/* ── THEME TOKENS（アレンジ用：ここを変更すれば配色を一括変更可）── */
  :root {
    --color-bg: #fff;
    --color-text: #000;
    --color-text-strong: #111;
    --color-text-body: #333;
    --color-text-secondary: #555;
    --color-text-tertiary: #666;
    --color-text-muted: #888;
    --color-text-faint-2: #999;
    --color-text-faint: #aaa;
    --color-text-placeholder: #bbb;
    --color-border: #ebebeb;
    --color-border-strong: #ccc;
    --color-border-light: #ddd;
    --color-divider: #f0f0f0;
    --color-divider-alt: #e8e8e8;
    --color-surface: #fafafa;
    --color-surface-alt: #f5f5f5;
    --color-hover: #444;
    --color-error: #c0392b;
    --color-work-bg: #d8d8d8;
    --color-placeholder-1: #d4d4d4;
    --color-placeholder-2: #c8c8c8;
    --color-placeholder-3: #d0d0d0;
    --color-placeholder-4: #cacaca;
    --color-placeholder-5: #dcdcdc;
    --color-placeholder-6: #c4c4c4;
    --font-base: 'Hiragino Kaku Gothic ProN', 'Yu Gothic', 'Hiragino Sans', 'Meiryo', sans-serif;
  }

  * { box-sizing: border-box; margin: 0; padding: 0; }

  /* スクロールバー非表示 */

  /* ── 画像保護（写真配置予定箇所すべて）── */
  img,
  .thumb,
  .about-photo,
  .about-photo *,
  .detail-hero,
  .work-item .thumb,
  .work-item .work-info {
    -webkit-touch-callout: none;
    -webkit-user-drag: none;
    user-drag: none;
    -webkit-user-select: none;
    user-select: none;
    pointer-events: none;
  }

  /* work-item自体はクリック受け付ける */
  .work-item {
    pointer-events: auto;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    user-select: none;
  }
  html {
    scrollbar-width: none;
    color-scheme: light;
    background: var(--color-bg);
  }
  html::-webkit-scrollbar { display: none; }

  body {
    font-family: var(--font-base);
    background: var(--color-bg);
    color: var(--color-text);
    font-size: 14px;
    cursor: default;
  }

  /* ── NAV ── */
  nav {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: 60px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 40px;
    background: var(--color-bg);
    z-index: 100;
  }

  .logo {
    font-size: 15px;
    font-weight: 700;
    letter-spacing: 0.05em;
    color: var(--color-text);
    text-decoration: none;
    cursor: pointer;
    flex-shrink: 0;
    margin-right: 24px;
    white-space: nowrap;
  }

  nav ul { list-style: none; display: flex; flex-wrap: nowrap; }

  nav ul li a {
    display: block;
    font-size: 12px;
    font-weight: 400;
    letter-spacing: 0.08em;
    color: var(--color-text-faint);
    text-decoration: none;
    padding: 0 16px;
    height: 60px;
    line-height: 60px;
    border-bottom: 2px solid transparent;
    transition: color 0.2s, border-color 0.2s;
    white-space: nowrap;
    cursor: pointer;
  }

  nav ul li a:hover { color: var(--color-text); }
  nav ul li a.active { color: var(--color-text); border-bottom-color: var(--color-text); }

  /* ── HAMBURGER (hidden by default) ── */
  .hamburger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px;
    height: 36px;
    cursor: pointer;
    background: none;
    border: none;
    padding: 4px;
    flex-shrink: 0;
    position: relative;
    z-index: 101;
  }
  .hamburger span {
    display: block;
    height: 1.5px;
    background: var(--color-text);
    transition: transform 0.25s, opacity 0.25s;
    transform-origin: center;
  }
  .hamburger.open span:nth-child(1) { transform: translateY(6.5px) rotate(45deg); }
  .hamburger.open span:nth-child(2) { opacity: 0; }
  .hamburger.open span:nth-child(3) { transform: translateY(-6.5px) rotate(-45deg); }

