Flow (Vaadin 10) Bar Chart (Charts version 6.1) without grid lines or ticks

Tried all permutations with styling, but didn’t quite get the grid lines or ticks to disappear. When I inspect the elements, the Highcharts styling looks right, but the grid lines are still visible.

FYI, I tried to follow what is outlined in this documentation but to no avail:

Wondering if anyone has done any styling for Charts?