:root {
  --bg: #0f1115;
  --panel: #171a21;
  --line: #2a3040;
  --text: #e8ecf4;
  --muted: #8b95a8;
  --accent: #6ea8ff;
  --danger: #ff6b6b;
}
* { box-sizing: border-box; }
html, body { margin: 0; height: 100%; background: var(--bg); color: var(--text); font: 14px/1.45 ui-sans-serif, system-ui, sans-serif; }
button, input { font: inherit; }
button { cursor: pointer; }
a { color: var(--accent); }
.app { display: flex; height: 100%; }
.sidebar { width: 280px; border-right: 1px solid var(--line); background: var(--panel); padding: 16px; overflow: auto; }
.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }
.embed .sidebar { display: none; }
.header { padding: 12px 16px; border-bottom: 1px solid var(--line); display: flex; justify-content: space-between; align-items: center; }
.messages { flex: 1; overflow: auto; padding: 16px; }
.composer { display: flex; gap: 8px; padding: 12px 16px; border-top: 1px solid var(--line); }
.composer input { flex: 1; background: #11141b; color: var(--text); border: 1px solid var(--line); border-radius: 8px; padding: 10px 12px; }
.composer button, .sidebar button, .login button { background: var(--accent); color: #081018; border: 0; border-radius: 8px; padding: 8px 12px; font-weight: 600; }
.msg { margin: 0 0 12px; white-space: pre-wrap; }
.msg.user { color: #c5d4ff; }
.msg.assistant { color: var(--text); }
.muted { color: var(--muted); }
.item { padding: 8px; border-radius: 8px; cursor: pointer; }
.item.active, .item:hover { background: #1f2430; }
.login { max-width: 400px; margin: 12vh auto; background: var(--panel); padding: 28px 24px; border-radius: 12px; border: 1px solid var(--line); }
.login input { width: 100%; margin: 8px 0 12px; padding: 10px; border-radius: 8px; border: 1px solid var(--line); background: #11141b; color: var(--text); }
.error { color: var(--danger); }
h1, h2 { font-size: 16px; margin: 0 0 12px; }
.brand-logo { width: 34px; height: 34px; object-fit: contain; flex: none; }
.welcome-headline { display: flex; align-items: center; justify-content: center; gap: 10px; margin: 0 0 16px; }
.welcome-headline.stacked { flex-direction: column; gap: 16px; }
.welcome-headline.stacked .brand-logo { width: 72px; height: 72px; }
.welcome-slogan { font-size: 26px; line-height: 32px; font-weight: 500; letter-spacing: -0.02em; text-align: center; }
.main.welcome { justify-content: center; align-items: center; padding: 24px 16px 40px; }
.welcome-hero { display: flex; flex-direction: column; align-items: stretch; width: min(720px, 100%); gap: 20px; }
.main.welcome .welcome-body { flex: none; display: flex; flex-direction: column; align-items: center; padding: 0; overflow: visible; }
.main.welcome .welcome-headline { margin: 0; }
.main.welcome .composer { border-top: 0; width: 100%; margin: 0; flex-wrap: nowrap; }