-muted:      #8a7a68;
  --bs-accent:          #c04020;
  --bs-accent-light:    #e05030;
  --bs-accent-dark:     #903018;

  /* Classic 303 step colors */
  --bs-step-g1:         #c04020;   /* red */
  --bs-step-g2:         #d07020;   /* orange */
  --bs-step-g3:         #c0a020;   /* gold */
  --bs-step-g4:         #504030;   /* brown */

  /* VU meter — cream face */
  --bs-vu-bg:           linear-gradient(to bottom, #f5f0e0, #e8e0c8);
  --bs-vu-border:       #a09070;
  --bs-vu-text:         rgba(40, 30, 20, 0.6);
  --bs-vu-needle:       rgba(20, 15, 10, 0.9);
  --bs-vu-needle-tip:   rgba(20, 15, 10, 0.3);
  --bs-vu-scale:        rgba(40, 30, 20, 0.25);
  --bs-vu-hub:          #504030;

  /* LED */
  --bs-led-on:          #c04020;
  --bs-led-off:         #c8b8a0;
  --bs-led-glow:        rgba(192, 64, 32, 0.6);

  /* Fonts — fallback stack */
  --bs-font-display:    Helvetica, Arial, sans-serif;
  --bs-font-mono:       'Courier New', Courier, monospace;
}

/* ============================================================
   CONTAINER
   ============================================================ */

.bass-synth {
  background: var(--bs-bg);
  border: 1px solid var(--bs-border);
  border-radius: 12px;
  padding: 1.5rem;
  max-width: 720px;
  margin: 0 auto;
  font-family: var(--bs-font-mono);
  color: var(--bs-text);
  user-select: none;
  -webkit-user-select: none;
  box-shadow:
    0 4px 24px rgba(0, 0, 0, 0.4),
    inset 0 1px 0 rgba(255, 255, 255, 0.04);
}

/* ============================================================
   HEADER ROW
   ============================================================ */

.bs__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  gap: 0.75rem;
  flex-wrap: wrap;
}

.bs__title {
  font-family: var(--bs-font-display);
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--bs-accent);
}

/* --- Acid Smiley (303 culture nod) --- */

.bs__smiley {
  display: inline-block;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--bs-accent);
  position: relative;
  flex-shrink: 0;
  box-shadow: 0 0 8px rgba(90, 184, 160, 0.3);
  transition: box-shadow 300ms, transform 300ms;
}

.bs__smiley:hover {
  box-shadow: 0 0 14px rgba(90, 184, 160, 0.5);
  transform: scale(1.1);
}

.bs__smiley-eye {
  position: absolute;
  width: 4px;
  height: 5px;
  border-radius: 50%;
  background: var(--bs-bg);
  top: 7px;
}

.bs__smiley-eye--l { left: 6px; }
.bs__smiley-eye--r { right: 6px; }

.bs__smiley-mouth {
  position: absolute;
  bottom: 5px;
  left: 50%;
  transform: translateX(-50%);
  width: 12px;
  height: 6px;
  border-bottom: 2.5px solid var(--bs-bg);
  border-radius: 0 0 6px 6px;
}

.bass-synth[data-theme="bunker"] .bs__smiley {
  box-shadow: 0 0 8px rgba(90, 184, 160, 0.3);
}

.bass-synth[data-theme="vintage"] .bs__smiley {
  box-shadow: 0 0 8px rgba(192, 64, 32, 0.3);
}

.bs__transport {
  display: flex;
  gap: 0.5rem;
}

.bs__btn {
  padding: 0.4rem 1rem;
  border: 1px solid var(--bs-border-light);
  border-radius: 4px;
  background: var(--bs-surface);
  color: var(--bs-text-secondary);
  font-family: var(--bs-font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  cursor: pointer;
  transition: background 150ms, border-color 150ms, color 150ms;
}

.bs__btn:hover {
  background: var(--bs-surface-raised);
  border-color: var(--bs-accent);
  color: var(--bs-text);
}

.bs__btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 2px;
}

.bs__btn.is-active {
  background: var(--bs-accent);
  border-color: var(--bs-accent);
  color: var(--bs-bg);
}

.bs__theme-toggle {
  padding: 0.4rem 0.75rem;
  border: 1px solid var(--bs-border);
  border-radius: 4px;
  background: transparent;
  color: var(--bs-text-muted);
  font-family: var(--bs-font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  cursor: pointer;
  transition: color 150ms, border-color 150ms;
}

