The design consists of the visual features of the LIGHT FIXTURE shown in solid lines in the drawings, whether those features are one of shape, configuration, ornament or pattern or are a combination of any of these features. The portions of the LIGHT FIXTURE shown in stippled lines do not form part of the design. The portions shown with break lines are of variable length and all variations occur in equal proportions. Drawings of the design are included, in which: FIG. 1A is a front-right, top perspective view of a LIGHT FIXTURE, according to a first variant; FIG. 1B is a front side view of the LIGHT FIXTURE, according to the first variant; FIG. 1C is a left side view of the LIGHT FIXTURE, according to the first variant; FIG. 1D is a right side view of the LIGHT FIXTURE, according to the first variant; FIG. 1E is a top view of the LIGHT FIXTURE, according to the first variant; FIG. 1F is a bottom view of the LIGHT FIXTURE, according to the first variant; FIG. 2A is a front-right, top perspective view of a LIGHT FIXTURE, according to a second variant; FIG. 2B is a front side view of the LIGHT FIXTURE, according to the second variant; FIG. 2C is a left side view of the LIGHT FIXTURE, according to the second variant; FIG. 2D is a right side view of the LIGHT FIXTURE, according to the second variant; FIG. 2E is a top view of the LIGHT FIXTURE, according to the second variant; FIG. 2F is a bottom view of the LIGHT FIXTURE, according to the second variant; FIG. 3A is a front, bottom perspective view of a LIGHT FIXTURE, according to a third variant; FIG. 3B is a front side view of the LIGHT FIXTURE, according to the third variant; FIG. 3C is a left side view of the LIGHT FIXTURE, according to the third variant; FIG. 3D is a right side view of the LIGHT FIXTURE, according to the third variant; FIG. 3E is a top view of the LIGHT FIXTURE, according to the third variant; FIG. 3F is a bottom view of the LIGHT FIXTURE, according to the third variant; FIG. 4A is a front, bottom perspective view of a LIGHT FIXTURE, according to a fourth variant; FIG. 4B is a front side view of the LIGHT FIXTURE, according to the fourth variant; FIG. 4C is a left side view of the LIGHT FIXTURE, according to the fourth variant; FIG. 4D is a right side view of the LIGHT FIXTURE, according to the fourth variant; FIG. 4E is a top view of the LIGHT FIXTURE, according to the fourth variant; FIG. 4F is a bottom view of the LIGHT FIXTURE, according to the fourth variant; FIG. 5A is a front, bottom perspective view of a LIGHT FIXTURE, according to a fifth variant; FIG. 5B is a front side view of the LIGHT FIXTURE, according to the fifth variant; FIG. 5C is a left side view of the LIGHT FIXTURE, according to the fifth variant; FIG. 5D is a right side view of the LIGHT FIXTURE, according to the fifth variant; FIG. 5E is a top view of the LIGHT FIXTURE, according to the fifth variant; FIG. 5F is a bottom view of the LIGHT FIXTURE, according to the fifth variant; FIG. 6A is a front, bottom perspective view of a LIGHT FIXTURE, according to a sixth variant; FIG. 6B is a front side view of the LIGHT FIXTURE, according to the sixth variant; FIG. 6C is a left side view of the LIGHT FIXTURE, according to the sixth variant; FIG. 6D is a right side view of the LIGHT FIXTURE, according to the sixth variant; FIG. 6E is a top view of the LIGHT FIXTURE, according to the sixth variant; FIG. 6F is a bottom view of the LIGHT FIXTURE, according to the sixth variant; FIG. 7A is a front, bottom perspective view of a LIGHT FIXTURE, according to a seventh variant; FIG. 7B is a front side view of the LIGHT FIXTURE, according to the seventh variant; FIG. 7C is a left side view of the LIGHT FIXTURE, according to the seventh variant; FIG. 7D is a right side view of the LIGHT FIXTURE, according to the seventh variant; FIG. 7E is a top view of the LIGHT FIXTURE, according to the seventh variant; FIG. 7F is a bottom view of the LIGHT FIXTURE, according to the seventh variant; FIG. 8A is a front, bottom perspective view of a LIGHT FIXTURE, according to an eighth variant; FIG. 8B is a front side view of the LIGHT FIXTURE, according to the eighth variant; FIG. 8C is a left side view of the LIGHT FIXTURE, according to the eighth variant; FIG. 8D is a right side view of the LIGHT FIXTURE, according to the eighth variant; FIG. 8E is a top view of the LIGHT FIXTURE, according to the eighth variant; and FIG. 8F is a bottom view of the LIGHT FIXTURE, according to the eighth variant.