body {
    font-family: 'Shippori Mincho', 'Yu Mincho', '游明朝', 'Hiragino Mincho ProN', serif;
    font-size: 13px;
    line-height: 1.7;
    letter-spacing: 0.02em;
    margin: 0;
}
body {
    opacity: 0;
    transition: opacity 1s ease-in-out;
}
body.fade-in {
    opacity: 1;
}
#particles-js {
    position: fixed;
    z-index: -1;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}