index.css

body {
    font-family: 'cwTeXYen', sans-serif;
    letter-spacing: 0px;
}

header.masthead {
    position: relative;
    background: url("img/top.jpg") no-repeat center center;
    background-color: #212529;
    -webkit-background-size: cover;
    -moz-background-size: cover;
    -o-background-size: cover;
    background-size: cover;
}

header.masthead .overlay {
    position: absolute;
    background-color: #212529;
    height: 100%;
    width: 100%;
    top: 0;
    left: 0;
    opacity: 0.3;
}

#form-box {
    border-radius: 5px;
    box-shadow: 0px 3px 5px 0px rgba(0, 0, 0, 0.4);
    background-color: #FFFFFFFF;
    /* width: 100px; */
    height: 400px;
    margin: 20px 40px;
}

#content {
    margin-top: 20px;
    color: #333333FF;
    font-weight: 500;
    font-size: 38px;
}

#form-content {
    margin-top: 20px;
}

#text {
    margin-top: 20px;
    color: black;
    font-weight: 500;
    font-size: 18px;
}

#top-text {
    margin-right: 25px;
    margin-bottom: 25px;
    font-weight: 500;
    font-size: 18px;
    color: white;
}

@media (min-width: 768px) {
    header.masthead {
        /* padding-top: 6rem; */
        padding-bottom: 6rem;
    }
}

.showcase .showcase-text {
    padding: 3rem;
}

.showcase .showcase-img {
    min-height: 30rem;
    background-size: cover;
}

@media (min-width: 768px) {
    .showcase .showcase-text {
        padding: 7rem;
    }
}

.testimonials {
    padding-top: 7rem;
    padding-bottom: 7rem;
}

.testimonials .testimonial-item {
    max-width: 18rem;
}

.testimonials .testimonial-item img {
    max-width: 12rem;
    box-shadow: 0px 5px 5px 0px #adb5bd;
}

footer.footer {
    padding-top: 4rem;
    padding-bottom: 4rem;
}