/* =============== Reset & Base Style =============== */
* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--text-default);
  font-family: "Noto Sans JP", sans-serif;
  font-size: var(--fontsize-14);
  line-height: var(--lineheight-large);
  letter-spacing: var(--letterspacing-default);
  -webkit-font-smoothing: antialiased;
}

img {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  font: inherit;
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--text-brand);
  outline-offset: 3px;
}

/* =============== Variables (Design Tokens) =============== */
:root {
  /* Semantic Color */
  --text-default: #141414;
  --text-default-light: #434343;
  --text-brand: #00A63C;
  --text-grey: #B8B8B8;
  --border-black: #141414;
  --border-grey: #D0D0D0;
  --border-greylight: #EBEBEB;
  --background-white: #FFFFFF;
  --background-brand: #00A63C;
  --background-black: #141414;
  --background-grey: #B8B8B8;
  --background-greylight: #F7F7F7;
  --btn-main: #141414;
  --base: #ffffff;
  --subtle: #f6f6f6;
  --line: #dedede;

  /* Typography */
  --fontsize-min: 12px;
  --fontsize-14: 14px;
  --fontsize-16: 16px;
  --fontsize-18: 18px;
  --fontsize-20: 20px;
  --fontsize-22: 22px;
  --fontsize-24: 24px;
  --fontsize-28: 28px;
  --fontsize-32: 32px;
  --lineheight-large: 2.6;
  --lineheight-medium: 1.8;
  --lineheight-Small: 1.5;
  --letterspacing-default: 0.08em;

  /* Layout & Gap */
  --gap-none: 0px;
  --gap-2: 2px;
  --gap-4: 4px;
  --gap-8: 8px;
  --gap-12: 12px;
  --gap-16: 16px;
  --gap-24: 24px;
  --gap-32: 32px;
  --gap-48: 48px;
  --gap-64: 64px;
  --gap-80: 80px;
  --gap-140: 140px;
  --page-pad: 64px;
  --max-width: 1020px;
  --header-h: 64px;

  /* Corner Radius */
  --radius-default: 4px;
  --radius-large: 8px;
}

/* =============== Typography =============== */
.h2-title {
  font-weight: bold;
  font-size: var(--fontsize-24);
  color: var(--text-default);
  padding-bottom: var(--gap-16);
  border-bottom: 2px solid var(--border-black);
  margin: 0;
  line-height: var(--lineheight-Small);
}

.h3-title {
  font-weight: bold;
  font-size: var(--fontsize-22);
  color: var(--text-default);
  padding-bottom: var(--gap-8);
  margin: 0;
}

/* =============== Buttons =============== */
.mainbutton {
  font-family: "Inter", sans-serif;
  padding: 12px 16px;
  border: 0;
  border-radius: var(--radius-large);
  background: var(--background-black);
  color: #ffffff;
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: var(--gap-8);
  font-weight: 700;
  letter-spacing: .1em;
  cursor: pointer;
  transition: background-color .3s ease;
}

.mainbutton .arrow {
  display: inline-block;
  width: 20px;
  height: 20px;
  flex-shrink: 0;
  background-image: url("images/arrow-white.svg");
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  transition: transform .3s ease;
  transform: translateX(0);
}

.mainbutton:hover {
  background: var(--background-brand);
}

.mainbutton:hover .arrow {
  transform: translateX(4px);
}

.secondbutton {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: var(--gap-2);
  font-size: var(--fontsize-14);
  font-weight: bold;
}

.secondbutton .square-arrow {
  display: inline-block;
  width: 28px;
  height: 28px;
  background-color: var(--background-greylight);
  background-image: url("images/arrow-brand.svg");
  background-repeat: no-repeat;
  background-position: center;
  background-size: 20px auto;
  border-radius: 4px;
  vertical-align: middle;
  margin-left: 8px;
  transition: transform 0.3s ease, background-color 0.3s ease;
}

