css基础样式重置，浏览器样式统一及IE下样式优化

/*样式重置*/
body,dl,dd,h1,h2,h3,h4,h5,h6,p,form{margin:0;}
ul,ol{margin:0;padding:0;}
h1,h2,h3,h4,h5,h6{font-weight:400;}
input:focus,button:focus{outline:none;}
a:focus{outline:none;}

/*基础样式*/
body{font-family:"Microsoft Yahei";color:#000;font-size:12px;background:#fff;}/*IE下滚动条占据空间*/
body,html{-ms-overflow-style:scrollbar;}

/*不同浏览器下placeholder颜色*/
::-webkit-input-placeholder {color:#999 !important;} /* WebKit browsers */
:-moz-placeholder {color:#999 !important;} /* Mozilla Firefox 4 to 18 */
::-moz-placeholder {color:#999 !important;} /* Mozilla Firefox 19+ */
:-ms-input-placeholder {color:#999 !important;} /* Internet Explorer 10+ */

/*去除IE下input框X按钮,查看密码眼睛按钮*/
::-ms-clear,::-ms-reveal{display:none;}

/*移除浏览器input number小箭头*/
input[type=number]{-moz-appearance:textfield;}
input[type=number]::-webkit-inner-spin-button, input[type=number]::-webkit-outer-spin-button{-webkit-appearance:none;margin:0;}