css-alpha-masking

Apply CSS alpha masks with linear-gradient for horizontal or vertical edge fades.

4.5k|536|Updated Feb 3, 2026
One-click install
npx skills add https://github.com/MengTo/Skills --skill css-alpha-masking-mengto
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: css-alpha-masking
Source: https://github.com/MengTo/Skills/tree/main/agent-skills/web-design/css-alpha-masking
Command: npx skills add https://github.com/MengTo/Skills --skill css-alpha-masking-mengto

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

CSS alpha masking lets you smoothly fade the edges of an element using gradients, avoiding hard cutoffs and improving visual polish for things like scrollable fades or image edge transitions.

Core Features & Use Cases

  • Gradient-based edge fades: Apply horizontal or vertical fades using linear-gradient.
  • Safari-compatible masking: Use both mask-image and -webkit-mask-image for consistent rendering.
  • Minimal, controllable customization: Tune fade direction and stop percentages (and optional strength) without rewriting the entire style.

Quick Start

Add the provided mask-image and -webkit-mask-image linear-gradient styles to the element you want to fade, then adjust direction and stop percentages until the edges match your design.

Frequently Asked Questions about css-alpha-masking

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I fade the edges of an element using CSS alpha masking?

You fade element edges by applying a linear-gradient to the mask-image property, which controls the transparency transition horizontally or vertically to smooth out hard cutoffs.

Why does my CSS mask-image not work in Safari?

CSS mask-image fails in Safari without the vendor prefix, so you must set both standard mask-image and -webkit-mask-image with identical linear-gradient values to ensure consistent cross-browser rendering.

How do I control the fade depth and direction of a CSS linear-gradient mask?

Control fade depth and direction by tuning the linear-gradient angle for vertical or horizontal transitions and adjusting the gradient stop percentages to determine where the alpha masking begins and ends.

Can I use CSS alpha masking for scroll-edge fades on cropped containers?

Yes, CSS alpha masking is suitable for scroll-edge fades and cropped UI containers, using linear-gradient masks to smoothly blend element boundaries without hard visual cutoffs.

What is the best way to apply smooth edge fading without hard cutoffs in web design?

The best way to achieve smooth edge fading is using CSS alpha masking with linear-gradient, adjusting stop percentages and gradient direction to blend element edges seamlessly for polished UI visuals.