.mo_step {display: none;}
.mo_btn {display: none;}
footer .left-box .mo_copy {display: none;}
.mo_img {display: none;}

@media screen and (max-width: 1614px){
  header nav ul {gap: 20px;}
  header .hd_btns {gap: 10px;}
  header .hd_btns a {font-size: 15px;}
  header .logo {width: 170px;}

  .visual .kv_ct .txt-box {margin-bottom: 50px;}
  .visual .kv_ct .txt-box .sub {margin-bottom: 20px; font-size: 20px;}
  .visual .kv_ct .txt-box .tit {font-size: 47px;}
  .visual .kv_ct .kv_item ul {margin: 0 -8px;}
  .visual .kv_ct .kv_item ul li {padding: 0 8px;}

  .sec1 {padding: 120px 0; overflow: hidden;}
  .sec1_ct .d-flex {gap: 80px;}
  .sec1_ct .img-box .big_logo {left: -314px; width: 500px;}
  .sec1_ct .img-box .ceo_img {min-width: 300px;}
  .sec1_ct .txt-box .history_tit {margin-bottom: 50px;}
  .sec1_ct .txt-box .history_tit .tit {font-size: 16px;}
  .sec1_ct .txt-box .history_tit .txt {font-size: 30px;}
  .sec1_ct .txt-box .ceo_info .name {font-size: 30px; gap: 10px; margin-bottom: 25px;}
  .sec1_ct .txt-box .ceo_info .name span {font-size: 26px;}

  .certificate_item:before {max-width: 100%; height: 100%; border-radius: 0;}
  .certificate_item ul {gap: 60px;}

  .sec2 {padding: 0 0 120px;}
  .sec2_tit .tit {font-size: 30px;}
  .sec2_ct .img-box {width: 500px;}
  .sec2_ct .img-box .ytb_bg {max-width: 340px;}

  .sec3 .sec3_ct .content_slide {padding: 80px 310px 80px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box {gap: 40px;}
  .content_slide .slide_tit .txt-box .sub {font-size: 18px;}
  .content_slide .slide_tit .txt-box .tit {font-size: 30px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_tit .more_btn {width: 130px; height: 50px; font-size: 15px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main {padding: 50px 120px;}

  .sec3 {padding-bottom: 120px;}
  .tit-box {margin-bottom: 60px !important; word-break: keep-all;}
  .tit-box .sub {font-size: 18px;}
  .tit-box .tit {font-size: 30px;}

  .sec4 {padding-bottom: 120px;}
  .sec4 .link_btns a {gap: 4px; width: 140px; height: 50px; font-size: 15px;}

  .sec5 {padding-bottom: 120px;}
  .sec5 .sec5_ct ul {gap: 16px 0; margin: 0 -8px;}
  .sec5 .sec5_ct ul li {padding: 0 8px;}
  .sec5 .sec5_ct ul li .child-box {height: 210px; padding: 20px;}
  .sec5 .sec5_ct ul li .child-box .tit p {font-size: 18px;}
  .sec5 .sec5_ct ul li .child-box .tit img {width: 30px;}
  
  .sec6_ct {padding: 80px 150px 80px;}

  .sec7 {padding: 120px 0;}
  .sec7 .sec7_ct ul li .child-box {padding: 20px;}
  .sec7 .sec7_ct ul li .child-box .tit p {gap: 8px; font-size: 18px;}
  .sec7 .sec7_ct ul li .child-box .tit p span {font-size: 16px;}
  .sec7 .sec7_ct ul li .child-box .txt {margin-top: 10px; font-size: 16px;}

  .sec_from .sec_from_ct {padding: 80px 150px 80px;}
  .sec_from_ct .d-flex {gap: 30px;}

  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main {padding: 65px 74px;}
  .card_ct .after .txt-box .txt .stamp {gap: 10px;}
  .card_ct .after .txt-box .txt {font-size: 25px;}
  .card_ct .after .txt-box .txt img {width: 45px;}
  .card_ct .after .txt-box .tit2 {height: 50px; font-size: 18px;}
  .card_ct .before .txt-box .tit2 {height: 50px; font-size: 18px;}
  .card_ct .before .txt-box .txt {height: 150px; font-size: 18px;}
  .card_ct .after .txt-box .txt {height: 190px;}
  .sec3 .sec3_ct .content_slide {padding: 80px 130px 80px;}

