Simon Willison’s Weblog

So you think you know box shadows? (via) David Gerrells dives deep into CSS box shadows. How deep? Implementing a full ray tracer with them deep.

Posted 21st July 2024 at 4:23 pm

Recent articles

The Summer of Johann: prompt injections as far as the eye can see - 15th August 2025
Open weight LLMs exhibit inconsistent performance across providers - 15th August 2025
LLM 0.27, the annotated release notes: GPT-5 and improved tool calling - 11th August 2025

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