Sky blue

Sky blue was a light shade of blue called for the sky

The Eleventh Doctor wore a sky blue shirt during his travels with Clara Oswald (TV: The Bells of Saint John, The Day of the Doctor, et alt.) leading up to his death and regeneration into the Twelfth Doctor (who consequently spent his first hours in that same shirt). (TV: The Time of the Doctor) The Tenth Doctor had previously worn a sky blue shirt during his encounter with the Wire. (TV: The Idiot's Lantern)

Diane Holmes also wore a sky blue shirt, with her sleeves rolled up, when adapting to the 21st century. (TV: Out of Time)

Sarah Jane Smith sometimes wore a sky blue shirt. (TV: The Day of the Clown, Enemy of the Bane)

Tthe General's uniform wore a sky blue uniform during the original Gallifreyan Civil War, complemented by golden epaulettes. (PROSE: Warmonger)