  .visual_type2 {padding: 0 20px; box-sizing: border-box;}
  .visual_type2 .container {padding: 150px 0 70px !important;}
  .visual_type2 .vst2_img ul {gap: 30px;}
  .visual_type2 .vst2_img ul li {max-width: 315px;}
  .visual_type2 .point_animate {margin-top: 30px;}
  .visual_type2 .vst_txt .tit {max-width: 220px;}
  .visual_type2 .vst_txt .txt {font-size: 30px;}

  .sec1_new {padding: 100px 0;}
  .sec1_new .right-box::before {left: -90px; width: 819px;}

  .sec1_new .right-box ul {width: 477px;}
  .sec1_new .left_box {max-width: 610px;}
  .sec1_new .left_box .left_box_img2 {width: 200px;}
  

  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main {padding: 35px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main .label_t {padding: 5px 10px; margin-bottom: 15px; font-size: 15px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main .tit {font-size: 18px;}

  .new_kv_item {width: calc(100% - 40px);}
}

@media screen and (max-width: 1400px) {
  .container {max-width: 100%; padding: 0 20px !important;}
  .visual .kv_ct .kv_item {max-width: calc(100% - 100px);}

  .sec0_new_ct ul {gap: 10px 0; margin: 0 -7px;}
  .sec0_new_ct ul li {padding: 0 5px;}
  .sec0_new_ct ul li .child-box {height: 70px; padding: 0 20px; border-radius: 15px;}
  .sec0_new_ct ul li .child-box .tit {font-size: 17px;}
  .sec0_new_ct ul li .child-box .icon {width: 37px;}
}

@media screen and (max-width: 1350px) {
  header nav ul {gap: 10px;}
  header .hd_btns {gap: 5px;}
  header .hd_btns a {font-size: 14px;}
  header .hd_btns a img {width: 13px;}

  .ytb_player .vod-box {width: calc(100% - 80px);}

  .new_kv_item {padding: 30px;}
}

@media screen and (max-width: 1200px) {
  header {height: 60px;}
  header.open {background: transparent;}
  header .container {justify-content: space-between;}
  header .logo {position: initial; transform: initial;}
  header .hd_btns {position: fixed; top: auto; bottom: 20px; right: 20px; transform: initial; flex-flow: column;}
  header .hd_btns a {display: flex; align-items: center; justify-content: center; gap: 0; text-indent: -9999px; overflow: hidden; width: 35px; height: auto; aspect-ratio: 1; border-radius: 100%; padding: 0;}
  header .hd_btns a img {width: 20px;}

  .visual {height: calc(100vh - 85px); margin-top: 60px;}
  .visual .kv_ct .txt-box {margin-bottom: 40px;}
  .visual .kv_ct .txt-box .sub {margin-bottom: 15px; font-size: 18px;}
  .visual .kv_ct .txt-box .tit {font-size: 38px;}
  .visual .kv_ct .kv_item ul {margin: 0 -5px;}
  .visual .kv_ct .kv_item ul li {padding: 0 5px;}
  .visual .kv_ct .kv_item ul li .child-box {gap: 8px;}
  .visual .kv_ct .kv_item ul li .child-box .icon {width: 25px;}
  .visual .kv_ct .kv_item ul li .child-box .item_txt p {font-size: 15px;}

  .sec3 .sec3_ct .content_slide {padding: 80px 200px 80px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul {gap: 20px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main {flex-flow: column; gap: 30px; padding: 20px 40px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main .st_box {text-align: center;}
  .content_slide .slide_tit .txt-box .tit {font-size: 24px;}

  .sec4_ct .step_list ul li {margin: 0 !important;}
  .sec4 .link_btns {margin-top: 80px;}

