diff --git a/bun.lockb b/bun.lockb
index 8acbc1a..bab2499 100755
Binary files a/bun.lockb and b/bun.lockb differ
diff --git a/package.json b/package.json
index 70973f6..6e1fdb9 100644
--- a/package.json
+++ b/package.json
@@ -17,16 +17,16 @@
     "@suid/vite-plugin": "^0.3.1",
     "@types/hammerjs": "^2.0.46",
     "@vite-pwa/assets-generator": "^0.2.6",
-    "postcss": "^8.4.49",
+    "postcss": "^8.4.47",
     "prettier": "^3.3.3",
     "typescript": "^5.6.3",
-    "vite": "^5.4.11",
+    "vite": "^5.4.10",
     "vite-plugin-package-version": "^1.1.0",
     "vite-plugin-pwa": "^0.20.5",
     "vite-plugin-solid": "^2.10.2",
     "vite-plugin-solid-styled": "^0.11.1",
     "workbox-build": "^7.3.0",
-    "wrangler": "^3.86.1"
+    "wrangler": "^3.84.1"
   },
   "dependencies": {
     "@formatjs/intl-localematcher": "^0.5.7",
@@ -38,7 +38,7 @@
     "@solid-primitives/map": "^0.4.13",
     "@solid-primitives/page-visibility": "^2.0.17",
     "@solid-primitives/resize-observer": "^2.0.26",
-    "@solidjs/router": "^0.15.1",
+    "@solidjs/router": "^0.14.10",
     "@suid/icons-material": "^0.8.1",
     "@suid/material": "^0.18.0",
     "blurhash": "^2.0.5",
diff --git a/src/timelines/MediaAttachmentGrid.css b/src/timelines/MediaAttachmentGrid.css
deleted file mode 100644
index 6b659c4..0000000
--- a/src/timelines/MediaAttachmentGrid.css
+++ /dev/null
@@ -1,27 +0,0 @@
-.MediaAttachmentGrid {
-  /* Note: MeidaAttachmentGrid has hard-coded layout calcalation */
-  margin-top: 1em;
-  margin-left: calc(var(--card-pad, 0) + var(--toot-avatar-size, 0) + 8px);
-  margin-right: var(--card-pad, 0);
-  gap: 4px;
-
-  > :where(img, video) {
-    max-height: 35vh;
-    min-height: 40px;
-    min-width: 40px;
-    object-fit: contain;
-    max-width: 100%;
-    background-color: var(--tutu-color-surface-d);
-    border-radius: 2px;
-    border: 1px solid var(--tutu-color-surface-d);
-    transition: outline-width 60ms var(--tutu-anim-curve-std), border-color 60ms var(--tutu-anim-curve-std);
-    contain: strict;
-    content-visibility: auto;
-
-    &:hover,
-    &:focus-visible {
-      outline: 8px solid var(--media-color-accent, var(--tutu-color-surface-d));
-      border-color: var(--media-color-accent, var(--tutu-color-surface-d));
-    }
-  }
-}
\ No newline at end of file
diff --git a/src/timelines/MediaAttachmentGrid.tsx b/src/timelines/MediaAttachmentGrid.tsx
index 2b9db57..3f7147c 100644
--- a/src/timelines/MediaAttachmentGrid.tsx
+++ b/src/timelines/MediaAttachmentGrid.tsx
@@ -10,6 +10,8 @@ import {
   createSignal,
   onCleanup,
 } from "solid-js";
+import { css } from "solid-styled";
+import tootStyle from "./toot.module.css";
 import MediaViewer from "./MediaViewer";
 import { render } from "solid-js/web";
 import {
@@ -19,8 +21,6 @@ import {
 import { useStore } from "@nanostores/solid";
 import { $settings } from "../settings/stores";
 import { averageColorHex } from "../platform/blurhash";
-import "./MediaAttachmentGrid.css";
-import cardStyle from "../material/cards.module.css";
 
 type ElementSize = { width: number; height: number };
 
@@ -114,6 +114,13 @@ const MediaAttachmentGrid: Component<{
       itemMaxSize(),
     );
 
+    // I don't know why mastodon does not return this
+    // and the condition for it to return this.
+    // Anyway, It is useless now.
