Animation pop-up window

Signed-off-by: Valentin Popov <info@valentineus.link>

_scss/_animate.scss

@@ -0,0 +1,19 @@
+@import 'utilities/keyframes';
+
+@include keyframes(fadeIn) {
+  from {
+    opacity: 0;
+  }
+  to {
+    opacity: 1;
+  }
+}
+
+@include keyframes(fadeOut) {
+  from {
+    opacity: 1;
+  }
+  to {
+    opacity: 0;
+  }
+}