A hard surface cleaning composition comprising a cleaning system comprising components which render said composition self-adhesive to a hard surface in absence of an adhesive and under a plurality of separate water-based rinses, wherein the water-based rinses have a pH of 6 to 8; and a color-change system; wherein said composition is a gel having a viscosity of from 150 Pa·s to 1000 Pa·s in a temperature range of from 20 °C to 25 °C, and is adapted to progressively dissolve over said plurality of separate water-based rinses of said composition to provide a dissolved cleaning portion; and wherein said color-change system has a pH of 2 to 5 or a pH of 9 to 11 and comprises (a) at least one pH control agent, and (b) at least one color-changing dye - which provides said composition with a first color, and - which is adapted to cause said dissolved cleaning portion to undergo a color change upon each one of said plurality of separate water-based rinses to thereby change said first color of said dissolved cleaning portion to a second color and thereby provide said water-based rinses with said second color, - said first color being different from said second color. a cleaning system comprising components which render said composition self-adhesive to a hard surface in absence of an adhesive and under a plurality of separate water-based rinses, wherein the water-based rinses have a pH of 6 to 8; and a color-change system; wherein said composition is a gel having a viscosity of from 150 Pa·s to 1000 Pa·s in a temperature range of from 20 °C to 25 °C, and is adapted to progressively dissolve over said plurality of separate water-based rinses of said composition to provide a dissolved cleaning portion; and wherein said color-change system has a pH of 2 to 5 or a pH of 9 to 11 and comprises (a) at least one pH control agent, and (b) at least one color-changing dye - which provides said composition with a first color, and - which is adapted to cause said dissolved cleaning portion to undergo a color change upon each one of said plurality of separate water-based rinses to thereby change said first color of said dissolved cleaning portion to a second color and thereby provide said water-based rinses with said second color, - said first color being different from said second color. (a) at least one pH control agent, and (b) at least one color-changing dye - which provides said composition with a first color, and - which is adapted to cause said dissolved cleaning portion to undergo a color change upon each one of said plurality of separate water-based rinses to thereby change said first color of said dissolved cleaning portion to a second color and thereby provide said water-based rinses with said second color, - said first color being different from said second color. - which provides said composition with a first color, and - which is adapted to cause said dissolved cleaning portion to undergo a color change upon each one of said plurality of separate water-based rinses to thereby change said first color of said dissolved cleaning portion to a second color and thereby provide said water-based rinses with said second color, - said first color being different from said second color.