.secondbutton:hover,
.secondbutton:focus-visible {
  color: var(--text-brand);
}

.secondbutton:hover .square-arrow,
.secondbutton:focus-visible .square-arrow {
  background-color: var(--background-greylight);
  transform: translateX(4px);
}

.thirdbutton {
  padding: 0 var(--gap-8);
  border-radius: var(--radius-default);
  border: 1px solid var(--border-black);
  color: inherit;
  margin-left: auto;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: var(--gap-2);
  font-size: 10px;
  font-weight: bold;
  transition: opacity 0.3s ease;
}

.thirdbutton .material-symbols-outlined {
  font-size: var(--fontsize-14);
  vertical-align: middle;
}

.thirdbutton:hover,
.thirdbutton:focus-visible {
  opacity: 0.3;
}

/* =============== Header & Navigation =============== */
.site-header {
  position: relative;
  padding: 24px 0;
  margin: 0 var(--page-pad);
  border-bottom: 1px solid var(--border-grey);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: block;
  width: 320px;
}

.logo img {
  display: block;
  width: 100%;
  height: auto;
}

.desktop-nav {
  display: flex;
  align-items: center;
  gap: 40px;
}

.desktop-nav a {
  font-family: "Inter", sans-serif;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: .12em;
}

.desktop-nav a:not(.mainbutton) {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 8px;
  transition: color .3s ease;
}

.desktop-nav a:not(.mainbutton):hover {
  color: var(--text-brand);
}

.menu-button {
  display: none;
}

.mobile-menu {
  display: none;
}

.breadcrumb {
  width: auto;
  margin: 24px var(--page-pad) 0;
  display: flex;
  align-items: center;
  gap: var(--gap-8);
  font-size: var(--fontsize-14);
  font-weight: bold;
  letter-spacing: var(--letterspacing-default);
}

.breadcrumb a {
  transition: color .3s ease;
}

.breadcrumb a:hover {
  color: var(--text-brand);
}

.breadcrumb-home {
  display: inline-flex;
  align-items: center;
  gap: var(--gap-4);
  color: inherit;
  transition: color 0.3s ease;
}

.breadcrumb-home:hover {
  color: var(--text-brand);
}

.separator {
  font-size: 20px;
  color: var(--text-grey);
}

.breadcrumb .current {
  color: var(--text-grey);
  font-weight: 500;
}

/* =============== Footer =============== */
.site-footer {
  background-color: var(--background-white);
  box-shadow: 0 0 24px 0 rgba(0, 0, 0, 0.08);
  padding: 64px 0;
  margin: 0;
  width: 100%;
}

.footer-inner {
  margin: 0 var(--page-pad);
  width: auto;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-brand {
  display: flex;
  justify-content: center;
  align-items: center;
}

.footer-brand a {
  display: inline-flex;
  align-items: center;
  transition: opacity 0.3s ease;
}

.footer-brand a:hover {
  opacity: 0.6;
}

.footer-brand img {
  display: block;
  height: auto;
}

.external-link {
  display: inline-flex;
  align-items: center;
  gap: var(--gap-4);
  font-size: var(--fontsize-min);
  font-weight: bold;
  color: var(--text-default);
  margin-left: auto;
  transition: color 0.3s ease;
}

.external-link:hover {
  color: var(--text-brand);
}

.external-icon {
  font-size: 18px;
  color: var(--text-grey);
  transition: color 0.3s ease;
}

.external-link:hover .external-icon {
  color: var(--text-brand);
}

.footer-divider {
  border: none;
  border-top: 1px solid var(--border-grey);
  margin: 32px 0 40px 0;
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  text-align: left;
}

.footer-address {
  font-style: normal;
  font-size: var(--fontsize-14);
  line-height: var(--lineheight-Small);
  color: var(--text-default-light);
  margin-bottom: var(--gap-24);
}

.footer-bottom .btn-contact {
  margin-bottom: 64px;
}

.copyright {
  font-size: var(--fontsize-min);
  color: var(--text-grey);
  letter-spacing: var(--letterspacing-default);
  margin: 0;
}

