Add Śrī Yantra · two poles

Narrated Manim explainer, 2:09, 1280x720.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01161aC97vUnBnyZRBGyJeHy

README.md

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 # videos
 
-Narrated Manim maths explainers
+Narrated Manim maths explainers. Click a `.mp4` to play it in the browser.
+
+| Video | Length | What it shows |
+| --- | --- | --- |
+| [Śrī Yantra · two poles](yantra-two-poles.mp4) | 2:09 | The Śrī Yantra inverted in its own circle, then lifted onto a sphere: circle inversion becomes a top-to-bottom flip, and the bindu and infinity become the two poles of one sphere. |