  /* ── STACKED NAV (medium breakpoint) ── */
  nav.stacked {
    height: auto;
    flex-direction: column;
    align-items: stretch;
    padding: 12px 20px 0;
  }

  nav.stacked .logo {
    margin-right: 0;
    margin-bottom: 0;
    padding-bottom: 4px;
  }

  nav.stacked ul {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-around;
    width: 100%;
    margin: 0;
    padding: 0;
  }

  nav.stacked ul li { flex: 1; text-align: center; }

  nav.stacked ul li a {
    height: auto;
    line-height: 1;
    padding: 8px 4px;
    font-size: 12px;
    border-bottom: 2px solid transparent;
    display: block;
    width: 100%;
  }

  nav.stacked ul li a.active { color: var(--color-text); border-bottom-color: var(--color-text); }

  /* ── HAMBURGER NAV (narrow) ── */
  nav.hamburger-mode {
    height: 56px;
    flex-direction: row;
    align-items: center;
    padding: 0 20px;
  }

  nav.hamburger-mode .logo { margin-right: 0; position: relative; z-index: 101; }

  nav.hamburger-mode .hamburger { display: flex; }

  nav.hamburger-mode ul {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: var(--color-bg);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 8px;
    z-index: 99;
  }

  nav.hamburger-mode ul.open { display: flex; }

  nav.hamburger-mode ul li { flex: none; text-align: center; }

  nav.hamburger-mode ul li a {
    display: block;
    height: auto;
    line-height: 1;
    padding: 16px 40px;
    font-size: 16px;
    letter-spacing: 0.15em;
    border-bottom: 2px solid transparent;
    color: var(--color-text-faint);
  }

  nav.hamburger-mode ul li a.active {
    color: var(--color-text);
    border-bottom-color: transparent;
  }

  /* ── MAIN ── */
  main { padding-top: 60px; min-height: 100svh; background: var(--color-bg); }

  .section { display: none; background: var(--color-bg); }
  .section.active { background: var(--color-bg); }
  .section.active { display: block; animation: fadeIn 0.3s ease; }

  @keyframes fadeIn {
    from { opacity: 0; transform: translateY(6px); }
    to   { opacity: 1; transform: translateY(0); }
  }

  /* ── WORKS ── */
  .works-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
    padding: 0 40px;
  }

  .work-item {
    position: relative;
    overflow: hidden;
    cursor: pointer;
    aspect-ratio: 16/9;
    background: var(--color-work-bg);
  }

  .thumb {
    width: 100%;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 11px;
    color: var(--color-text-placeholder);
    letter-spacing: 0.08em;
    transition: transform 0.5s ease;
    background-size: cover;
    background-position: center;
  }

  .work-item:hover .thumb { transform: scale(1.04); }

  .t1 { background-color: var(--color-placeholder-1); }
  .t2 { background-color: var(--color-placeholder-2); }
  .t3 { background-color: var(--color-placeholder-3); }
  .t4 { background-color: var(--color-placeholder-4); }
  .t5 { background-color: var(--color-placeholder-5); }
  .t6 { background-color: var(--color-placeholder-6); }

  .work-info {
    position: absolute;
    bottom: 0; left: 0; right: 0;
    background: rgba(0,0,0,0.55);
    padding: 18px 20px 14px;
    opacity: 0;
    transform: translateY(4px);
    transition: opacity 0.25s, transform 0.25s;
  }

  .work-item:hover .work-info { opacity: 1; transform: translateY(0); }

  /* タッチデバイス（スマホ）はオーバーレイを常時表示 */
  @media (hover: none) {
    .work-info { opacity: 1; transform: translateY(0); }
  }

  .work-info .title { font-size: 13px; font-weight: 700; color: var(--color-bg); }
  .work-info .year  { font-size: 11px; color: rgba(255,255,255,0.55); margin-top: 3px; }

  /* ── DETAIL PAGE ── */
  #detail { display: none; background: var(--color-bg); }
  #detail.active { display: block; animation: fadeIn 0.3s ease; background: var(--color-bg); }

