gap:0; background:red;">
  <div style="block-size:50px; background:green;"></div>
  <div style="will-change:transform; transform:translateX(60px);">
    <div class="relpos" style="block-size:100px;"></div>
    <div class="relpos" style="block-size:100px;"></div>
    <div class="relpos" style="block-size:150px;"></div>
  </div>
</div>