  .sec5 .sec5_ct ul li {width: calc(100% / 2);}

  .sec6_ct {padding: 80px 40px 80px;}

  .sec_from .sec_from_ct {padding: 20px; border-radius: 20px;}
  .input-box {gap: 7px;}
  .input-box .tit {font-size: 16px;}
  .input-box input {height: 45px; font-size: 15px; padding: 0 10px;}
  .input-box select {height: 45px; font-size: 15px; padding: 0 10px; background: url(./../img/tg_icon2.png) no-repeat calc(100% - 10px) 50%; background-size: 20px; background-color: var(--wt);}
  .input-box textarea {height: 150px; font-size: 15px; padding: 10px;}
  .sec_from_ct .d-flex {gap: 10px;}

  .input-box .byte p {font-size: 14px;}
  .input-box .byte .ct {font-size: 14px;}

  .submit-btn {width: 100%; height: 50px; font-size: 16px; margin: 20px 0 0;}

  .visual_type2 .vst2_img ul {gap: 10px;}
  .visual_type2 .vst2_img ul li {max-width: 100%;}
  .visual_type2 .point_animate {gap: 12px; margin-top: 10px;}
  .visual_type2 .vst_txt {margin-top: 37px;}
  .visual_type2 .vst_txt .tit {max-width: 170px;}
  .visual_type2 .vst_txt .txt {font-size: 20px;}
  .visual_type2 .container {padding: 100px 0 50px !important;}

  /* section {padding: 70px 0;} */
  .sec0_new {padding: 70px 0 0;}
  .sec1_new {padding: 70px 0;}
  .sec1_new .tit-box {margin-bottom: 115px;}
  .sec1_new .container {flex-flow: column; gap: 0; align-items: flex-start;}
  .sec1_new .left_box {padding-bottom: 0;}
  .sec1_new .left_box .left_box_img2 {bottom: 0;}
  .sec1_new .right-box::before {display: none;}
  .sec1_new .right-box {width: 100%; padding: 30px 0; border-radius: 20px; background: #f5f5f5;}
  .sec1_new .right-box ul {gap: 37px; margin: 0 auto;}

  .new_kv_item .tit {gap: 5px; font-size: 17px;}
  .new_kv_item .tit img {width: 20px;}
  .new_kv_item .new_box ul {gap: 7px;}
  .new_kv_item .new_box ul li p {padding: 5px 15px; font-size: 15px;}
}

@media screen and (max-width: 1000px) {
  header {z-index: 11;}
  header nav {position: fixed; top: 0; left: -300px; width: 300px; height: 100vh; background: var(--wt); z-index: 9999; transition: all .5s;}
  header.open nav {left: 0;}
  header nav ul {flex-flow: column; gap: 20px; height: 100%;}
  .mo_btn {display: block; width: 30px;}
  header .logo {width: 139px;}
  
  .visual .kv_ct .txt-box {margin-bottom: 30px;}
  .visual .kv_ct .txt-box .sub {margin-bottom: 10px; font-size: 16px;}
  .visual .kv_ct .txt-box .tit {font-size: 30px;}
  .scroll_down p {font-size: 15px;}
  .scroll_down p img {width: 20px;}

  .sec1 {padding: 70px 0;}
  .sec1_ct .d-flex {gap: 40px;}
  .sec1_ct .img-box .ceo_img {min-width: 250px;}
  .sec1_ct .txt-box .history_tit {margin-bottom: 30px;}
  .sec1_ct .txt-box .history_tit .tit {font-size: 15px;}
  .sec1_ct .txt-box .history_tit .txt {font-size: 20px;}
  .sec1_ct .txt-box .ceo_info .name {font-size: 22px; margin-bottom: 10px;}
  .sec1_ct .txt-box .ceo_info .name span {font-size: 18px;}
  .sec1_ct .txt-box .ceo_info .dl-box {gap: 5px;}
  .sec1_ct .txt-box .ceo_info .dl-box dl {gap: 4px;}
  .sec1_ct .txt-box .ceo_info .dl-box dl dd {font-size: 16px;}
  .sec1_ct .img-box .big_logo {left: 75px;}
  .certificate_item ul {gap: 20px;}

