css 样式重置

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;
}

/*clearfix*/

.clearfix:after {
    content: ".";
    display: block;
    height: 0;
    clear: both;
    visibility: hidden;
}

.clearfix {
    *+height: 1%;
}