:root {
  --bg: #0b0b10;
  --panel: #15151f;
  --panel-2: #1e1e2d;
  --accent: #22d3ee;
  --accent-2: #3b82f6;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --border: #2a2a3c;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.45;
}

#app {
  max-width: 960px;
  margin: 0 auto;
  padding: 1.25rem;
}

header {
  text-align: center;
  padding: 1rem 0 1.5rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
}

.logo {
  font-size: 2rem;
}

h1 {
  margin: 0;
  font-size: 1.75rem;
  letter-spacing: -0.02em;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.subtitle {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 0.25rem;
}

main {
  display: grid;
  gap: 1rem;
}

section {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1rem;
}

.player-card canvas {
  width: 100%;
  height: 160px;
  background: radial-gradient(circle at 50% 120%, #1e293b, #0f172a);
  border-radius: 10px;
  display: block;
}

.track-info {
  text-align: center;
  margin: 1rem 0 0.75rem;
}

#title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--accent);
}

#artist {
  color: var(--muted);
  font-size: 0.95rem;
}

.progress-row {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 1rem;
}

.progress-row span {
  font-size: 0.8rem;
  color: var(--muted);
  min-width: 2.6rem;
  text-align: center;
}

input[type='range'] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 6px;
  background: var(--panel-2);
  border-radius: 3px;
  outline: none;
}

input[type='range']::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: 2px solid var(--bg);
}

input[type='range']::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  border: 2px solid var(--bg);
}

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

.controls button {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  border: none;
  background: var(--panel-2);
  color: var(--text);
  font-size: 1.35rem;
  cursor: pointer;
  transition: transform 0.1s, background 0.2s;
}

.controls button:hover {
  background: var(--accent-2);
  transform: scale(1.05);
}

.controls button:active {
  transform: scale(0.95);
}

.volume-wrap {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex: 1 1 160px;
  max-width: 220px;
}

.file-area {
  display: flex;
  gap: 0.75rem;
  justify-content: center;
  flex-wrap: wrap;
}

.file-button,
button.secondary {
  padding: 0.6rem 1rem;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.2s, border-color 0.2s;
}

.file-button:hover,
button.secondary:hover {
  background: var(--accent-2);
  border-color: var(--accent-2);
}

.file-button {
  display: inline-block;
}

input[type='file'] {
  display: none;
}

.playlist-card h2,
.eq-card h2,
.surround-card h2,
.tone-card h2,
.extra-card h2 {
  margin: 0 0 0.75rem;
  font-size: 1.05rem;
}

#playlist {
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 220px;
  overflow-y: auto;
}

#playlist li {
  padding: 0.55rem 0.75rem;
  border-radius: 8px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.15s;
}

#playlist li:hover {
  background: var(--panel-2);
}

#playlist li.active {
  background: rgba(34, 211, 238, 0.12);
  border: 1px solid rgba(34, 211, 238, 0.35);
  color: var(--accent);
}

.eq-header,
.surround-header,
.tone-header,
.extra-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 0.75rem;
}

.eq-sliders {
  display: grid;
  grid-template-columns: repeat(10, 1fr);
  gap: 0.35rem;
  align-items: end;
}

.eq-band {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
}

.eq-band label {
  font-size: 0.7rem;
  color: var(--muted);
}

.eq-band input[type='range'] {
  writing-mode: bt-lr;
  -webkit-appearance: slider-vertical;
  width: 22px;
  height: 130px;
  background: transparent;
}

.eq-band input[type='range']::-webkit-slider-thumb {
  width: 14px;
  height: 14px;
}

.eq-band input[type='range']::-moz-range-thumb {
  width: 14px;
  height: 14px;
}

.eq-value {
  font-size: 0.7rem;
  color: var(--accent);
  min-width: 2.2rem;
  text-align: center;
}

.surround-card label,
.tone-card label,
.extra-card label {
  display: block;
  color: var(--muted);
  font-size: 0.9rem;
  margin-bottom: 0.5rem;
}

.toggle {
  position: relative;
  display: inline-block;
  width: 48px;
  height: 26px;
}

.toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.toggle-slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: var(--panel-2);
  border-radius: 26px;
  transition: 0.2s;
  border: 1px solid var(--border);
}

.toggle-slider::before {
  position: absolute;
  content: '';
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background: var(--muted);
  border-radius: 50%;
  transition: 0.2s;
}

.toggle input:checked + .toggle-slider {
  background: rgba(34, 211, 238, 0.15);
  border-color: var(--accent);
}

.toggle input:checked + .toggle-slider::before {
  transform: translateX(22px);
  background: var(--accent);
}

.tone-grid,
.extra-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.extra-grid {
  grid-template-columns: repeat(2, 1fr);
}

.knob-row {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.knob-row label {
  margin-bottom: 0;
}

.knob-value {
  font-size: 0.8rem;
  color: var(--accent);
}

footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.8rem;
  padding: 1rem 0 0;
}

@media (max-width: 700px) {
  .eq-sliders {
    grid-template-columns: repeat(5, 1fr);
  }
  .tone-grid,
  .extra-grid {
    grid-template-columns: 1fr;
  }
  .controls button {
    width: 42px;
    height: 42px;
    font-size: 1.1rem;
  }
}