  .sec2 {padding: 0 0 70px;}
  .sec2_tit .tit {font-size: 25px;}
  .sec2_ct .sec2_item {padding: 20px;}
  .sec2_ct .sec2_item .item_tit .tit {padding: 5px 10px; font-size: 15px;}
  .sec2_ct .sec2_item .item_tit .link_btn {font-size: 15px;}
  .sec2_ct .sec2_item .item_tit .link_btn img {width: 16px;}
  .sec2_ct .sec2_item ul {gap: 8px;}
  .sec2_ct .sec2_item .d-flex {margin-top: 15px;}
  .sec2_ct .sec2_item .d-flex .name_box .name {font-size: 15px;}

  .sec3 {padding-bottom: 70px;}
  .sec3 .sec3_ct .content_slide {padding: 20px; border-radius: 20px;}
  .content_slide .slide_tit .txt-box .sub {margin-bottom: 5px; font-size: 16px;}
  .content_slide .slide_tit .txt-box .tit {font-size: 18px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_tit .more_btn {width: 125px; height: 45px; font-size: 15px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main {padding: 20px; border-radius: 20px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main .label_t {margin-bottom: 10px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box .slide_main .tit {margin-bottom: 20px; font-size: 18px;}
  .selector ul:after {margin: 0 7px;}
  #arrows {gap: 10px; margin-top: 20px;}
  #arrows .slick-arrow {width: 15px;}
  .selector ul li button,.selector .dots_len {font-size: 14px;}

  .selector2 ul:after {margin: 0 7px;}
  #arrows2 {gap: 10px; margin-top: 20px;}
  #arrows2 .slick-arrow {width: 15px;}
  .selector2 ul li button,.selector .dots_len {font-size: 14px;}

  .tit-box .sub {font-size: 16px;}
  .tit-box .tit {font-size: 22px;}

  .sec5 {padding-bottom: 70px;}

  .sec4 {padding-bottom: 70px;}
  .sec4 .link_btns {margin-top: 60px;}
  .sec4 .link_btns a {gap: 4px; width: 110px; height: 40px; font-size: 14px;}
  .sec4 .link_btns a img {width: 15px;}

  .sec6_ct {padding: 20px; border-radius: 20px;}
  .talk_slide .talk_slide_ul .slick-list {margin: 0 -5px;}
  .talk_slide .talk_slide_ul .slick-list li {margin: 0 5px;}

  .sec7 {padding: 70px 0;}
  .sec7 .tit-box {margin-bottom: 30px;}
  .sec7 .sec7_ct ul li .child-box {padding: 20px 15px;}
  .sec7 .sec7_ct ul li .child-box .tit p {gap: 4px; font-size: 15px; white-space: initial;}
  .sec7 .sec7_ct ul li .child-box .tit p span {font-size: 15px;}
  .sec7 .sec7_ct ul li .child-box .tit img {width: 17px;}
  .sec7 .sec7_ct ul li .child-box .txt {margin-top: 5px; font-size: 14px;}

  .sec_from .tit-box {margin-bottom: 30px;}
  .sec_from_ct .d-flex {flex-flow: column;}
  .submit-btn {height: 45px; font-size: 15px; margin: 20px 0 0;}

  footer .container {flex-flow: column;}
  footer .left-box {padding-right: 0; margin-right: 0; border-right: 0;}
  footer .left-box .address {margin-bottom: 30px;}
  footer .left-box .logo_box {flex-flow: column; gap: 10px; align-items: flex-start; margin-bottom: 30px;}
  footer .left-box .logo_box .logo {width: 139px;}
  footer .left-box .sns_link {gap: 5px;}
  footer .left-box .sns_link a {width: 25px;}
  footer .left-box .copyright {font-size: 12px; margin-bottom: 50px;}
  footer .copyright.pc_copy {display: none;}
  footer .copyright.mo_copy {display: block; margin-top: 20px; font-size: 12px;}
  footer .right-box .map_area {gap: 10px;}
  footer .right-box .map_area .map_tit {flex-flow: column; align-items: flex-start; gap: 5px;}
  footer .right-box .map_area .map_tit .tit {font-size: 16px;}
  footer .right-box .map_area .map_tit .tit img {width: 15px;}
  footer .right-box .map_area .map_tit .map_address {font-size: 15px;}

