show photo in an overlay

frontend/src/Photos/Overview.scss

@@ -1,5 +1,32 @@
 @import "~@blueprintjs/core/lib/scss/variables";
 
+#photoOverlayContainer {
+    width: 100%;
+    height: 100%;
+    display: flex;
+    align-items: center;
+    justify-content: center;
+    transition: 0.3s;
+}
+
+.bp3-overlay-enter {
+    opacity: 0;
+}
+
+.bp3-overlay-enter-active {
+    opacity: 1;
+}
+
+
+.bp3-overlay-exit {
+    opacity: 1;
+}
+
+.bp3-overlay-exit-active {
+    opacity: 0;
+}
+
+
 #overview {
     display: flex;
     flex-direction: column;