.banner {
    width: 100%;
    height: 300px;
    background: url("../images/partybg.jpg") no-repeat top center;
    background-size: cover;
    overflow: hidden;
    margin-top: 100px;
}

.main .warp .nav .nav-box {
    display: inline-block;
    width: 650px;
    height: 70px;
    box-sizing: border-box;
    font-size: 16px;
    cursor: pointer;
}

.main .warp  .nav .nav-box:first-of-type,
.main .warp  .nav .nav-box:last-of-type {
    /* width: 649px; */
    width: 432px;
}
 

.main .warp  .nav .nav-bg {
    background-color: #ff3f3f;
    /* width: 652px; */
    width: 435px;
    height: 70px;
    position: absolute;
    top: -1px;
    left: -1px;
}
.main .warp  .nav .nav-bg i {
    width: 15px;
    height: 14px;
    display: inline-block;
    background: url("../images/icon.png") no-repeat -675px -90px;
    /* margin: 70px 0 0 320px; */
    margin: 70px 0 0 213px;
}