.head-nav {
    width: 100%;
    height: 65px;
    background-color: #0f7bd2;
}

.nav-ul {
    width: 1200px;
    margin: auto;
    height: 60px;
}

.nav-ul .nav_item {
    float: left;
    width: 171px;
    height: 65px;
    position: relative;
}

.nav-ul .nav_item  a {
    display: block;
    width: 100%;
    height: 100%;
    color: #fff;
    font-size: 20px;
    font-weight: 400;
    line-height: 60px;
    text-align: center;
}

.nav-ul .nav_item  a:hover {
    background: #1253a9;
    font-weight: bold;
}

.nav-ul .on  a {
    background: #fff;
    font-weight: bold;
}
.nav-ul .on a{
    background: #1253a9;
    font-weight: bold;
}