index.css

* {
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    box-sizing: border-box;
}

:root {
    --blue: #00b0df;
    --blue-dark: #1e293b;
    --spacing: 20px;
}

html, body{
    background-color: var(--blue-dark);
    color: white;
    font-family: system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif, 'Noto Color Emoji';
    height: 100%;
    width: 100%;
}

html {
    display: table;
    margin: auto;
}

body {
    display: table-cell;
    vertical-align: middle;
    text-align: center;
    padding: var(--spacing);
}

img {
    height: 100px;
    width: 100px;
    object-fit: contain;
}

h1, h3, p, div {
    margin: var(--spacing) 0;
}

h3 {
    color: rgba(255,255,255,0.8);
}

p {
    font-weight: normal;
    color: rgba(255,255,255,0.6);
}

a {
    display: inline-block;
    background-color: #39414e;
    text-decoration: none;
    padding: 10px 20px;
    border-radius: 10px;
    font-weight: bold;
    margin: 3px 0;
    transition: 0.2s background-color;
    color: white;
}
a:hover{
    background-color: #536076;
}

svg {
    height: 20px;
    width: 20px;
}

p:last-child {
    & > a {
        text-decoration: none
    }
}

div {
    background-color: rgba(255,255,255,0.2);
    border: 1px solid rgba(255,255,255,0.5);
    padding: var(--spacing);
    border-radius: 3px;
    display: inline-block;
    width: calc(100% - 20px);
    overflow: auto;
}

section {
    padding-top: 20px;
    display: none;
}