diff --git a/package-lock.json b/package-lock.json
index e667cbd62e3f4b29b15e846123ac626421b09651..2727c61bb9ac9a81ea533a2b97ce2d52d8b5fc36 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -27,7 +27,11 @@
       }
     },
     "lib": {
-      "name": "@clo/lib"
+      "name": "@clo/lib",
+      "dependencies": {
+        "@clo/lib": "file:.",
+        "@types/node": "^24.0.0"
+      }
     },
     "node_modules/@clo/lib": {
       "resolved": "lib",
@@ -976,7 +980,6 @@
       "resolved": "https://registry.npmjs.org/@types/node/-/node-24.12.0.tgz",
       "integrity": "sha512-GYDxsZi3ChgmckRT9HPU0WEhKLP08ev/Yfcq2AstjrDASOYCSXeyjDsHg4v5t4jOj7cyDX3vmprafKlWIG9MXQ==",
       "license": "MIT",
-      "peer": true,
       "dependencies": {
         "undici-types": "~7.16.0"
       }
diff --git a/src/tags/clover-media.marko b/src/tags/clover-media.marko
new file mode 100644
index 0000000000000000000000000000000000000000..041c200fcd1ada7c95a6c8990d94116ed19c8949
--- /dev/null
+++ b/src/tags/clover-media.marko
@@ -0,0 +1,48 @@
+export interface Input {
+  src: MediaFile | string;
+  alt: string;
+  displayWidthEstimate?: number | string;
+  align?: string;
+}
+
+<const/{ src, alt = "", displayWidthEstimate, align, ...rest } = input />
+<const/file = typeof src === 'object' ? src : MediaFile.getByPath(src) />
+
+<if=!file>
+  <div style={ color: 'red' }>ERROR: No file in database: ${src}</div>
+</><else if=extsVideo.has(file.extension.toLowerCase())>
+  <clover-video noFigure ...{ file } />
+</><else if=file.extension === '.gif'>
+  <img src=`/file${escapeUri(file.path)}` ...rest />
+</><else>
+  <const/base = `/file${escapeUri(file.path)}` />
+  <const/{ width } = UNWRAP(file.parseDimensions()) />
+  <const/targetSizes = transcodeRules.imageSizes.filter((w) => w < width) />
+  <const/sizes =
+    displayWidthEstimate
+      ? typeof displayWidthEstimate === "number"
+        ? `${displayWidthEstimate}px`
+        : displayWidthEstimate
+      : `100vw`
+  />
+  <picture>
+    <for|ext| of=[ "jxl", "avif", "webp" ]>
+      <source
+        type=`image/${ext}`
+        srcset=targetSizes.map((s) => `${base}:/${s}.${ext} ${s}w`)
+        ...{ sizes }
+      />
+    </>
+    <img
+      src=base
+      style=align ? { 'object-position': align, width: '100%', height: '100%' } : undefined
+      ...rest
+    />
+  </picture>
+</>
+
+import * as transcodeRules from "#src/file-viewer/transcode-rules.ts";
+import { extsVideo } from "#src/file-viewer/rules.ts";
+import { MediaFile } from "#src/file-viewer/models/MediaFile.ts";
+import { UNWRAP } from "@clo/lib/assert";
+import { escapeUri } from "#src/file-viewer/format.ts";
diff --git a/src/tags/photo-grid.css b/src/tags/photo-grid.css
index b85c5e8f86952a0c3501dc8ca30d758d89f5fc56..83e1e18d4afcfeabd584256ea0fe8a28cfdba0f0 100644
--- a/src/tags/photo-grid.css
+++ b/src/tags/photo-grid.css
@@ -2,24 +2,23 @@ photo-grid {
   display: grid;
   gap: 11px;
 }
-photo-grid > div {
+photo-grid-item {
+  display: block;
   position: relative;
-  width: 100%;
-  height: 100%;
   border: 2px solid black;
   outline: 4px solid var(--primary, #000);
-}
-photo-grid img {
-  position: absolute;
-  width: 100%;
-  height: 100%;
-  object-fit: cover;
-}
-photo-grid video {
-  position: absolute;
-  top: 0;
-  left: 0;
-  width: 100% !important;
-  height: 100% !important;
-  object-fit: cover;
+  img {
+    position: absolute;
+    width: 100%;
+    height: 100%;
+    object-fit: cover;
+  }
+  video {
+    position: absolute;
