#loading {
    text-align: center;
    position: absolute;
    width: 10px;
    height: 70px;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 1;
    margin: auto;
}
 
#loading p {
    text-align: center;
    font-size: 70px;
}

/* ======================================================1st== */

#pictlist {
    margin: 0 auto;
    overflow: hidden;
    transition: opacity 0.3s;
    opacity: 0;
    max-height: 100vh;
    box-sizing: border-box;
}
 
#pictlist.on {
    opacity: 1;
    max-height: 100%;
}
 
#pictlist li {
    max-width: 300px;
    padding: 5px;
}
 
#pictlist li img {
    max-width: 100%;
    height: auto;
}

/* ======================================================2nd== */

#pictlist2nd {
    margin: 0 auto;
    overflow: hidden;
    transition: opacity 0.3s;
    opacity: 0;
    max-height: 100vh;
    box-sizing: border-box;
}
 
#pictlist2nd.on {
    opacity: 1;
    max-height: 100%;
}
 
#pictlist2nd li {
    max-width: 300px;
    padding: 5px;
}
 
#pictlist2nd li img {
    max-width: 100%;
    height: auto;
}

/* ======================================================3rd== */

#pictlist3rd {
    margin: 0 auto;
    overflow: hidden;
    transition: opacity 0.3s;
    opacity: 0;
    max-height: 100vh;
    box-sizing: border-box;
}
 
#pictlist3rd.on {
    opacity: 1;
    max-height: 100%;
}
 
#pictlist3rd li {
    max-width: 300px;
    padding: 5px;
}
 
#pictlist3rd li img {
    max-width: 100%;
    height: auto;
}

/* ======================================================4th== */

#pictlist4th {
    margin: 0 auto;
    overflow: hidden;
    transition: opacity 0.3s;
    opacity: 0;
    max-height: 100vh;
    box-sizing: border-box;
}
 
#pictlist4th.on {
    opacity: 1;
    max-height: 100%;
}
 
#pictlist4th li {
    max-width: 300px;
    padding: 5px;
}
 
#pictlist4th li img {
    max-width: 100%;
    height: auto;
}