/* =============== Home =============== */
.hero {
  max-width: var(--max-width);
  width: calc(100% - (var(--page-pad) * 2));
  margin: var(--gap-140) auto;
}

.hero-lead {
  font-size: var(--fontsize-32);
  font-weight: bold;
  line-height: var(--lineheight-medium);
  letter-spacing: var(--letterspacing-default);
  color: var(--text-default);
  margin: 0;
}

/* =============== Works (Archive) =============== */
.works {
  max-width: var(--max-width);
  width: calc(100% - (var(--page-pad) * 2));
  padding-bottom: var(--gap-140);
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  column-gap: 64px;
  row-gap: 140px;
}

.work-card {
  min-width: 0;
  display: flex;
  flex-direction: column;
}

.work-image-wrap {
  display: block;
  position: relative;
  overflow: hidden;
  border-radius: var(--radius-large);
  border: 1px solid var(--border-grey);
}

.work-image {
  display: block;
  width: 100%;
  height: auto;
  transition: transform 0.3s ease;
}

.work-image-wrap::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(20, 20, 20, 0.2);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: 1;
}

.work-image-wrap .image-secondbutton {
  position: absolute;
  right: 16px;
  bottom: 16px;
  margin: 0;
  color: var(--background-white);
  opacity: 0;
  transform: translateX(0);
  transition: opacity 0.3s ease, transform 0.3s ease, color 0.3s ease;
  z-index: 2;
}

.work-image-wrap:hover::before,
.work-image-wrap:hover .image-secondbutton {
  opacity: 1;
}

.work-image-wrap:hover .work-image {
  transform: scale(1.03);
}

.work-image-wrap:hover .image-secondbutton .square-arrow {
  background-color: var(--background-greylight);
  transform: translateX(4px);
}

.work-body {
  padding: 40px 8px 0;
  display: flex;
  flex-direction: column;
  flex: 1;
}

.work-body .secondbutton {
  margin-top: auto;
  align-self: flex-end;
}

.eyebrow {
  margin: 0 0 12px;
  color: var(--text-grey);
  font-size: 14px;
  font-weight: bold;
  line-height: 1.5;
}

.work-title {
  margin: 0 0 20px;
  font-size: var(--fontsize-20);
  line-height: var(--lineheight-Small);
  letter-spacing: var(--letterspacing-default);
}

.work-description {
  margin: 0 0 32px;
  line-height: var(--lineheight-medium);
  letter-spacing: var(--letterspacing-default);
  flex: 1;
}

.tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--gap-12);
  margin-bottom: var(--gap-24);
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 24px;
  padding: 0 16px;
  border: 1px solid var(--border-grey);
  border-radius: 999px;
  background: var(--background-greylight);
  color: var(--text-default-light);
  font-size: var(--fontsize-min);
  font-weight: bold;
  line-height: 1;
  white-space: nowrap;
}

.works-footer {
  max-width: var(--max-width);
  width: calc(100% - (var(--page-pad) * 2));
  margin: 0 auto var(--gap-140);
  padding-top: 64px;
  border-top: 1px solid var(--border-greylight);
}

/* =============== About =============== */
.about {
  background: var(--subtle);
  padding: 144px var(--page-pad) 176px;
}

.about-inner {
  max-width: var(--max-width);
  margin: 0 auto;
}

.about h2 {
  margin: 0 0 32px;
  font-size: var(--fontsize-28);
  line-height: 1.4;
  letter-spacing: .1em;
}

.about p {
  max-width: 1400px;
  margin: 0 0 32px;
  line-height: 2.4;
}

/* =============== Work Detail (下層ページ) =============== */
h1.page-title-en {
  font-family: 'Inter', sans-serif;
  font-size: var(--fontsize-32);
  font-weight: bold;
  letter-spacing: var(--letterspacing-default);
  line-height: var(--lineheight-medium);
  color: var(--text-default);
  text-align: center;
}

