.name-viet{
  /* white-space: nowrap; */
      font-size: 20px;
}
.box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe{
  width: 26vw;
  max-width: 380px;
}
.box_3 .last_box iframe{
  width: 27vw;
  max-width: 380px;
}

@media screen and (min-width: 768px) {

}
@media (max-width: 570px){
  .name-viet{
    font-size: 16px;
  }
}
@media (max-width: 1040px){
.first_img{
  margin-top:-1rem;
}
.header_item{
  font-size: 17px;
}
}
@media (min-width: 1400px){
.container-lg, .container-md, .container-sm, .container-xl, .container-xxl {
    max-width: 1441px !important
  }
  .container{
    max-width: 1200px !important
  }
  .col_txt {
    font-size: 17px;
  }
}
/*  devices (large laptops and desktops, 980px ) */

@media screen and (max-width: 1399px) and (min-width: 1351px) {
  .facebook_iframe iframe, .youtube_video iframe{
    width: 34vw;
  }
  .box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe{
    width: 28vw;
  }
  .box_3 .last_box iframe{
    width: 29vw;
  }
}
@media screen and (max-width: 1350px) and (min-width: 1251px) {
  .facebook_iframe iframe, .youtube_video iframe{
    width: 36vw;
  }
  .box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe, .box_3 .last_box iframe{
    width: 26vw;
  }
}
@media screen and (max-width: 1250px) and (min-width: 1151px) {
  .facebook_iframe iframe, .youtube_video iframe{
    width: 40vw;
  }
  .box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe{
    width: 28vw;
  }
  .box_3 .last_box iframe{
    width: 29vw;
  }
}
@media screen and (max-width: 1150px) and (min-width: 992px) {
  .facebook_iframe iframe, .youtube_video iframe{
    width: 43vw;
  }
  .box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe{
    width: 28vw;
  }
  .box_3 .last_box iframe{
    width: 29vw;
  }
}

    /* for footer page */
/* } */

/* for under ipad */
@media screen and (min-width:768px) and (max-width: 850px) {
  .mb-head {
        display: block !important;
    }

    .pc-head {
        display: none;
    }

    /* .lang-btn{
      margin: 0px!important;
      width: 150px;
    } */
    .navbar {
      padding: 1rem 0!important;
    }
    .okayama_ryugaku_bunsyo{
      position: relative;
      margin-top: -4rem;
    }
}

@media screen and (max-width: 768px) {
  .ryugaku{
    display: block;
  }
  .ruins{
    width: 100%;
  }
.topic-1{
  font-size: 28px;
}
.okayama_ryugaku_bunsyo{
 position: relative;
  margin-top: -4rem;
}

.navbar {
  padding: 1rem 0!important;
}
.seminar_intro .content h5{
  font-size: 17px;
}
.describe_semi h5:first-child{
  font-size: 26px!important;
}
}

@media screen and (max-width: 767px) {
    .mb-head {
        display: block !important;
    }
    .pc-head {
        display: none;
    }
    .top-nav-big-tt{
      width: 65%!important;
      justify-content: flex-start!important;
      margin-left: 15px!important;
      grid-column-gap: 10px;
    }
    .lang-btn{
      margin: 0px!important;
      width: 150px;
    }
    .okayama_ryugaku_bunsyo{
      display: block;
      /* border: 4px solid black; */
    }
    .iframe_content{
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
    }
    .iframe_div{
      background: none;
      height: auto!important;
    }
    .iframe_content .triangle_top_left,
    .iframe_content .triangle_top_right,
    .iframe_content .triangle_top_left_border,
    .iframe_content .triangle_top_right_border{
      display: none;
    }
    .facebook_iframe, .youtube_video{
      width: 100%;
      padding: 0!important;
    }
    .youtube_video{
      margin-top: 1.5rem;
    }
    .facebook_iframe iframe, .youtube_video iframe, .box_3 .last_box iframe{
      height: 260px!important;
      width: 84vw!important;
      max-width: 505px!important;
      min-width: 300px!important;
      border: 3px solid #2f2a53!important;
    }
    .box_3 .last_box iframe{
      margin-top: 20px;
    }
    }


/*  devices (large laptops and desktops, 980px ) */


/* for under ipad */

@media screen and (max-width: 768px) {
  .ryugaku{
    display: block;
  }
  .ruins{
    width: 100%;
  }
}


@media screen and (max-width: 767px) {
    .mb-head {
        display: block !important;
    }

    .pc-head {
        display: none;
    }

}

/* end of navigation */
/* .container-md, .container-sm, .container-xl{
  padding-right: var(--bs-gutter-x,0rem);
    padding-left: var(--bs-gutter-x,0rem);
} */
.special_rgt{
margin-right: 15px;
}
.special_lft{
margin-left: 55px;
}


