.sub_content_wrap {
background: #fff;
box-shadow: 0px 0px 20px 0px #ddd;
text-align: center;
padding: 6.24%;
border-radius: 10px;
font-weight: 500;
position: relative;
}
.sub_content_wrap h3 {
   margin-bottom: 30px;
   padding: 5px;
   border-bottom: 2px solid #325E35;
   line-height: 1.5;
   font-size: 24px;
}
.sub_txt_wrap{
   display: flex;
   margin: 0 auto;
   text-align: left;
}
.sub_txt_wrap h4{
   margin-bottom: 10px;
   font-size: 20px;
   line-height: 1.5;
}

.sub_txt_wrap p{
   font-weight: 100;
}

.sub_txt_box{
   flex-direction: column;
   width: 70%;
}
.sub_txt_box p{
   line-height: 1.5;
}
.sub_bookimgbox {
   width: 30%;
   margin-right: 40px;
}
.sub_bookimgbox img {
   box-shadow: 3px 3px 8px 0px #383838;
}
.sub_detailimgbox {
   flex-direction: column;
   margin-top: 20px;
   
}

/* ////////////// 幅 980px〜1280px ////////////// */
@media (min-width: 769px) and (max-width: 1280px) {
   .txt_box_article {
   padding: 5%;
   }
}


/* ////////////// 幅 980px以下〜 ////////////// */
@media only screen and (max-width:979px) {
   .txt_box_article {
   margin: 1em;
   padding: 2em 0.5em;
   }
   .txt_box_article h3 {
   font-size: 18px;
   }
   .sub_txt_wrap{
   flex-direction: column;
   }
   .sub_txt_box{
   width: 100%;
   }
   .sub_bookimgbox {
   margin: 0 auto 20px;
   width: 50%;
   }
}