Simon Willison’s Weblog

23rd September 2026

Tool Shadow roots, explained with live examples — Learn about shadow DOM through interactive examples that demonstrate style encapsulation, inheritance, slots, parts, and JavaScript access. Explore how shadow roots create isolated DOM trees with private stylesheets and elements that interact with the page DOM in specific, controlled ways.

Prompt to Fable 5.1 Medium:

Build an artifact to explain shadow roots in CSS with interactive examples

Posted 23rd September 2026 at 4:37 pm

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This is a beat by Simon Willison, posted on 23rd September 2026.

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