* {
    box-sizing: border-box;
    outline: 0
}

a {
    color: inherit
}

body {
    background-color: #1e1e1e;
    color: #fff;
    cursor: default;
    font-family: Helvetica, sans-serif;
    font-size: 16px;
    margin: 0;
    -webkit-tap-highlight-color: transparent
}

header {
    background-color: rgba(255, 255, 255, .1);
    padding: 10px 15px;
    -webkit-user-select: none;
    user-select: none
}

h1 {
    margin: 15px 0
}

main {
    display: block;
    margin: 15px
}

.bg-img {
    background-attachment: fixed;
    background-image: url(https://bing.shangzhenyang.com/api/1080p);
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    -webkit-filter: blur(10px);
    filter: blur(10px);
    height: 100%;
    left: 0;
    opacity: .5;
    position: fixed;
    top: 0;
    transform: scale(1.1);
    width: 100%;
    z-index: -1
}