  .detail-hero {
    width: calc(100% - 80px);
    margin: 0 40px;
    aspect-ratio: 16/9;
    background: var(--color-placeholder-3);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    color: var(--color-text-faint);
    letter-spacing: 0.1em;
  }

  .detail-body {
    padding: 28px 40px 80px;
  }

  .detail-title {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 8px;
    letter-spacing: 0.02em;
  }

  .detail-meta {
    font-size: 12px;
    color: var(--color-text-muted);
    letter-spacing: 0.06em;
    margin-bottom: 32px;
  }

  .detail-info {
    max-width: 480px;
  }

  .detail-note {
    font-size: 13px;
    color: var(--color-text-body);
    line-height: 2;
    margin-bottom: 16px;
    letter-spacing: 0.02em;
  }

  .detail-row {
    display: flex;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--color-border);
    font-size: 13px;
  }

  /* label（所在地など）を太字黒、val（大阪府など）を細字灰 */
  .detail-label { font-weight: 700; color: var(--color-text-strong); }
  .detail-val   { color: var(--color-text-muted); font-weight: 400; }

  /* ── PAGE TITLE ── */
  .page-title {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 48px 40px 28px;
    margin-bottom: 40px;
  }

  /* ── ABOUT ── */
  .about-wrap {
    padding: 40px calc(100% / 7) 80px;
    max-width: 100%;
  }

  .about-block {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0 48px;
    padding: 40px 0;
    border-bottom: 1px solid var(--color-border);
  }
  .about-block--last { border-bottom: none; }
  .about-block--no-border { border-bottom: none; padding-bottom: 0; }
  .about-col { min-width: 0; align-self: start; }

  .about-intro-block { padding-bottom: 32px; }
  .about-intro-text {
    font-size: 13px;
    line-height: 2;
    color: var(--color-text-body);
  }

  .about-name {
    font-size: 22px;
    font-weight: 700;
    letter-spacing: 0.04em;
    margin-bottom: 6px;
  }

  .about-section-title {
    font-size: 17px;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: var(--color-text-strong);
    margin-bottom: 12px;
  }

  /* 左右行高さ同期グリッド */
  .about-block--synced {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0 48px;
  }
  .about-col--title {
    padding-bottom: 0;
    align-self: start;
  }
  .about-row {
    display: flex;
    align-items: baseline;
    gap: 12px;
    padding: 9px 0;
    border-bottom: 1px solid var(--color-border);
    font-size: 13px;
    line-height: 1.8;
    color: var(--color-text-body);
  }
  .about-row--last { border-bottom: none; }
  .about-cell--key {
    font-weight: 700;
    color: var(--color-text-strong);
    white-space: nowrap;
    min-width: 52px;
    flex-shrink: 0;
  }
  .about-cell--label { min-width: 52px; }
  .about-val--main {
    display: block;
    font-weight: 400;
  }
  .about-val--sub {
    display: block;
    font-weight: 400;
    font-size: 13px;
    color: var(--color-text-body);
    margin-top: 0;
  }
  .about-cell--val { flex: 1; }

  /* 旧 career-table（名前・自己紹介ブロック用に残す）*/
  .career-table {
    width: 100%;
    border-collapse: collapse;
  }
  .career-table tr { border-bottom: 1px solid var(--color-border); }
  /* .career-table tr:last-child { border-bottom: none; } — 全行にボーダーを入れる */
  .career-table td {
    font-size: 13px;
    padding: 9px 0;
    line-height: 1.8;
    color: var(--color-text-body);
    vertical-align: top;
  }
  .career-table td:first-child {
    font-weight: 700;
    color: var(--color-text-strong);
    white-space: nowrap;
    padding-right: 12px;
    width: 52px;
  }
  .office-label { width: 80px; }
  .text-link { color: inherit; text-decoration: underline; text-underline-offset: 3px; }
  .text-link:hover { opacity: 0.6; }

  /* ── NEWS ── */
  .news-list { list-style: none; padding: 0 calc(100% / 7) 80px; }

  .news-list li {
    display: grid;
    grid-template-columns: 96px 1fr;
    padding: 16px 0;
    border-bottom: 1px solid var(--color-border);
    align-items: baseline;
    gap: 0;
  }

