html, body {
    margin: 0;
    padding: 0;
    background-color: white;
    color: black;
    font-family: 'Lucida Sans', 'Lucida Sans Regular', 'Lucida Grande', 'Lucida Sans Unicode', Verdana, sans-serif;
    font-size: 1em;
    max-width: 100%;
    overflow-x: hidden;
    position: relative;
    scroll-behavior: smooth;
    background: linear-gradient(90deg, rgb(45, 45, 45) 0%, rgba(15,15,15,1) 40%, rgb(255, 255, 255) 40%);
}
* {
    box-sizing: border-box;
}
a:link, a:visited, a:active {
    color: rgb(90, 90, 200);
}
a:hover {
    color: rgb(180, 170, 170);
}

header {
    background-color: grey;
    padding: 2% 0 2% 2%;
    margin: 5% 0 0 5%;
    position: relative;
}
header h1 {
    margin: 3% 4% 4%;
    color: white;
    text-align: right;
    font-size: 2em;
}

article div.contents {
    padding: 20px;
    color: white;
    background: linear-gradient(90deg, rgba(255,255,255,0) 40%, rgba(15,15,15,1) 40%, rgba(45,45,45,1) 100%);
}
article div.images {
    background: linear-gradient(90deg, rgba(255,255,255,0) 40%, rgba(15,15,15,1) 40%, rgba(45,45,45,1) 100%);
}
article div.images img#img_1 {
    display: block;
    width: 80%;
    margin-left: 5%;
}
article div.images img#img_2 {
    display: block;
    width: 80%;
    margin: 0 auto;
}
article div.contents-reversed {
    background: linear-gradient(90deg, rgba(255, 255, 255, 0) 40%, rgba(15, 15, 15, 1) 40%, 
                                rgba(45, 45, 45, 1) 100%);
    color: white;
    padding: 20px;
    width: 100%;
}
article div.contents-reversed ol {
    list-style-type: decimal-leading-zero;
}
article div.contents-reversed h1 {
    font-size: 2em;
    margin: 0 0 3% 0;
    text-align: center;
}
article div.hr-separator {
    background: linear-gradient(90deg, rgba(255, 255, 255, 0) 40%, rgba(15, 15, 15, 1) 40%, 
                                rgba(45, 45, 45, 1) 100%);
    padding: 3% 20px;
}
article div.hr-separator hr {
    border: 0;
    height: 2px;
    background: linear-gradient(to right, #ccc 0%, #333 40%, #ccc 100%);
}

section#row {
    display: flex;
    flex-wrap: wrap;
}
section div.col-1 {
    flex: 30%;
    padding: 20px;
    left: 10px;
    color: white;
    background: linear-gradient(90deg, rgba(255,255,255,0) 40%, rgba(15,15,15,1) 40%, rgba(45,45,45,1) 100%);
}
section div.col-2 {
    flex: 40%;
    padding: 20px;
    background: linear-gradient(90deg, rgba(255,255,255,0) 40%, rgba(15,15,15,1) 40%, rgba(45,45,45,1) 100%);
}
section div.col-2 img#img_3 {
    width: 100%;
}
section div.col-3 {
    flex: 30%;
    color: white;
    padding: 20px;
    background: linear-gradient(90deg, rgba(255,255,255,0) 40%, rgba(15,15,15,1) 40%, rgba(45,45,45,1) 100%);
}
section#row {
    flex-direction: column;
}

footer {
    color: white;
    background: rgb(10, 10, 10);
    z-index: 1;
    display: flex;
    clear: both;
    background: linear-gradient(180deg, grey 0%, rgba(12,12,12,1) 50%, rgba(20,20,20,1) 100%);
    flex-direction: column;
}
footer a:link, footer a:visited, footer a:active {
    color: white;
}
footer div {
    padding: 5%;
}

footer div.author {
    flex: 40%;
    position: relative;
    width: 100%;
}
footer div.author img {
    float: right;
    border-radius: 4px;
    display: block;
    width: 100%;
    height: auto;
}
footer div.author .text {
    color: #fff;
    font-size: 22px;
    line-height: 1.5em;
    text-shadow: 2px 2px 2px #000;
    text-align: center;
    position: absolute;
    top: 60%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 100%;
}

footer div.links {
    flex: 40%;
}