html,
body {
    height: 100%;
    box-sizing: border-box;
    font-size: 16px;
}
body {
    font-family: "Roboto", sans-serif;
    margin: 0;
    position: relative;
}

p, h2 {
    margin: 0;
}

ul {
    padding: 0;
    margin: 0;
    list-style: none;
}

main,
header {
    max-width: 1627px;
    margin: 0 auto;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 30px 15px;
}

.contact-us,
nav a {
    text-transform: uppercase;
    text-decoration: none;
    color: #414042;
    font-size: 16px;
    font-weight: 500;
}

nav a:hover {
    color: #08C4A3;
}

nav a:not(:last-child) {
    margin-right: 20px;
}

.write-to-us,
.contact-us {
    background: #08C4A3;
    border-radius: 8px;
    color: #fff;
    padding: 10px 21px;
}

.write-to-us:hover,
.contact-us:hover {
    filter: brightness(1.1);
}

footer {
    color: #828282;
    text-align: center;
    width: 100%;
    padding: 80px 0 30px;
    box-sizing: border-box;
}

.promo-section {
    display: flex;
    align-items: center;
    margin: 80px 0 0;
}

.text-section {
    margin-left: 35px;
    width: 60%;
}

.text-section h2 {
    font-size: 40px;
    text-transform: uppercase;
    color: #373737;
    margin-bottom: 20px;
}

.text-section-desc {
    color: #414042;
    margin-bottom: 20px;
    line-height: 32px;
    font-size: 20px;

}

.text-section-desc--highlight {
    color: #08C4A3;
    font-size: 18px;
}

.text-section-referance p {
    font-size: 20px;
}

.text-section-ref--highlight {
    color: #08C4A3;
}

.comments-list-title {
    text-transform: uppercase;
    font-weight: bold;
    color: #454545;
    margin-bottom: 15px;
    margin-top: 30px;
}

.comments-list {
    list-style: none;
    margin: 0 0 30px;
    padding: 0;
}

.comments-list li {
    color: #454545;
    background: #DFF7F3;
    padding: 15px;
    border-radius: 4px;
    display: block;
}

.comments-list li:not(:last-child) {
    margin-bottom: 10px;
}

.text-section-referance {
    margin-bottom: 30px;
}

.text-section-referance p {
    margin-bottom: 5px;
}

.write-to-us {
    text-decoration: none;
    padding: 18px 36px;
    font-size: 24px;
    font-weight: 600;
    text-transform: uppercase;
    display: inline-block;
}

.comments-list li b {
    display: block;
    margin-bottom: 10px;
}

@media (max-width: 1700px) {
    .promo-section {
        padding: 0 15px;
    }
}

@media (max-width: 1440px) {
    .promo-section img {
        width: 43%;
        height: 100%;
    }
}

@media (min-width: 1560px) {
    main {
        min-height: 983px;
    }
}

@media (max-width: 1300px) {
    .promo-section {
        justify-content: center;
    }
    .promo-section img {
        width: 40%;
    }
    .text-section {
        max-width: 560px;
        margin-left: 50px;
    }
}

@media (max-width: 870px) {
    .promo-section {
        flex-direction: column;
        align-items: center;
    }
    .text-section {
        margin-left: 0;
        margin-top: 40px;
        text-align: center;
    }
    .promo-section img {
        width: 50%;
    }
}

@media (max-width: 768px) {
    header {
        flex-direction: column;
    }
    nav {
        margin: 15px 0 20px;
    }
    .promo-section img {
        width: 100%;
    }
    footer {
        position: static;
    }
}

@media (max-width: 600px) {
    .promo-section {
        margin-top: 20px;
    }
    .comments-list li {
        display: block;
    }
    .text-section h2 {
        font-size: 28px;
    }
}

@media (max-width: 500px) {
    .text-section-desc {
        font-size: 14px;
    }
}

.text-section-contacts {
    margin-bottom: 10px;
}

.text-section-contacts a {
    color: #08C4A3;
    text-decoration: none;
}

.text-section-contacts a:hover {
    color: #000;
}