Add max_height and min_height dimension options.

src/scss/gallery-core.scss

@@ -0,0 +1,51 @@
+:host {
+  width: 100%;
+  height: 100%;
+  display: block;
+  overflow: auto;
+
+  // Hide scrollbar: IE and Edge
+  -ms-overflow-style: none;
+
+  // Hide scrollbar: Firefox
+  scrollbar-width: none;
+
+  --frigate-card-gallery-gap: 3px;
+  --frigate-card-gallery-columns: 4;
+}
+
+.grid {
+  display: grid;
+  grid-template-columns: repeat(var(--frigate-card-gallery-columns), minmax(0, 1fr));
+  grid-auto-rows: min-content;
+  gap: var(--frigate-card-gallery-gap);
+}
+
+// Hide scrollbar for Chrome, Safari and Opera
+:host::-webkit-scrollbar {
+  display: none;
+}
+
+frigate-card-thumbnail {
+  height: 100%;
+  max-height: var(--frigate-card-thumbnail-size);
+}
+frigate-card-thumbnail:not([details]) {
+  width: 100%;
+}
+frigate-card-thumbnail.selected {
+  border: 4px solid var(--accent-color);
+  // Because this is box-sizing: border-box, the border is effectively
+  // 'padding'. To get the curved borders to line up between the thumbnail and
+  // this outer border, we need to add the size of the border to the thumbnail
+  // image border radius.
+  // Related: https://www.30secondsofcode.org/articles/s/css-nested-border-radius
+  border-radius: calc(
+    var(--frigate-card-css-border-radius, var(--ha-card-border-radius, 4px)) + 4px
+  );
+}
+
+frigate-card-progress-indicator.top {
+  // The top loading progress indicator should span the whole width.
+  grid-column: 1/-1;
+}