  .news-date  { font-size: 12px; color: var(--color-text-muted); }
  .news-cat   { font-size: 10px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; }
  .news-title { font-size: 13px; line-height: 1.7; }

  /* ── WORKFLOW ── */
  .workflow-list { padding: 0 calc(100% / 7) 80px; max-width: 100%; margin: 0; }

  .wf-item {
    display: grid;
    grid-template-columns: 48px 1fr;
    gap: 24px;
    padding: 28px 0;
    border-bottom: 1px solid var(--color-border);
  }

  .wf-num { font-size: 22px; font-weight: 700; line-height: 1.2; }
  .wf-body h3 { font-size: 14px; font-weight: 700; margin-bottom: 10px; }
  .wf-body p  { font-size: 12px; line-height: 2; color: var(--color-text-secondary); }
  .wf-body p b { color: var(--color-text-strong); font-weight: 700; }

  /* ── CONTACT ── */
  .contact-wrap {
    padding: 48px calc(100% / 7) 80px;
    max-width: 100%;
  }

  .contact-lead {
    font-size: 13px;
    line-height: 2;
    color: var(--color-text-secondary);
    margin-top: 24px;
    margin-bottom: 40px;
  }

  .req { color: var(--color-text-muted); font-size: 11px; }

  .contact-req-note {
    font-size: 11px;
    color: var(--color-text-faint);
    margin-bottom: 32px;
  }

  .contact-form { display: flex; flex-direction: column; gap: 28px; }

  .form-group label {
    display: block;
    font-size: 10px;
    font-weight: 700;
    letter-spacing: 0.18em;
    text-transform: uppercase;
    color: var(--color-text-faint);
    margin-bottom: 8px;
  }

  .form-group input,
  .form-group textarea {
    width: 100%;
    background: var(--color-surface);
    border: 1px solid var(--color-border-light);
    padding: 10px 12px;
    font-family: inherit;
    font-size: 13px;
    color: var(--color-text);
    outline: none;
    transition: border-color 0.2s;
    -webkit-appearance: none;
    border-radius: 0;
  }

  .form-group input::placeholder,
  .form-group textarea::placeholder { color: var(--color-text-placeholder); }

  .form-group input:focus,
  .form-group textarea:focus { border-color: var(--color-text); background: var(--color-bg); }
  .form-group textarea { resize: none; min-height: 120px; overflow: hidden; }

  .btn-send {
    align-self: flex-start;
    background: var(--color-text);
    color: var(--color-bg);
    border: none;
    font-family: inherit;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 14px 36px;
    cursor: pointer;
    transition: background 0.2s, opacity 0.2s;
    -webkit-appearance: none;
    border-radius: 0;
  }
  .btn-send:hover:not([aria-disabled="true"]) { background: var(--color-hover); }
  .btn-send[aria-disabled="true"] { opacity: 0.3; cursor: default; }

  .privacy-check-wrap {
    margin-bottom: -8px;
  }

  .privacy-check-label {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    cursor: pointer;
    font-size: 12px;
    color: var(--color-text-secondary);
    line-height: 1.6;
  }

  .privacy-check-label input[type="checkbox"]:disabled {
    opacity: 0.35;
  }

  .privacy-check-label.is-disabled {
    opacity: 0.5;
  }

  .privacy-check-label input[type="checkbox"] {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    margin-top: 2px;
    cursor: pointer;
    accent-color: var(--color-text);
    border: 1px solid var(--color-border-strong);
    background: var(--color-surface);
  }

  .privacy-note {
    font-size: 11px;
    color: var(--color-text-faint);
    margin-bottom: -8px;
  }
  .privacy-link {
    color: var(--color-text-secondary);
    text-underline-offset: 3px;
    cursor: pointer;
  }
  .privacy-link:hover { color: var(--color-text); }

  .field-error {
    font-size: 11px;
    color: var(--color-error);
    font-weight: 400;
    letter-spacing: 0.03em;
    margin-left: 4px;
  }

  /* ── CONFIRM MODAL BUTTONS ── */
  .confirm-btns {
    display: flex;
    gap: 12px;
  }

