Hi Ma,
You can create a custom class in your sass files to add to your datagrid.
.datagrid-noheader.mx-datagrid {
.mx-datagrid-head-table {
display: none;
}
}
To add the class to the datagrid go to properties > common
also here is the documentation for styling
https://docs.mendix.com/howto6/setup-mendix-ui-framework-with-koala
Hope this helps!