html {
    font-size: 100%;
    height: 100%;
    box-sizing: border-box;
}

*,
*::before,
*::after {
    padding: 0;
    margin: 0;
    box-sizing: inherit;
}

.clearfix::after,
.header::after {
    content: '';
    display: table;
    clear: both;
}

body {
    font-size: 1rem;
    font-family: 'Roboto', sans-serif;
    font-weight: 300;
    line-height: 1.375;
    color: #000000;
}

/* main header */

.page__cell {
    max-width: 1200px;
    padding: 0 10px;
    margin: 0 auto;
}

.header {
    border-bottom: 1px solid #cccccc;
    padding: 1.675rem 0;
}

.logo__picture {
    max-width: 100%;
}

.phone-number,
.email-adress {
    text-decoration: none;
}

.phone-number {
    font-weight: 700;
    font-size: 1.525rem;
    color: #000000;
}

.email-adress {
    color: #000000;
}

.header__images {
    float: left;
}

.header__contact {
    float: right;
    text-align: right;
}

/* menu  */

.nav {
    font-size: 1.1875rem;
}

.nav__list {
    margin: 0;
    padding: 0;
    
    display: flex;
    justify-content: space-between;
}

.link {
    color: #000000;
}

.nav__link {
    display: block;
    text-decoration: none;
    padding: 1.3rem;
}

.nav__link:hover {
    color: #f44336;
}

.slider__item {
    padding-top: 33.7%;

    background-size: cover;
    background-position: center center;
    background-repeat: no-repeat;
}

/* slider  */

.slider .owl-dot span {
    background-color: #ffffff;
    border: 1px solid #cccccc;

    width: 1rem;
    height: 1rem;

    display: block;
}

.slider .owl-dot {
    display: inline-block;
}

.owl-dot {
    margin: 0 0.4065rem;
}

.slider .owl-dot.active span,
.slider .owl-dot:hover span {
    background-color: #000000;
    transition: .3s;
}

.slider .owl-dots {
    text-align: center;
    position: absolute;
    bottom: 0.8rem;
    left: 0;
    right: 0;
    
}

/* slider end */

/* about  */

.headline {
    margin: 2.3rem 0;
    text-align: center;
    font-size: 1.75rem;
    font-weight: 400;
}

.about-desc {
    padding-bottom: 1.8rem;
}

/* about end */



/* chapter  */

.grid__item {
    float: left;
    width: 49.15%;
    margin-right: 1.7%;
    margin-bottom: 1.7%;
    position: relative;
}

.grid__item:nth-of-type(2n) {
    margin-right: 0;
}

.grid__overlay {
    overflow: hidden;
    position: absolute;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    background: rgba(0, 0, 0, 0.5);
    transition: 0.2s;
}

.grid__overlay:hover {
    background: rgba(0, 0, 0, 0.8);
    transition: 0.3s;
    cursor: pointer;
}

.grid__pictures {
    max-width: 100%;
    display: block;
}

.grid__link {
    color: #ffffff;
    text-align: center;
    font-size: 1.8rem;
}

.grid__link:hover {
    font-size: 2rem;
}

.grid__text, .icon-circle__picture {
    position: relative;
    top: 50%;
    transform: translateY(-50%);
}

/* chapter end */


.icon-circle {
    display: inline-block;
    width: 6.25rem;
    height: 6.25rem
}

.icon-circle__picture {
    max-width: 100%;

}

.advantage {
    display: flex;
    flex-direction: row;
}

.advantage__item {
    width: 28%;
    text-align: center;
    margin-right: 8%;
}

.advantage__item:nth-of-type(3n) {
    margin-right: 0;
}

.advantage__headline {
    font-size: 1.25rem;
    font-weight: bold;
    margin-bottom: 1rem;
}

.advantage__icon {
    margin-bottom: 1.1rem;
}


.page__row--footer {
    background-color: #595959;
    color: #ffffff;
    margin-top: 4.375rem;
}

.footer__copyright {
    text-align: right;
}

.footer {
    padding: 1.2rem 0;
}


/* media menu  */

.btn-nav {
    border: 0;
    background: none;
    padding: 0.7rem;
    cursor: pointer;
    border-radius: 0.2rem;
}

.btn-nav:hover {
    background: darkgray;
}

.btn-nav__line {
    display: block;
    width: 20px;
    height: 2px;
    border-radius: 1px;
    background-color: #000;
    margin-bottom: 3px;
}

.btn-nav__line:last-child {
    margin-bottom: 0;
}

.nav__btn {
    text-align: right;
    margin: 0.5em 0;
    display: none;
}