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Optical Illusions

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About

A few classic illusions where your visual system fills in things that aren't there: the café wall (parallel lines that look slanted) and the Hermann / scintillating grids (phantom blobs at the crossings).

How it works

Every illusion is plain markup — coloured divs, grids and borders, no images. The effects are entirely in your retina and visual cortex, not in the pixels.

Metadata
title
Optical Illusions
description
A small gallery of classic optical illusions — café wall, Hermann grid, scintillating grid — drawn entirely in CSS. No images.
canonical
https://kaspirius.com/illusions
updated
Last updated
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Structured data (JSON-LD)
TechArticle

Same as Article, flagged as technical/developer reference material.

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  "@context": "https://schema.org",
  "@type": "TechArticle",
  "headline": "Optical Illusions — toy",
  "description": "A small gallery of classic optical illusions — café wall, Hermann grid, scintillating grid — drawn entirely in CSS. No images.",
  "url": "https://kaspirius.com/illusions",
  "mainEntityOfPage": {
    "@type": "WebPage",
    "@id": "https://kaspirius.com/illusions"
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  "datePublished": "2026-06-18",
  "dateModified": "2026-06-18",
  "author": {
    "@type": "Person",
    "name": "kaspirius",
    "url": "https://kaspirius.com"
  },
  "publisher": {
    "@type": "Organization",
    "name": "kaspirius",
    "url": "https://kaspirius.com"
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}
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