+    top: 0;
+    left: 0;
+    width: 100% !important;
+    height: 100% !important;
+    object-fit: cover;
+  }
 }
diff --git a/src/tags/photo-grid.marko b/src/tags/photo-grid.marko
new file mode 100644
index 0000000000000000000000000000000000000000..010f948fc52449f781bd68030ae0f55296f66440
--- /dev/null
+++ b/src/tags/photo-grid.marko
@@ -0,0 +1,107 @@
+import './photo-grid.css';
+
+static const gap = 11;
+
+export interface Input {
+  base?: string;
+  cols: number[]; // weights
+  rows?: number[]; // pixel heights, based on a 768px container
+  style?: Marko.AttrStyle;
+  // images are placed left to right, top to bottom
+  img: Marko.AttrTag<{
+    src: string;
+    w?: number; // column span
+    h?: number; // row span
+    s?: number; // skipped columns before placement
+    small?: unknown;
+    mutedLoop?: boolean;
+    align?: "top" | "center" | "bottom" | (string & {});
+  }>;
+}
+
+static interface Positioned {
+  x: number;
+  y: number;
+  w: number;
+  h: number;
+  align?: string;
+  src: string;
+}
+
+static const alignments = {
+  bottom: "50% 80%",
+  "bottom-end": "50% 100%",
+  top: "50% 30%",
+  "top-end": "50% 0%",
+  left: "30% 50%",
+  "left-end": "0% 50%",
+  right: "80% 50%",
+  "right-end": "100% 50%",
+};
+
+<const/{ base, cols, style } = input />
+<const/rows = input.rows ?? [325] />
+<const/colCount = input.cols.length />
+<const/rowSum = rows.reduce((a, b) => a + b, 0) + gap * (rows.length - 1) />
+
+<const/items = (() => {
+  let occupied: boolean[][] = [];
+  const row = (y: number) => (occupied[y] ??= new Array(colCount).fill(false));
+  const anyCollide = (x: number, y: number, w: number, h: number) => {
+    for (let yy = 0; yy < h; yy++) {
+      const r = row(y + yy);
+      for (let xx = 0; xx < w; xx++) if (r[x + xx]) return true;
+    }
+    return false;
+  };
+
+  let x = 0, y = 0;
+  let result: Positioned[] = [];
+  for (const img of input.img) {
+    const w = img.w ?? 1;
+    const h = img.h ?? 1;
+    const s = img.s ?? 0;
+    if (w > colCount) throw new Error(`image ${img.src} is wider than the grid`);
+
+    x += s;
+    while (x > colCount - w || anyCollide(x, y, w, h)) {
+      x += 1;
+      if (x > colCount - w) x = 0, y += 1;
+    }
+
+    result.push({
+      x,
+      y,
+      w,
+      h,
+      src: base ? base + '/' + img.src : img.src,
+      align: alignments[img.align] ?? img.align,
+    });
+
+    for (let yy = 0; yy < h; yy++) {
+      const r = row(y + yy);
+      for (let xx = 0; xx < w; xx++) r[x + xx] = true;
+    }
+
+    x += w;
+    if (x >= colCount) x = 0, y += 1;
+  }
+  return result;
+})() />
+
+<${'photo-grid'}
+  style={
+    'grid-template-columns': input.cols.map(x => x + 'fr').join(' '),
+    'grid-template-rows': rows.map(x => (100 * x / rowSum).toFixed(1) + '%').join(' '),
+    'aspect-ratio': `768/${rowSum}`,
+    ...style,
+  }
+>
+  <for|{ x, y, w, h, src, align }| of=items>
+    <${'photo-grid-item'} style={
+      'grid-area': `${y + 1} / ${x + 1} / ${1 + y + h} / ${1 + x + w}`,
+    }>
+      <clover-media ...{ src, align } />
+    </>
+  </for>
+</>
diff --git a/src/tags/photo-grid.tsx b/src/tags/photo-grid.tsx
deleted file mode 100644
index 447ef74fb12ee5878b85fff63c3e941080b9ab12..0000000000000000000000000000000000000000
--- a/src/tags/photo-grid.tsx
+++ /dev/null
@@ -1,142 +0,0 @@
-const { isArray } = Array;
-
-export interface PhotoGridProps {
-  style: any;
-  base: string;
-  width: number;
-  widths?: string[];
-  heights?: number[];
