Added styles extracted from reForis.

src/bootstrap/Modal.css

+@keyframes modalFade {
+    from {
+        opacity: 0;
+    }
+    to {
+        opacity: 1;
+    }
+}
+
+.modal.show {
+    display: block;
+    animation-name: modalFade;
+    animation-duration: .3s;
+    background: rgba(0, 0, 0, 0.2);
+}