We claim the ornamental design for a countertop, as shown and described.
FIG. 1 is a perspective view of a countertop showing our new design;
FIG. 2 is a top plan view thereof;
FIG. 3 is a bottom plan view thereof;
FIG. 4 is a front elevation thereof;
FIG. 5 is a rear elevation view thereof;
FIG. 6 is a right side elevation view thereof;
FIG. 7 is a left side elevation view thereof; and,
FIG. 8 is another perspective view thereof shown in the environment of a cabinet.
The broken lines of the cabinets, faucets, and soap dispensers of FIG. 8 are directed to environment and form no part of the claimed design. All other broken lines are directed to unclaimed features and form no part of the claimed design.