*{
    margin: 0;
    padding: 0;
    list-style: none;
}
a{
    text-decoration: none;
}
.main{
    width: 900px;
    margin: auto;
}
header{
    width: 100%;
    height: 70px;
    background: #fffffd;
    line-height: 70px;
}
.company{
    float: left;
}
.company>a{
    font-size: 15px;
    font-weight: 600;
    color: #ffaf00;
}
.back{
    float: right;
    font-size: 14px;
}
.back a{
    color: #666666;
}
.back a:hover{
    text-decoration: underline;
    color: #551A8B;
}