html, body { margin: 0; font-family: Segoe UI, Arial, sans-serif; background: #f4f6f8; color: #222; }
.top { background: #1f3b57; color: #fff; padding: 10px 16px; font-weight: 600; }
.page { max-width: 900px; margin: 16px auto; padding: 0 16px; }
.err { color: #b00020; }