样式兼容开头

html {
  box-sizing: border-box;
}
*, *:before, *:after {
  box-sizing: inherit;
}
body, div, ul, li, h1, h2, h3, h4, h5, h6, pre, form, fieldset, input, textarea, p, blockquote, th, td { padding:0;margin:0; }
ul,li{ list-style: none;list-style-type:none;}