Update colors for table of contents (facebook#4412)

Author: clicktodev

website/src/css/customTheme.scss

@@ -1100,11 +1100,11 @@ div[class^="tableOfContents"] {
     margin-left: -16px;
     padding-left: 12px;
     color: var(--ifm-font-color-base);
-    border-left: 4px solid var(--brand);
+    border-left: 4px solid var(--ifm-link-color);
 
     code {
-      font-weight: 600;
       color: var(--ifm-font-color-base);
+      font-weight: 700;
       white-space: nowrap;
     }
 
@@ -1118,6 +1118,22 @@ div[class^="tableOfContents"] {
   }
 }
 
+html[data-theme="dark"] {
+  .table-of-contents {
+    .table-of-contents__link--active {
+      color: var(--ifm-link-color);
+
+      &:hover {
+        color: var(--ifm-link-color);
+
+        code {
+          color: var(--ifm-link-color);
+        }
+      }
+    }
+  }
+}
+
 html[data-theme="dark"] div[class^="tableOfContents"] {
   @extend %scrollbar-style-dark;
 }