@media only screen and (max-width: 1200px) {
    header {
        height: 65vh;
    }
    .row {
        margin: 0 15px;
    }
    .hero-text {
        width: 90%;
    }
}
@media only screen and (max-width: 1024px) {
    .mobile-menu span {
        display: block;
    }
    header {
        height: 55vh;
    }
    .menu-items {
        display: none;
    }
    html {
        font-size: 55.5%;
    }
    .client-photo {
        width: 100%;
        float: none;
        text-align: center;
    }
    .client-review {
        width: 100%;
        float: none;
        text-align: center;
    }
    .contact-section form {
        width: 100%;
        margin-left: 0;
    }
}

@media only screen and (max-width: 980px) {
    .span_1_of_4 {
        width: 49.2%;
    }
    .span_1_of_4:nth-child(3){
        margin-left: 0;
    }
    html{
        font-size: 62.5%;
    }
}
@media only screen and (max-width: 768px) {
    header {
        height: 50vh;
    }
    .lettle-description {
        width: 100%;
        margin-left: 0;
    }
    h1 {
        font-size: 3.4rem;
    }
    h2 {
        font-size: 3rem;
    }
    h3 {
        font-size: 2rem;
    }
}
@media only screen and (max-width: 480px) {
    header {
        height: 80vh;
    }
    .span_1_of_4 {
        width: 100%;
    }
    h1 {
        font-size: 3rem;
    }
    h2 {
        font-size: 3.5rem;
    }
    h3 {
        font-size: 2rem;
    }
    .testimonial .col:nth-child(3) ,
    .testimonial .col:nth-child(4) {
    margin-top: 4rem;
   }

}