.bs__theme-toggle:hover {
  color: var(--bs-text);
  border-color: var(--bs-border-light);
}

.bs__theme-toggle:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 2px;
}

/* ============================================================
   LED STRIP — 16 position indicators
   ============================================================ */

.bs__leds {
  display: flex;
  gap: 4px;
  justify-content: center;
  margin-bottom: 1rem;
  padding: 0.5rem 0;
}

.bs__led {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--bs-led-off);
  transition: background 80ms, box-shadow 80ms;
  flex-shrink: 0;
}

.bs__led.is-active {
  background: var(--bs-led-on);
  box-shadow: 0 0 6px var(--bs-led-glow), 0 0 12px var(--bs-led-glow);
}

/* ============================================================
   CONTROLS ROW — Knobs, BPM, VU Meter
   ============================================================ */

.bs__controls {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.bs__knob-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.25rem;
}

/* --- Rotary Knob (matches site knob style) --- */

.bs__knob-wrap {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
  cursor: grab;
  touch-action: none;
  user-select: none;
  outline: none;
}

.bs__knob-wrap:active {
  cursor: grabbing;
}

.bs__knob-wrap.is-active {
  cursor: grabbing;
}

.bs__knob-label {
  font-family: var(--bs-font-mono);
  font-size: 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.25em;
  color: var(--bs-text-muted);
  text-align: center;
}

.bs__knob {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  position: relative;
  background: conic-gradient(from 200deg, #1a1a1a, #3a3a3a 90deg, #2a2a2a 180deg, #3a3a3a 270deg, #1a1a1a);
  box-shadow:
    0 3px 8px rgba(0, 0, 0, 0.6),
    inset 0 -2px 4px rgba(0, 0, 0, 0.4),
    inset 0 2px 3px rgba(255, 255, 255, 0.06),
    0 0 0 2px #111;
  transition: box-shadow 150ms;
}

.bs__knob:hover {
  box-shadow:
    0 3px 8px rgba(0, 0, 0, 0.6),
    inset 0 -2px 4px rgba(0, 0, 0, 0.4),
    inset 0 2px 3px rgba(255, 255, 255, 0.06),
    0 0 0 2px #111,
    0 0 12px rgba(90, 184, 160, 0.2);
}

.bs__knob-wrap:focus-visible .bs__knob {
  box-shadow:
    0 3px 8px rgba(0, 0, 0, 0.6),
    inset 0 -2px 4px rgba(0, 0, 0, 0.4),
    inset 0 2px 3px rgba(255, 255, 255, 0.06),
    0 0 0 3px var(--bs-accent);
}

/* Knob hub */
.bs__knob-cap {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 12px;
  height: 12px;
  background: radial-gradient(circle, #444, #222);
  border-radius: 50%;
  box-shadow: inset 0 1px 2px rgba(0, 0, 0, 0.5);
}

/* Knob pointer */
.bs__knob::after {
  content: '';
  position: absolute;
  top: 4px;
  left: 50%;
  transform: translateX(-50%);
  width: 2px;
  height: 10px;
  background: #e8e0d0;
  border-radius: 1px;
}

.bs__knob--small {
  /* Smaller knob variant */
}

.bs__knob--small .bs__knob {
  width: 36px;
  height: 36px;
}

.bs__knob--small .bs__knob::after {
  top: 3px;
  height: 8px;
}

.bs__knob--small .bs__knob-cap {
  width: 10px;
  height: 10px;
}

/* --- BPM Display --- */

.bs__bpm-display {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.bs__bpm-value {
  font-family: var(--bs-font-mono);
  font-size: 1.1rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--bs-accent);
  min-width: 3ch;
  text-align: center;
  background: rgba(0, 0, 0, 0.3);
  padding: 0.25rem 0.5rem;
  border: 1px solid var(--bs-border);
  border-radius: 3px;
}

.bs__bpm-label {
  font-size: 0.55rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--bs-text-muted);
}

.bs__bpm-btn {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--bs-border);
  border-radius: 3px;
  background: var(--bs-surface);
  color: var(--bs-text-secondary);
  font-size: 0.85rem;
  cursor: pointer;
  transition: background 150ms, color 150ms;
  line-height: 1;
}

.bs__bpm-btn:hover {
  background: var(--bs-surface-raised);
  color: var(--bs-text);
}

