style(front): subtle border for cards in dark-mode

front/src/components/audio/ChannelCard.vue

@@ -49,6 +49,7 @@ const updatedAgo = computed(() => moment(props.object.artist?.modification_date)
     :tags="object.artist?.tags ?? []"
     class="artist-card"
     :to="{name: 'channels.detail', params: {id: urlId}}"
+    solid
     small
   >
     <template #topright>

front/src/style/colors.scss

@@ -533,7 +533,7 @@
   .solid, .alert>.actions>button, button:not(:is(.ghost,.outline,.tabs-item)) {
     color: var(--color);
     background-color:var(--background-color);
-    border: 1px solid var(--background-color);
+    border: 1px solid var(--fw-gray-850);
 
     &.interactive:not(:has(.interactive:hover)) {
       &:hover {