-  items: Item[];
-}
-
-type Item = [img: string, options?: ItemOptions];
-
-interface ItemOptions {
-  s?: number;
-  w?: number;
-  h?: number;
-  align?: keyof typeof alignments;
-}
-
-const alignments = {
-  bottom: "50% 80%",
-  "bottom-end": "50% 100%",
-  top: "50% 30%",
-  "top-end": "50% 0%",
-  left: "30% 50%",
-  "left-end": "0% 50%",
-  right: "80% 50%",
-  "right-end": "100% 50%",
-};
-
-const typicalPageWidth = 768;
-
-export function PhotoGrid({
-  style,
-  base,
-  width,
-  widths,
-  heights,
-  items,
-}: PhotoGridProps) {
-  if (!base.endsWith("/")) base += "/";
-  let rows: boolean[][] = [];
-  const row = (y: number) => (rows[y] ??= new Array(width).fill(false));
-  const anyCollide = (x: number, y: number, w: number, h: number) => {
-    for (let yy = 0; yy < h; yy++) {
-      const r = row(y + yy);
-      for (let xx = 0; xx < w; xx++) if (r[x + xx]) return true;
-    }
-    return false;
-  };
-
-  const firstRowHeight = heights?.[0] ?? 325;
-
-  let x = 0;
-  let y = 0;
-  let contents = [];
-  for (const item of items) {
-    const [
-      img,
-      { w = 1, h = 1, align, s } = {},
-    ] = isArray(item) ? item : [item];
-    if (w > width) throw new Error(`Item ${img} too wide (${w} > ${width})`);
-
-    x += s ?? 0;
-
-    while (anyCollide(x, y, w, h)) {
-      x += 1;
-      if (x > width - w) x = 0, y += 1;
-    }
-    for (let yy = 0; yy < h; yy++) {
-      const r = row(y + yy);
-      for (let xx = 0; xx < w; xx++) r[x + xx] = true;
-    }
-
-    const info = fileInfo(base, img);
-    contents.push(
-      <div
-        style={{
-          ...x === 0 && y === 0 &&
-            {
-              "aspect-ratio": ((w / width) * typicalPageWidth) / firstRowHeight,
-            },
-          "grid-area": `${y + 1} / ${x + 1} / ${1 + y + h} / ${1 + x + w}`,
-        }}
-      >
-        <Image
-          {...info}
-          displayWidthEstimate={Math.ceil((w / width) * 736)}
-          style={{
-            "object-position": align
-              ? (alignments as Record<string, string>)[align] ?? align
-              : "50% 50%",
-          }}
-        />
-      </div>,
-    );
-  }
-
-  const height = rows.length;
-  return (
-    <photo-grid
-      style={{
-        ...style,
-        "grid-template-columns": widths
-          ? mapSizes(widths).join(" ")
-          : `repeat(${width}, 1fr)`,
-        "grid-template-rows": heights
-          ? heights.map((h) => (h / firstRowHeight) + "fr")
-            .concat(new Array(height - heights.length).fill("1fr"))
-            .join(" ")
-          : `repeat(${height}, 1fr)`,
-      }}
-    >
-      {contents}
-    </photo-grid>
-  );
-}
-
-function fileInfo(base: string, img: string) {
-  const filePath = path.join(base, img);
-  const file = MediaFile.getByPath(filePath);
-  const dimensions = file?.parseDimensions();
-  if (!dimensions) {
-    throw new Error(`File does not exist or has no dimensions: ${filePath}`);
-  }
-  const alt = path.basename(img, path.extname(img));
-  return { src: file, alt, width: dimensions.width, height: dimensions.height };
-}
-
-function mapSizes(sizes: Array<string | number>) {
-  return sizes.map(mapSize);
-}
-function mapSize(size: string | number) {
-  return typeof size === "number" ? size + "px" : size;
-}
-
-import "./photo-grid.css";
-import { MediaFile } from "#src/file-viewer/models/MediaFile.ts";
-import Image from "./image.tsx";
-import * as path from "node:path";
-import { ASSERT } from "@clo/lib/assert";