.bs__bpm-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 1px;
}

/* --- VU Meter Container --- */

.bs__vu-container {
  flex-shrink: 0;
}

.bs__vu-meter {
  width: 100px;
  height: 56px;
  background: var(--bs-vu-bg);
  border: 1px solid var(--bs-vu-border);
  border-radius: 4px;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
  box-shadow:
    0 2px 6px rgba(0, 0, 0, 0.5),
    inset 0 0 20px rgba(90, 184, 160, 0.08);
}

.bs__vu-face {
  position: absolute;
  top: 4px;
  left: 50%;
  transform: translateX(-50%);
  font-family: var(--bs-font-mono);
  font-size: 6px;
  color: var(--bs-vu-text);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.bs__vu-scale {
  position: absolute;
  bottom: 12px;
  left: 10px;
  right: 10px;
  height: 26px;
  border-top: 1px solid var(--bs-vu-scale);
  border-radius: 50% 50% 0 0 / 100% 100% 0 0;
}

.bs__vu-marks {
  position: absolute;
  bottom: 10px;
  left: 8px;
  right: 8px;
  display: flex;
  justify-content: space-between;
  font-family: var(--bs-font-mono);
  font-size: 5px;
  color: var(--bs-vu-text);
}

.bs__vu-needle {
  position: absolute;
  bottom: 8px;
  left: 50%;
  width: 1px;
  height: 34px;
  background: linear-gradient(to top, var(--bs-vu-needle), var(--bs-vu-needle-tip));
  transform-origin: bottom center;
  transform: rotate(-30deg);
  box-shadow: 0 0 3px rgba(90, 184, 160, 0.3);
}

.bs__vu-needle::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 50%;
  transform: translateX(-50%);
  width: 4px;
  height: 4px;
  background: var(--bs-vu-hub);
  border-radius: 50%;
}

/* ============================================================
   WAVEFORM TOGGLE — SAW / SQR
   ============================================================ */

.bs__wave-toggle {
  display: flex;
  gap: 0.5rem;
  justify-content: center;
  margin-bottom: 1rem;
}

.bs__wave-btn {
  padding: 0.35rem 1.2rem;
  border: 1px solid var(--bs-border);
  border-radius: 4px;
  background: var(--bs-surface);
  color: var(--bs-text-muted);
  font-family: var(--bs-font-mono);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  cursor: pointer;
  transition: background 150ms, border-color 150ms, color 150ms;
  min-width: 60px;
  text-align: center;
}

.bs__wave-btn:hover {
  background: var(--bs-surface-raised);
  color: var(--bs-text-secondary);
}

.bs__wave-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 2px;
}

.bs__wave-btn.is-active {
  background: var(--bs-accent-dark);
  border-color: var(--bs-accent);
  color: var(--bs-text);
}

/* ============================================================
   NOTE DISPLAY — shows note name for selected step
   ============================================================ */

.bs__note-display {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.bs__note-value {
  font-family: var(--bs-font-mono);
  font-size: 1.3rem;
  font-weight: 600;
  letter-spacing: 0.1em;
  color: var(--bs-accent);
  min-width: 4ch;
  text-align: center;
  background: rgba(0, 0, 0, 0.3);
  padding: 0.3rem 0.75rem;
  border: 1px solid var(--bs-border);
  border-radius: 3px;
}

.bs__note-btn {
  width: 28px;
  height: 28px;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--bs-border);
  border-radius: 3px;
  background: var(--bs-surface);
  color: var(--bs-text-secondary);
  font-family: var(--bs-font-mono);
  font-size: 1rem;
  cursor: pointer;
  transition: background 150ms, color 150ms, border-color 150ms;
  line-height: 1;
}

.bs__note-btn:hover {
  background: var(--bs-surface-raised);
  color: var(--bs-text);
  border-color: var(--bs-border-light);
}

.bs__note-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 1px;
}

.bs__note-label {
  font-size: 0.55rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--bs-text-muted);
}

/* ============================================================
   STEP GRID — 16 steps in 4 groups of 4
   ============================================================ */

.bs__step-grid {
  display: flex;
  gap: 3px;
  justify-content: center;
  padding: 0.75rem 0;
}

/* Visual gap between groups of 4 */
.bs__step-group {
  display: flex;
  gap: 3px;
}

.bs__step-group + .bs__step-group {
  margin-left: 6px;
}

.bs__step-btn {
  width: 36px;
  height: 36px;
  border: 1px solid var(--bs-border);
  border-radius: 3px;
  background: var(--bs-surface);
  cursor: pointer;
  transition: background 100ms, border-color 100ms, box-shadow 100ms;
  position: relative;
}

