Remove duplicate opacity declaration in thumbnail styles

Author: Pretty Taruvinga

challenges/challenge-weather-app/assets/styles.css

@@ -113,7 +113,6 @@
   animation: 0.25s forwards fade-in;
 
   display: block;
-  opacity: 0;
   object-fit: cover;
 
   flex: 0 0 auto;
@@ -125,7 +124,6 @@
   background: rgba(0, 0, 0, 0.5);
 }
 
-
 /* Credits
 ------------------------------------------------------------------------------*/
 .info {