The ornamental design for a mirror, as shown and described.
FIG. 1 is a front perspective view of a mirror showing our new design;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a rear elevation view thereof;
FIG. 4 is a left-side elevation view thereof;
FIG. 5 is a right-side elevation view thereof;
FIG. 6 is a top plan view thereof;
FIG. 7 is a bottom plan view thereof; and,
FIG. 8 is an enlarged detail view of the encircled portion of FIG. 2.
The broken lines in the drawings are shown for the purpose of illustrating enlargement view designations and parts of the article that form no part of the claim.
The oblique shade lines in the figures represent a mirrored surface.