.eto{
    width: 500px;
    height:100%;
    background-color: rgb(241, 241, 246);
    
    margin: 0 auto;
    display: flex;
    flex-direction: row;
}
main{
    margin: 0 auto;
    text-align: center;
    width: 400px;
    height: 200px;
    background-color: chartreuse;
    margin-bottom: 30px;
    padding: 50px;
}    
h1{
    text-align: center;
    background-color: rgb(251, 37, 59);
    color: #ffffff;
    font-family: Arial, Helvetica, sans-serif;
    height: 50px;
    text-align: center;
    padding: 50px;
    font-weight: 700;
    text-shadow: 3px 3px 6px #000000;
}
nav li {
    display: inline-block;
    justify-content: flex-end;
    background-color: rgb(235, 228, 241);
    
    
   
}
.migi{
    display: flex;
    justify-content: right;
    padding-right: 20px;
   
}

.header_menu  a{
    text-decoration-line: none;         /*アンダーライン消去*/
}
footer{
    text-align: center;
}