:root {
  --void: #05070d;
  --panel: #10152a;
  --panel-alt: #141a34;
  --line: rgba(255, 255, 255, 0.09);
  --violet: #7c5cff;
  --violet-soft: rgba(124, 92, 255, 0.18);
  --cyan: #35e7d7;
  --cyan-soft: rgba(53, 231, 215, 0.16);
  --text: #f3f1ff;
  --muted: #8892b0;
  --muted-dim: #5b6284;

  --font-display: "Space Grotesk", "Inter", sans-serif;
  --font-body: "Inter", sans-serif;
  --font-mono: "IBM Plex Mono", monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--void);
  color: var(--text);
  font-family: var(--font-body);
  -webkit-font-smoothing: antialiased;
}

body {
  min-height: 100vh;
  position: relative;
  overflow-x: hidden;
}

#starfield {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

main {
  position: relative;
  z-index: 1;
}

::selection { background: var(--violet-soft); color: var(--text); }

a, button, input { font-family: inherit; }

:focus-visible {
  outline: 2px solid var(--cyan);
  outline-offset: 3px;
}

/* ---------- Hero ---------- */

.hero {
  position: relative;
  min-height: 92vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 6rem 1.5rem 4rem;
  overflow: hidden;
}

#hero-wave {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0.55;
  z-index: 0;
}

.hero-inner {
  position: relative;
  z-index: 1;
  max-width: 640px;
  text-align: center;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  color: var(--cyan);
  margin: 0 0 1.25rem;
}

.hero h1 {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: clamp(2.4rem, 6vw, 3.6rem);
  line-height: 1.08;
  margin: 0 0 1.1rem;
  letter-spacing: -0.01em;
}

.hero h1 span {
  display: block;
  font-size: 0.42em;
  font-weight: 500;
  color: var(--muted);
  margin-top: 0.6em;
  letter-spacing: 0.01em;
}

.hero-sub {
  font-size: 1.02rem;
  line-height: 1.65;
  color: var(--muted);
  margin: 0 auto 2.5rem;
  max-width: 52ch;
}

.dropzone {
  border: 1.5px dashed var(--line);
  border-radius: 18px;
  padding: 2.4rem 1.5rem;
  cursor: pointer;
  transition: border-color 0.2s ease, background 0.2s ease;
  background: rgba(255, 255, 255, 0.02);
}

.dropzone:hover,
.dropzone:focus-visible,
.dropzone.dragover {
  border-color: var(--violet);
  background: var(--violet-soft);
}

.dropzone-glyph {
  color: var(--violet);
  width: 40px;
  height: 40px;
  margin: 0 auto 0.9rem;
}
.dropzone-glyph svg { width: 100%; height: 100%; }

.dropzone-label {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 500;
}
.dropzone-label span { color: var(--cyan); text-decoration: underline; text-underline-offset: 3px; }

.dropzone-hint {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted-dim);
}

.status-line {
  min-height: 1.4em;
  margin-top: 1.1rem;
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--muted);
}
.status-line.is-error { color: #ff8a8a; }

/* ---------- Dashboard ---------- */

.dashboard {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 1.5rem 6rem;
}

.dashboard.hidden { display: none; }

.filename-row {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--muted-dim);
  margin-bottom: 1.5rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}

.readouts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 1.25rem;
}

.readout-card {
  border-radius: 20px;
  padding: 1.8rem 1.8rem 1.5rem;
  border: 1px solid var(--line);
  position: relative;
  overflow: hidden;
}

.readout-bpm { background: linear-gradient(160deg, var(--violet-soft), var(--panel) 60%); }
.readout-key { background: linear-gradient(160deg, var(--cyan-soft), var(--panel) 60%); }

.readout-label {
  margin: 0 0 0.6rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--muted);
}

.readout-value {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-size: 2.6rem;
  font-weight: 600;
  line-height: 1;
}

.readout-unit {
  font-size: 0.42em;
  color: var(--muted);
  margin-left: 0.4rem;
  font-weight: 500;
}

.confidence-track {
  height: 5px;
  border-radius: 3px;
  background: rgba(255, 255, 255, 0.08);
  overflow: hidden;
  margin-bottom: 0.55rem;
}

.confidence-fill {
  height: 100%;
  width: 0%;
  border-radius: 3px;
  background: var(--violet);
  transition: width 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}
.readout-key .confidence-fill { background: var(--cyan); }

.readout-footnote {
  margin: 0;
  font-size: 0.8rem;
  color: var(--muted-dim);
}
.readout-footnote span { color: var(--muted); font-family: var(--font-mono); }

.candidate-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.9rem;
}

.candidate-chip {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text);
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.25rem 0.65rem;
}

.candidate-chip.is-primary {
  border-color: var(--violet);
  background: var(--violet-soft);
}
.readout-key .candidate-chip.is-primary {
  border-color: var(--cyan);
  background: var(--cyan-soft);
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: 16px;
  overflow: hidden;
  margin-bottom: 2.5rem;
}

.metric-card {
  background: var(--panel);
  padding: 1.15rem 1.2rem;
}

.metric-card .metric-label {
  margin: 0 0 0.5rem;
  font-size: 0.76rem;
  color: var(--muted);
}

.metric-card .metric-value {
  margin: 0;
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 500;
}

.metric-card .metric-value small {
  font-size: 0.65rem;
  color: var(--muted-dim);
  margin-left: 0.3rem;
}

.chart-section {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
}

.distortion-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.4rem 1.4rem 1.2rem;
  margin-bottom: 1.25rem;
}

.distortion-regions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  margin-top: 0.8rem;
}

.distortion-chip {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text);
  background: rgba(255, 138, 138, 0.14);
  border: 1px solid rgba(255, 138, 138, 0.3);
  border-radius: 999px;
  padding: 0.25rem 0.7rem;
}

.distortion-clean {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--cyan);
}

.chart-card {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 1.4rem 1.4rem 1rem;
}

.chart-card-wide { grid-column: 1 / -1; }

.chart-title {
  margin: 0 0 0.2rem;
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 600;
}

.chart-sub {
  margin: 0 0 1rem;
  font-size: 0.8rem;
  color: var(--muted);
}

.chart-card canvas { width: 100%; display: block; }

.chart-canvas-wrap {
  position: relative;
  width: 100%;
  height: 220px;
}

#chroma-canvas { height: 200px; }

/* ---------- Responsive ---------- */

@media (max-width: 760px) {
  .metric-grid { grid-template-columns: repeat(2, 1fr); }
  .chart-section { grid-template-columns: 1fr; }
  .readouts { grid-template-columns: 1fr; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; transition: none !important; }
}