:root {
  --bg: #0d1117;
  --panel: #161b22;
  --border: #30363d;
  --text: #e6edf3;
  --muted: #8b949e;
  --accent: #58a6ff;
  --user-bg: #1f6feb22;
  --assistant-bg: #161b22;
  --tool-bg: #2d1117;
  --think-bg: #1a2332;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: system-ui, "Segoe UI", sans-serif;
  font-size: 15px;
}

body {
  display: flex;
  flex-direction: column;
  height: 100vh;
}

header {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 10px 16px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
}

header h1 {
  font-size: 18px;
  margin: 0;
}

.controls {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
}

select, button, input[type="checkbox"] {
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 4px 8px;
  font-size: 14px;
}

button { cursor: pointer; }
button:hover { border-color: var(--accent); }

.think-toggle { display: flex; align-items: center; gap: 4px; color: var(--muted); }

main#chat {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.message {
  max-width: 860px;
  width: 100%;
  margin: 0 auto;
  padding: 12px 14px;
  border-radius: 10px;
  border: 1px solid var(--border);
  line-height: 1.6;
}

.message.user { background: var(--user-bg); }
.message.assistant { background: var(--assistant-bg); }
.message .role { font-weight: 600; margin-bottom: 6px; color: var(--muted); }

.message pre {
  background: #010409;
  border-radius: 8px;
  padding: 10px;
  overflow-x: auto;
}

.message code { font-family: "SFMono-Regular", Consolas, monospace; font-size: 13px; }
.message p { margin: 8px 0; }
.message ul, .message ol { padding-left: 22px; }

.tool {
  max-width: 860px;
  width: 100%;
  margin: 0 auto;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px dashed var(--border);
  background: var(--tool-bg);
  color: var(--muted);
  font-size: 13px;
}

.tool .name { color: var(--accent); font-weight: 600; }
.tool .args, .tool .result { color: var(--muted); white-space: pre-wrap; word-break: break-word; }
.tool details summary { cursor: pointer; color: var(--accent); }

.thinking {
  max-width: 860px;
  width: 100%;
  margin: 0 auto;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--think-bg);
  color: var(--muted);
  font-size: 13px;
}
.thinking summary { cursor: pointer; color: var(--accent); }

form#input-form {
  display: flex;
  gap: 8px;
  padding: 12px 16px;
  background: var(--panel);
  border-top: 1px solid var(--border);
}

textarea#input {
  flex: 1;
  resize: none;
  background: var(--bg);
  color: var(--text);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px;
  font-size: 15px;
  font-family: inherit;
}

button#send-btn { padding: 0 20px; }