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.chart-panel.pi-style__card
Chart cells that contain a card chart type
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.chart-panel.pi-style__card .paper-button
The buttons that appear on a card chart type only.
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.chart-panel.pi-style__card:hover .paper-button
As above; but only when you move your cursor over the card chart type only
.pi-style__card__chart-title
The heading on a card chart type only.
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