  .sec3 {overflow: hidden;}
  .sec3 .tit-img {margin-bottom: 0;}
  .sec3 .container {overflow: hidden;}
  .ytb_player .vod-box {width: calc(100% - 40px);}

  .new_kv_item {flex-flow: column; gap: 10px; padding: 20px;}
  .new_kv_item .new_box ul {flex-wrap: wrap; justify-content: center;}
  .new_kv_item .tit {word-break: keep-all;}

  .sec0_new_ct ul li .child-box .tit {font-size: 15px;}
  .sec0_new_ct ul li .child-box .icon {min-width: 30px; width: 30px;}
}

@media screen and (max-width: 730px) {
  .sec5 .sec5_ct ul li .child-box {height: 165px;}
  .sec5 .sec5_ct ul li .child-box .tit p {font-size: 16px;}
  .sec5 .sec5_ct ul li .child-box .tit img {width: 25px;}
  .sec5 .sec5_ct ul li .child-box .txt_box .txt br {display: none;}
  .mo_btn {width: 20px;}

  .visual .kv_ct .kv_item ul {flex-wrap: wrap; gap: 5px;}
  .visual .kv_ct .kv_item ul li {width: 100%;}
  .visual .kv_ct .kv_item ul li .child-box {height: auto; padding: 20px; box-sizing: border-box;}

  .sec1_ct .d-flex {flex-flow: column-reverse;}
  .sec1_ct .img-box .ceo_img {min-width: auto; width: 150px;}
  .sec1_ct .img-box .big_logo {left: -27px; width: 300px;}
  .sec1_ct .txt-box .history_tit {margin-bottom: 20px;}
  .sec1_ct .txt-box .history_tit .txt {font-size: 18px;}
  .sec1_ct .txt-box .ceo_info .name {gap: 5px; margin-bottom: 5px; font-size: 18px;}
  .sec1_ct .txt-box .ceo_info .name span {font-size: 15px;}
  .sec1_ct .txt-box .ceo_info .dl-box dl dt span {width: 22px; font-weight: 12px;}
  .sec1_ct .txt-box .ceo_info .dl-box dl dd {font-size: 14px;}

  .certificate_item ul {gap: 5px;}

  .sec2 {overflow: hidden;}
  .sec2_ct .img-box {width: calc(100% - 80px);}
  .sec2_ct .img-box .ytb_bg {max-width: 240px;}
  .sec2_ct .sec2_item ul {flex-wrap: wrap; gap: 5px 0; margin: 0 -5px;}
  .sec2_ct .sec2_item ul li {width: calc(100% / 2); padding: 0 5px; box-sizing: border-box;}
  .sec2_ct .sec2_item .item_tit .link_btn {text-indent: -9999px; overflow: hidden;}
  .sec2_ct .sec2_item .d-flex {flex-flow: column;}
  .sec2_ct .sec2_item .d-flex .name_box {flex-flow: column;}

  footer .right-box .map_area .map {border-radius: 10px; aspect-ratio: 600 / 375;}

  .card_ct {flex-flow: column-reverse; width: 100%;}
  .card_ct .after {width: 100%;}
  .card_ct .before {width: calc(100% - 72px);}
  .card_ct .after:before {top: auto; bottom: -36px; left: 0; width: 36px; height: auto; aspect-ratio: 36/40; background: url(./../img/before_icon2.png)no-repeat 50% 50%; background-size: cover;}
  .card_ct .after:after {bottom: -36px; left: auto; right: 0; width: 36px; height: auto; aspect-ratio: 36/40; background: url(./../img/after_icon2.png)no-repeat 50% 50%; background-size: cover;}
  .card_ct .before .txt-box .txt {height: 120px; font-size: 15px;}
  .card_ct .after .txt-box .txt {height: 160px; font-size: 20px;}
  .card_ct .after .txt-box .txt img {width: 30px;}

