[Glitch] Improve announcements design

Port 48c55b6392 to glitch-soc

Signed-off-by: Thibaut Girka <thib@sitedethib.com>

app/javascript/flavours/glitch/styles/components/announcements.scss

@@ -37,7 +37,7 @@
 }
 
 .announcements {
-  background: lighten($ui-base-color, 4%);
+  background: lighten($ui-base-color, 8%);
   border-top: 1px solid $ui-base-color;
   font-size: 13px;
   display: flex;
@@ -78,12 +78,6 @@
       font-weight: 500;
       margin-bottom: 10px;
     }
-
-    &__dismiss-icon {
-      position: absolute;
-      top: 12px;
-      right: 12px;
-    }
   }
 
   &__pagination {