Step 1
Using the Ellipse Tool (L), draw a circle covering the lower half of the hexagons. Apply a Linear Gradient going from R=255 G=214 B=82 at 100% to 0% Opacity and angled at 90°. Select the inner hexagon and the gradient circle. Using the Shape Builder Tool (Shift-M), select the portion of the gradient circle that does not overlap the inner hexagon. Deselect and delete for a clean half circle over the honeycomb.