Dark theme: improve keyboard shortcuts dialog styles

Fixed: twpowertools:72
Change-Id: Ib657c137ef564454444ffb22753f994b69729a6d
diff --git a/src/static/css/ccdarktheme.css b/src/static/css/ccdarktheme.css
index a88fd7b..0f45b20 100644
--- a/src/static/css/ccdarktheme.css
+++ b/src/static/css/ccdarktheme.css
@@ -746,10 +746,27 @@
 }
 
 /* Keyboard shortcuts dialog */
-material-dialog .main.with-scroll-strokes table td {
+material-dialog .main.with-scroll-strokes table th {
   color: var(--TWPT-primary-text)!important;
 }
 
+material-dialog .main.with-scroll-strokes table td {
+  color: var(--TWPT-primary-text-alt)!important;
+}
+
+material-dialog .main.with-scroll-strokes table tr,
+    material-dialog .main.with-scroll-strokes .shortcut {
+  border-color: var(--TWPT-card-border)!important;
+}
+
+material-dialog .main.with-scroll-strokes.bottom-scroll-stroke {
+  border-bottom-color: var(--TWPT-card-border)!important;
+}
+
+material-dialog .main.with-scroll-strokes.top-scroll-stroke {
+  border-top-color: var(--TWPT-card-border)!important;
+}
+
 /* Rich text editor */
 ec-editor-command material-button,
     ec-formatting-popup material-button {