@media only screen and (max-width: 479px) {
    #block-block-23,
    #block-block-24,
    #block-block-25,
    #block-block-31 {
        width: 100%;
    }

    #block-block-23 img,
    #block-block-24 img,
    #block-block-25 img,
    #block-block-31 img {
        width: 100% !important;
        height: auto !important;
    }
}

@media only screen and (min-width: 480px) and (max-width: 599px) {
    #block-block-23,
    #block-block-24,
    #block-block-25,
    #block-block-31  {
        width: 100%;
    }

    #block-block-23 img,
    #block-block-24 img,
    #block-block-25 img,
    #block-block-31 img {
        width: 100% !important;
        height: auto !important;
    }
}

@media only screen and (min-width: 600px) and (max-width: 959px) {
    #block-block-23 img,
    #block-block-24 img,
    #block-block-25 img,
    #block-block-31 img {
        width: 100% !important;
        height: auto !important;
    }
}

@media only screen and (min-width: 960px){
    .front #body {
        margin-top: -20px;
    }
    
    .front #f4 {
        height: auto;
        margin-left: 20px;
        margin-right: 20px;
        margin-bottom: -1em;
    }

    #block-views-slideshow-block-1 {
        margin-top: 20px;
    }
    
    #block-block-23,
    #block-block-24,
    #block-block-25,
    #block-block-31  {
        float: left;
        width: 448px;
        margin-right: 2px !important;
    }

    #block-block-23 img,
    #block-block-24 img,
    #block-block-25 img,
    #block-block-31 img {
        width: 100% !important;
        height: auto !important;
    }
}