@media (max-width: 767px) {
  :root { --header-height: 64px; }

  .contact-section { grid-template-columns: minmax(0, 1fr); }
  .contact-copy,
  .contact-form { min-width: 0; width: 100%; }
  .contact-details { max-width: 100%; }
  html[lang="zh-Hant"] .contact-section h2 .display-line {
    white-space: normal;
    word-break: normal;
    overflow-wrap: anywhere;
  }

  .site-header { padding-inline: 16px; }
  .brand { position: relative; z-index: calc(var(--layer-menu) + 1); }
  .header-actions { display: contents; }
  .language-switcher-desktop { display: none; }

  .menu-toggle {
    position: relative;
    z-index: calc(var(--layer-menu) + 1);
    min-height: 44px;
    padding: 0;
    display: inline-flex;
    align-items: center;
    border: 0;
    background: transparent;
    cursor: pointer;
    font-size: 11px;
    letter-spacing: .12em;
    text-transform: uppercase;
  }

  .menu-toggle > span { display: none; }

  .menu-toggle i,
  .menu-toggle i::before,
  .menu-toggle i::after {
    width: 24px;
    height: 1px;
    display: block;
    background: currentColor;
    transition: transform .25s ease, background-color .25s ease;
  }
  .menu-toggle i { position: relative; }
  .menu-toggle i::before,
  .menu-toggle i::after { content: ""; position: absolute; left: 0; }
  .menu-toggle i::before { top: -7px; }
  .menu-toggle i::after { top: 7px; }
  .menu-toggle[aria-expanded="true"] i { background: transparent; }
  .menu-toggle[aria-expanded="true"] i::before { transform: translateY(7px) rotate(45deg); }
  .menu-toggle[aria-expanded="true"] i::after { transform: translateY(-7px) rotate(-45deg); }

  .site-header nav {
    position: fixed;
    inset: 0;
    z-index: var(--layer-menu);
    min-height: 100dvh;
    padding: 120px 24px 48px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 24px;
    background: var(--color-bg);
    visibility: hidden;
    opacity: 0;
    pointer-events: none;
    transition: opacity .25s ease, visibility .25s ease;
  }

  .site-header.is-menu-open {
    border-color: transparent;
    background: var(--color-bg);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

  .language-switcher-mobile {
    margin-bottom: 24px;
    display: flex;
    font-size: 12px;
  }
  .language-switcher-mobile button { min-height: 36px; }
  .site-header nav a { font-family: var(--font-display); font-size: clamp(42px, 14vw, 64px); font-weight: 500; letter-spacing: -.05em; line-height: 1; text-transform: uppercase; }
  html[lang="zh-Hant"] .site-header nav a {
    font-family: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", sans-serif;
    font-size: clamp(38px, 12vw, 52px);
    font-weight: 600;
    letter-spacing: 0;
    line-height: 1.18;
  }
  .site-header.is-menu-open nav { visibility: visible; opacity: 1; pointer-events: auto; }
  body.is-menu-open { overflow: hidden; }
}

@media (min-width: 1440px) {
  :root { --content-max: 1360px; }
}