/* ── SISTEMA / GALLERY ────────────────── */
 
 #sistema {
    padding: 100px 5%;
    background: linear-gradient(170deg, #f0f8ff 0%, #ffffff 60%);
    position: relative;
    overflow: hidden;
  }
  #sistema::before {
    content: '';
    position: absolute; top: -200px; right: -200px;
    width: 600px; height: 600px; border-radius: 50%;
    background: radial-gradient(circle, rgba(74,163,212,.07) 0%, transparent 70%);
    pointer-events: none;
  }

  .sistema-header {
    max-width: 1200px; margin: 0 auto;
    display: grid; grid-template-columns: 1fr 1fr; gap: 60px; align-items: center;
    margin-bottom: 72px;
  }

  .sistema-features {
    display: flex; flex-direction: column; gap: 20px; margin-top: 36px;
  }
  .sistema-feature {
    display: flex; align-items: flex-start; gap: 14px;
    padding: 16px 18px;
    border-radius: 10px;
    border: 1px solid rgba(74,163,212,.12);
    background: rgba(234,245,252,.5);
    transition: border-color .3s, background .3s, transform .3s;
  }
  .sistema-feature:hover {
    border-color: rgba(74,163,212,.35);
    background: rgba(234,245,252,.9);
    transform: translateX(4px);
  }
  .sistema-feature-icon {
    width: 38px; height: 38px; flex-shrink: 0;
    border-radius: 9px;
    background: linear-gradient(135deg, var(--blue-mid), var(--accent));
    display: flex; align-items: center; justify-content: center;
    color: var(--white); font-size: .85rem;
    box-shadow: 0 4px 14px rgba(26,95,158,.2);
  }
  .sistema-feature-text strong {
    display: block; font-size: .875rem; font-weight: 600; color: var(--blue-deep); margin-bottom: 2px;
  }
  .sistema-feature-text span {
    font-size: .8rem; color: var(--text-light); line-height: 1.5;
  }

  /* Lightbox gallery grid */
  .gallery-grid {
    max-width: 1200px; margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: auto;
    gap: 16px;
  }

  .gallery-item {
    position: relative; overflow: hidden; border-radius: 12px;
    cursor: pointer;
    border: 1.5px solid rgba(74,163,212,.15);
    background: var(--blue-ghost);
    aspect-ratio: 16/10;
    transition: transform .3s, box-shadow .3s, border-color .3s;
  }
  .gallery-item:first-child {
    grid-column: span 2;
    aspect-ratio: 16/9;
  }
  .gallery-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 18px 50px rgba(26,95,158,.15);
    border-color: rgba(74,163,212,.4);
  }
  .gallery-item img {
    width: 100%; height: 100%; object-fit: cover;
    display: block;
    transition: transform .4s ease;
  }
  .gallery-item:hover img { transform: scale(1.04); }

  /* Placeholder when no image is loaded */
  .gallery-placeholder {
    width: 100%; height: 100%;
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    gap: 10px;
    color: var(--blue-light);
  }
  .gallery-placeholder i { font-size: 2rem; opacity: .5; }
  .gallery-placeholder span { font-size: .75rem; font-weight: 500; color: var(--text-light); letter-spacing: .06em; }

  .gallery-overlay {
    position: absolute; inset: 0;
    background: linear-gradient(to top, rgba(13,42,74,.75) 0%, transparent 55%);
    opacity: 0; transition: opacity .3s;
    display: flex; align-items: flex-end; padding: 18px 20px;
  }
  .gallery-item:hover .gallery-overlay { opacity: 1; }
  .gallery-overlay-label {
    color: var(--white); font-size: .8rem; font-weight: 600; letter-spacing: .06em;
    display: flex; align-items: center; gap: 8px;
  }
  .gallery-overlay-label i { font-size: .85rem; color: var(--blue-light); }

  /* Gallery add button */
  .gallery-add-btn {
    display: flex; flex-direction: column; align-items: center; justify-content: center;
    gap: 10px;
    border: 2px dashed rgba(74,163,212,.35);
    border-radius: 12px;
    aspect-ratio: 16/10;
    cursor: pointer;
    background: rgba(234,245,252,.4);
    transition: border-color .3s, background .3s;
    color: var(--blue-light);
  }
  .gallery-add-btn:hover {
    border-color: var(--blue-mid);
    background: rgba(74,163,212,.06);
    color: var(--blue-mid);
  }
  .gallery-add-btn i { font-size: 1.6rem; }
  .gallery-add-btn span { font-size: .75rem; font-weight: 600; letter-spacing: .1em; text-transform: uppercase; }