.fitmerge-host { width: 100%; }
    .fitmerge-host .merge-card {
      background: #fff;
      border: 1px solid var(--ys-line);
      border-radius: 14px;
      padding: 26px 28px;
      box-shadow: 0 4px 18px rgba(47, 45, 86, 0.07);
    }
    .fitmerge-host .merge-section {
      margin-top: 24px;
    }
    .fitmerge-host .merge-section:first-child {
      margin-top: 0;
    }
    .fitmerge-host .merge-section-title {
      font-family: var(--ys-font-display);
      letter-spacing: 0.08em;
      text-transform: uppercase;
      font-size: 0.78rem;
      color: var(--ys-navy);
      margin: 0 0 10px;
    }
    .fitmerge-host .merge-section-help {
      font-size: 0.88rem;
      color: var(--ys-muted);
      margin: 0 0 12px;
    }

    /* Drop zone */
    .fitmerge-host .merge-drop-zone {
      border: 2px dashed var(--ys-line);
      border-radius: 12px;
      padding: 28px 22px;
      text-align: center;
      background: var(--ys-bg-soft);
      cursor: pointer;
      transition: border-color 0.15s ease, background 0.15s ease;
    }
    .fitmerge-host .merge-drop-zone:hover,
    .fitmerge-host .merge-drop-zone.merge-drop-active {
      border-color: var(--wf-coral);
      background: rgba(250, 119, 60, 0.06);
    }
    .fitmerge-host .merge-drop-zone p {
      margin: 4px 0;
      color: var(--ys-muted);
      font-size: 0.92rem;
    }
    .fitmerge-host .merge-drop-zone strong {
      color: var(--ys-navy);
      font-size: 1.02rem;
    }
    .fitmerge-host .merge-drop-zone input[type="file"] {
      display: none;
    }
    .fitmerge-host .merge-drop-label {
      display: inline-block;
      margin-top: 8px;
      padding: 8px 16px;
      background: var(--ys-navy);
      color: #fff;
      border-radius: 999px;
      font-family: var(--ys-font-display);
      letter-spacing: 0.06em;
      font-size: 0.82rem;
      cursor: pointer;
    }
    .fitmerge-host .merge-drop-label:hover {
      background: var(--wf-coral);
    }
    .fitmerge-host .merge-status {
      margin-top: 10px;
      font-size: 0.88rem;
      color: var(--ys-muted);
      font-style: italic;
      text-align: center;
    }

    /* File list */
    .fitmerge-host .merge-empty {
      color: var(--ys-muted);
      font-size: 0.92rem;
      font-style: italic;
      margin: 0;
      padding: 14px 0;
      text-align: center;
    }
    .fitmerge-host .merge-file-row {
      display: grid;
      grid-template-columns: 32px 1fr auto;
      gap: 12px;
      align-items: center;
      padding: 12px 14px;
      background: #fff;
      border: 1px solid var(--ys-line);
      border-radius: 10px;
      margin: 6px 0;
      transition: border-color 0.15s ease;
    }
    .fitmerge-host .merge-file-row.has-error {
      border-color: #c69b1a;
      background: #fdf6e0;
    }
    .fitmerge-host .merge-file-idx {
      font-family: var(--ys-font-display);
      font-weight: 700;
      color: var(--wf-coral);
      font-size: 1.1rem;
      text-align: center;
    }
    .fitmerge-host .merge-file-info {
      min-width: 0;
    }
    .fitmerge-host .merge-file-name {
      font-weight: 600;
      color: var(--ys-navy);
      margin-bottom: 4px;
      word-break: break-all;
    }
    .fitmerge-host .merge-sport {
      display: inline-block;
      margin-left: 8px;
      padding: 1px 8px;
      border-radius: 999px;
      background: var(--ys-bg-soft);
      color: var(--ys-muted);
      font-size: 0.74rem;
      font-family: var(--ys-font-display);
      letter-spacing: 0.06em;
      text-transform: uppercase;
      vertical-align: middle;
    }
    .fitmerge-host .merge-file-meta {
      font-size: 0.82rem;
      color: var(--ys-muted);
      display: flex;
      gap: 14px;
      flex-wrap: wrap;
    }
    .fitmerge-host .merge-file-meta strong {
      color: var(--ys-navy);
      font-weight: 600;
      margin-right: 4px;
    }
    .fitmerge-host .merge-file-error {
      margin-top: 6px;
      color: #a07712;
      font-size: 0.84rem;
    }
    .fitmerge-host .merge-file-actions {
      display: flex;
      gap: 4px;
    }
    .fitmerge-host .merge-btn-icon {
      width: 30px;
      height: 30px;
      border: 1px solid var(--ys-line);
      background: #fff;
      border-radius: 6px;
      cursor: pointer;
      color: var(--ys-navy);
      font-size: 0.78rem;
    }
    .fitmerge-host .merge-btn-icon:hover {
      border-color: var(--wf-coral);
      color: var(--wf-coral);
    }
    .fitmerge-host .merge-btn-remove {
      color: #c93939;
    }
    .fitmerge-host .merge-btn-remove:hover {
      border-color: #c93939;
      color: #c93939;
    }
    .fitmerge-host .merge-gap {
      font-size: 0.82rem;
      text-align: center;
      padding: 4px 0;
      color: var(--ys-muted);
    }
    .fitmerge-host .merge-gap.merge-gap-warn {
      color: #c93939;
    }
    .fitmerge-host .merge-gap strong {
      font-family: var(--ys-font-display);
    }

