html{
    scroll-behavior: smooth;
}

body{
    background-color: rgba(157, 252, 157, 0.349);
}

.mamu{
    border-bottom: solid 1px ;
    width:400px;
    margin: 1px;  
    color: black;
}
.mamu:hover{
    background-color: rgba(185, 185, 185, 0.308);
}
.url{
    text-decoration:none;
}
.mamu1{
    font-size: 2.5em;
    font-weight: bold;
    
}

.mamu2{
    font-weight: bolder;
    font-size: 1.2em;
}

.kaisaibi{
    font-size: small
}
.yazi{
    list-style: url(yazi.png);
    border-bottom: solid 1px;
    margin-right: 10px;
    padding-bottom: 2em;
}

.sikaku{
    list-style-type: square;
}

.osi{
    font-size: large;
    font-family: 'Courier New', Courier, monospace;
}

.pic {
    /*背景の基点とするためrelativeを指定*/
    position: relative;
    /*ボタンの形状*/
    display: inline-block;
    width:100%;
    max-width: 400px;
    height: 225px;
    line-height: 225px;
    outline: none;
}

.pic img{
    display: block;
    position: absolute;
    width: 100%;
    height: 100%;
    transform-style: preserve-3d;
    
    transition: 1s;
}

.rotatefront img:nth-child(1){
    transform: rotateX(0deg);
    transform-origin: 0 50% 113px;
}
.rotatefront:hover img:nth-child(1){
    transform: rotateX(90deg);
}

.rotatefront img:nth-child(2){
    transform: rotateX(90deg);
    

    transform-origin: 0 50% -113px;
}

.rotatefront:hover img:nth-child(2){
    transform: rotateX(0deg);
    
}
