fadelessly

fade·less

 (fād′lĭs)
adj.
Not fading or not subject to fading: fadeless fabric.

fade′less·ly adv.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

fadelessly

(ˈfeɪdləslɪ)
adv
in a fadeless manner
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014