A first selection of mesh line segments of a mesh layer are of a first width and a second selection of mesh line segments of the mesh layer are of a second width, wherein the second width is greater than the first width. The second selection of mesh line segments of the second width are positioned in parallel to a selection of signal lines in a signal layer that are likely to introduce crosstalk, wherein the widening of the mesh line segments shadowing the selection of signal lines increases the likelihood that the return current associated with the signal will flow in the wider mesh line segment, thereby increasing the likelihood of containing the electromagnetic fields associated with the signal such that crosstalk to other signals is reduced or contained.