:root {
  --bg: #0b1021;
  --panel: #121735;
  --text: #e6e9f4;
  --muted: #aab1c7;
  --accent: #5b8cff;
  --accent-2: #7aa2ff;
  --user: #1f294a;
  --assistant: #18223f;
  --border: #2a3158;
}

* { box-sizing: border-box; }
html, body { height: 100%; }
body {
  margin: 0;
  background: radial-gradient(1000px 800px at 20% -10%, #1b2a5b 0%, transparent 60%),
              radial-gradient(1200px 900px at 120% 10%, #0e7acb 0%, transparent 55%),
              var(--bg);
  color: var(--text);
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Inter, "Apple Color Emoji", "Segoe UI Emoji";
}

.app {
  display: grid;
  grid-template-rows: auto 1fr auto;
  height: 100%;
}

.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  background: linear-gradient(180deg, rgba(18, 23, 53, 0.9), rgba(18, 23, 53, 0.7));
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(6px);
}

.header h1 {
  margin: 0;
  font-size: 18px;
  letter-spacing: 0.3px;
}

.controls {
  display: flex;
  align-items: center;
  gap: 10px;
}

.mode-label {
  font-size: 12px;
  color: var(--muted);
}

.mode-select {
  padding: 6px 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: #0c1431;
  color: var(--text);
}

.status {
  color: var(--muted);
  font-size: 12px;
}

.main {
  padding: 16px;
  overflow: hidden;
}

.messages {
  height: 100%;
  overflow-y: auto;
  padding-right: 4px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.msg {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  max-width: 900px;
}

.bubble {
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  line-height: 1.5;
  white-space: pre-wrap;
}

.user .bubble {
  background: linear-gradient(180deg, var(--user), rgba(31,41,74,0.7));
}
.assistant .bubble {
  background: linear-gradient(180deg, var(--assistant), rgba(24,34,63,0.7));
}

.assistant.typing .bubble {
  border-style: dashed;
  opacity: 0.9;
}

.role {
  font-size: 11px;
  color: var(--muted);
  margin-bottom: 4px;
}

.footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  background: linear-gradient(180deg, rgba(18, 23, 53, 0.7), rgba(18, 23, 53, 0.6));
  backdrop-filter: blur(6px);
}

.chat-form {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 8px;
}

.chat-input {
  width: 100%;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #0c1431;
  color: var(--text);
  outline: none;
}
.chat-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(91, 140, 255, 0.2);
}

.send-btn {
  padding: 10px 16px;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: linear-gradient(180deg, var(--accent), var(--accent-2));
  color: white;
  font-weight: 600;
  cursor: pointer;
}
.send-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.hint {
  color: var(--muted);
  font-size: 12px;
  margin-top: 4px;
}