electric blue 
noun [mass noun]
A steely or brilliant light blue: the pot is decorated with circles of electric blue [as modifier]: an electric-blue sports car...
- Out of the nasturtiums rose three wonderful electric-blue necks, each topped by an imperious Jurassic face: peacocks!
- Beyond your balcony, is the sparkling water, where in the early morning, large manta rays bask in the sunshine and electric-blue fish dart in frenzy.
- Though kayakers flock to the island's electric-blue waters, you can always find an empty cove to call your own.