React_homework/src/Main.css

main {
    font-family: "Helvetica Neue";
    padding-top: 15px;
    padding-bottom: 15px;
    margin-top: 30px;
    margin-bottom: 30px;
    min-width: 1200px;
}

.welcoming-img {
    width: 500px;
}

.intro-img {
    width: 200px;
    padding-left: 15px;
    float: left;
}
.welcoming {
    text-align: center;
}

.intro {
    text-align: center;
}

hr {
    width: 500px;
}

.text {
    display:block;
}

@media (max-width:1200px) {
    main {
        max-width: 970px;
    }
}

@media (max-width:992px) {
    main {
        max-width: 750px;
    }
}

@media (max-width:767px) {
    main {
        max-width: none;
    }
}