It's state, not config.

internal/dnsmasq/config_modular.go

@@ -62,11 +62,7 @@ log-dhcp
 		}
 		fmt.Fprintf(&sb, "dhcp-range=%s,%s,%s\n", dhcp.RangeStart, dhcp.RangeEnd, leaseTime)
 
-		// Gateway: use explicit DHCP gateway, fall back to router IP
 		gateway := dhcp.Gateway
-		if gateway == "" {
-			gateway = cfg.Cloud.Router.IP
-		}
 		if gateway != "" {
 			fmt.Fprintf(&sb, "dhcp-option=3,%s\n", gateway) // default gateway
 		}