html, body {
    width: 100%;
    height:100%;
}

body {
    margin: 0 auto;
    padding: 0;
    text-align: center;
    font: 20px Helvetica, sans-serif;
    color: #333;
    background: linear-gradient(135deg, #ccdbdc, #9ad1d4, #80ced7, #007ea7);
    background-size: 400% 400%;
    animation: gradient 15s ease infinite;

}
@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}
article {
    display: block;
    text-align: left;
    width: 80%;
    margin: 0 auto;
    padding: 6% 10%;
}
h1 {
    margin: 0;
    padding: 0;
    font-size: 40px;
    line-height: 80px;
}
h2 {
    margin: 0;
    padding: 0;
    font-size: 30px;
    line-height: 60px;
}
a {
    color: #bb0000;
    text-decoration: none;
}
a:hover {
    color: #333;
    text-decoration: none;
}
.marker,
.marker-lkd {
    color: #333;
    transition: all 300ms ease;
}
.marker:hover {
    filter: none;
    color: #bb0000;
}
.marker-lkd:hover {
    filter: none;
    color: #007ebb;
}
#social-icon {
    margin: 0 12px 0 0;
    width: 46px;
    height: auto;
    float: left;
    filter: none;
    -webkit-filter: grayscale(100%);
    -moz-filter: grayscale(100%);
    -ms-filter: grayscale(100%);
    -o-filter: grayscale(100%);
    cursor: pointer;
    transition: all 300ms ease;
    vertical-align: baseline;
}
#social-icon:hover {
    filter: none;
    -webkit-filter: grayscale(0%);
    -moz-filter:    grayscale(0%);
    -ms-filter:     grayscale(0%);
    -o-filter:      grayscale(0%);
}