*,
*:after,
*:before {
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box;
    box-sizing: border-box;
}

body,
html {
    font-size: 100%;
    padding: 0;
    margin: 0;
    height: 100%;
}

.clearfix: before,
.clearfix: after {
    content: " ";
    display: table;
}

.clearfix: after {
    clear: both;
}

body {
    background: #999;
    margin: 0;
    padding: 0;
}

.activity {
    pointer-events: none;
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    width: 100vw;
    background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAQAAAAECAYAAACp8Z5+AAAAH0lEQVQYV2NkQAX/GZH4/xkYGBhhAmAOSBJEwDkgAQCCrgQEjpMcPgAAAABJRU5ErkJggg==) repeat;
    z-index: 999;
}

.vignette {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    box-shadow: 0 0 200px rgba(0, 0, 0, .9) inset;
}