html {
    background-color: #1F2937;
    color: white;
    font-family: Roboto, system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
}

body {
    margin: auto auto;
    text-align: center;    
}

/* header */
nav {
    display: flex;
    width: 75%;
    margin: 16px auto;
    padding: auto auto;
    justify-content:space-between;
    align-content: space-between;
}

#logo {
    font-size: 24px;
    color: #F9FAF8;
    padding: 0 361px 0 0;
    margin: 0 0 0 0;
}

/* buttons */
a {
    font-size: 16px;
    font-weight: 500;
}

.menu {
    font-size: 18px;
    font-weight: lighter;
    color: #E5E7EB;
    text-decoration: none;
    position: relative;
}

.btn {
    text-align: center;
    display: inline-block;
    position: relative;
    color: white;
    background-color: #3882F6;
    font-family: 'Roboto', sans-serif;
    font-size: 18px;    
    padding: 8px 0px;
    width: 120px;
    border-radius: 8px;
    text-decoration: none;
}

.button-with-border {
    border: 1px solid white;
}

.menu::before {
    content: '';
    position: absolute;
    bottom: 0;
    right: 0;
    width: 0;
    height: 2px;
    background-color: #3882F6;
    transition: width 0.6s cubic-bezier(0.25, 1, 0.5, 1);
}


@media (hover: hover) and (pointer: fine) {
     .menu:hover::before {
        left: 0;
        right: auto;
        width: 100%;
    }

    .btn:hover {
        box-shadow: 0 8px 16px 0 rgba(191, 227, 241, 0.13), 0 11px 50px 0 rgba(191, 227, 241, 0.13);
    }

    .menu:hover, .btn:hover, .button-with-border:hover, figure:hover {
        
        filter: grayscale(0);
        -webkit-transform:scale(1.05);
        -moz-transform: scale(1.05);
        -o-transform: scale(1.05);
        transform:scale(1.05);
        -webkit-transition: all 100ms ease-in-out;
            -moz-transition: all 100ms ease-in-out;
            -o-transition: all 100ms ease-in-out;
            transition: all 100ms ease-in-out;
            
    }
}

main {
    display: flex;
    justify-content: center;
    margin-top: 100px;  
}

/* first block of text */
.header_text{    
    width: 75%;
	align-items:center;
	display: flex;
	flex-direction: row;
	justify-content:space-between;
    align-content: space-between;
}

#head_main_title {
    width: 438px;
    font-size: 48px;
    line-height: 48px;
    font-weight:bolder;
    color:#F9FAF8;
    margin: 0 0 8px 0;
    padding: 0 0 0 0;
}

.text_area{
    text-align: left;
    display: block;
    flex-direction: column;
    justify-content: space-between;
    align-content: space-between;    
}

#head-secondary-text{
    width: 438px;
    font-size: 18px;
    font-weight: lighter;
    margin: 0 0 8px 0;
    padding: 0 0 0 0;
}

#place-holder-for-image{
    width: 464px;
    height: 230px;
    background-color: gray;   
    display: flex;
    align-items : center;
    justify-content : center;
    font-size: 18px;
    font-weight:300;
}

/* second block of text */
#white_background {
    background-color: white;
    margin-top: 330px;
    width: 100%;
    position: absolute;
    display: block;
}

#information_text {
    font-weight: bolder;
    font-size: 36px;
    color: #1F2937;
    padding-top: 24px;
}

figure {
    width: 110px;
    margin: 0 0 0 0;
}

.place-holder-for-illustration {
    height: 110px; 
    width: 110px; 
    background-color: #fff; 
    border-radius: 10px;
    border: 2px solid #3882F6;
}

.picture-info {
    color: gray;
    font-size: 12px;
    width: 110px;
    height: auto;
    margin-top: 8px;
}

.container { 
    width: 50%;   
    height: auto;
    display: flex;
    flex-direction: row;
    justify-content: space-around;
    align-items:center ;
    margin: auto;
    padding-top: 24px;
    padding-bottom: 80px;
}

/* third block of text */
.gray-box {
    background-color: #E5E7EB;
    width: 100%;
    display: flex;
    flex-direction: column;
}

article {
    width: 46%;
    color: black;
    margin: auto auto;
    
}

#text-article {
    text-align: left;
    font-size: 28px;
    font-style: italic;
    font-weight: 300;
    color: #1F2937;
    padding: 70px 0 0 0;
}

#text-author {
    text-align: right;
    color: #1F2937;
    margin-right: 29%;
    padding-bottom: 70px;;
}

/* fourth block of text */
.call-to-action-box {
    background-color: #3882F6;
    border-radius: 10px;
    width: 64%;
    margin: 60px auto;
    align-items:center;
	display: flex;
	flex-direction: row;
	justify-content:space-around;
    align-content: space-around;
	
}

#text-line{
    text-align: left;
    display: block;
    flex-direction: column;
    justify-content: space-between;
    align-content: space-between;
}

#call-to-action-title {
    font-size: 16px;
    font-weight: 500;
    margin: 0 0 0 0;
    padding-top: 25px;
}

#call-to-action-text {
    font-size: 12px;
    font-weight: 200;
    margin: 0 0 0 0;
    padding-bottom: 25px;
}

/* footer */
#copyright {
    display: flex;
    justify-content: center;    
    padding-top: 960px;
    padding-bottom: 20px;
}