Fix resizer highlight and scroll bar style

app/index.html

@@ -39,7 +39,8 @@
         }
 
         ::-webkit-scrollbar-track {
-          -webkit-box-shadow: inset 0 0 6px rgba(30,30,30,0.3);
+          -webkit-box-shadow: inset 0 0 6px rgba(60,60,60,0.5);
+          background-color: rgba(140,140,140,0.1);
         }
 
         ::-webkit-scrollbar-thumb {
@@ -74,21 +75,23 @@
         }
 
         .Resizer.horizontal:hover {
-            border-top: 5px solid rgba(0, 0, 0, 0.5);
-            border-bottom: 5px solid rgba(0, 0, 0, 0.5);
+            border-top: 5px solid rgba(120, 120, 120, 0.5);
+            border-bottom: 5px solid rgba(120, 120, 120, 0.5);
         }
 
         .Resizer.vertical {
-            width: 11px;
-            margin: 0 -5px;
-            border-left: 5px solid rgba(255, 255, 255, 0);
-            border-right: 5px solid rgba(255, 255, 255, 0);
+            /* width: 11px;
+            margin: 0 -5px; */
+            width: 2px;
+            margin: 0px -8px 0px 0px;
+            border-left: 4px solid rgba(128, 128, 128, 0);
+            border-right: 4px solid rgba(128, 128, 128, 0);
             cursor: col-resize;
         }
 
         .Resizer.vertical:hover {
-            border-left: 5px solid rgba(255, 255, 255, 0.5);
-            border-right: 5px solid rgba(255, 255, 255, 0.5);
+            border-left: 4px solid rgba(130, 130, 130, 1);
+            border-right: 4px solid rgba(140, 140, 140, 1);
         }
         .Resizer.disabled {
           cursor: not-allowed;

app/src/components/Layout/ContentView.tsx

@@ -12,7 +12,6 @@ export default function ContentView(props: {heightProperty: any, paneDefaults: a
       split="vertical"
       minSize={250}
       defaultSize={500}
-      resizerStyle={{ width: '2px', margin: '0 -10px 0 0px' }}
       allowResize={true}
       style={{ position: 'relative' }}
       pane1Style={{ overflow: 'hidden' }}

app/src/components/Sidebar/CodeDiff.tsx

@@ -5,7 +5,6 @@ import { CodeBlockColors, CodeBlockColorsBraceMonokai } from './CodeBlockColors'
 import { selectTextWithCtrlA } from '../../utils/handleTextSelectWithCtrlA'
 import { Theme, withStyles } from '@material-ui/core'
 import 'prismjs/components/prism-json'
-import 'prismjs/themes/prism-tomorrow.css'
 
 interface Props {
   previous: string