@media only screen and (max-width: 820px) {
  /* .mb_title_item {
      background: red;
  } */
  .okayama_ryugaku{
width: 100%;
  }
  .bubble{
    transform: translate(65%, -35%);
  }
  .special_lft{
    margin-left: 0px;
  }
  .ryugaku{
    display: block;
  }
  .ruins{
  }
  .study_male{
    width: 100%;
  }
  .collage_img{
    display: block;
  }
  .collage_intro{
    display: block;
  }
  .sensei_img{
    display: flex;
    justify-content: space-around;
  }
  .sensei_text{
    width: 100% !important;
    margin-left: 0!important;
  }
  .sensei_name{
    margin-top: 1rem;
    text-align: center;
  }
  .okayama_ryugaku {
      /* margin: 5px; */
      /* border: 4px solid #343a40; */
      float: none;
      width: 100%;
      margin-top: 1rem;
      display: flex;
  }
  .messsage_box {
    width: 25%;
  }
  .bubble {
  width: 20%;
  transform: translate(510px, -55px);
  }
  .gallery{
    width: 31% !important;
  }
  .collage_img .youtube_girl{
    margin-left: 0!important;
  }

}
@media screen and (max-width:820px ) {
  .img-clg{
    height: auto;
  }
  }
@media screen and (max-width:991px ) {
  .bubble {
  width: 20%;
  transform: translate(510px, -55px);
  }
  .gallery{
    width: 31% !important;
  }
  .study_male{
    margin-right: 0px;
    width: -webkit-fill-available;
  }
  .collage_intro_group{
    padding:0px;
  }
  .momotaro{
    width: 100% !important;
  }

  .setohasi_star{
    transform:translate(-19%, 273%);
  }
  .text_okayama{
    margin-top:1rem;

    }

  .iframe_div{
    height: 246px;
  }
  .facebook_iframe iframe, .youtube_video iframe{
    height: 240px;
    width: 42vw;
  }
  .box_3 .facebook_iframe iframe, .box_3 .youtube_video iframe{
    width: 28vw;
  }
  .box_3 .last_box iframe{
    width: 29vw;
  }
  .triangle_top_right {
    border-bottom: 246px solid #fff;
    border-left: 23px solid transparent;
  }
  .triangle_top_right_border{
    border-bottom: 246px solid #2f2a53;
    border-left: 23px solid transparent;
  }
  .iframe_tt_pc h4{
    font-size: 20px;
  }
}
@media (max-width: 477px){
.gallery {
    width: 100% !important;
}
.mb-title{
  font-size: 25px !important;
}
.setohasi_star {
  transform: translate(-258px, 595px)!important;
}
.star_momotaro{
transform: translate(-256px, 10px);
}
.seminar_intro{
  border: none;
}
.describe_semi {
    margin: 0rem;
    width: 100%;
}
.semi_introper{
transform: translate(-14px, 5px);
}
.title_2nd{
  margin-top: 13rem;
}
.title_1{
  padding: 10px;
  margin-bottom: 1rem;
  margin-top: 2rem;
}
.oka_miryoku {
  margin: 2rem 0!important;
}
.joint-img{
  margin-top: 1rem;
}
.messsage_box{
  width: 60%;
}
.okayama_ryugaku_bunsyo{
  margin-top: -2rem;
}
.border_round{
  margin-left: 0rem !important;
}
.oka_miryoku img{
  min-width: 110px!important;
}
.list_link{
  margin: 2rem 0;
}
}
@media (max-width: 767px){
.bubble {
    transform: translate(65%, -35%);
}
.setohasi_star {
    transform: translate(-9%, 218%);
}
.iframe_tt_re{
  display: block;
}
.iframe_tt_pc{
  display: none;
}

}
@media screen and (min-width:820px), screen and (max-device-width: 911px){
/* .special_lft{
  margin-left:39px !important;
  } */
  .special_rgt {
    margin-right: 0px;
}
}
  @media screen and (min-width:913px) and (max-width: 990px) {
  .special_rgt{
  margin-right: 0px;
  }
  .setohasi_star {
    transform: translate(-19%, 273%);
}
  .special_lft{
  margin-left: 35px;
  }
}
@media screen and (max-width:540px){
  .container{
    width: 100%!important;
  }
  .oka_miryoku h5{
    padding: 5px 0;
  }
  .vi_aisatsu .t-name, .vi_aisatsu .t-position{
    font-size: 14px!important;
  }
  .vi_aisatsu .first_tr{
    font-size: 20px!important;
  }
  .img_link{
    margin-top:8px;
    width: 49%;
  }
  .list_link{
    margin-top: 22px;
    flex-wrap: wrap!important;
  }
}
  @media (min-width: 851px){
  .pc-text-img{
    display: none;
  }
  }