* {
   box-sizing: border-box;
}
body {
   margin: 0;
   padding: 0;
   font-family: "Hiragino Kaku Gothic Pro", "ヒラギノ角ゴ Pro W3", メイリオ, Meiryo, 
   "ＭＳ Ｐゴシック", "Helvetica Neue", Helvetica, Arial, sans-serif;
   background-color: #e6e6e6;
   letter-spacing : 0.2em;
}
header {
   padding: 30px 4% 10px;
   position: fixed;
   z-index: 20;
   top: 0;
   width: 100%;
   background-image: url(sec0-01.JPG);
   display: flex;
   align-items: center;
}
h1 {
   margin: 0; padding: 0;
   font-size: 30px;
}
h3 {
   text-align:left; 
   background-color: #dcdcdc;
}
nav {
   margin: 0 0 0 auto;
}
ul {
   list-style: none;
   margin: 0;
   display: flex;
}
li {
   margin: 0 0 0 15px;
   font-size: 20px;
}
.flexbox{
   width: 100%;
   display:flex;
}
.tbl11 {
   font-size: 13px; 
   width: 60%; 
   height: 35vh; 
   margin: 0 5px;
} 
.img12 {
   width: 30%; 
   height: 35vh; 
   margin: 0 0 0 0;
}
.tbl21{
   font-size: 13px; 
   width: 60%; 
   height: 35vh; 
   margin: 0 5px;
}
.img22{
   border:0; 
   width: 30%; 
   height: 35vh;
}
.img23{
   display: none;
}
.tbl31{
   font-size: 10px; 
   margin: 0 0 0 10px; 
   width: 48%;
   height: 45vh; 
   border-collapse: collapse;
} 
.tbl32{
   font-size: 10px; 
   margin: 0 0 0 0; 
   width: 48%;
   height: 45vh; 
   border-collapse: collapse;
}   
.tbl31 tr td ,.tbl32 tr td {border:1px solid #333;}

@media screen and (max-width:480px) {

 ul {
    list-style: none;
    margin: 0;
    display: flex;
    flex-direction: column;
 }
.flexbox {
width: 100%;
display:flex;
flex-direction: column;
}
.tbl11 {
   font-size: 13px; 
   width: 95%;
   height: 40vh; 
   margin: 0 0 0 10px;
} 
.img12 {
   width: 95%;
   height: 40vh; 
   margin: 0 0 0 10px;
}
.tbl21{
   font-size: 13px; 
   width: 95%;
   height: 40vh; 
   margin: 0 0 0 10px;
}
.img22{
   border:0; 
   width: 95%; 
   height: 40vh;
   margin: 0 0 0 10px;
}
.img23{
   display: block;
   width: 95%;
   height: 40vh;
   margin: 10px 0 0 10px;
}
.tbl31{
   font-size: 10px; 
   margin: 0 0 0 10px; 
   width: 95%; 
   border-collapse: collapse;
} 
.tbl32{
   font-size: 10px; 
   margin: 0 0 0 10px; 
   width: 95%;
   border-collapse: collapse;
}   

}