fix (bottom separator): bring bottom separator to back of content (#3190

)

* fix bottom separator

* fix glitch in editor

* update z-index

src/block-components/separator/style.scss

@@ -7,7 +7,13 @@
 		}
 
 		.stk-separator ~ *:not(.stk-separator, .stk-video-background) {
-			z-index: 5;
+			z-index: 3;
+			position: relative;
+		}
+	}
+	&.stk-has-bottom-separator:not(.stk-has-top-separator) {
+		> *:not(.stk-separator, .stk-video-background) {
+			z-index: 3;
 			position: relative;
 		}
 	}