[REF]: Improve black gradient layer for upload layer

src/files-ui/components/file-card/FileCard.scss

 @import url(https://fonts.googleapis.com/css?family=Poppins:300,400,500,600,700,900);
+
 .files-ui-file-card-main-container {
   border-radius: 8px;
   //overflow: hidden;
@@ -130,15 +131,11 @@
       //background-color: rgba(0, 0, 0, 0.5);
       background: linear-gradient(
         to right,
-        rgba(0, 0, 0, 0.25),
-        rgba(0, 0, 0, 0.3),
-        rgba(0, 0, 0, 0.5),
-        rgba(0, 0, 0, 0.75),
-        rgba(0, 0, 0, 0.85),
-        rgba(0, 0, 0, 0.85),
-        rgba(0, 0, 0, 0.85),
-        rgba(0, 0, 0, 0.85),
-        rgba(0, 0, 0, 0.85)
+        rgba(0, 0, 0, 0.2),
+        rgba(0, 0, 0, 0.35),
+        rgba(0, 0, 0, 0.625),
+        rgba(0, 0, 0, 0.9),
+        rgba(0, 0, 0, 0.9)
       );
       color: rgba(255, 255, 255, 0.8);
       font-weight: 500;
@@ -155,15 +152,16 @@
       //background-color: rgba(0, 0, 0, 0.5);
       background: linear-gradient(
         to right,
-
+        rgba(0, 0, 0, 0.2),
         rgba(0, 0, 0, 0.3),
-        rgba(0, 0, 0, 0.5),
+        rgba(0, 0, 0, 0.4),
         rgba(0, 0, 0, 0.75),
         rgba(0, 0, 0, 0.9),
         rgba(0, 0, 0, 0.9),
         rgba(0, 0, 0, 0.9),
         rgba(0, 0, 0, 0.9),
         rgba(0, 0, 0, 0.9),
+        rgba(0, 0, 0, 0.9),
         rgba(0, 0, 0, 0.9)
       );
       color: rgba(255, 255, 255, 0.8);

src/files-ui/components/file-mosaic/components/FileMosaicUploadLayer/FileMosaicUploadLayer.scss

 .files-ui-file-mosaic-upload-layer {
   width: 100%;
   height: 100%;
-  background-color: rgba(0, 0, 0, 0.5);
+  background-color: rgba(0, 0, 0, 0.65);
   color: rgba(255, 255, 255, 0.8);
   font-weight: 500;
   font-size: 1em;