:art: more z fighting fixes

vue-theme/src/components/hero.vue

             .hero--image--overlay.w-max.f-col
                 h2.t-up.t-cntr(v-if="heroText") {{ heroText }}
             img.w-max(:src="getThumbnailFromYt(showHero)" alt="hero alt image")
-            button(v-if="showPlaybutton" @click="isPlaying = true")
+            button(v-if="showPlaybutton" @click="isPlaying = true").z-top
 
     .hero--image.w-max(v-else-if="heroType === 'image'")
         .hero--image--overlay.w-max.f-col
             &:after 
                 content: ""
                 position: absolute
-                top: 20%
-                left: 35%
+                top: 30%
+                left: 40%
                 border-style: solid
                 border-width: 1em 0 1em 1.6em
                 border-color: transparent transparent transparent white

vue-theme/src/components/navigation/navigation.vue

     /* background-color: lightblue */
     background-color: $cia_grey
     word-wrap: break-word
-    z-index: 10000
+    z-index: 10002
     .menu, .mobile-menu
         /* padding: $ms-0 0 */
         a