html {
    box-sizing: border-box;
    height: 100%;
}

*, *:before, *:after {
    box-sizing: inherit;
}

html, body, .wrapper {
    margin: 0;
    padding: 0;
    width: 100%;
}

body {
    color: #fff;
    background: url(wallpaper.jpg) no-repeat center / cover fixed;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu,
    Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    height: 100%;
}

.wrapper {
    align-items: center;
    background: -moz-radial-gradient(center center, circle cover, transparent, #000);
    background: -ms-radial-gradient(center center, circle cover, transparent, #000);
    background: -webkit-radial-gradient(center center, circle cover, transparent, #000);
    background: radial-gradient(center center, circle cover, transparent, #000);
    display: flex;
    flex-direction: column;
    justify-content: center;
    min-height: 100%;
    padding: 30px 0;
}

.container {
    padding: 10px 20px;
}

.header__title {
    font-size: calc(50px + 16 * (100vw - 320px) / (960 - 320));
    font-weight: normal;
    margin-bottom: 20px;
    text-align: center;
    text-shadow: #000 5px 5px 5px;
}

.header__description {
    text-shadow: #000 1px 1px 5px;
    line-height: 1.7;
    margin-bottom: 40px;
    text-align: center;
}

.main {
    width: 800px;
    text-align: center;
}

@media (max-width: 800px) {
    .main {
        width: 100%;
    }
}

.section {
    margin-top: 40px;
}

.section__header {
    text-shadow: #000 1px 1px 5px;
    font-weight: normal;
}

.play-button {
    display: inline-block;
}

.play-image {
    max-width: 300px;
}

.button {
    width: 100%;
    max-width: 300px;
    margin: 10px 0;
    background: rgb(112, 50, 50);
    border-radius: 3px;
    color: #eee;
    display: inline-block;
    font-size: 20px;
    padding: 15px 25px;
    text-align: left;
    text-decoration: none;
    transition: background 0.3s;
}

.button:hover, .button:focus, .button:active {
    background: rgb(90, 45, 45);
}

.button--nightly {
    background: #333;
}

.button--nightly:hover,
.button--nightly:focus,
.button--nightly:active {
    background: #222;
}

.github {
    transition: opacity 0.3s;
}

.github:hover, .github:focus, .github:active {
    opacity: 0.7;
}

[id$="version"] {
    font-size: small;
}

.footer {
    margin-top: 30px;
    text-align: center;
}

.footer__nav {
    margin-top: 30px;
    list-style: none;
    padding: 0;
}

.footer__item {
    margin-right: 10px;
}

.footer__link {
    color: #eeeeee;
    text-decoration: none;
}
.footer__link:hover {
    text-decoration: underline;
}