/* 内覧会ページ全体のBGM操作。ヘッダー内に収め、PASS・動画・ブラウザ下部UIと重ねない。 */
.site-header {
  gap: 18px;
}

.site-header .nav {
  margin-left: auto;
}

.preview-bgm-toggle {
  position: relative;
  z-index: 2;
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.42rem;
  min-width: 102px;
  height: 40px;
  padding: 0 14px 0 10px;
  border: 1px solid rgba(183, 121, 47, 0.34);
  border-radius: 999px;
  background: rgba(57, 37, 26, 0.9);
  color: #fff9ef;
  box-shadow: 0 7px 20px rgba(54, 31, 18, 0.18), inset 0 1px 0 rgba(255, 255, 255, 0.15);
  font: inherit;
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.045em;
  line-height: 1;
  cursor: pointer;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  transition: background-color 0.18s ease, box-shadow 0.18s ease, transform 0.18s ease;
  -webkit-tap-highlight-color: transparent;
}

.preview-bgm-toggle:hover {
  background: rgba(43, 29, 21, 0.98);
  box-shadow: 0 9px 24px rgba(54, 31, 18, 0.23), inset 0 1px 0 rgba(255, 255, 255, 0.17);
}

.preview-bgm-toggle:active {
  transform: scale(0.96);
}

.preview-bgm-toggle:focus-visible {
  outline: 3px solid rgba(237, 170, 46, 0.72);
  outline-offset: 3px;
}

.preview-bgm-toggle.is-on {
  background: linear-gradient(180deg, rgba(177, 112, 25, 0.98), rgba(119, 68, 11, 0.98));
  box-shadow: 0 8px 24px rgba(178, 111, 24, 0.28), inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.preview-bgm-toggle__icon {
  display: grid;
  place-items: center;
  width: 23px;
  height: 23px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.14);
  font-family: system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  font-size: 0.86rem;
  line-height: 1;
}

.preview-bgm-toggle[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
}

@media (max-width: 980px) {
  .site-header {
    gap: 12px;
  }

  .preview-bgm-toggle {
    width: 42px;
    min-width: 42px;
    height: 42px;
    padding: 0;
    border-radius: 50%;
  }

  #previewBgmLabel {
    display: none;
  }

  .preview-bgm-toggle__icon {
    width: auto;
    height: auto;
    background: transparent;
    font-size: 1.08rem;
  }
}

@media (max-width: 720px) {
  .site-header {
    gap: 8px;
    padding-top: 14px;
    padding-bottom: 14px;
  }

  .site-header .brand {
    min-width: 0;
    gap: 8px;
  }

  .site-header .brand-mark {
    width: 42px;
    height: 42px;
    flex-basis: 42px;
  }

  .site-header .brand-text {
    white-space: nowrap;
    font-size: clamp(0.76rem, 3.45vw, 0.92rem);
    letter-spacing: 0.015em;
  }

  .preview-bgm-toggle {
    width: 40px;
    min-width: 40px;
    height: 40px;
    border-color: rgba(183, 121, 47, 0.42);
    box-shadow: 0 5px 16px rgba(54, 31, 18, 0.18);
  }
}

@media (prefers-reduced-motion: reduce) {
  .preview-bgm-toggle {
    transition: none;
  }
}