+    // My hope is the FastAverageColor, but
+    // we may need better tool to manage the performance impact
+    // before using this. See #37.
+    // TODO: use fast average color to extract accent color
     const accentColor =
       item.meta?.colors?.accent ??
       (item.blurhash ? averageColorHex(item.blurhash) : undefined);
@@ -127,11 +134,16 @@ const MediaAttachmentGrid: Component<{
       accentColor ? { "--media-color-accent": accentColor } : {},
     );
   };
+
+  css`
+    .attachments {
+      column-count: ${columnCount().toString()};
+    }
+  `;
   return (
     <section
       ref={setRootRef}
-      class={`MediaAttachmentGrid ${cardStyle.cardNoPad}`}
-      style={{ "column-count": columnCount() }}
+      class={[tootStyle.tootAttachmentGrp, "attachments"].join(" ")}
       onClick={(e) => {
         if (e.target !== e.currentTarget) {
           e.stopImmediatePropagation();
diff --git a/src/timelines/RegularToot.tsx b/src/timelines/RegularToot.tsx
index f72e4fc..ffcae6a 100644
--- a/src/timelines/RegularToot.tsx
+++ b/src/timelines/RegularToot.tsx
@@ -5,11 +5,13 @@ import {
   type JSX,
   Show,
   createRenderEffect,
+  createEffect,
+  createMemo,
 } from "solid-js";
 import tootStyle from "./toot.module.css";
 import { formatRelative } from "date-fns";
 import Img from "../material/Img.js";
-import { Body2 } from "../material/typography.js";
+import { Body1, Body2, Title } from "../material/typography.js";
 import { css } from "solid-styled";
 import {
   BookmarkAddOutlined,
@@ -28,12 +30,13 @@ import { Divider } from "@suid/material";
 import cardStyle from "../material/cards.module.css";
 import Button from "../material/Button.js";
 import MediaAttachmentGrid from "./MediaAttachmentGrid.js";
+import Color from "colorjs.io";
 import { useDateFnLocale } from "../platform/i18n";
 import { canShare, share } from "../platform/share";
 import { makeAcctText, useDefaultSession } from "../masto/clients";
 import TootContent from "./toot-components/TootContent";
 import BoostIcon from "./toot-components/BoostIcon";
-import PreviewCard from "./toot-components/PreviewCard";
+import { averageColorHex } from "../platform/blurhash";
 
 type TootActionGroupProps<T extends mastodon.v1.Status> = {
   onRetoot?: (value: T) => void;
@@ -183,6 +186,95 @@ function TootAuthorGroup(
   );
 }
 
+export function TootPreviewCard(props: {
+  src: mastodon.v1.PreviewCard;
+  alwaysCompact?: boolean;
+}) {
+  let root: HTMLAnchorElement;
+
+  createEffect(() => {
+    if (props.alwaysCompact) {
+      root.classList.add(tootStyle.compact);
+      return;
+    }
+    if (!props.src.width) return;
+    const width = root.getBoundingClientRect().width;
+    if (width > props.src.width) {
+      root.classList.add(tootStyle.compact);
+    } else {
+      root.classList.remove(tootStyle.compact);
+    }
+  });
+
+  const imgAverageColor = createMemo(() => {
+    if (!props.src.image) return;
+    return new Color(averageColorHex(props.src.blurhash));
+  });
+
+  const prefersWhiteText = createMemo(() => {
+    const oc = imgAverageColor();
+    if (!oc) return;
+    const colorWhite = new Color("white");
+
+    return colorWhite.luminance / oc.luminance > 3.5;
+  });
+
+  const focusSurfaceColor = createMemo(() => {
+    const oc = imgAverageColor();
+    if (!oc) return;
+    if (prefersWhiteText()) {
+      return new Color(oc).darken(0.2);
+    } else {
+      return new Color(oc).lighten(0.2);
+    }
+  });
+
+  const textColorName = createMemo(() => {
+    const useWhiteText = prefersWhiteText();
+    if (typeof useWhiteText === "undefined") {
+      return;
+    }
+    return useWhiteText ? "white" : "black";
+  });
+
+  const secondaryTextColor = createMemo(() => {
+    const tcn = textColorName();
+    if (!tcn) return;
+    const tc = new Color(tcn);
+    tc.alpha = 0.75;
+    return tc;
+  });
+
+  return (
+    <a
+      ref={root!}
+      class={tootStyle.previewCard}
+      href={props.src.url}
+      target="_blank"
+      referrerPolicy="unsafe-url"
+      style={{
+        "--tutu-color-surface": imgAverageColor()?.toString(),
+        "--tutu-color-surface-d": focusSurfaceColor()?.toString(),
+        "--tutu-color-on-surface": textColorName(),
+        "--tutu-color-secondary-text-on-surface":
+          secondaryTextColor()?.toString(),
+      }}
+    >
+      <Show when={props.src.image}>
+        <img
+          crossOrigin="anonymous"
+          src={props.src.image!}
+          width={props.src.width || undefined}
+          height={props.src.height || undefined}
+          loading="lazy"
+        />
+      </Show>
+      <Title component="h1">{props.src.title}</Title>
+      <Body1 component="p">{props.src.description}</Body1>
+    </a>
+  );
+}
+
 /**
  * find bottom-to-top the element with `data-action`.
