background-blend-composer

Design layered backgrounds that make PNG assets blend naturally. Use when hero assets float awkwardly on gradients, multiple images don't blend, or need seamless foreground/background integration. Out

SKILL.md

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Background & Blend Composer (Hintergrund-Mischer)

Design layered backgrounds that make PNG assets blend naturally.

When to Use

  • Hero asset floating on random gradient
  • Multiple images that don't blend
  • Need seamless foreground/background integration
  • Harsh edges between images and backgrounds

Process

1. Analyze Assets

For each asset, identify:

  • Background type: Transparent, white, dark, colored
  • Color palette: Dominant colors, edge colors
  • Style: Flat, detailed, textured, gradient

2. Design Layer Stack

Build from back to front:

Layer 1: SOLID BASE
├── Single color matching darkest asset tones
├── Purpose: Unifying foundation

Layer 2: GRADIENT ATMOSPHERE
├── Subtle gradient adding depth
├── Direction should complement composition

Layer 3: SIDE/BACKGROUND ASSETS
├── Images that frame the composition
├── Use appropriate blend modes
├── Mask edges for seamless blending

Layer 4: HERO/FOREGROUND ASSET
├── Main focal point
├── Handle background removal
├── Add edge blending if needed

Layer 5: OVERLAYS/EFFECTS
├── Atmospheric effects (mist, particles)
├── Vignettes, glows

3. Blend Mode Selection

Asset Background Blend Mode Why
White multiply White becomes transparent
Black screen or lighten Black becomes transparent
Transparent normal Already clean
Dark (matching base) lighten Shows lighter elements

4. Edge Blending Techniques

For white backgrounds with multiply:

/* Problem: Harsh rectangular edge */
/* Solution: Edge-tinting overlay */
.hero-container {
  position: relative;
}
.hero-container::after {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(
    ellipse 70% 80% at 50% 50%,
    transparent 40%,
    rgba(BASE_COLOR, 0.6) 70%,
    BASE_COLOR 100%
  );
  mix-blend-mode: multiply;
  pointer-events: none;
}

For side images:

mask-image: linear-gradient(
  to right, /* or to left */
  black 0%,
  black 60%,
  transparent 100%
);

5. Z-Index Strategy

z-0: Base color, gradients
z-1: Background assets (trees, mountains)
z-2: Hero/main asset
z-3: Atmospheric effects
z-4: UI elements

Common Problems & Fixes

Problem Cause Fix
Hard rectangular edges No edge blending Add gradient mask or tinting overlay
Hero too faded Blend mode too aggressive Limit blend to edges only
Colors don't match Different palettes Sample from assets, unify base
"Floating" asset No grounding Add soft shadow or ambient glow
Muddy center Too many layers Reduce count, increase contrast

Example: Ice Climber Dashboard

Assets:

  • Hero: Ice climber (white bg, teal/cyan)
  • Left: Night forest (dark navy)
  • Right: Pine trees (dark navy)

Solution:

Layer 1: #0c1e2b (base)
Layer 2: Radial glow at center
Layer 3: Left/right images (z-1, lighten, edge masks)
Layer 4: Hero (z-2, multiply + edge tint overlay)
Layer 5: Stars, snow particles (z-3+)