UI - Visual Selector graphics should be centred

changedetectionio/static/styles/scss/parts/_visualselector.scss

@@ -1,6 +1,8 @@
 
 #selector-wrapper {
   height: 100%;
+  text-align: center;
+  
   max-height: 70vh;
   overflow-y: scroll;
   position: relative;

changedetectionio/static/styles/styles.css

@@ -1065,6 +1065,7 @@ ul {
 
 #selector-wrapper {
   height: 100%;
+  text-align: center;
   max-height: 70vh;
   overflow-y: scroll;
   position: relative; }