From here you can apply a different layout ... border color, and much more. For additional formatting options to spice up your bubble chart in Excel, you can make use of the format buttons.

Among its many features, Microsoft Excel enables ... A pie chart divides a circle into slices to represent a data series. The chart depicts each pie slice in a different color for easy recognition ...

Making a square bubble chart in Microsoft Office Excel is possible if you slightly modify the chart. A bubble chart is a type of scatter chart in which your data points are shown as bubbles.