.bs__step-btn:hover {
  border-color: var(--bs-border-light);
}

.bs__step-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 1px;
}

/* Active step (has a note programmed) — group colors */
.bs__step-group:nth-child(1) .bs__step-btn.is-on {
  background: var(--bs-step-g1);
  border-color: var(--bs-step-g1);
}

.bs__step-group:nth-child(2) .bs__step-btn.is-on {
  background: var(--bs-step-g2);
  border-color: var(--bs-step-g2);
}

.bs__step-group:nth-child(3) .bs__step-btn.is-on {
  background: var(--bs-step-g3);
  border-color: var(--bs-step-g3);
}

.bs__step-group:nth-child(4) .bs__step-btn.is-on {
  background: var(--bs-step-g4);
  border-color: var(--bs-step-g4);
}

/* Glow per group (bunker theme) */
.bass-synth[data-theme="bunker"] .bs__step-group:nth-child(1) .bs__step-btn.is-on,
.bass-synth:not([data-theme]) .bs__step-group:nth-child(1) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(90, 184, 160, 0.4);
}
.bass-synth[data-theme="bunker"] .bs__step-group:nth-child(2) .bs__step-btn.is-on,
.bass-synth:not([data-theme]) .bs__step-group:nth-child(2) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(160, 128, 192, 0.4);
}
.bass-synth[data-theme="bunker"] .bs__step-group:nth-child(3) .bs__step-btn.is-on,
.bass-synth:not([data-theme]) .bs__step-group:nth-child(3) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(196, 166, 122, 0.4);
}
.bass-synth[data-theme="bunker"] .bs__step-group:nth-child(4) .bs__step-btn.is-on,
.bass-synth:not([data-theme]) .bs__step-group:nth-child(4) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(154, 154, 158, 0.4);
}

/* Glow per group (vintage theme) */
.bass-synth[data-theme="vintage"] .bs__step-group:nth-child(1) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(192, 64, 32, 0.4);
}
.bass-synth[data-theme="vintage"] .bs__step-group:nth-child(2) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(208, 112, 32, 0.4);
}
.bass-synth[data-theme="vintage"] .bs__step-group:nth-child(3) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(192, 160, 32, 0.4);
}
.bass-synth[data-theme="vintage"] .bs__step-group:nth-child(4) .bs__step-btn.is-on {
  box-shadow: 0 0 8px rgba(80, 64, 48, 0.4);
}

/* Current playback step highlight */
.bs__step-btn.is-current {
  box-shadow: inset 0 0 0 2px var(--bs-accent);
}

/* Selected step for editing */
.bs__step-btn.is-selected {
  outline: 2px solid var(--bs-accent-light);
  outline-offset: 1px;
}

/* ============================================================
   ACCENT ROW — 16 small accent toggles
   ============================================================ */

.bs__accent-row {
  display: flex;
  gap: 3px;
  justify-content: center;
  padding: 0.25rem 0;
  margin-bottom: 0.25rem;
}

.bs__accent-group {
  display: flex;
  gap: 3px;
}

.bs__accent-group + .bs__accent-group {
  margin-left: 6px;
}

.bs__accent-btn {
  width: 36px;
  height: 20px;
  border: 1px solid var(--bs-border);
  border-radius: 2px;
  background: var(--bs-surface);
  cursor: pointer;
  transition: background 100ms, border-color 100ms, box-shadow 100ms;
  position: relative;
  font-family: var(--bs-font-mono);
  font-size: 0;
  color: transparent;
}

.bs__accent-btn:hover {
  border-color: var(--bs-border-light);
}

.bs__accent-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 1px;
}

.bs__accent-btn.is-on {
  background: var(--bs-accent);
  border-color: var(--bs-accent);
  box-shadow: 0 0 6px rgba(90, 184, 160, 0.3);
}

.bass-synth[data-theme="vintage"] .bs__accent-btn.is-on {
  box-shadow: 0 0 6px rgba(192, 64, 32, 0.3);
}

/* Accent indicator dot */
.bs__accent-btn::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--bs-text-muted);
  opacity: 0.3;
  transition: opacity 100ms, background 100ms;
}

.bs__accent-btn.is-on::after {
  background: var(--bs-bg);
  opacity: 0.8;
}

/* Row label */
.bs__accent-row-label,
.bs__slide-row-label {
  font-family: var(--bs-font-mono);
  font-size: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--bs-text-muted);
  writing-mode: vertical-lr;
  text-orientation: mixed;
  display: flex;
  align-items: center;
  margin-right: 0.25rem;
}

/* ============================================================
   SLIDE ROW — 16 small slide toggles
   ============================================================ */

