css

.cf:before, .cf:after {
    content: " ";
    display: table;
}

.cf:after {
    clear: both;
}

.cf {
    *zoom: 1;
}

.dn {
    display: none;
}

.db {
    display: block;
}

.fl {
    float: left;
    _display: inline;
}

.fr {
    float: right;
    _display: inline;
}

.fw6 {
    font-weight: 600;
}

.lh-title {
    line-height: 1.25;
}

.lh-copy {
    line-height: 1.5;
}

.mw9 {
    max-width: 96rem;
}

.w-100 {
    width: 100%;
}

.pa3 {
    padding: 1rem;
}

.mb4 {
    margin-bottom: 2rem;
}

.mt0 {
    margin-top: 0;
}

.f2 {
    font-size: 2.25rem;
}

.f6 {
    font-size: .875rem;
}

.center {
    margin-right: auto;
    margin-left: auto;
}

@media screen and (min-width: 30em) {
    .db-ns {
        display: block;
    }

    .fl-ns {
        float: left;
        _display: inline;
    }

    .mb5-ns {
        margin-bottom: 4rem;
    }
}

@media screen and (min-width: 30em) and (max-width: 60em) {
    .w-50-m {
        width: 50%;
    }

    .pa4-m {
        padding: 2rem;
    }

    .pr3-m {
        padding-right: 1rem;
    }
}

@media screen and (min-width: 60em) {
    .db-l {
        display: block;
    }

    .w-20-l {
        width: 20%;
    }

    .w-80-l {
        width: 80%;
    }

    .pa5-l {
        padding: 4rem;
    }

    .pr5-l {
        padding-right: 4rem;
    }

    .f1-l {
        font-size: 3rem;
    }
}