#mainimage{
height:250px;
box-shadow:0 2px 3px rgba(0,0,0,0.4);
background:url('../images/wataboushi/bg_midashi.jpg') repeat-x top center;
}
#mainimage h3{
padding:80px 0 0 0;
}

.photo{
display:flex;
padding:20px 0 0 0;
flex-wrap:wrap;
list-style:none;
}
.photo li{
width:calc(100% / 3 - 20px);
margin:0 10px 20px;
}
.photo li img{
width:100%;
height:auto;
border-radius:10px;
}