.detail-mv-container {
  width: calc(100% - (var(--page-pad) * 2));
  margin: 48px auto 0;
}

.work-detail {
  max-width: var(--max-width);
  width: calc(100% - (var(--page-pad) * 2));
  margin: 64px auto 144px;
}

.detail-header {
  margin-bottom: 40px;
}

.detail-header .tags {
  margin-bottom: 24px;
}

.detail-eyebrow {
  margin: 0;
  color: var(--text-grey);
  font-size: 14px;
  font-weight: 700;
}

.detail-image-wrap {
  position: relative;
  width: 100%;
  margin: 0 auto;
}

.detail-image {
  width: 100%;
  height: 480px;
  display: block;
  border-radius: var(--radius-default);
  overflow: hidden;
}

.detail-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  display: block;
}

.detail-title {
  position: absolute;
  top: -32px;
  right: 64px;
  margin: 0;
  writing-mode: vertical-rl;
  font-weight: bold;
  font-size: 24px;
  line-height: 1.8;
  letter-spacing: 0.18em;
  color: var(--text-default);
  z-index: 2;
}

.detail-main-layout {
  display: flex;
  justify-content: space-between;
  gap: var(--gap-80);
  width: auto;
  max-width: var(--max-width);
  margin: var(--gap-140) auto;
  padding: 0 var(--page-pad);
  align-items: flex-start;
}

.detail-main-content {
  flex: 1;
  min-width: 0;
}

.detail-meta-section,
.detail-section {
  margin-bottom: 32px;
}

.heading {
  font-weight: bold;
  font-size: var(--fontsize-24);
  color: var(--text-default-light);
  padding-bottom: var(--gap-16);
  border-bottom: 2px solid var(--border-black);
  margin: 0;
}

.detail-description {
  color: var(--text-default-light);
  margin: 0;
  padding: var(--gap-24) 0;
}

.detail-section p {
  margin: 0;
  font-size: var(--fontsize-14);
  line-height: var(--lineheight-large);
  color: var(--text-default-light);
}

/* Local Navigation */
.detail-side-nav {
  width: 220px;
  flex-shrink: 0;
  position: sticky;
  top: var(--gap-64);
}

.sticky-nav-container {
  display: flex;
  flex-direction: column;
  gap: var(--gap-24);
  padding: var(--gap-12) 0;
  border-top: 1px solid var(--border-grey);
  border-bottom: 1px solid var(--border-grey);
}

.side-nav-item-wrap {
  position: relative;
}

.side-nav-item-wrap:not(:last-child)::after {
  content: "";
  position: absolute;
  bottom: -12px;
  left: 0;
  right: 0;
  height: 1px;
  background-color: var(--border-grey);
}

.side-nav-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--gap-12) var(--gap-8);
  border-radius: var(--radius-large);
  color: var(--text-default);
  font-size: var(--fontsize-14);
  font-weight: bold;
  line-height: 1.5;
  transition: background-color 0.2s ease, color 0.2s ease;
  white-space: nowrap;
}

.side-nav-item .square-arrow {
  display: inline-block;
  width: 20px;
  height: 20px;
  background-image: url("images/arrow-brand.svg");
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  vertical-align: middle;
  margin-left: var(--gap-8);
  transform: rotate(90deg);
  flex-shrink: 0;
}

.side-nav-item:hover,
.side-nav-item.is-active {
  background-color: var(--background-greylight);
  color: var(--text-brand);
}

/* Image Grid & Cards */
.image-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--gap-16);
  margin: var(--gap-32) 0;
  width: 100%;
}

.image-grid .full-width,
.grid-text-full {
  grid-column: 1 / -1;
}

.image-item-card {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  width: 100%;
  background-color: var(--background-greylight);
  border-radius: var(--radius-large);
}

.image-item-card:only-of-type,
.image-grid > .image-item-card:first-child:last-child {
  grid-column: 1 / -1;
  width: 100%;
  max-width: none;
}

