:root {
  color-scheme: light dark;
  --bg: #0d0d0f;
  --fg: #f2f0ea;
  --accent: #d4af37;
  --card: #17171a;
  --muted: #9a978d;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--fg);
  height: 100vh;
}

.hidden { display: none !important; }

.screen { height: 100vh; display: flex; align-items: center; justify-content: center; }

.card {
  background: var(--card);
  border: 1px solid #2a2a2e;
  border-radius: 12px;
  padding: 2rem;
  max-width: 420px;
  text-align: center;
}

#app { display: flex; flex-direction: column; }

header {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid #2a2a2e;
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
}

header h1 { margin: 0; color: var(--accent); font-size: 1.25rem; }
.subtitle { color: var(--muted); font-size: 0.85rem; }

#chat {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.msg {
  max-width: 75%;
  padding: 0.6rem 0.9rem;
  border-radius: 10px;
  line-height: 1.4;
  white-space: pre-wrap;
}

.msg.user { align-self: flex-end; background: var(--accent); color: #0d0d0f; }
.msg.assistant { align-self: flex-start; background: var(--card); border: 1px solid #2a2a2e; }
.msg.system { align-self: center; color: var(--muted); font-size: 0.85rem; }

form {
  display: flex;
  gap: 0.5rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid #2a2a2e;
}

input {
  flex: 1;
  padding: 0.7rem 1rem;
  border-radius: 8px;
  border: 1px solid #2a2a2e;
  background: #0d0d0f;
  color: var(--fg);
  font-size: 1rem;
}

button {
  padding: 0.7rem 1.2rem;
  border-radius: 8px;
  border: none;
  background: var(--accent);
  color: #0d0d0f;
  font-weight: 600;
  cursor: pointer;
}

button:disabled { opacity: 0.5; cursor: not-allowed; }