@media (max-width: 23px) {
    .second-nav ul li{
        float: left;
        width: 33%;
        text-align: center;
        line-height: 42px;
        font-size: 15px;
        /* border-left: 1px solid red ;*/
    }
}

@media(min-width: 24px) {
    .second-nav ul{
        width: 40%;
    }
    .second-nav ul li{
        width: 33%;
    }
}