腾讯：
body,ol,ul,li,h1,h2,h3,h4,h5,h6,p,th,td,dl,dd,form,fieldset,legend,input,textarea,select{ margin: 0; padding: 0 } img{ border: 0; vertical-align: top } li{ list-style: none } iframe{ border: none } html{ height: 100%; font-size: 16px } body{ height: 100%; font: 400 1em/1.8 'Microsoft Yahei', 'PingFang SC', 'Avenir', 'Segoe UI', 'Hiragino Sans GB', STHeiti, 'Microsoft Sans Serif', 'WenQuanYi Micro Hei', sans-serif } a{ color: #333; text-decoration: none } a:hover{ color: #0c82ff } .cf:after,.cf:before{ content: " "; display: table } .cf:after,.clearfix:after{ clear: both } .fl{ float: left } .fr{ float: right } h1,h2,h3,h4,h5{ font-size: 100%; font-weight: normal }淘宝：
blockquote,body,button,dd,dl,dt,fieldset,form,h1,h2,h3,h4,h5,h6,hr,input,legend,li,ol,p,pre,td,textarea,th,ul{ margin: 0; padding: 0 } body,button,input,select,textarea{ font: 12px/1.5 tahoma,arial,'Hiragino Sans GB','\5b8b\4f53',sans-serif } h1,h2,h3,h4,h5,h6{ font-size: 100% } address,cite,dfn,em,var{ font-style: normal } code,kbd,pre,samp{ font-family: courier new,courier,monospace } small{ font-size: 12px } ol,ul{ list-style: none } a{ text-decoration: none } a:hover{ text-decoration: underline } sup{ vertical-align: text-top } sub{ vertical-align: text-bottom } legend{ color: #000 } fieldset,img{ border: 0 } button,input,select,textarea{ font-size: 100% } button{ border-radius: 0 } table{ border-collapse: collapse; border-spacing: 0 }网易：
body{ line-height: 1.5; font-family: arial,"\5B8B\4F53"; background: #ffffff; font-size: 12px; } body,div,dl,dt,dd,ul,ol,li,h1,h2,h3,h4,h5,h6,pre,code,form,fieldset,legend,input,button,textarea,p,blockquote,th,td{ margin: 0; padding: 0; } h1,h2,h3,h4,h5,h6{ font-size: 100%; } ol,ul{ list-style: none; } address,caption,cite,code,dfn,em,strong,th,var,optgroup{ font-style: normal; } input,button,textarea,select,optgroup,option{ font-family: inherit; font-size: inherit; font-style: inherit; font-weight: inherit; *font-size: 100%; } fieldset,img,a img,:link img,:visited img{ border: 0; } a{ text-decoration: none; } a:hover{ text-decoration: underline; } :focus{ outline: 0; } table{ border-collapse: collapse; border-spacing: 0; } caption,th{ text-align: left; } sup,sub{ font-size:100%; vertical-align: baseline; } blockquote,q{ quotes: none; } blockquote:before,blockquote:after,q:before,q:after{ content: ''; content: none; } .clear,.clearfix:after{ clear: both; height: 0; overflow: hidden; display: block; } .clearfix:after{ visibility: hidden; content: "."; } .clearfix{ *zoom: 1; }
