The ornamental design for a cuplid, as shown and described.
FIG. 1 is a front perspective view of a cup lid showing my new design;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is a front elevational view thereof;
FIG. 4 is a rear elevational view thereof;
FIG. 5 is a left side view thereof;
FIG. 6 is a right side view thereof;
FIG. 7 is a top plan view thereof; and,
FIG. 8 is another front perspective view thereof showing my new design in condition of use.
The broken lines are shown for the purpose of illustrating both parts of the article as well as the boundaries of the claim. None of the broken lines form part of the claimed design.