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<html><head><style>div#myDiv {background-color: green;}#myDiv {background-color: yellow;}div[id=myDiv] {background-color: blue;}</style></head><body><div id="myDiv">This is a div</div></body></html><html><head><style>div#myDiv {background-color: green;}#myDiv {background-color: yellow;}div[id=myDiv] {background-color: blue;}</style></head><body><div id="myDiv">This is a div</div></body></html>