* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    position: relative;
}

nav {
    width: 100%;
    transition: background-color .6s;
}

.nav-bgshadow {
    background-color: rgba(0, 0, 0, .7);
}

nav .navbar-brand:hover,
nav .nav-link:hover {
    color: #039ddf
}

.nav-link, .navbar-brand {
    text-transform: uppercase;
    color: white;
}

.navbar-nav .nav-link.active {
    color: #039ddf
}

nav .fa-bars {
    color: #039ddf;
    padding: 10px;
}

header {
    color: white;
}

h1 {
    text-transform: uppercase;
    font-weight: 700;
    font-size: 40px;
    text-align: center;
}

header p {
    text-transform: uppercase;
}

.hero-img {
    position: relative;
    height: 100vh;
    background-position: center;
    background-size: cover;
    background-attachment: scroll;
    z-index: -1;
}

header .hero-img {
    background-image: url('/img/2_640.png');
}


.hero-shadow {
    position: absolute;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, .7);
    z-index: -2;
}

.hero-text {
    display: flex;
    justify-content: center;
    align-items: center;
    flex-direction: column;
    height: 100%;
    z-index: 3;
}

#aboutus {
    margin: 10px;
    justify-content: center;
    text-align: justify;
    text-justify: inter-word;

}

#aboutus p {
    color: black;
    margin-top: 20px;
}

#services .hero-img {
    background-image: url('/img/3_320.png');
}

#services, #contact {
    color: white;
}

#contact {
    overflow: hidden;
    text-align: center;
}
#contact a {
    color:white
}
.adress, .mailer {
    z-index: 100;
}

.adress p {
    padding: 0;
}
#contact .hero-img {
    z-index: 1;
    min-height: 100vh;
    background-image: url('/img/4_320.png');
}

.mailer {
    margin: 0 auto;
    text-align: center;
    width: 90%;
    background-color: rgba(0, 0, 0, .4);
    padding: 10px;
    border-radius: 8%;
}

#msg_form > input, #msg_form > textarea, #msg_form > #submitBtn {
    display: block;
    margin-top: 18px;
    width: 100%;
}

#msg_form > #user_mail {
    display: none;
}

.praca {
    margin-top: 30px;
}


@media(min-width: 640px) {
    header .hero-img {
        background-image: url('/img/2_640.png');
        background-attachment: fixed;
    }
    #services .hero-img {
        background-image: url('/img/3_640.png');
        background-attachment: fixed;
    }
    #contact .hero-img {
        background-image: url('/img/4_640.png');
        background-attachment: fixed;
    }
}

@media(min-width: 1024px) {
    header .hero-img {
        background-image: url('/img/2_1024l.png');
    }
    #services .hero-img {
        background-image: url('/img/3_1240.png');
        background-attachment: fixed;
}
    #contact .hero-img {
        background-image: url('/img/4_1024.png');
        background-attachment: fixed;
}

    .container {
        width: 900px;
    }
    #aboutus h1 {
        margin-top: 50px;
    }
    #aboutus .text {
        padding: 0 auto;
        margin-top: 80px;
    }
}

.rotate-center {
	-webkit-animation: rotate-center 0.6s linear infinite both;
	        animation: rotate-center 0.6s linear infinite both;
}