1.样式初置 body,div,ul,ol,h1,h2,h3,h4,h5,p,form,input,textarea,select{margin:0;padding:0;} li{list-style:none;} a{text-decoration:none;} img{border:none;vertical-align:top;} input,textarea{outline:none;} textarea{resize:none;overflow:auto;} body{font-siz