Preserve chronological order in gapless gallery rows

_sass/_layout.scss

@@ -227,16 +227,22 @@ hr {
 }
 
 .art .post-list {
-  column-count: 2;
-  column-gap: $spacing-unit;
+  .gallery-row {
+    display: flex;
+    gap: $spacing-unit;
+    align-items: flex-start;
+    list-style: none;
+    margin: 0 0 $spacing-unit;
 
-  > li {
-    display: inline-block;
-    width: 100%;
-    margin-top: 0;
-    margin-bottom: $spacing-unit;
-    break-inside: avoid;
-    -webkit-column-break-inside: avoid;
+    > li {
+      flex: var(--photo-ratio) 1 0;
+      min-width: 0;
+      margin: 0;
+    }
+
+    > li:only-child {
+      flex: 0 0 calc((100% - #{$spacing-unit}) / 2);
+    }
   }
 
   .post-content > p:last-child {
@@ -249,11 +255,17 @@ hr {
     height: auto;
     margin: 0;
     // Reserve space before lazy images load, then use their natural proportions.
-    aspect-ratio: auto 3 / 2;
+    aspect-ratio: auto var(--photo-ratio, 3 / 2);
   }
 
   @include media-query($on-palm) {
-    column-count: 1;
+    .gallery-row {
+      display: block;
+
+      > li {
+        margin-bottom: $spacing-unit;
+      }
+    }
   }
 }