  .btn-cancel {
    flex: 1;
    background: var(--color-bg);
    color: var(--color-text);
    border: 1px solid var(--color-border-strong);
    font-family: inherit;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    padding: 14px;
    cursor: pointer;
    transition: background 0.2s, border-color 0.2s;
    border-radius: 0;
  }
  .btn-cancel:hover { background: var(--color-surface-alt); border-color: var(--color-text-faint-2); }

  .btn-confirm {
    flex: 1;
    background: var(--color-text);
    color: var(--color-bg);
    border: none;
    font-family: inherit;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.15em;
    text-transform: uppercase;
    padding: 14px;
    cursor: pointer;
    transition: background 0.2s;
    border-radius: 0;
  }
  .btn-confirm:hover { background: var(--color-hover); }

  /* ── MODAL ── */
  .modal-overlay {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.45);
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    animation: fadeIn 0.2s ease;
  }

  .modal-box {
    background: var(--color-bg);
    max-width: 480px;
    width: 100%;
    padding: 40px 36px 32px;
  }

  .modal-heading {
    font-size: 16px;
    font-weight: 700;
    letter-spacing: 0.06em;
    margin-bottom: 10px;
  }

  .modal-sub {
    font-size: 12px;
    color: var(--color-text-tertiary);
    line-height: 1.8;
    margin-bottom: 28px;
  }

  .modal-body {
    border-top: 1px solid var(--color-divider-alt);
    margin-bottom: 28px;
  }

  .modal-row {
    display: grid;
    grid-template-columns: 108px 1fr;
    gap: 12px;
    padding: 12px 0;
    border-bottom: 1px solid var(--color-divider);
    font-size: 13px;
  }

  .modal-label { color: var(--color-text-faint); font-size: 11px; padding-top: 2px; }
  .modal-val   { color: var(--color-text); word-break: break-all; white-space: pre-wrap; }

  .modal-close {
    display: block;
    width: 100%;
    background: var(--color-text);
    color: var(--color-bg);
    border: none;
    font-family: inherit;
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.2em;
    text-transform: uppercase;
    padding: 14px;
    cursor: pointer;
    transition: background 0.2s;
    border-radius: 0;
  }
  .modal-close:hover { background: var(--color-hover); }

  /* ── Detail: 追記予定 ── */
  .detail-coming {
    font-size: 12px;
    color: var(--color-text-faint);
    letter-spacing: 0.12em;
    padding: 20px 0 16px;
  }

  /* ── WORKFLOW SUB HEADING ── */
  .wf-body h4 {
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.06em;
    color: var(--color-text-secondary);
    margin-top: 20px;
    margin-bottom: 6px;
    padding-left: 8px;
    border-left: 2px solid var(--color-border-strong);
  }

  /* ── DETAIL PHOTO GRID ── */
  .detail-photo-grid {
    padding: 0 40px 80px;
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 6px;
    /* 行の高さを均一に保ちつつ縦横比は維持 */
    grid-auto-rows: 200px;
  }
  .detail-photo-grid img {
    display: block;
    width: 100%;
    height: 100%;
    object-fit: cover;
    cursor: zoom-in;
    transition: opacity 0.2s;
    pointer-events: auto;
    -webkit-user-drag: none;
    user-select: none;
  }
  .detail-photo-grid img:hover { opacity: 0.85; }

  /* ── LIGHTBOX ── */
  #lightbox {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    z-index: 1000;
    align-items: center;
    justify-content: center;
  }
  #lightbox.open { display: flex; }

  .lb-img-wrap {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    height: 100%;
    padding: 60px 80px;
  }
  #lbImg {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
    pointer-events: none;
    user-select: none;
    -webkit-user-drag: none;
  }

