Issue #967: white is a very light gray; less confusing than lightgray

src/Tm3DStandaloneApp/tmdet-viewer/TmViewerStandalone.ts

@@ -109,7 +109,7 @@ export class TmViewerStandalone extends Viewer {
                             `(sel.atom.atom-groups :chain-test (set.has (set ${chainList}) atom.label_asym_id))`,
                             'mol-script'
                         ),
-                        color:  hexRgb !== false ? Color.fromHexString(hexRgb) : ColorNames.grey,
+                        color:  hexRgb !== false ? Color.fromHexString(hexRgb) : ColorNames.white,
                         clear: clear
                     }
                 ]