When King Bhumibol Adulyadej checked out of a hospital in a pink blazer, he made a fashion statement that resonated around Thailand. Pink shirts instantly became this season's must-have item, and crowds are mobbing shops that sell them.

In recent appearances, Bhumibol has sported a range of pastel sport coats, changing his style after decades in dark suits and setting new trends with each outing. As the country gears up to celebrate Bhumibol's 80th birthday Wednesday, many Thais are honoring their monarch by dressing like him. "Now the T-shirt craze is green," the Nation newspaper said in a front-page headline after the king stepped out in a sea-green-colored blazer. Days later, when he opted for baby blue, the paper forecast "a run on blue shirts."

Bhumibol, the world's longest-serving monarch, enjoys a reverence seldom seen in modern times. He has no formal political role, but is considered the country's moral authority. Some regard him as semi-divine.

Pastel shirts are being sold nationwide, but the most desirable come from Phufa, a shop owned by Crown Princess Maha Chakri Sirindhorn. The shop sold 40,000 pink shirts in November, a spokeswoman said. "Our factory is making these shirts every day, every minute," she said.

On a recent day, hundreds lined up outside. First in line was Rose Tarin, 56, who had camped out since 4 a.m. "Wearing pink brings the king luck. I don't want him to be sick," she said. "I love the king. I want him to stay with the Thai people forever."