:root {
  --bg: #f7f6f3;
  --panel: #ffffff;
  --ink: #1c1b19;
  --ink-soft: #6b6862;
  --line: #e2dfd8;
  --accent: #b4531f;
  --accent-soft: #fdf0e6;
  --math: #1f5673;
  --math-soft: #eaf2f7;
  --focus: #ffd9a8;
  --radius: 10px;
  --mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #16171a;
    --panel: #1e2024;
    --ink: #e9e7e3;
    --ink-soft: #9b978f;
    --line: #32353b;
    --accent: #e8894f;
    --accent-soft: #35251a;
    --math: #7fb6d6;
    --math-soft: #1b2a33;
    --focus: #5a4327;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 2rem 1.5rem 3rem;
  background: var(--bg);
  color: var(--ink);
  font: 16px/1.6 ui-sans-serif, system-ui, -apple-system, "Segoe UI", sans-serif;
}

header { max-width: 1200px; margin: 0 auto 1.75rem; }

h1 {
  margin: 0;
  font-size: 1.9rem;
  font-weight: 650;
  letter-spacing: -0.02em;
}
h1 span { color: var(--accent); }

.tagline {
  margin: 0.4rem 0 0;
  color: var(--ink-soft);
  max-width: 62ch;
}

main {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  align-items: start;
}

@media (max-width: 900px) {
  main { grid-template-columns: 1fr; }
}

.pane {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 1rem 1.1rem 1.1rem;
}

.pane-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

.pane-head h2 {
  margin: 0;
  font-size: 0.78rem;
  font-weight: 650;
  text-transform: uppercase;
  letter-spacing: 0.09em;
  color: var(--ink-soft);
}

.pane-actions { display: flex; gap: 0.75rem; }

#seg-count { font-size: 0.8rem; color: var(--ink-soft); }

/* ---- input ---- */

#drop-zone { position: relative; }

textarea {
  width: 100%;
  min-height: 340px;
  resize: vertical;
  padding: 0.85rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--bg);
  color: var(--ink);
  font: 13px/1.65 var(--mono);
  tab-size: 2;
}

textarea:focus-visible,
#segments:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 1px;
}

#drop-hint {
  position: absolute;
  inset: 0;
  display: none;
  place-items: center;
  border: 2px dashed var(--accent);
  border-radius: 8px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 600;
  pointer-events: none;
}

#drop-zone.dragging #drop-hint { display: grid; }

.pane-foot {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-top: 0.85rem;
}

/* ---- buttons ---- */

button, .file-btn {
  font: inherit;
  font-size: 0.9rem;
  padding: 0.5rem 0.95rem;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
}

button:hover:not(:disabled), .file-btn:hover { border-color: var(--accent); }
button:disabled { opacity: 0.45; cursor: default; }

button.primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  font-weight: 600;
}
button.primary:hover:not(:disabled) { filter: brightness(1.08); }

.link-btn {
  border: none;
  background: none;
  padding: 0;
  font-size: 0.8rem;
  color: var(--ink-soft);
  text-decoration: underline;
}
.link-btn:hover { color: var(--accent); }

.file-btn { position: relative; overflow: hidden; }
.file-btn input { position: absolute; inset: 0; opacity: 0; cursor: pointer; }

#read-btn { margin-left: auto; }

.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin-top: 0.6rem;
}
.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  padding: 0.2rem 0.3rem 0.2rem 0.6rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  font-size: 0.8rem;
  color: var(--ink-soft);
  background: var(--panel);
}
.chip-x {
  padding: 0 0.4rem;
  border: none;
  background: none;
  font-size: 1rem;
  line-height: 1;
  color: var(--ink-soft);
}
.chip-x:hover { color: var(--accent); }

#status {
  margin: 0.7rem 0 0;
  min-height: 1.2em;
  font-size: 0.85rem;
  color: var(--ink-soft);
}
#status.error { color: #c0392b; }
@media (prefers-color-scheme: dark) { #status.error { color: #ff8a75; } }

/* ---- controls ---- */

#controls {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1.25rem;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 0.85rem;
  margin-bottom: 0.5rem;
  border-bottom: 1px solid var(--line);
}

.transport { display: flex; gap: 0.4rem; }

.tuning {
  display: flex;
  gap: 1rem;
  align-items: center;
  flex-wrap: wrap;
}

.tuning label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.78rem;
  color: var(--ink-soft);
}

select {
  font: inherit;
  font-size: 0.8rem;
  padding: 0.3rem 0.4rem;
  max-width: 190px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--panel);
  color: var(--ink);
}

input[type=range] { width: 110px; accent-color: var(--accent); }
#rate-out { font-variant-numeric: tabular-nums; }

/* ---- segments ---- */

#segments {
  max-height: 60vh;
  overflow-y: auto;
  scroll-behavior: smooth;
}

.empty {
  color: var(--ink-soft);
  font-size: 0.9rem;
  margin: 0;
  padding: 1.5rem 0.25rem;
}

.seg {
  padding: 0.45rem 0.6rem;
  margin-bottom: 0.15rem;
  border-radius: 7px;
  border-left: 3px solid transparent;
  cursor: pointer;
  transition: background 0.12s ease;
}

.seg:hover { background: var(--focus); }

.seg.speaking {
  background: var(--accent-soft);
  border-left-color: var(--accent);
}

.seg.spoken { opacity: 0.5; }

.seg-heading {
  font-weight: 650;
  font-size: 1.02rem;
  margin-top: 0.9rem;
}
.seg-heading:first-child { margin-top: 0; }

.seg-label { font-weight: 600; font-style: italic; }

.seg-display_math {
  background: var(--math-soft);
  border-left-color: var(--math);
  color: var(--math);
}
.seg-display_math.speaking {
  background: var(--accent-soft);
  border-left-color: var(--accent);
  color: var(--ink);
}

.seg .tex {
  display: block;
  margin-top: 0.3rem;
  font: 11.5px/1.5 var(--mono);
  color: var(--ink-soft);
  white-space: pre-wrap;
  word-break: break-word;
}