CSS兼容必备完美实现Firefox、IE6、IE8、Mac等主流浏览器，所有元素清零

html, body, div, span, applet, object, iframe,
h1, h2, h3, h4, h5, h6, p, blockquote, pre,
a, abbr, acronym, address, big, cite, code,
del, dfn, em, font, img, ins, kbd, q, s, samp,
small, strike, strong, sub, sup, tt, var,
b, u, i, center,
dl, dt, dd, ol, ul, li,
fieldset, form, label, legend,
table, caption, tbody, tfoot, thead, tr, th, td {
 margin: 0;
 padding: 0;
 border: 0;
 outline: 0;
 font-size: 100%;
 vertical-align: baseline;
 background: transparent;
}
body {
 line-height: 1;
}
ol, ul {
 list-style: none;
}
blockquote, q {
 quotes: none;
}
blockquote:before, blockquote:after,
q:before, q:after {
 content: '';
 content: none;
}

/* remember to define focus styles! */
:focus {
 outline: 0;
}

/* remember to highlight inserts somehow! */
ins {
 text-decoration: none;
}
del {
 text-decoration: line-through;
}

/* tables still need 'cellspacing="0"' in the markup */
table {
 border-collapse: collapse;
 border-spacing: 0;
}