Progressive Blur

---
name: progressive-blur
description: Create a layered CSS progressive blur (top or bottom) using
  multiple backdrop-filter masks for depth and softness. Use when asked for
  “progressive blur”, “gradient blur overlay”, or stepped blur masks that fade
  from an edge of the viewport.
---

# Progressive Blur Skill

## Workflow
1. Confirm placement (top or bottom), height, and z-index relative to UI.
2. Provide the matching snippet and a short usage checklist.
3. Offer only targeted tweaks (height, blur steps, direction, opacity stops).

## Usage checklist
- Insert the HTML inside `<body>`.
- Keep the `.gradient-blur` element near the top of the DOM.
- Ensure the background behind it exists (backdrop-filter blurs what is behind).
- Adjust `z-index` to sit above content but below modals.

## Top blur (from top)
```html
<div class="gradient-blur">
  <div></div><div></div><div></div><div></div><div></div><div></div>
</div>
<style>
  .gradient-blur {
    position: fixed;
    z-index: 5;
    inset: 0 0 auto 0;
    height: 12%;
    pointer-events: none;
  }

  .gradient-blur > div,
  .gradient-blur::before,
  .gradient-blur::after {
    position: absolute;
    inset: 0;
  }

  .gradient-blur::before {
    content: "";
    z-index: 1;
    backdrop-filter: blur(0.5px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 0%,
      rgba(0, 0, 0, 1) 12.5%,
      rgba(0, 0, 0, 1) 25%,
      rgba(0, 0, 0, 0) 37.5%);
  }

  .gradient-blur > div:nth-of-type(1) {
    z-index: 2;
    backdrop-filter: blur(1px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 12.5%,
      rgba(0, 0, 0, 1) 25%,
      rgba(0, 0, 0, 1) 37.5%,
      rgba(0, 0, 0, 0) 50%);
  }

  .gradient-blur > div:nth-of-type(2) {
    z-index: 3;
    backdrop-filter: blur(2px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 25%,
      rgba(0, 0, 0, 1) 37.5%,
      rgba(0, 0, 0, 1) 50%,
      rgba(0, 0, 0, 0) 62.5%);
  }

  .gradient-blur > div:nth-of-type(3) {
    z-index: 4;
    backdrop-filter: blur(4px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 37.5%,
      rgba(0, 0, 0, 1) 50%,
      rgba(0, 0, 0, 1) 62.5%,
      rgba(0, 0, 0, 0) 75%);
  }

  .gradient-blur > div:nth-of-type(4) {
    z-index: 5;
    backdrop-filter: blur(8px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 50%,
      rgba(0, 0, 0, 1) 62.5%,
      rgba(0, 0, 0, 1) 75%,
      rgba(0, 0, 0, 0) 87.5%);
  }

  .gradient-blur > div:nth-of-type(5) {
    z-index: 6;
    backdrop-filter: blur(16px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 62.5%,
      rgba(0, 0, 0, 1) 75%,
      rgba(0, 0, 0, 1) 87.5%,
      rgba(0, 0, 0, 0) 100%);
  }

  .gradient-blur > div:nth-of-type(6) {
    z-index: 7;
    backdrop-filter: blur(32px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 75%,
      rgba(0, 0, 0, 1) 87.5%,
      rgba(0, 0, 0, 1) 100%);
  }

  .gradient-blur::after {
    content: "";
    z-index: 8;
    backdrop-filter: blur(64px);
    mask: linear-gradient(to top,
      rgba(0, 0, 0, 0) 87.5%,
      rgba(0, 0, 0, 1) 100%);
  }
</style>
```

## Bottom blur (from bottom)
```html
<div class="gradient-blur">
  <div></div><div></div><div></div><div></div><div></div><div></div>
</div>
<style>
  .gradient-blur {
    position: fixed;
    z-index: 5;
    inset: auto 0 0 0;
    height: 65%;
    pointer-events: none;
  }

  .gradient-blur > div,
  .gradient-blur::before,
  .gradient-blur::after {
    position: absolute;
    inset: 0;
  }

  .gradient-blur::before {
    content: "";
    z-index: 1;
    backdrop-filter: blur(0.5px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 0%,
      rgba(0, 0, 0, 1) 12.5%,
      rgba(0, 0, 0, 1) 25%,
      rgba(0, 0, 0, 0) 37.5%);
  }

  .gradient-blur > div:nth-of-type(1) {
    z-index: 2;
    backdrop-filter: blur(1px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 12.5%,
      rgba(0, 0, 0, 1) 25%,
      rgba(0, 0, 0, 1) 37.5%,
      rgba(0, 0, 0, 0) 50%);
  }

  .gradient-blur > div:nth-of-type(2) {
    z-index: 3;
    backdrop-filter: blur(2px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 25%,
      rgba(0, 0, 0, 1) 37.5%,
      rgba(0, 0, 0, 1) 50%,
      rgba(0, 0, 0, 0) 62.5%);
  }

  .gradient-blur > div:nth-of-type(3) {
    z-index: 4;
    backdrop-filter: blur(4px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 37.5%,
      rgba(0, 0, 0, 1) 50%,
      rgba(0, 0, 0, 1) 62.5%,
      rgba(0, 0, 0, 0) 75%);
  }

  .gradient-blur > div:nth-of-type(4) {
    z-index: 5;
    backdrop-filter: blur(8px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 50%,
      rgba(0, 0, 0, 1) 62.5%,
      rgba(0, 0, 0, 1) 75%,
      rgba(0, 0, 0, 0) 87.5%);
  }

  .gradient-blur > div:nth-of-type(5) {
    z-index: 6;
    backdrop-filter: blur(16px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 62.5%,
      rgba(0, 0, 0, 1) 75%,
      rgba(0, 0, 0, 1) 87.5%,
      rgba(0, 0, 0, 0) 100%);
  }

  .gradient-blur > div:nth-of-type(6) {
    z-index: 7;
    backdrop-filter: blur(32px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 75%,
      rgba(0, 0, 0, 1) 87.5%,
      rgba(0, 0, 0, 1) 100%);
  }

  .gradient-blur::after {
    content: "";
    z-index: 8;
    backdrop-filter: blur(64px);
    mask: linear-gradient(to bottom,
      rgba(0, 0, 0, 0) 87.5%,
      rgba(0, 0, 0, 1) 100%);
  }
</style>
```

## Customization knobs
- Direction: flip `to top` ↔ `to bottom`.
- Height: adjust `.gradient-blur` height percentage.
- Strength: change blur values (0.5px → 64px).
- Steps: add/remove layers to control smoothness.

## Common pitfalls
- `backdrop-filter` needs content behind it; it will not blur a flat background.
- High blur values are GPU-heavy; reduce steps on low-end devices.
- Ensure `pointer-events: none` stays to avoid blocking clicks.

## Questions to ask when specs are missing
- Should the blur start from the top or bottom?
- How tall should the blur area be?
- Is performance a concern on lower-end devices?