:root {
  --bg: #f7f7f5;
  --surface: #ffffff;
  --text: #1d1d1f;
  --muted: #6e6e73;
  --border: #e3e3e0;
  --accent: #3b6cf6;
  --accent-text: #ffffff;
  --user-bg: #3b6cf6;
  --user-text: #ffffff;
  --code-bg: #f0f0ed;
  --ok: #22a356;
  --bad: #d64545;
  --radius: 14px;
  color-scheme: light dark;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #131315;
    --surface: #1d1d20;
    --text: #ececef;
    --muted: #9a9aa2;
    --border: #2c2c31;
    --accent: #6b8fff;
    --user-bg: #3d5fd9;
    --code-bg: #26262b;
  }
}

* { box-sizing: border-box; }

html, body { height: 100%; margin: 0; }

body {
  display: grid;
  grid-template-rows: auto 1fr auto;
  max-width: 820px;
  margin: 0 auto;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
}

header {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
}
header h1 { font-size: 1.05rem; margin: 0; flex: 1; }
header form { margin: 0; }

.health { display: flex; align-items: center; gap: 6px; font-size: .85rem; color: var(--muted); }
.dot { width: 8px; height: 8px; border-radius: 50%; background: var(--muted); }
.dot.ok { background: var(--ok); }
.dot.bad { background: var(--bad); }

#messages {
  overflow-y: auto;
  padding: 20px 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.empty { margin: auto; text-align: center; color: var(--muted); }
.empty .big { font-size: 2rem; margin: 0; }
.empty:not(:only-child) { display: none; }

.msg { display: flex; }
.msg.user { justify-content: flex-end; }

.bubble {
  max-width: min(85%, 680px);
  padding: 10px 14px;
  border-radius: var(--radius);
  background: var(--surface);
  border: 1px solid var(--border);
  overflow-wrap: anywhere;
}
.msg.user .bubble {
  background: var(--user-bg);
  color: var(--user-text);
  border-color: transparent;
  border-bottom-right-radius: 4px;
}
.msg.assistant .bubble { border-bottom-left-radius: 4px; }

.content.plain { white-space: pre-wrap; }
.markdown > :first-child { margin-top: 0; }
.markdown > :last-child { margin-bottom: 0; }
.markdown pre {
  background: var(--code-bg);
  padding: 10px 12px;
  border-radius: 8px;
  overflow-x: auto;
  font-size: .9em;
  tab-size: 4;
}
.markdown code { font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; }
.markdown :not(pre) > code { background: var(--code-bg); padding: 1px 5px; border-radius: 5px; font-size: .9em; }
.markdown table { border-collapse: collapse; }
.markdown th, .markdown td { border: 1px solid var(--border); padding: 4px 8px; }
.markdown a { color: var(--accent); }

.error { color: var(--bad); font-size: .9rem; margin: 6px 0 0; }

/* typing indicator while waiting for the first token */
.streaming:empty::after {
  content: "● ● ●";
  letter-spacing: 2px;
  color: var(--muted);
  animation: pulse 1.2s ease-in-out infinite;
}
@keyframes pulse { 50% { opacity: .3; } }

#composer {
  display: flex;
  gap: 8px;
  padding: 12px 16px 18px;
  border-top: 1px solid var(--border);
}
#composer textarea {
  flex: 1;
  resize: none;
  max-height: 200px;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--surface);
  color: var(--text);
  font: inherit;
}
#composer textarea:focus { outline: 2px solid var(--accent); outline-offset: -1px; }

button {
  padding: 0 18px;
  border: 0;
  border-radius: var(--radius);
  background: var(--accent);
  color: var(--accent-text);
  font: inherit;
  font-weight: 600;
  cursor: pointer;
}
button:disabled { opacity: .5; cursor: progress; }
button.ghost {
  padding: 6px 12px;
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--border);
  font-weight: 500;
  font-size: .85rem;
}