@keyframes bg-scrolling-reverse {
    100% { background-position: 50px 50px; }
}
@keyframes bg-scrolling {
    0% { background-position: 50px 50px; }
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes slideIn {
    from { opacity: 0; transform: translateX(-20px); }
    to { opacity: 1; transform: translateX(0); }
}

@font-face {
    font-family: 'Aileron';
    src: url('./fonts/Aileron-Regular.ttf');
}
@font-face {
    font-family: 'Roboto';
    src: url('./fonts/Roboto-Regular.ttf');
}

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

body {
    font-family: 'Roboto', 'Aileron', Helvetica, Arial, sans-serif;
    font-size: 14px;
    font-weight: 700;
    line-height: 1.6;
    background-color: #000;

    margin-top: 5rem;
    text-align: center;
    background: url("./images/tiling.png") repeat 0 0;

    -webkit-animation: bg-scrolling-reverse .92s infinite; /* Safari 4+ */
    -moz-animation:    bg-scrolling-reverse .92s infinite; /* Fx 5+ */
    -o-animation:      bg-scrolling-reverse .92s infinite; /* Opera 12+ */
    animation:         bg-scrolling-reverse .92s infinite; /* IE 10+ */
    -webkit-animation-timing-function: linear;
    -moz-animation-timing-function:    linear;
    -o-animation-timing-function:      linear;
    animation-timing-function:         linear;
}

header {
    position: relative;
    background-color: rgba(16, 16, 16, 0.5);
    padding: 1em;
}

.HeaderBackground {
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    background-image: linear-gradient(135deg, #FF8000, #00AACC);
    opacity: 0.8;
    z-index: -1;
}

nav ul {
    display: flex;
    justify-content: space-around;
    list-style: none;
}

a {
    color: #ff00a0;
    text-decoration: none;
    transition: color 0.3s ease;
}

a:hover {
    color: #60ff00;
}

.Main {
    position: relative;
    width: 100%;
    padding: 2rem;
    background-color: #25252b;
}

section {
    margin-bottom: 2rem;
    color: #00aacc;
}

footer {
    background-color: rgba(16, 16, 16, 0.8);
    color: #fff;
    padding: 2rem;
}

h1 {
    font-family: 'Montserrat', 'Aileron', Helvetica, Arial, sans-serif;
    font-size: 2rem;
    margin-bottom: 1rem;
    opacity: 0;
    animation: fadeIn 1s ease forwards;
}

.Contents {
    color: #ff8000;
    font-family: 'Roboto', 'Aileron', Helvetica, Arial, sans-serif;
    opacity: 0;
    animation: slideIn 1s ease forwards;
}

.About {
    position: relative;
    display: flex;
    justify-content: center;
    height: 256px;
    z-index: 1;
}

.AboutImg {
    position: relative;
    width: 210px;
    height: 210px;
    align-self: center;
}

.Box {
    position: absolute;
    width: 256px;
    height: 256px;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    margin: auto;
    border-radius: 1000px;
    background: repeating-conic-gradient(from var(--a), #ff00a0 0%, #ff00a0 5%, transparent 5%, transparent 40%, #ff00a0 50%);
    animation: animate 4s linear infinite;
    z-index: 0;
}

.Box::before {
    content: '';
    position: absolute;
    left: 0;
    right: 0;
    top: 0;
    bottom: 0;
    border-radius: 1000px;
    background: repeating-conic-gradient(from var(--a), #00aacc 0%, #00aacc 5%, transparent 5%, transparent 40%, #00aacc 50%);
    animation: animate 4s linear infinite;
    animation-delay: -1s;
    z-index: 0;
}

.Box::after {
    content: '';
    position: absolute;
    inset: 8px;
    background: #2d2d39;
    border-radius: 1000px;;
    border: 8px solid #25252b;
    z-index: 0;
}

@property --a {
    syntax: '<angle>';
    inherits: false;
    initial-value: 0deg
}

@keyframes animate {
    0% { --a: 0deg; }
    100% { --a: 360deg; }
}