.item-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gap-16);
  padding: 0 16px 16px;
}

.item-title {
  line-height: 1;
  margin-left: var(--gap-4);
  font-size: var(--fontsize-min);
  color: var(--text-grey);
  letter-spacing: 0.08em;
  word-break: break-all;
}

.item-image-wrap {
  width: calc(100% - 48px);
  margin: var(--gap-24);
  overflow: hidden;
  background-color: var(--background-white);
}

.item-image-wrap img,
.image-item img {
  width: 100%;
  height: auto;
  display: block;
  object-fit: contain;
}

.expand-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--gap-8);
  font-size: var(--fontsize-min);
  font-weight: bold;
  color: var(--text-default);
  cursor: pointer;
}

.expand-badge:hover {
  opacity: 0.8;
  background-color: #FAFAFA;
}

.expand-badge .search-icon {
  font-size: 18px;
}

/* Meta Box & Sub Features */
.detail-meta-box {
  padding: 32px;
  background: var(--subtle);
  border-radius: var(--radius-default);
  margin-bottom: 64px;
}

.detail-meta-box dl {
  margin: 0;
  display: grid;
  gap: 16px;
}

.detail-meta-box div {
  display: flex;
  gap: 24px;
  font-size: 14px;
}

.detail-meta-box dt {
  width: 120px;
  font-weight: 700;
  color: var(--text-default);
  flex-shrink: 0;
}

.detail-meta-box dd {
  margin: 0;
  color: var(--text-default-light);
}

.detail-content h2 {
  font-size: 20px;
  margin: 48px 0 16px;
  color: var(--text-default);
  letter-spacing: .06em;
}

.detail-content h2:first-of-type {
  margin-top: 0;
}

.detail-content p {
  color: var(--text-default-light);
  line-height: 2.2;
  margin: 0 0 32px;
}

.detail-sub-image {
  margin: 48px 0;
  border-radius: var(--radius-default);
  overflow: hidden;
}

.detail-sub-image img {
  width: 100%;
  height: auto;
}

/* Pagination Navigation */
.detail-prev-next-nav {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--gap-48);
  margin-top: var(--gap-140);
  padding: var(--gap-24) 0;
  border-top: 1px solid var(--border-grey);
  border-bottom: 1px solid var(--border-grey);
}

.detail-prev-next-nav::before {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 1px;
  height: calc(100% - 32px);
  background-color: var(--border-grey);
}

.nav-card {
  width: 272px;
  height: 139px;
  flex: 0 0 272px;
  display: flex;
  align-items: center;
  gap: var(--gap-24);
  padding: 16px;
  border-radius: var(--radius-large);
  transition: background-color 0.2s ease;
}

.nav-card-spacer {
  width: 272px;
  height: 139px;
  flex: 0 0 272px;
}

.nav-card:hover {
  background-color: var(--background-greylight);
}

.nav-card .square-arrow {
  display: inline-block;
  width: 20px;
  height: 20px;
  background-image: url("images/arrow-brand.svg");
  background-repeat: no-repeat;
  background-position: center;
  background-size: 20px auto;
  border-radius: 4px;
  vertical-align: middle;
  flex-shrink: 0;
}

.prev-card .square-arrow {
  transform: rotate(180deg);
}

.next-card {
  text-align: left;
}

.card-text {
  flex: 1;
  min-width: 0;
}

.card-title {
  font-size: var(--fontsize-14);
  font-weight: bold;
  line-height: var(--lineheight-Small);
  color: var(--text-default);
  margin: 0;
}

.card-sub {
  font-size: var(--fontsize-min);
  line-height: var(--lineheight-Small);
  color: var(--text-grey);
  margin: var(--gap-8) 0 0 0;
}

.detail-footer-nav {
  margin-top: 96px;
  display: flex;
  justify-content: center;
}

/* =============== Modal (Image Zoom) =============== */
.image-modal {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.image-modal.is-open {
  opacity: 1;
  pointer-events: auto;
}

