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hiyouga merged 1 commit into from
May 20, 2026
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docs: add html2canvas export notes #5

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2 changes: 2 additions & 0 deletions AGENTS.md
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Expand Up @@ -70,6 +70,8 @@ This is the reusable content component layer.
## `src/styles/`

- `global.css`: Global styles, theme variables, slide layout, reusable block styling, top-right abstract mark styling, and export canvas styling.
- Avoid modern CSS color functions in export-visible pseudo-elements because `html2canvas` cannot reliably parse computed values such as `color(srgb ...)`; use `rgb(...)`, `rgba(...)`, or hex instead.

@gemini-code-assist gemini-code-assist Bot May 20, 2026

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medium

The restriction on modern CSS color functions should be applied to all export-visible elements, not just pseudo-elements. While exportPdf.js attempts to normalize color() functions for standard elements, it does not currently handle color-mix() (which is used in .slide-canvas in global.css) or other modern syntaxes like oklch(). Since html2canvas cannot reliably parse these computed values, it is safer to avoid them in any content intended for export.

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- Avoid modern CSS color functions in export-visible pseudo-elements because `html2canvas` cannot reliably parse computed values such as `color(srgb ...)`; use `rgb(...)`, `rgba(...)`, or hex instead.
- Avoid modern CSS color functions (such as `color()`, `color-mix()`, or `oklch()`) in export-visible content because `html2canvas` cannot reliably parse these computed values; use `rgb(...)`, `rgba(...)`, or hex instead.

- Avoid small standalone SVG connector graphics in export-visible slide content because `html2canvas` may drop them during PDF export; prefer full-region SVG overlays with paths positioned in the shared viewBox.

Theme styling is mainly controlled through CSS variables:

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