Reduce flicker when moving between blocks with keyboard

resources/css/common.css

@@ -878,7 +878,7 @@ h1.title {
 
 .block-highlight,
 .content .selected {
-  transition: background-color 0.15s;
+  transition: background-color 0.2s cubic-bezier(0, 1, 0, 1);
   background-color: var(--ls-block-highlight-color);
   padding: -1px;
 }

src/main/frontend/components/block.css

@@ -335,6 +335,7 @@
   min-height: 24px;
   padding: 2px 0;
   border-bottom: 1px solid transparent;
+  transition: background-color 0.3s cubic-bezier(0.16, 1, 0.3, 1);
 
   &.selected {
     border-bottom-color: var(--ls-primary-background-color);