* { box-sizing: border-box; }
:root {
  --bg: #0e0f10; --panel: #141517; --border: #2a2b2e; --text: #e6e7e9; --muted: #a9abb0;
  --primary: #10a37f; --primary-ink: #062e26;
}
html, body { height: 100%; }
body {
  margin: 0; background: var(--bg); color: var(--text); font: 14px/1.5 Inter, system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
}
#app { display: grid; grid-template-columns: 280px 1fr; height: 100vh; }
.sidebar { border-right: 1px solid var(--border); background: var(--panel); display: flex; flex-direction: column; }
.sidebar-header { padding: 12px; border-bottom: 1px solid var(--border); }
.threads { overflow: auto; padding: 8px; }
.thread { padding: 10px 12px; border-radius: 8px; cursor: pointer; color: var(--text); border: 1px solid transparent; }
.thread:hover { background: #1a1c1f; }
.thread.active { background: #1a1c1f; border-color: var(--border); }

.chat { display: grid; grid-template-rows: auto 1fr auto; }
.chat-header { display: flex; align-items: center; justify-content: space-between; padding: 12px 16px; border-bottom: 1px solid var(--border); }
.title { font-weight: 600; }
.messages { padding: 16px; overflow: auto; }
.message { display: grid; grid-template-columns: 60px 1fr; gap: 12px; padding: 12px 0; border-bottom: 1px solid rgba(255,255,255,0.05); }
.message .avatar { width: 36px; height: 36px; border-radius: 50%; background: #1f2226; display: flex; align-items: center; justify-content: center; font-weight: 700; color: var(--muted); }
.message .role { font-size: 12px; color: var(--muted); }
.message .content { white-space: pre-wrap; }

.composer { display: grid; grid-template-columns: 1fr auto; gap: 8px; padding: 12px; border-top: 1px solid var(--border); background: var(--panel); }
#input { width: 100%; resize: none; background: #1a1c1f; color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 10px 12px; max-height: 160px; }
.composer-actions { display: flex; gap: 8px; align-items: center; }

.btn { background: #1a1c1f; color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 8px 12px; cursor: pointer; }
.btn:hover { filter: brightness(1.05); }
.btn.primary { background: var(--primary); color: #fff; border-color: #0d8f6f; }
.btn[disabled] { opacity: 0.6; cursor: not-allowed; }

.settings { position: fixed; right: 12px; top: 12px; width: 320px; background: var(--panel); border: 1px solid var(--border); border-radius: 10px; padding: 12px; box-shadow: 0 10px 30px rgba(0,0,0,0.35); }
.settings.hidden { display: none; }
.field { display: grid; gap: 6px; margin-bottom: 10px; }
.field textarea, .field input { background: #1a1c1f; color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 8px; }
.note { color: var(--muted); font-size: 12px; }

@media (max-width: 860px) {
  #app { grid-template-columns: 1fr; }
  .sidebar { display: none; }
}