:root {
  --bg: #0f1115;
  --panel: #181b22;
  --panel-2: #1f232c;
  --border: #2a2f3a;
  --text: #e6e8ee;
  --muted: #8a93a6;
  --accent: #4f8cff;
  --accent-2: #6ee7b7;
  --tool: #f0b67f;
  --error: #ff7a7a;
}

* { box-sizing: border-box; }

html, body {
  margin: 0; padding: 0; height: 100%;
  background: var(--bg); color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
  font-size: 14px;
}

body { display: flex; flex-direction: column; }

header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 20px; border-bottom: 1px solid var(--border);
  background: var(--panel);
}

header h1 { font-size: 16px; margin: 0; font-weight: 600; }
.tag {
  font-size: 11px; color: var(--muted); font-weight: 400;
  margin-left: 8px;
}

.controls { display: flex; gap: 12px; align-items: center; }
.controls label { font-size: 12px; color: var(--muted); display: flex; gap: 6px; align-items: center; }
.controls select, .controls button {
  background: var(--panel-2); color: var(--text);
  border: 1px solid var(--border); border-radius: 6px;
  padding: 4px 8px; font-size: 12px;
}
.controls button { cursor: pointer; }
.controls button:hover { background: var(--border); }

main {
  flex: 1; overflow-y: auto; padding: 20px;
  display: flex; flex-direction: column; gap: 12px;
  max-width: 900px; width: 100%; margin: 0 auto;
}

.msg {
  padding: 10px 14px; border-radius: 10px;
  background: var(--panel); border: 1px solid var(--border);
  max-width: 85%; word-wrap: break-word;
  line-height: 1.55;
}
.msg.user {
  align-self: flex-end; background: #1e2a44; border-color: #2a3a5e;
  white-space: pre-wrap;
}
.msg.assistant { align-self: flex-start; }
.msg.error { align-self: stretch; color: var(--error); border-color: #4a2424; }

/* Markdown content inside assistant bubbles */
.msg.assistant .md > *:first-child { margin-top: 0; }
.msg.assistant .md > *:last-child { margin-bottom: 0; }
.msg.assistant .md p { margin: 0.5em 0; }
.msg.assistant .md h1,
.msg.assistant .md h2,
.msg.assistant .md h3,
.msg.assistant .md h4 { margin: 0.8em 0 0.4em; font-weight: 600; }
.msg.assistant .md h1 { font-size: 1.3em; }
.msg.assistant .md h2 { font-size: 1.2em; }
.msg.assistant .md h3 { font-size: 1.1em; }
.msg.assistant .md ul,
.msg.assistant .md ol { padding-left: 1.5em; margin: 0.4em 0; }
.msg.assistant .md li { margin: 0.15em 0; }
.msg.assistant .md code {
  background: var(--panel-2); padding: 1px 5px; border-radius: 4px;
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.9em;
}
.msg.assistant .md pre {
  background: var(--panel-2); padding: 10px 12px; border-radius: 6px;
  overflow-x: auto; margin: 0.6em 0;
  border: 1px solid var(--border);
}
.msg.assistant .md pre code { background: transparent; padding: 0; }
.msg.assistant .md blockquote {
  border-left: 3px solid var(--border); padding-left: 10px;
  color: var(--muted); margin: 0.5em 0;
}
.msg.assistant .md a { color: var(--accent); }
.msg.assistant .md table {
  border-collapse: collapse; margin: 0.5em 0;
}
.msg.assistant .md th,
.msg.assistant .md td {
  border: 1px solid var(--border); padding: 4px 8px;
}
.msg.assistant .md th { background: var(--panel-2); }
.msg.assistant .md hr {
  border: none; border-top: 1px solid var(--border); margin: 0.8em 0;
}

/* Thinking indicator */
.thinking {
  align-self: flex-start;
  display: flex; gap: 6px; align-items: center;
  padding: 12px 14px; border-radius: 10px;
  background: var(--panel); border: 1px solid var(--border);
  color: var(--muted); font-size: 12px;
}
.thinking .dots { display: inline-flex; gap: 4px; }
.thinking .dots span {
  width: 6px; height: 6px; border-radius: 50%;
  background: var(--accent);
  animation: pulse 1.2s ease-in-out infinite;
}
.thinking .dots span:nth-child(2) { animation-delay: 0.18s; }
.thinking .dots span:nth-child(3) { animation-delay: 0.36s; }
@keyframes pulse {
  0%, 80%, 100% { opacity: 0.25; transform: scale(0.85); }
  40%           { opacity: 1;    transform: scale(1.05); }
}

.role { font-size: 11px; color: var(--muted); margin-bottom: 4px; text-transform: uppercase; letter-spacing: 0.05em; }

footer {
  border-top: 1px solid var(--border); background: var(--panel);
  padding: 12px 20px;
}

#composer {
  display: flex; gap: 8px; max-width: 900px; margin: 0 auto;
}
#input {
  flex: 1; resize: vertical; min-height: 44px; max-height: 200px;
  background: var(--panel-2); color: var(--text);
  border: 1px solid var(--border); border-radius: 8px;
  padding: 10px 12px; font-family: inherit; font-size: 14px;
}
#send {
  background: var(--accent); color: white; border: none; border-radius: 8px;
  padding: 0 18px; cursor: pointer; font-weight: 600;
}
#send:disabled { background: var(--border); color: var(--muted); cursor: not-allowed; }

.hint {
  font-size: 11px; color: var(--muted); margin-top: 6px; max-width: 900px;
  margin-left: auto; margin-right: auto;
}