How i got scammed

I am one of those who got too excited when I see an airdrop on twitter. When I clicked the link on the tweet, a website opened asked me to connect my wallet to participate and as soon as I connected my metamask account a money transfer popup opened and I got suspicious. After verifying the twitter account on the screenshot I attached I was sure it was fake and I closed the website on my metamask browser but it was too late. I checked my wallet and my 2.5 eth was gone in an instant.

How is it possible for them to empty my account even though I didnt clicked any button on the transfer popup. I only connected my wallet and didnt click any button on the metamask transfer popup.

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