:root {
      --webp-color: #2563EB;
      --webp-bg:    #EFF6FF;
    }

.webp-badge {
      font-size: 11px; font-weight: 400;
      background: var(--webp-color); color: white;
      padding: 4px 12px; letter-spacing: 0.15em;
    }

    .drop-formats {
      display: flex; gap: 6px; margin-top: 14px; flex-wrap: wrap; justify-content: center;
    }
    .fmt-tag {
      font-size: 10px; letter-spacing: 0.1em;
      padding: 3px 9px; border: 1px solid var(--border); color: var(--ink-light);
    }

    /* Multi-file indicator */
    .multi-badge {
      position: absolute; top: 14px; right: 14px;
      font-size: 10px; letter-spacing: 0.12em;
      background: var(--webp-bg); color: var(--webp-color);
      padding: 3px 10px; border: 1px solid var(--webp-color);
    }

    /* Quality */
    .quality-wrap { display: flex; align-items: center; gap: 14px; flex: 1; min-width: 200px; }

    .quality-num {
      font-size: 24px; font-weight: 400;
      color: var(--ink); min-width: 36px; text-align: right; line-height: 1;
    }
    .quality-grade { font-size: 11px; color: var(--ink-light); font-weight: 300; min-width: 96px; }

    /* Lossless toggle */
    .toggle-row { display: flex; align-items: center; gap: 10px; }
    .toggle-checkbox {
      appearance: none; width: 32px; height: 18px; background: var(--border-mid);
      border-radius: 9px; cursor: pointer; position: relative; transition: background 0.2s; flex-shrink: 0;
    }
    .toggle-checkbox::after {
      content: ''; position: absolute; width: 12px; height: 12px; background: white;
      border-radius: 50%; top: 3px; left: 3px; transition: left 0.2s;
    }
    .toggle-checkbox:checked { background: var(--webp-color); }
    .toggle-checkbox:checked::after { left: 17px; }
    .toggle-label { font-size: 12px; font-weight: 300; color: var(--ink); cursor: pointer; white-space: nowrap; }

    /* Alpha preserve */
    .alpha-note {
      font-size: 11px; color: var(--ink-light); font-weight: 300;
      display: flex; align-items: center; gap: 6px;
    }
    .alpha-dot {
      width: 8px; height: 8px; flex-shrink: 0;
      background: repeating-conic-gradient(#ccc 0% 25%, white 0% 50%) 0 0 / 8px 8px;
    }

    /* ── File List (multi-file) ── */
    .file-list {
      border: 1px solid var(--border); background: var(--card); overflow: hidden;
    }
    .file-list-header {
      display: flex; align-items: center; justify-content: space-between;
      padding: 10px 16px; border-bottom: 1px solid var(--border); background: var(--bg);
    }
    .file-list-title {
      font-size: 10px; letter-spacing: 0.2em;
      color: var(--ink-light); text-transform: uppercase;
    }
    .file-list-count {
      font-size: 10px; color: var(--blue);
    }

    .file-rows { max-height: 240px; overflow-y: auto; }
    .file-row {
      display: grid; grid-template-columns: auto 1fr auto auto auto;
      align-items: center; gap: 12px; padding: 10px 16px;
      border-bottom: 1px solid var(--border); transition: background 0.1s;
    }
    .file-row:last-child { border-bottom: none; }
    .file-row:hover { background: #FFFFFF; }

    .file-thumb {
      width: 36px; height: 36px; object-fit: cover; display: block;
      background: repeating-conic-gradient(#E8EAED 0% 25%, var(--bg) 0% 50%) 0 0 / 8px 8px;
      flex-shrink: 0;
    }
    .file-name {
      font-size: 12px; color: var(--ink); font-weight: 300;
      white-space: nowrap; overflow: hidden; text-overflow: ellipsis; min-width: 0;
    }
    .file-fmt {
      font-size: 10px; color: var(--ink-light);
      border: 1px solid var(--border); padding: 2px 7px; flex-shrink: 0;
    }
    .file-size {
      font-size: 11px; color: var(--ink-light); flex-shrink: 0;
    }
    .file-status {
      font-size: 10px; flex-shrink: 0;
      min-width: 72px; text-align: right;
    }
    .status-waiting  { color: var(--ink-xlight); }
    .status-done     { color: var(--green); }
    .status-error    { color: #DC2626; }

    /* ── Preview (single file) ── */
    .preview-wrapper {
      display: grid; grid-template-columns: 1fr 1fr;
      gap: 1px; background: var(--border); border: 1px solid var(--border);
    }
    .preview-pane { background: var(--card); display: flex; flex-direction: column; }
    .pane-header {
      display: flex; align-items: center; justify-content: space-between;
      padding: 10px 16px; border-bottom: 1px solid var(--border); background: var(--bg);
    }
    .pane-title {
      font-size: 10px; letter-spacing: 0.2em;
      color: var(--ink-light); text-transform: uppercase;
    }
    .badge-src  { background: var(--bg); color: var(--ink-light); border: 1px solid var(--border); }
    .badge-webp { background: var(--webp-bg); color: var(--webp-color); }
    .pane-meta { font-size: 10px; color: var(--ink-light); }