.modal-overlay {
  position: absolute;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.75);
  backdrop-filter: blur(4px);
}

.modal-content {
  position: relative;
  z-index: 1;
  max-width: 90vw;
  max-height: 85vh;
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-content img {
  max-width: 100%;
  max-height: 85vh;
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: var(--radius-large);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.3);
}

.modal-close {
  position: absolute;
  top: -44px;
  right: 0;
  background: none;
  border: none;
  color: #ffffff;
  font-size: 32px;
  line-height: 1;
  cursor: pointer;
  padding: 4px;
  transition: color 0.2s ease;
}

.modal-close:hover {
  color: var(--text-brand);
}

/* =============== Responsive Styles =============== */

/* Tablet & Mobile (Max-width: 768px) */
@media (max-width: 768px) {

  :root {
  /* Typography */
  --fontsize-min: 12px;
  --fontsize-14: 12px;
  --fontsize-16: 14px;
  --fontsize-18: 16px;
  --fontsize-20: 16px;
  --fontsize-22: 16px;
  --fontsize-24: 18px;
  --fontsize-28: 20px;
  --fontsize-32: 20px;
  --lineheight-large: 2.6;
  --lineheight-medium: 1.8;
  --lineheight-Small: 1.5;
  --letterspacing-default: 0.04em;

  /* Layout & Gap */
  --gap-none: 0px;
  --gap-2: 2px;
  --gap-4: 4px;
  --gap-8: 6px;
  --gap-12: 10px;
  --gap-16: 12px;
  --gap-24: 18px;
  --gap-32: 20px;
  --gap-48: 28px;
  --gap-64: 48px;
  --gap-80: 80px;
  --gap-140: 120px;
  --page-pad: 24px;
  --max-width: 1020px;
  --header-h: 80px;

  /* Corner Radius */
  --radius-default: 4px;
  --radius-large: 8px;
  }

  /* --------------- Header & Navigation --------------- */
  body.is-navigation-open {
    overflow: hidden;
  }

  body.is-navigation-open .site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 30;
    background-color: var(--background-white);
  }

  body.is-navigation-open .menu-button {
    position: fixed;
    top: calc((var(--header-h) - 44px) / 2);
    right: var(--page-pad);
    z-index: 40;
  }

  .site-header {
    position: relative;
    width: 100%;
    height: var(--header-h);
    margin: 0;
    padding: 0 var(--page-pad);
    display: flex;
    align-items: center;
    justify-content: space-between;
    box-sizing: border-box; 
    border-bottom: none;
  }

  .site-header::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: var(--page-pad);
    right: var(--page-pad);
    height: 1px;
    background-color: var(--border-grey);
    pointer-events: none;
  }

  .logo {
    width: 240px;
  }

  .desktop-nav {
    display: none;
  }

  .menu-button {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;
    width: 44px;
    height: 44px;
    padding: 0;
    border: none;
    background: transparent;
    cursor: pointer;
    z-index: 20;
    position: relative;
  }

  .hamburger-line {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--text-default);
    border-radius: 2px;
    transition: transform 0.3s ease, opacity 0.3s ease;
  }

  .menu-button.is-open .hamburger-line:nth-child(1) {
    transform: translateY(8px) rotate(45deg);
  }

  .menu-button.is-open .hamburger-line:nth-child(2) {
    opacity: 0;
  }

  .menu-button.is-open .hamburger-line:nth-child(3) {
    transform: translateY(-8px) rotate(-45deg);
  }

  .mobile-menu {
    display: flex;
    flex-direction: column;
    gap: 0;
    position: fixed;
    top: var(--header-h);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--header-h));
    padding: 40px var(--page-pad);
    background-color: var(--background-white);
    z-index: 15;
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease;
  }

  .mobile-menu.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .mobile-menu a {
    font-size: var(--fontsize-16);
    font-weight: bold;
    letter-spacing: var(--letterspacing-default);
    padding: 24px 0;
    border-bottom: 1px solid var(--border-greylight);
    text-align: center;
  }

