:root {
  --bg: #0f172a;
  --panel: #111827;
  --panel-2: #1f2937;
  --text: #e5e7eb;
  --muted: #94a3b8;
  --accent: #22d3ee;
  --accent-2: #06b6d4;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 20% 10%, #164e63 0%, transparent 35%),
    radial-gradient(circle at 80% 90%, #0c4a6e 0%, transparent 35%),
    var(--bg);
  display: grid;
  place-items: center;
  padding: 16px;
}

.app {
  width: min(900px, 100%);
  background: linear-gradient(145deg, var(--panel), var(--panel-2));
  border: 1px solid #334155;
  border-radius: 16px;
  padding: 20px;
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.45);
}

.top h1 {
  margin: 0;
  font-size: 2rem;
}

.top p {
  margin: 6px 0 0;
  color: var(--muted);
}

.messages {
  margin-top: 16px;
  height: 350px;
  overflow: auto;
  border: 1px solid #334155;
  border-radius: 12px;
  padding: 12px;
  background: rgba(15, 23, 42, 0.6);
}

.msg {
  margin: 8px 0;
  padding: 10px 12px;
  border-radius: 10px;
  line-height: 1.35;
}

.msg.user {
  background: #1d4ed8;
}

.msg.assistant {
  background: #0f766e;
}

.controls {
  margin-top: 14px;
}

.row {
  display: flex;
  gap: 10px;
  margin-bottom: 10px;
}

.btn,
.input,
.select {
  border-radius: 10px;
  border: 1px solid #334155;
  padding: 10px 12px;
  font-size: 1rem;
}

.btn {
  background: #111827;
  color: var(--text);
  cursor: pointer;
}

.btn:hover {
  border-color: #64748b;
}

.btn.primary {
  background: linear-gradient(90deg, var(--accent-2), var(--accent));
  color: #06202a;
  font-weight: 700;
  border: none;
}

.btn:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}

.input {
  flex: 1;
  background: #0f172a;
  color: var(--text);
}

.select {
  background: #0f172a;
  color: var(--text);
}

.status {
  margin: 0;
  color: var(--muted);
}

.player {
  width: 100%;
  margin-top: 12px;
}

@media (max-width: 640px) {
  .row {
    flex-direction: column;
  }
}