:root {
  --bg: #f4f5f7;
  --panel: #ffffff;
  --border: #e0e3e8;
  --accent: #007a3d;
  --accent-dark: #005f2f;
  --user-bubble: #007a3d;
  --assistant-bubble: #eef0f3;
  --text: #1c1e21;
  --muted: #6b7078;
  --error: #b3261e;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  background: var(--bg);
  color: var(--text);
}

.chat {
  max-width: 780px;
  margin: 0 auto;
  height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--panel);
  border-left: 1px solid var(--border);
  border-right: 1px solid var(--border);
}

.chat__header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}

.chat__header h1 {
  font-size: 1.1rem;
  margin: 0;
}

.chat__controls {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 0.85rem;
  color: var(--muted);
}

.chat__controls select,
.chat__controls button {
  font-size: 0.85rem;
  padding: 4px 8px;
  border: 1px solid var(--border);
  border-radius: 6px;
  background: var(--panel);
  cursor: pointer;
}

.chat__messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.msg {
  max-width: 80%;
  padding: 10px 14px;
  border-radius: 14px;
  line-height: 1.45;
  white-space: pre-wrap;
  word-wrap: break-word;
}

.msg--user {
  align-self: flex-end;
  background: var(--user-bubble);
  color: #fff;
  border-bottom-right-radius: 4px;
}

.msg--assistant {
  align-self: flex-start;
  background: var(--assistant-bubble);
  color: var(--text);
  border-bottom-left-radius: 4px;
}

.msg--loading {
  color: var(--muted);
  font-style: italic;
}

.chat__error {
  margin: 0 20px 8px;
  padding: 8px 12px;
  background: #fdecea;
  color: var(--error);
  border: 1px solid #f5c6c2;
  border-radius: 8px;
  font-size: 0.9rem;
}

.chat__composer {
  display: flex;
  gap: 8px;
  padding: 12px 20px 20px;
  border-top: 1px solid var(--border);
}

.chat__composer textarea {
  flex: 1;
  resize: none;
  padding: 10px 12px;
  border: 1px solid var(--border);
  border-radius: 10px;
  font: inherit;
  max-height: 140px;
  overflow-y: auto;
}

.chat__composer button {
  padding: 0 20px;
  border: none;
  border-radius: 10px;
  background: var(--accent);
  color: #fff;
  font-weight: 600;
  cursor: pointer;
}

.chat__composer button:hover {
  background: var(--accent-dark);
}

.chat__composer button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}