সিএসএস marker-start

<!DOCTYPE html>
<html>
<head>
<meta name="viewport" content="width=device-width, initial-scale=1">
<style>
path {
  fill: none;
  stroke: black;
  stroke-width: 3;
  marker-start: url(#arrow);
}
</style>
</head>
<body>

<svg width="300" height="120">

  <defs>
    <marker id="arrow"
      markerWidth="10"
      markerHeight="10"
      refX="5"
      refY="5"
      orient="auto">
      <path d="M0,0 L10,5 L0,10 Z"></path>
    </marker>
  </defs>

  <path d="M30 60 L270 60"></path>

</svg>

</body>
</html>