  .lb-close,
  .lb-prev,
  .lb-next {
    position: fixed;
    background: none;
    border: none;
    color: var(--color-text-strong);
    cursor: pointer;
    line-height: 1;
    padding: 12px;
    z-index: 1001;
  }
  .lb-close {
    top: 20px; right: 24px;
    font-size: 20px;
  }
  .lb-prev,
  .lb-next {
    top: 50%;
    transform: translateY(-50%);
    font-size: 44px;
    opacity: 0.7;
  }
  .lb-prev:hover,
  .lb-next:hover { opacity: 1; }
  .lb-prev { left: 16px; }
  .lb-next { right: 16px; }

  .lb-counter {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    color: rgba(0,0,0,0.45);
    font-size: 11px;
    letter-spacing: 0.1em;
  }

  /* ── RESPONSIVE ── */
  @media (max-width: 768px) {
    .works-grid { grid-template-columns: 1fr; padding: 0 20px; gap: 10px; }
    .work-item { aspect-ratio: 16/9; }
    .detail-hero { width: calc(100% - 40px); margin: 0 20px; }
    .detail-body { padding: 20px; }
    .detail-title { font-size: 18px; }
    /* about */
    .about-wrap { padding: 24px 20px 60px; }
    .about-block { grid-template-columns: 1fr; padding: 28px 0; }
    .about-block .about-col + .about-col { margin-top: 28px; }
    .about-block--last { border-top: none; }
    .about-block:not(.about-block--synced):has(+ .about-block--last) { border-bottom: none; }

    /* synced ブロック：モバイルで日本語全行 → 英語全行の順に */
    .about-block--synced {
      grid-template-columns: 1fr;
    }
    /* タイトル行：日本語(1番目)を先頭、英語(2番目)を日本語行の後ろへ */
    .about-block--synced .about-col--title:nth-child(1) { order: 0; }
    .about-block--synced .about-col--title:nth-child(2) { order: 2; margin-top: 28px; }
    /* 日本語行(奇数番目 3,5,7…) → order:1、英語行(偶数番目 4,6,8…) → order:3 */
    .about-block--synced .about-row:nth-child(odd)  { order: 1; }
    .about-block--synced .about-row:nth-child(even) { order: 3; }
    /* 英語ブロック先頭行の上の区切り線なし */

    /* photo grid & lightbox */
    .detail-photo-grid { grid-template-columns: repeat(5, 1fr); grid-auto-rows: auto; padding: 0 20px 60px; gap: 6px; margin-top: 0; }
    .detail-photo-grid img { aspect-ratio: 1/1; height: auto; }
    .lb-img-wrap { padding: 60px 48px; }
    .lb-prev { left: 4px; }
    .lb-next { right: 4px; }
    /* other pages */
    .news-list   { padding: 0 20px 60px; }
    .news-list li { grid-template-columns: 84px 1fr; }
    .workflow-list { padding: 0 20px 60px; }
    .contact-wrap { padding: 0 20px 60px; }
  }

  /* ── SCROLL TO TOP ── */
  #scrollTopBtn {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 40px;
    height: 40px;
    padding: 0;
    background: var(--color-bg);
    border: none;
    cursor: pointer;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.3s;
    z-index: 90;
    display: flex;
    align-items: center;
    justify-content: center;
  }
  #scrollTopBtn.visible {
    opacity: 1;
    pointer-events: auto;
  }
  #scrollTopBtn:hover svg rect { stroke: var(--color-text-secondary); }
  #scrollTopBtn:hover svg polyline { stroke: var(--color-text-secondary); }

  @media (max-width: 768px) {
    #scrollTopBtn { bottom: 20px; right: 20px; }
  }
  .wf-preface,
  .wf-postface {
    padding: 32px 0;
    border-bottom: 1px solid var(--color-border);
  }
  .wf-postface {
    border-bottom: none;
    border-top: 1px solid var(--color-border);
  }
  .wf-preface h3,
  .wf-postface h3 {
    font-size: 13px;
    font-weight: 700;
    letter-spacing: 0.04em;
    margin-bottom: 10px;
    color: var(--color-text-strong);
    padding-left: 14px;
    border-left: 2px solid var(--color-text-strong);
  }
  .wf-preface p,
  .wf-postface p {
    font-size: 12px;
    line-height: 2;
    color: var(--color-text-secondary);
    padding-left: 14px;
  }