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This method is quite involved, I wonder if there is a simpler approach… maybe with [intersectionobserver](https://observablehq.com/@mbostock/hello-intersectionobserver)?\n`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":274,"value":"md`\\`colors\\` _is a Map of the visibility status (true, false) of each cell._`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":209,"value":"colors = new Map()","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":260,"value":"md`\\`mutable color\\` _changes each time a new color becomes the new main color._`","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":9,"value":"mutable color = 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