Update for Org Chart 4.
It is possible to customize styles for a certain level of the chart. For that, it is necessary to enable displaying the level number:
Then add the code snippet below on the Custom JavaScript step (note: the code is for the Modern skin, for others you may need to modify the jQuery selector):
api.onBoxRendered((box, itemData) => {
//Box rendered event
//Check if the level number of the current box is equal to 2 and...
if (itemData.pochContext.boxLevelNumber == 2) {
//...find the element by a class and assign a custom one with jQuery
$(box.elem).find(".poch-group-item__card").addClass("level-2");
}
});
On the Custom CSS step, set custom styles for the custom class assigned above.
.level-2 {
background-color: green !important;
}
The result if the following:



