body{background:#f4f6fb;font-family:system-ui}
.navbar-brand{font-weight:700;letter-spacing:.3px}
.brand-nav{background:#111827}
.stat-card{border-radius:14px;border:0;box-shadow:0 6px 18px rgba(0,0,0,.08)}
.chat-bubble{max-width:70%;padding:10px 14px;border-radius:14px;margin-bottom:10px}
.chat-user{background:#2563eb;color:#fff;margin-left:auto}
.chat-agent{background:#e5e7eb}
.attach-item{padding:6px;border:1px solid #eee;border-radius:8px;margin-bottom:6px;background:#fff}