add login/sign-up page with dark/light mode

node_modules/eslint-plugin-jsx-a11y/__mocks__/JSXExpressionContainerMock.js

@@ -0,0 +1,15 @@
+/**
+ * @flow
+ */
+
+export type JSXExpressionContainerMockType = {
+  type: 'JSXExpressionContainer',
+  expression: mixed,
+}
+
+export default function JSXExpressionContainerMock(exp: mixed): JSXExpressionContainerMockType {
+  return {
+    type: 'JSXExpressionContainer',
+    expression: exp,
+  };
+}