  .mobile-menu a:nth-of-type(3) {
    border-bottom: none;
  }

  .mobile-menu .mainbutton {
    position: relative;
    margin-top: 48px;
    justify-content: center;
    border-bottom: none;
    border-top: none;
    padding: 16px;
    width: 100%;
  }

  .mobile-menu .mainbutton .arrow {
    position: absolute;
    right: 20px;
    top: 50%;
    transform: translateY(-50%);
  }

  /* スマホ時：パンくずを1行で横スクロール */
  .breadcrumb {
    width: 100%;
    margin: 16px 0 0;
    padding: 0 var(--page-pad);
    gap: 8px;
    font-size: 12px;
    overflow-x: auto;
    white-space: nowrap;
    -webkit-overflow-scrolling: touch; /* iOSでの滑らかなスクロール */
    scrollbar-width: none; /* Firefoxスクロールバー非表示 */
  }

  .breadcrumb::-webkit-scrollbar {
    display: none; /* Chrome/Safariスクロールバー非表示 */
  }

  .breadcrumb * {
    flex-shrink: 0; /* 子要素が縮まないように設定 */
  }

  .breadcrumb .material-symbols-outlined {
    font-size: 20px;
  }

  /* --------------- Home & Works (Archive) --------------- */
  .hero {
    width: calc(100% - (var(--page-pad) * 2));
    margin: 80px auto 64px;
  }

  .works {
    width: calc(100% - (var(--page-pad) * 2));
    padding: 0 0 64px 0;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 48px;
  }
  
  .work-title br {
    display: none;
  }

  .work-body {
    padding: 24px 0 0 0;
  }

  .works-footer {
    width: calc(100% - (var(--page-pad) * 2));
    margin: 0 auto 80px;
  }

  /* --------------- About --------------- */
  .about {
    padding: 64px var(--page-pad) 80px;
  }

  /* --------------- Work Detail --------------- */
  .detail-mv-container {
    width: 100%;
    padding: 0 var(--page-pad);
    margin: 24px 0 0;
  }

  .detail-image-wrap {
    width: 100%;
    margin: 0;
    display: flex;
    flex-direction: column;
    gap: 0;
  }

  .detail-title {
    order: 1;
    position: static;
    top: auto;
    right: auto;
    bottom: auto;
    left: auto;
    writing-mode: horizontal-tb;
    font-size: var(--fontsize-32);
    line-height: var(--lineheight-medium);
    letter-spacing: var(--letterspacing-default);
    color: var(--text-default);
    background: none;
    padding: 32px 0 24px;
    backdrop-filter: none;
  }

  .detail-image {
    order: 2;
    width: 100%;
    height: auto;
  }

  .detail-image img {
    height: auto;
    object-fit: contain;
  }

  .work-detail {
    width: calc(100% - (var(--page-pad) * 2));
    margin: 32px auto 64px;
  }

  .detail-main-layout {
    flex-direction: column-reverse;
    width: 100%;
    margin: 64px 0 64px;
    padding: 0 var(--page-pad);
    gap: 64px;
  }

  .detail-side-nav {
    width: 100%;
    position: static;
  }

  .detail-meta-box div {
    display: block;
  }

  .detail-meta-box dt {
    margin-bottom: 4px;
  }

  .image-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .image-item-card {
    padding: 0;
  }

  .item-header{
      padding: 0 18px 18px;
  }

  .detail-prev-next-nav {
    flex-direction: column;
    gap: 16px;
    padding: 24px 0;
  }

  .detail-prev-next-nav::before {
    display: none;
  }

  .nav-card {
    width: 100%;
    height: auto;
    flex: 1 1 auto;
    padding: 20px 16px;
  }

  .nav-card-spacer {
    display: none;
  }

  /* --------------- Footer --------------- */
  .site-footer {
    padding: 40px 0 30px;
  }

  .footer-top {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--gap-16);
  }

  .external-link {
    margin-left: 0;
  }
}