feat: styles for the zoom control buttons

Author: andreishket

vis/stylesheets/modules/_geomap.scss

@@ -68,3 +68,20 @@
     0 1px 5px 0 rgba(0, 0, 0, 0.2);
   border: none;
 }
+
+.leaflet-control-zoom {
+  box-shadow:
+    0 2px 2px 0 rgba(0, 0, 0, 0.14),
+    0 3px 1px -2px rgba(0, 0, 0, 0.12),
+    0 1px 5px 0 rgba(0, 0, 0, 0.2);
+  border: 0;
+
+  & > a > span {
+    color: #818181;
+  }
+
+  & > a[aria-disabled="false"]:hover > span,
+  & > a[aria-disabled="false"] > span {
+    color: #333;
+  }
+}