redo main/register page

public/resources/animate.css-main/source/attention_seekers/flash.css

@@ -0,0 +1,16 @@
+@keyframes flash {
+  from,
+  50%,
+  to {
+    opacity: 1;
+  }
+
+  25%,
+  75% {
+    opacity: 0;
+  }
+}
+
+.flash {
+  animation-name: flash;
+}