<!DOCTYPE html>
<html>
<head>
<title></title>
<style>
  div {
    position: absolute;
    left: 0.3px;
    top: 0.3px;
    width: 10px;
    height: 10px;
  }
  
  .child {
    border: 0.5px solid red;
    -webkit-transform: rotate(180deg);
  }
</style>
</head>
<body>
<p id="container"></p>
<script>
  var container = document.getElementById("container");
  adjustmentY = 0;
  for (i = 0; i < 30; ++i) {
    adjustmentX = 0;
    adjustmentY += 0.1;
    for (j = 0; j < 30; ++j) {
      var e = document.createElement("div");
      e.style.top = (14 * i) + j * adjustmentY + "px";
      e.style.left = (14 * j) + i * adjustmentX + "px";

      var c = document.createElement("div");
      c.className = "child";
      c.style.top = adjustmentY + "px";
      c.style.left = adjustmentX + "px";

      e.appendChild(c);
      container.appendChild(e);
      adjustmentX += 0.1;
    }
  }
</script>
</body>
</html>