    .pane-img-area {
      flex: 1; display: flex; align-items: center; justify-content: center;
      min-height: 280px; padding: 20px;
      background: repeating-conic-gradient(#E8EAED 0% 25%, var(--bg) 0% 50%) 0 0 / 16px 16px;
    }
    .pane-img-area img {
      max-width: 100%; max-height: 340px; object-fit: contain;
      display: block; box-shadow: 0 4px 24px rgba(0,0,0,0.12);
    }
    .pane-placeholder {
      display: flex; flex-direction: column; align-items: center;
      justify-content: center; gap: 8px; color: var(--ink-xlight);
      font-size: 12px; font-weight: 300; letter-spacing: 0.08em; width: 100%;
    }
    .pane-placeholder-icon { font-size: 28px; opacity: 0.35; }

    .pane-footer {
      padding: 12px 16px; border-top: 1px solid var(--border);
      display: flex; align-items: center; justify-content: space-between;
    }

    .reduction-badge {
      font-size: 11px; padding: 3px 10px; letter-spacing: 0.05em;
    }
    .reduction-badge.good { background: var(--green-bg); color: var(--green); }
    .reduction-badge.warn { background: #FEF3C7; color: #92400E; }

    /* ── Saving Strip ── */
    .saving-strip { display: flex; align-items: stretch; border: 1px solid var(--border); background: var(--card); }
    .saving-big {
      padding: 20px 28px; background: var(--webp-color); color: white;
      display: flex; flex-direction: column; justify-content: center; gap: 2px; flex-shrink: 0;
    }
    .saving-big-label { font-size: 9px; letter-spacing: 0.2em; color: rgba(255,255,255,0.5); text-transform: uppercase; }
    .saving-big-num   { font-size: 40px; font-weight: 400; letter-spacing: -0.02em; line-height: 1; }
    .saving-big-unit  { font-size: 11px; color: rgba(255,255,255,0.5); letter-spacing: 0.1em; }

    .saving-details { display: flex; flex: 1; }
    .saving-detail-item {
      flex: 1; padding: 16px 20px; border-right: 1px solid var(--border);
      display: flex; flex-direction: column; justify-content: center; gap: 3px;
    }
    .saving-detail-item:last-child { border-right: none; }
    .saving-detail-key { font-size: 9px; letter-spacing: 0.2em; color: var(--ink-light); text-transform: uppercase; }
    .saving-detail-val { font-size: 18px; color: var(--ink); }

    /* ── Action Bar ── */

    .convert-btn {
      font-size: 12px; letter-spacing: 0.15em;
      background: var(--webp-color); color: white; border: none; height: 48px;
      padding: 0 32px; cursor: pointer; transition: opacity 0.15s, transform 0.1s;
      display: flex; align-items: center; gap: 10px;
    }
    .convert-btn:hover { opacity: 0.88; }
    .convert-btn:active { transform: scale(0.98); }
    .convert-btn:disabled { opacity: 0.35; cursor: not-allowed; }

    .download-btn.hidden, .reset-btn.hidden { display: none; }

    .download-all-btn {
      font-size: 12px; letter-spacing: 0.15em;
      background: var(--ink); color: var(--bg); border: none; height: 48px;
      padding: 0 28px; cursor: pointer; transition: background 0.15s;
      display: flex; align-items: center; gap: 10px;
    }
    .download-all-btn:hover { background: var(--blue); }
    .download-all-btn.hidden { display: none; }

    /* Spinner */

    /* Info strip */
    .info-strip { display: flex; border: 1px solid var(--border); background: var(--card); overflow: hidden; }

    /* Fade */

    /* Footer */

    /* Responsive */

/* ============================================================
   Responsive fix: webp-converter
   ============================================================ */
@media (max-width: 700px) {
  .quality-wrap,
  .toggle-row,
  .alpha-note {
    width: 100%;
    min-width: 0;
    flex-wrap: wrap;
  }

  .quality-wrap input[type="range"] {
    flex: 1 1 auto;
    min-width: 0;
  }

  .quality-grade {
    min-width: 0;
  }

  .toggle-label {
    white-space: normal;
  }

  .file-list-header,
  .file-row {
    min-width: 0;
  }

  .file-row {
    grid-template-columns: 44px 1fr;
    gap: 8px 10px;
  }

  .file-fmt,
  .file-size,
  .file-status {
    grid-column: 2;
    min-width: 0;
    text-align: left;
  }

  .preview-wrapper {
    grid-template-columns: 1fr !important;
  }

  .pane-header,
  .pane-footer {
    flex-wrap: wrap;
    gap: 8px;
  }

  .pane-img-area {
    min-height: 220px;
    padding: 14px;
  }

  .pane-img-area img {
    max-height: 260px;
  }

  .saving-strip {
    flex-direction: column;
  }

  .saving-details {
    flex-direction: column;
  }

  .saving-detail-item {
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .saving-detail-item:last-child {
    border-bottom: none;
  }
}