點擊一組縮圖，大圖顯示並切換到對應的圖，再點擊該縮圖大圖隱藏。當大圖顯示時，點擊其它小圖，大圖切換但不隱藏。我的問題是：當大圖顯示時，點擊其它小圖，大圖切換但不隱藏，但二次點擊該縮圖大圖隱藏，這種效果怎麼實現？
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