a,
address,
b,
big,
blockquote,
body,
center,
cite,
code,
dd,
del,
div,
dl,
dt,
em,
fieldset,
font,
form,
h1,
h2,
h3,
h4,
h5,
h6,
html,
i,
iframe,
img,
ins,
label,
legend,
li,
ol,
p,
pre,
small,
span,
strong,
u,
ul,
var {
  margin: 0;
  padding: 0;
}

.w {
  width: 1240px;
  margin: 0px auto;
}

.w::after {
  content: "";
  display: block;
  clear: both;
}

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

a {
  text-decoration: none;
  color: gray;

}


* {
  box-sizing: border-box;
}

ul {
  list-style-type: none;
}