Three and a half weeks after the royal wedding, Kate fashion fever continues apace!

After the Duchess, 29, stunned during a Buckingham Palace meet-and-greet with President Barack Obama and First Lady Michelle on Tuesday -- the first appearance she and Prince William made after their honeymoon -- fans worldwide are anxious to get her look.

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How anxious? The nude, form-fitting, $340 Reiss dress that showed off Kate's golden tan (acquired in the Seychelles) and super-slim body has sold out online stateside -- and even crashed the company's website!

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A Reiss spokesperson told the Washington Post that their website traffic spiked by more than 300 percent as a result of Kate's dress, called the "Shola."

The line even Tweeted Wednesday: "To all our Shola fans!...The dress has now sold out online and in the US, with very limited stock left in UK stores." Reiss is struggling to keep their suddenly-flooded website up.

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Tell Us: Did you love Kate's "Shola" dress?

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