<svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <style type="text/css"><![CDATA[
      line {
        stroke: green;
        stroke-width: 50px;
        marker-start: url(#marker);
        marker-mid: url(#marker);
        marker-end: url(#marker);
      }
      ]]>
    </style>
  <defs>
    <marker id="marker" viewBox="0 0 10 10" refX="1" refY="5"
      markerUnits="strokeWidth" orient="auto"
      markerWidth="2" markerHeight="2">
      <polyline points="0,0 10,0 10,10 0,10 0,0" fill="red" />
    </marker>
  </defs>

  <line x1="0" y1="0" x2="100" y2="100" style="marker-start: none;marker-mid: none;marker-end: none;" />
</svg>