#first-block, #second-block, #third-block, #fourth-block {
    text-align:center;
    padding:3.5em 0;
    }
    #carousel {
    text-align:center;
    }
    #first-block {
    }
    #second-block {
    }
    #third-block {
    }
    #fourth-block {
    }
    footer {
    padding:3.5em 0;
    }