  */
@@ -328,7 +420,7 @@ const RegularToot: Component<TootCardProps> = (props) => {
           class={tootStyle.tootContent}
         />
         <Show when={toot().card}>
-          <PreviewCard src={toot().card!} />
+          <TootPreviewCard src={toot().card!} />
         </Show>
         <Show when={toot().mediaAttachments.length > 0}>
           <MediaAttachmentGrid attachments={toot().mediaAttachments} />
diff --git a/src/timelines/toot-components/PreviewCard.css b/src/timelines/toot-components/PreviewCard.css
deleted file mode 100644
index 17d9f2b..0000000
--- a/src/timelines/toot-components/PreviewCard.css
+++ /dev/null
@@ -1,67 +0,0 @@
-.PreviewCard {
-  display: block;
-  border: 1px solid #eeeeee;
-  background-color: var(--tutu-color-surface);
-  text-decoration: none;
-  border-radius: 4px;
-  overflow: hidden;
-  margin-top: 1em;
-  margin-bottom: 1.5em;
-  color: var(--tutu-color-secondary-text-on-surface);
-  transition: color 220ms var(--tutu-anim-curve-std), background-color 220ms var(--tutu-anim-curve-std);
-  padding-bottom: 8px;
-  overflow: hidden;
-  z-index: 1;
-  position: relative;
-
-  >img {
-    background-color: #eeeeee;
-    max-width: 100%;
-    height: auto;
-  }
-
-  &:hover,
-  &:focus-visible {
-    background-color: var(--tutu-color-surface-d);
-    color: var(--tutu-color-on-surface);
-
-    >h1 {
-      text-decoration: underline;
-    }
-  }
-
-  >h1 {
-    color: var(--tutu-color-on-surface);
-    max-height: calc(4 * var(--title-line-height) * var(--title-size));
-  }
-
-  >p {
-    max-height: calc(8 * var(--body-line-height) * var(--body-size));
-  }
-
-  >h1,
-  >p {
-    margin-left: 16px;
-    margin-right: 16px;
-    overflow: hidden;
-    text-overflow: ellipsis;
-  }
-
-  &.compact {
-    display: grid;
-    grid-template-columns: minmax(10%, 30%) 1fr;
-    padding-left: 16px;
-    padding-right: 16px;
-    padding-top: 8px;
-
-    >img:first-child {
-      grid-row: 1 / 3;
-      object-fit: contain;
-    }
-
-    >h1,
-    >p {
-      margin-right: 0;
-    }
-  }
-}
diff --git a/src/timelines/toot-components/PreviewCard.tsx b/src/timelines/toot-components/PreviewCard.tsx
deleted file mode 100644
index ed20eb8..0000000
--- a/src/timelines/toot-components/PreviewCard.tsx
+++ /dev/null
@@ -1,97 +0,0 @@
-import Color from "colorjs.io";
-import type { mastodon } from "masto";
-import { createEffect, createMemo, Show } from "solid-js";
-import { Title, Body1 } from "../../material/typography";
-import { averageColorHex } from "../../platform/blurhash";
-import "./PreviewCard.css";
-
-export function PreviewCard(props: {
-  src: mastodon.v1.PreviewCard;
-  alwaysCompact?: boolean;
-}) {
-  let root: HTMLAnchorElement;
-
-  createEffect(() => {
-    if (props.alwaysCompact) {
-      root.classList.add("compact");
-      return;
-    }
-    if (!props.src.width) return;
-    const width = root.getBoundingClientRect().width;
-    if (width > props.src.width) {
-      root.classList.add("compact");
-    } else {
-      root.classList.remove("compact");
-    }
-  });
-
-  const imgAverageColor = createMemo(() => {
