Fix small-width media indentation in status carousels

Center-ize it, add a background color

src/components/status.css

@@ -751,6 +751,11 @@
 
   &:not(.media-figure-multiple .media-container) {
     margin-bottom: -16px;
+
+    &.media-eq1 {
+      text-align: center;
+      background-color: var(--img-bg-color);
+    }
   }
 
   .media {

src/index.css

@@ -83,7 +83,7 @@
   --private-note-bg-color: color-mix(in srgb, yellow 20%, var(--bg-color));
   --private-note-border-color: rgba(0, 0, 0, 0.2);
 
-  /* Video colors won't change based on color scheme */
+  /* Media colors won't change based on color scheme */
   --media-fg-color: #f0f2f5;
   --media-bg-color: #242526;
   --media-outline-color: color-mix(in lch, var(--media-fg-color), transparent);