/* ── LAYOUT ── */
  .app {
    display: flex;
    width: 100%; height: 100vh;
  }

  /* ── 3D VIEWPORT ── */
  .viewport {
    flex: 1;
    position: relative;
    background: linear-gradient(165deg, #EDE9E3 0%, #D8D2C8 50%, #C5BFB5 100%);
    overflow: hidden;
  }
  .viewport canvas { display: block; }

  .viewport-badge {
    position: absolute;
    top: 24px; left: 28px;
    font-family: 'Playfair Display', serif;
    font-size: 20px;
    font-weight: 500;
    color: var(--text);
    letter-spacing: 0.02em;
    user-select: none;
  }
  .viewport-badge span {
    display: block;
    font-family: 'DM Sans', sans-serif;
    font-size: 11px;
    font-weight: 400;
    color: var(--text-muted);
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin-top: 2px;
  }

  .viewport-hint {
    position: absolute;
    bottom: 20px; left: 50%;
    transform: translateX(-50%);
    font-size: 11px;
    color: var(--text-muted);
    background: rgba(255,255,255,0.7);
    backdrop-filter: blur(8px);
    padding: 6px 14px;
    border-radius: 20px;
    user-select: none;
    opacity: 0.7;
  }

  .preview-toggle-wrap {
    position: absolute;
    top: 24px; right: 28px;
    display: flex;
    gap: 4px;
    background: rgba(255,255,255,0.75);
    backdrop-filter: blur(10px);
    border-radius: 8px;
    padding: 4px;
    box-shadow: var(--shadow-md);
  }
  .preview-toggle-wrap .toggle-btn {
    padding: 8px 16px;
    font-size: 12px;
    border: none;
    border-radius: 6px;
    background: transparent;
    color: var(--text-muted);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    font-family: 'DM Sans', sans-serif;
  }
  .preview-toggle-wrap .toggle-btn:hover { background: rgba(0,0,0,0.05); }
  .preview-toggle-wrap .toggle-btn.active {
    background: var(--accent);
    color: white;
    box-shadow: var(--shadow-sm);
  }

  /* ── PRICE DISPLAY ON VIEWPORT ── */
  .dims-display {
    position: absolute;
    bottom: 60px; right: 28px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text);
    background: rgba(255,255,255,0.7);
    backdrop-filter: blur(8px);
    padding: 6px 14px;
    border-radius: 8px;
    user-select: none;
    letter-spacing: 0.02em;
  }
  .dims-display span { font-weight: 600; }

  .price-display {
    position: absolute;
    bottom: 24px; right: 28px;
    text-align: right;
  }
  .price-label {
    font-size: 11px;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-muted);
    margin-bottom: 2px;
  }
  .price-value {
    font-family: 'Playfair Display', serif;
    font-size: 32px;
    font-weight: 600;
    color: var(--price-color);
  }

  /* ── SIDEBAR ── */
  .sidebar {
    width: 380px;
    min-width: 380px;
    height: 100vh;
    background: var(--panel-bg);
    border-left: 1px solid var(--border);
    display: flex;
    flex-direction: column;
    overflow: hidden;
  }

  .sidebar-header {
    padding: 24px 28px 20px;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
  }
  .sidebar-header h2 {
    font-family: 'Playfair Display', serif;
    font-size: 22px;
    font-weight: 500;
    margin-bottom: 4px;
  }
  .sidebar-header p {
    font-size: 13px;
    color: var(--text-muted);
  }

  .sidebar-scroll {
    flex: 1;
    overflow-y: auto;
    padding: 0 28px 28px;
    scrollbar-width: thin;
    scrollbar-color: var(--border) transparent;
  }
  .sidebar-scroll::-webkit-scrollbar { width: 5px; }
  .sidebar-scroll::-webkit-scrollbar-track { background: transparent; }
  .sidebar-scroll::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }


  /* ── RESPONSIVE ── */
  @media (max-width: 900px) {
    .app { flex-direction: column; }
    .viewport { height: 45vh; }
    .sidebar { width: 100%; min-width: unset; height: 55vh; }
  }