-    if (!props.src.image) return;
-    return new Color(averageColorHex(props.src.blurhash));
-  });
-
-  const prefersWhiteText = createMemo(() => {
-    const oc = imgAverageColor();
-    if (!oc) return;
-    const colorWhite = new Color("white");
-
-    return colorWhite.luminance / oc.luminance > 3.5;
-  });
-
-  const focusSurfaceColor = createMemo(() => {
-    const oc = imgAverageColor();
-    if (!oc) return;
-    if (prefersWhiteText()) {
-      return new Color(oc).darken(0.2);
-    } else {
-      return new Color(oc).lighten(0.2);
-    }
-  });
-
-  const textColorName = createMemo(() => {
-    const useWhiteText = prefersWhiteText();
-    if (typeof useWhiteText === "undefined") {
-      return;
-    }
-    return useWhiteText ? "white" : "black";
-  });
-
-  const secondaryTextColor = createMemo(() => {
-    const tcn = textColorName();
-    if (!tcn) return;
-    const tc = new Color(tcn);
-    tc.alpha = 0.75;
-    return tc;
-  });
-
-  return (
-    <a
-      ref={root!}
-      class={"PreviewCard"}
-      href={props.src.url}
-      target="_blank"
-      referrerPolicy="unsafe-url"
-      style={{
-        "--tutu-color-surface": imgAverageColor()?.toString(),
-        "--tutu-color-surface-d": focusSurfaceColor()?.toString(),
-        "--tutu-color-on-surface": textColorName(),
-        "--tutu-color-secondary-text-on-surface":
-          secondaryTextColor()?.toString(),
-      }}
-    >
-      <Show when={props.src.image}>
-        <img
-          crossOrigin="anonymous"
-          src={props.src.image!}
-          width={props.src.width || undefined}
-          height={props.src.height || undefined}
-          loading="lazy"
-        />
-      </Show>
-      <Title component="h1">{props.src.title}</Title>
-      <Body1 component="p">{props.src.description}</Body1>
-    </a>
-  );
-}
-
-export default PreviewCard;
diff --git a/src/timelines/toot.module.css b/src/timelines/toot.module.css
index ecd74a1..cb3c70d 100644
--- a/src/timelines/toot.module.css
+++ b/src/timelines/toot.module.css
@@ -238,6 +238,35 @@
   }
 }
 
+.tootAttachmentGrp {
+  /* Note: MeidaAttachmentGrid has hard-coded layout calcalation */
+  composes: cardNoPad from "../material/cards.module.css";
+  margin-top: 1em;
+  margin-left: calc(var(--card-pad, 0) + var(--toot-avatar-size, 0) + 8px);
+  margin-right: var(--card-pad, 0);
+  gap: 4px;
+
+  > :where(img, video) {
+    max-height: 35vh;
+    min-height: 40px;
+    min-width: 40px;
+    object-fit: contain;
+    max-width: 100%;
+    background-color: var(--tutu-color-surface-d);
+    border-radius: 2px;
+    border: 1px solid var(--tutu-color-surface-d);
+    transition: outline-width 60ms var(--tutu-anim-curve-std), border-color 60ms var(--tutu-anim-curve-std);
+    contain: strict;
+    content-visibility: auto;
+
+    &:hover,
+    &:focus-visible {
+      outline: 8px solid var(--media-color-accent, var(--tutu-color-surface-d));
+      border: none;
+    }
+  }
+}
+
 .tootBottomActionGrp {
   composes: cardGutSkip from "../material/cards.module.css";
   padding-block: calc((var(--card-gut) - 10px) / 2);