.ch_on {
    opacity: 0;
    animation: fadeIn ease-in 1;
    animation-duration: 0.5s;
    animation-fill-mode: forwards;
}

.ch_off {
    display: none;
}

.bt_off {
    visibility: hidden;
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

@keyframes fadeOut {
    from {
        opacity: 1;
    }
    to {
        opacity: 0;
    }
}

body {
    font-size: 13px;
}

.night {
    background-color: black;
    color: white;
}

.night a {
    color: #dd0;
}

.nav_group {
    float: right;
}

.nav_div + * {
    clear: both;
}

p {
    font-family: "Verdana";
    font-weight: 400;
    font-style: normal;
    font-size: 1.3em;
    line-height: 1.25;
}