reset text color of .hot-table-container

src/client/styles/scss/theme/_apply-colors.scss

@@ -115,6 +115,13 @@ pre:not(.hljs):not(.CodeMirror-line) {
   }
 }
 
+//
+//== Apply to Handsontable
+//
+.hot-table-container {
+  color: initial;
+}
+
 //
 //== Apply to GROWI Elements
 //