Progressive Blur `.mv-progressive-blur`

CSS のみの、端に向かって段階的に強くなるぼかしです。スライス状にマスクした backdrop-filter のレイヤーを重ね、任意の辺に適用でき、背景色へのフェードも任意で加えられます。

カテゴリー	エフェクト
タイプ	CSS のみ（`.mv-progressive-blur`）
ステータス	安定版
Keywords	blur, progressive-blur, gradual-blur, edge-blur, backdrop-filter, scroll, fade

When to use

A scrolling list or feed should soften into its edge instead of being cut off abruptly
A caption sits at the bottom of an image and the photo should gradually blur beneath it
A sticky header or bottom bar should blend smoothly into the content scrolling behind it

Avoid when

A scroll container only needs a thin scrollbar and a simple edge fade → use Scroll Area instead
The whole surface should be frosted evenly rather than blurred toward one edge → use Glass instead
Important text or controls would land in the blurriest part of the band

インストール

node scripts/add.mjs progressive-blur --out ./src/marvelous

Marvelous UI の MCP サーバーを使う AI エージェント：install_components({ slugs: ["progressive-blur"], target_dir: "<absolute path>/src/marvelous", framework: "react" })。

コピーされるファイル（依存関係を含む）：tokens/tokens.css、core/base.css、components/progressive-blur/progressive-blur.css。

使い方

基本となるマークアップです。ここから属性、data-*、CSS 変数でカスタマイズしてください：

<div style="display:flex;flex-wrap:wrap;gap:1.5rem;justify-content:center;align-items:stretch;width:100%">
  <!-- Scrolling list with blurred top and bottom edges -->
  <div class="mv-card" style="position:relative;width:min(100%,20rem);height:22rem">
    <div style="height:100%;overflow:auto;padding:2.5rem 1.25rem 4rem" tabindex="0" aria-label="Changelog">
      <h3 style="margin:0 0 1rem;font-size:var(--mv-text-base)">Changelog</h3>
      <ol style="margin:0;padding:0;list-style:none;display:grid;gap:1rem;font-size:var(--mv-text-sm)">
        <li><strong>v4.2</strong>: PDF export for dashboards.<br><span style="color:var(--mv-fg-muted)">Sep 18, 2026</span></li>
        <li><strong>v4.1</strong>: Offline mode for the mobile app.<br><span style="color:var(--mv-fg-muted)">Sep 2, 2026</span></li>
        <li><strong>v4.0</strong>: New real-time collaborative editor.<br><span style="color:var(--mv-fg-muted)">Aug 21, 2026</span></li>
        <li><strong>v3.9</strong>: SSO sign-in via SAML and OpenID.<br><span style="color:var(--mv-fg-muted)">Jul 30, 2026</span></li>
        <li><strong>v3.8</strong>: 3× faster full-text search.<br><span style="color:var(--mv-fg-muted)">Jul 12, 2026</span></li>
        <li><strong>v3.7</strong>: Automatic dark theme.<br><span style="color:var(--mv-fg-muted)">Jun 25, 2026</span></li>
        <li><strong>v3.6</strong>: Signed webhooks and audit logs.<br><span style="color:var(--mv-fg-muted)">Jun 3, 2026</span></li>
      </ol>
    </div>
    <div class="mv-progressive-blur" data-side="top" data-fade aria-hidden="true" style="--mv-progressive-blur-size:2.25rem;--mv-progressive-blur-strength:8px"><i></i><i></i><i></i><i></i></div>
    <div class="mv-progressive-blur" data-fade aria-hidden="true" style="--mv-progressive-blur-size:6rem"><i></i><i></i><i></i><i></i><i></i><i></i></div>
  </div>

  <!-- Artwork with a caption over a progressive blur -->
  <figure style="position:relative;margin:0;width:min(100%,20rem);height:22rem;border-radius:var(--mv-radius-xl);overflow:hidden;box-shadow:var(--mv-shadow-lg);background:radial-gradient(60% 50% at 30% 30%,oklch(0.85 0.15 85),transparent 70%),radial-gradient(70% 60% at 80% 70%,oklch(0.6 0.22 330),transparent 70%),linear-gradient(160deg,oklch(0.55 0.2 280),oklch(0.35 0.15 250))">
    <div aria-hidden="true" style="position:absolute;inset:0;background:repeating-linear-gradient(90deg,oklch(1 0 0 / .18) 0 3px,transparent 3px 22px)"></div>
    <div aria-hidden="true" style="position:absolute;left:18%;top:42%;width:8rem;height:8rem;border-radius:50%;background:oklch(0.96 0.03 90)"></div>
    <div class="mv-progressive-blur" aria-hidden="true" style="--mv-progressive-blur-size:45%;--mv-progressive-blur-strength:24px"><i></i><i></i><i></i><i></i><i></i><i></i></div>
    <figcaption style="position:absolute;inset:auto 0 0 0;z-index:3;padding:1.25rem;color:white;text-shadow:0 1px 10px oklch(0 0 0 / .35)">
      <strong style="display:block;font-size:var(--mv-text-lg)">Midnight Sun</strong>
      <span style="font-size:var(--mv-text-sm);opacity:.85">“Latitudes” series · limited edition</span>
    </figcaption>
  </figure>
</div>

API

Attributes

Name	タイプ	Default	Description
`data-side`	top \| bottom \| left \| right	`bottom`	Edge toward which the blur increases.
`data-fade`	boolean		Adds a gradient to the background color (scrolling lists).

CSS classes

Name	Description
`mv-progressive-blur`	Absolute layer to place inside a positioned parent (that clips its corners). Holds 1 to 8 empty children (`<i>`): one blur layer each; 6 gives a very smooth gradient. With no children, 2 layers via pseudo-elements.

CSS variables

Name	Default	Description
`--mv-progressive-blur-size`	`35%`	Height (or width) of the band.
`--mv-progressive-blur-strength`	`16px`	Maximum blur, at the edge.
`--mv-progressive-blur-fade`	`var(--mv-bg)`	Fade color (data-fade).
`--mv-progressive-blur-z`	`2`	Layer z-index.

Accessibility

Decorative: aria-hidden and pointer-events: none, so the content underneath stays clickable and scrollable. No animation. Keep important text out of the blurriest area (or place the caption above it, as in the demo).