:root {
  color-scheme: dark;
  --bg: #03050a;
  --panel: #0b1320;
  --line: #1f9aff;
  --line-soft: #1f9aff55;
  --text: #d9eeff;
  --muted: #8aa2b8;
}

* { box-sizing: border-box; -webkit-user-select: none; user-select: none; }

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", system-ui, sans-serif;
  background:
    radial-gradient(circle at center, #0a1a2e 0%, #03050a 55%),
    linear-gradient(135deg, #03050a, #060d18);
  color: var(--text);
}

/* ── Layout ─────────────────────────────────────────────── */

.layout {
  display: grid;
  grid-template-columns: 1.2fr 1fr 1fr;
  gap: 1rem;
  padding: 1rem;
  align-items: start;
}

.panel {
  background: linear-gradient(180deg, #0e1828cc, #090f1acc);
  border: 1px solid var(--line-soft);
  border-radius: 14px;
  padding: 1rem;
  box-shadow: 0 0 20px #0d3b6a55 inset, 0 0 20px #0d3b6a30;
}

/* ── Typography ─────────────────────────────────────────── */

h1, h2, h3 { margin: 0; letter-spacing: 0.08em; }
h1 { font-size: 1.8rem; text-align: center; color: #7ec7ff; margin-bottom: 0.75rem; }
h2 { font-size: 1.1rem; color: #95d5ff; }
h3 { font-size: 0.95rem; color: #95d5ff; }

/* ── Visual panel ───────────────────────────────────────── */

.visual-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
}

#visualizer {
  width: min(100%, 560px);
  height: auto;
  border-radius: 50%;
  filter: drop-shadow(0 0 20px #1f9aff88);
}

.status {
  margin-top: 0.5rem;
  color: #92d9ff;
}

/* PTT and transcript anchored to bottom of visual panel */

.ptt {
  width: 100%;
  max-width: 320px;
  margin-top: 1.25rem;
  font-size: 1rem;
  font-weight: 600;
  border-color: #5db7ff;
  user-select: none;
  -webkit-user-select: none;
  touch-action: none;
  -webkit-touch-callout: none;
  padding: 0.9rem;
  border-radius: 10px;
  border: 1px solid #5db7ff;
  background: linear-gradient(180deg, #0d2e4a, #0a1f34);
  color: var(--text);
  cursor: pointer;
}

.ptt:hover { border-color: #88ccff; }

.ptt.active {
  background: linear-gradient(180deg, #174f7d, #123c60);
  box-shadow: 0 0 12px #47acff88;
}

.ptt-hint {
  margin: 0.4rem 0 0;
}

.transcript-wrap {
  width: 100%;
  margin-top: 0.8rem;
  border-top: 1px solid #1f3550;
  padding-top: 0.7rem;
}

#transcript { color: #bfe6ff; margin: 0; min-height: 1.5rem; -webkit-user-select: text; user-select: text; }

/* ── Collapsible panels ─────────────────────────────────── */

.collapse-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: none;
  border: none;
  padding: 0 0 0.6rem;
  margin: 0;
  cursor: pointer;
  border-bottom: 1px solid #1f3550;
  margin-bottom: 0.75rem;
  border-radius: 0;
}

.collapse-toggle:hover { border-color: #58b6ff; }
.collapse-toggle:hover .collapse-heading { color: #c8ecff; }

.collapse-heading {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--label);
  margin: 0;
}

.chevron {
  font-size: 0.7rem;
  color: var(--muted);
  transition: transform 0.25s ease;
  display: inline-block;
}

.collapse-toggle[aria-expanded="false"] .chevron {
  transform: rotate(180deg);
}

.collapsible-body {
  overflow: hidden;
  transition: max-height 0.3s ease, opacity 0.3s ease;
  max-height: 2000px;
  opacity: 1;
}

.collapsible-body.collapsed {
  max-height: 0;
  opacity: 0;
  margin-bottom: 0;
}

/* ── Form controls ──────────────────────────────────────── */

.controls-panel label {
  display: block;
  margin-bottom: 0.8rem;
  color: var(--muted);
  font-size: 0.9rem;
}

input, select, button {
  width: 100%;
  margin-top: 0.35rem;
  border-radius: 10px;
  border: 1px solid #2b5275;
  background: #081424;
  color: var(--text);
  padding: 0.65rem 0.75rem;
}

button {
  cursor: pointer;
  background: linear-gradient(180deg, #0d2e4a, #0a1f34);
}

button:hover { border-color: #58b6ff; }
button:disabled { opacity: 0.6; cursor: not-allowed; }

.inline {
  display: flex !important;
  align-items: center;
  gap: 0.6rem;
}

.inline input[type="checkbox"] {
  width: auto;
  margin-top: 0;
}

.row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.6rem;
  margin-bottom: 0.8rem;
}

.hint {
  margin: 0.45rem 0 0.9rem;
  color: var(--muted);
  font-size: 0.85rem;
}

/* ── Chat ───────────────────────────────────────────────── */

.chat {
  min-height: 200px;
  max-height: 65vh;
  overflow: auto;
  border: 1px solid #1f3550;
  border-radius: 10px;
  padding: 0.75rem;
  background: #06101d88;
  -webkit-user-select: text;
  user-select: text;
}

.msg {
  margin-bottom: 0.6rem;
  padding: 0.6rem;
  border-radius: 8px;
  line-height: 1.4;
}

.msg.user { background: #12314c; }
.msg.assistant { background: #0f2338; border: 1px solid #23537d; }
.msg.system { background: #241a1a; border: 1px solid #6e3a3a; color: #ffd8d8; }

/* ── Responsive ─────────────────────────────────────────── */

@media (max-width: 1100px) {
  .layout {
    grid-template-columns: 1fr 1fr;
  }
  .visual-panel {
    grid-column: 1 / -1;
  }
}

@media (max-width: 640px) {
  .layout {
    grid-template-columns: 1fr;
    padding: 0.5rem;
    gap: 0.6rem;
  }
  .visual-panel { grid-column: auto; }
  #visualizer { width: min(100%, 300px); }
  .ptt { max-width: 100%; font-size: 1.1rem; padding: 1rem; }
  .chat { max-height: 50vh; }
  h1 { font-size: 1.4rem; }
}