*{margin: 0px;padding: 0px;}
.header{width;100%;height:40px;background-color:#ccc;}Does anyone know where this CSS went wrong? ? ? Since there is no response
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Add a float and try. It may not be a block-level element. Also, width:100%; replace it with mine
Do you have the class name .header
.header{width;100%;height:40px;
Look carefully. Is there a colon or a semicolon after width? ? ? What should it be? 》? ? ? ?
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