  .sec1_new .left_box {max-width: 370px;}
  .sec1_new .left_box .left_box_img2 {width: 137px;}

  .visual_type2 .container {border-radius: 20px;}

  .content_slide .slide_tit {flex-flow: column; align-items: flex-start; gap: 10px;}
  .content_slide .slide_tit .more_btn {width: 147px; height: 45px; font-size: 15px;}

  .sec0_new_ct ul li {width: calc(100% / 1); word-break: keep-all;}
  .sec0_new_ct ul li .child-box {justify-content: center; gap: 10px !important;}
}

@media screen and (max-width: 530px) {
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li.slick-active .child-box .slide_tit {flex-flow: column; align-items: flex-start; gap: 10px;}
  .sec3 .sec3_ct .content_slide ul.content_slide_ul li .child-box {gap: 20px;}
  .content_slide .slide_tit .txt-box .tit {font-size: 16px;}
  .content_slide .slide_tit .txt-box .sub {font-size: 15px;}
  .mo_step {display: block;}
  .pc_step {display: none;}

  .sec4 .link_btns {gap: 5px;}

  .tit-box .tit {font-size: 20px; word-break: keep-all;}

  .sec5 .sec5_ct ul li {width: calc(100% / 1);}
  .sec5 .sec5_ct ul li .child-box {min-height: 165px; height: auto;}

  .visual {height: calc(100vh - 75px);}
  .visual .kv_ct .txt-box .sub {font-size: 15px;}
  .visual .kv_ct .txt-box .tit {font-size: 22px;}
  .visual .kv_ct .kv_item ul li .child-box {padding: 10px;}
  .scroll_down {bottom: 30px;}

  .certificate_item ul {flex-wrap: wrap; gap: 20px 0; margin: 0 -2.5px;}
  .certificate_item ul li {width: calc(100% / 2); padding: 0 2.5px; box-sizing: border-box;}

  .sec2_ct .img-box {width: 350px; margin: 0 auto -145px;;}

  .visual_type2 .vst2_img ul {flex-flow: column;}
  .visual_type2 .vst2_img ul li {max-width: 300px;}

  .sec1_new .right-box {padding: 20px; box-sizing: border-box;}
  .sec1_new .right-box ul {width: 100%; gap: 10px;}

  .mo_img {display: block;}
  .pc_img {display: none;}
  .pc_btn_link {top: auto; bottom: 0; right: auto; left: 0; transform: initial; width: 100%;}
  .pc_btn_link ul {flex-flow: row; gap: 0;}
}

@media screen and (max-width: 430px) {
  .sec2_ct .sec2_item ul li {width: calc(100% / 1);}
  
  .sec_from_ct form {gap: 10px;}
  .input-box .tit {font-size: 15px;}
  .input-box input {height: 40px;}
  .submit-btn {height: 40px;}
  .tit-box .tit br {display: none;}
  .sec1_new .tit-box .tit br {display: block;}

  footer .left-box .address dl {flex-flow: column;}

  .card_ct .after:after {bottom: -22px; width: 20px; aspect-ratio: 36/40;}
  .card_ct .before {width: calc(100% - 40px);}
  .card_ct .before .txt-box {word-break: keep-all;}
  .card_ct .before .txt-box .txt {padding: 0 5px; box-sizing: border-box;}
  .card_ct .after .txt-box .txt {word-break: keep-all;}
  .card_ct .before .txt-box .txt br {display: none;}
  .card_ct .after:before {bottom: -22px; width: 20px; aspect-ratio: 36/40;}

  .sec1_new .left_box {width: 100%;}
  .sec1_new .left_box .left_box_img2 {width: 100px;}

  header .hd_btns .pc_tel{display: none;}
  header .hd_btns .mo_tel{display: flex;}
}

@media screen and (max-width: 370px) {
  .sec1_ct .txt-box .history_tit .txt {font-size: 15px;}
  .tit-box .sub {font-size: 15px;}
  .tit-box .tit {font-size: 17px;}

  .sec2_ct .img-box {width: 300px;}
}

@media screen and (max-width: 340px) {
  header nav {width: 280px;}
}