    /* Gap mode */
    .fitmerge-host .merge-radio-group {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
    }
    @media (max-width: 600px) {
      .fitmerge-host .merge-radio-group { grid-template-columns: 1fr; }
    }
    .fitmerge-host .merge-radio-tile {
      border: 2px solid var(--ys-line);
      border-radius: 10px;
      padding: 14px 16px;
      cursor: pointer;
      transition: border-color 0.15s ease, background 0.15s ease;
    }
    .fitmerge-host .merge-radio-tile:hover {
      border-color: var(--wf-coral);
    }
    .fitmerge-host .merge-radio-tile input[type="radio"] {
      margin-right: 8px;
    }
    .fitmerge-host .merge-radio-tile input[type="radio"]:checked + .merge-radio-label {
      color: var(--wf-coral);
    }
    .fitmerge-host .merge-radio-tile:has(input:checked) {
      border-color: var(--wf-coral);
      background: rgba(250, 119, 60, 0.05);
    }
    .fitmerge-host .merge-radio-label {
      font-family: var(--ys-font-display);
      letter-spacing: 0.04em;
      color: var(--ys-navy);
      font-weight: 600;
      font-size: 0.94rem;
    }
    .fitmerge-host .merge-radio-help {
      font-size: 0.84rem;
      color: var(--ys-muted);
      margin: 6px 0 0 24px;
    }

    /* Summary */
    .fitmerge-host .merge-summary-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
      gap: 10px;
    }
    .fitmerge-host .merge-summary-tile {
      background: var(--ys-bg-soft);
      border-radius: 10px;
      padding: 12px 14px;
      text-align: center;
    }
    .fitmerge-host .merge-summary-label {
      display: block;
      font-size: 0.74rem;
      color: var(--ys-muted);
      letter-spacing: 0.06em;
      text-transform: uppercase;
      font-family: var(--ys-font-display);
      margin-bottom: 4px;
    }
    .fitmerge-host .merge-summary-value {
      display: block;
      font-family: var(--ys-font-display);
      font-weight: 700;
      color: var(--ys-navy);
      font-size: 1.18rem;
    }
    .fitmerge-host .merge-summary-sub {
      display: block;
      font-size: 0.74rem;
      color: var(--ys-muted);
      margin-top: 2px;
      font-style: italic;
    }

    /* Action row */
    .fitmerge-host .merge-action-row {
      display: flex;
      gap: 10px;
      flex-wrap: wrap;
      justify-content: center;
      margin-top: 14px;
    }
    .fitmerge-host .merge-action-row button {
      font-family: var(--ys-font-display);
      letter-spacing: 0.06em;
      font-size: 0.92rem;
      padding: 12px 22px;
      border-radius: 999px;
      cursor: pointer;
      border: 0;
      transition: transform 0.1s ease, background 0.15s ease, opacity 0.15s ease;
    }
    .fitmerge-host .merge-download-btn {
      background: var(--wf-coral);
      color: #fff;
    }
    .fitmerge-host .merge-download-btn:hover:not(:disabled) {
      transform: translateY(-1px);
    }
    .fitmerge-host .merge-download-btn:disabled {
      opacity: 0.4;
      cursor: not-allowed;
    }
    .fitmerge-host .merge-clear-btn {
      background: transparent;
      color: var(--ys-navy);
      border: 1px solid var(--ys-line);
    }
    .fitmerge-host .merge-clear-btn:hover {
      border-color: #c93939;
      color: #c93939;
    }

    /* Case 2 callout */
    .fitmerge-host .merge-hub-callout {
      margin-top: 22px;
      padding: 18px 22px;
      border-left: 4px solid var(--ys-teal, #00B3A4);
      background: rgba(0, 179, 164, 0.06);
      border-radius: 0 10px 10px 0;
    }
    .fitmerge-host .merge-hub-callout-tag {
      font-family: var(--ys-font-display);
      letter-spacing: 0.14em;
      text-transform: uppercase;
      font-size: 0.72rem;
      color: var(--ys-teal, #00B3A4);
      margin-bottom: 8px;
    }
    .fitmerge-host .merge-hub-callout p {
      margin: 0 0 6px;
    }
    .fitmerge-host .merge-hub-callout p:last-child {
      margin-bottom: 0;
    }