.bs__slide-row {
  display: flex;
  gap: 3px;
  justify-content: center;
  padding: 0.25rem 0;
  margin-bottom: 0.5rem;
}

.bs__slide-group {
  display: flex;
  gap: 3px;
}

.bs__slide-group + .bs__slide-group {
  margin-left: 6px;
}

.bs__slide-btn {
  width: 36px;
  height: 16px;
  border: 1px solid var(--bs-border);
  border-radius: 2px;
  background: var(--bs-surface);
  cursor: pointer;
  transition: background 100ms, border-color 100ms, box-shadow 100ms;
  position: relative;
  font-size: 0;
  color: transparent;
}

.bs__slide-btn:hover {
  border-color: var(--bs-border-light);
}

.bs__slide-btn:focus-visible {
  outline: 2px solid var(--bs-accent);
  outline-offset: 1px;
}

.bs__slide-btn.is-on {
  background: var(--bs-accent-dark);
  border-color: var(--bs-accent);
  box-shadow: 0 0 4px rgba(90, 184, 160, 0.2);
}

.bass-synth[data-theme="vintage"] .bs__slide-btn.is-on {
  box-shadow: 0 0 4px rgba(192, 64, 32, 0.2);
}

/* Slide indicator line */
.bs__slide-btn::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 25%;
  right: 25%;
  height: 1px;
  background: var(--bs-text-muted);
  opacity: 0.3;
  transition: opacity 100ms, background 100ms, transform 100ms;
  transform: translateY(-50%);
}

.bs__slide-btn.is-on::after {
  background: var(--bs-accent-light);
  opacity: 0.9;
  transform: translateY(-50%) scaleY(2);
}

/* ============================================================
   SECTION LABELS
   ============================================================ */

.bs__section-label {
  font-family: var(--bs-font-mono);
  font-size: 0.55rem;
  text-transform: uppercase;
  letter-spacing: 0.25em;
  color: var(--bs-text-muted);
  text-align: center;
  margin-bottom: 0.25rem;
}

/* ============================================================
   RESPONSIVE
   ============================================================ */

@media (max-width: 600px) {
  .bass-synth {
    padding: 1rem;
    border-radius: 8px;
  }

  .bs__header {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
  }

  .bs__controls {
    gap: 0.75rem;
  }

  .bs__knob {
    width: 36px;
    height: 36px;
  }

  .bs__knob::after {
    top: 3px;
    height: 8px;
  }

  .bs__knob-cap {
    width: 10px;
    height: 10px;
  }

  .bs__step-btn {
    width: 28px;
    height: 28px;
  }

  .bs__accent-btn {
    width: 28px;
    height: 16px;
  }

  .bs__slide-btn {
    width: 28px;
    height: 13px;
  }

  .bs__vu-meter {
    width: 80px;
    height: 48px;
  }

  .bs__vu-needle {
    height: 28px;
  }

  .bs__note-value {
    font-size: 1.1rem;
    padding: 0.2rem 0.5rem;
  }

  .bs__note-btn {
    width: 24px;
    height: 24px;
    font-size: 0.85rem;
  }

  .bs__wave-btn {
    padding: 0.3rem 0.8rem;
    font-size: 0.6rem;
    min-width: 50px;
  }
}

@media (max-width: 400px) {
  .bs__step-btn {
    width: 22px;
    height: 22px;
  }

  .bs__accent-btn {
    width: 22px;
    height: 14px;
  }

  .bs__slide-btn {
    width: 22px;
    height: 11px;
  }

  .bs__step-group + .bs__step-group,
  .bs__accent-group + .bs__accent-group,
  .bs__slide-group + .bs__slide-group {
    margin-left: 3px;
  }

  .bs__vu-container {
    display: none;
  }

  .bs__bpm-value {
    font-size: 0.9rem;
  }

  .bs__controls {
    gap: 0.5rem;
  }

  .bs__note-display {
    gap: 0.3rem;
  }

  .bs__note-value {
    font-size: 0.95rem;
    min-width: 3ch;
  }
}

/* ============================================================
   REDUCED MOTION
   ============================================================ */

@media (prefers-reduced-motion: reduce) {
  .bs__led,
  .bs__step-btn,
  .bs__accent-btn,
  .bs__slide-btn,
  .bs__wave-btn,
  .bs__btn,
  .bs__note-btn,
  .bs__vu-needle,
  .bs__knob {
    transition: none !important;
  }

  .bs__vu-needle {
    display: none;
  }
}