[JS] SVG 선 끝 둥글게

stroke-linecap 속성을 이용하자!

https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/stroke-linecap

<svg viewBox="0 0 6 6" xmlns="http://www.w3.org/2000/svg">
  <!-- Effect of the (default) "butt" value -->
  <line x1="1" y1="1" x2="5" y2="1" stroke="black" stroke-linecap="butt" />

  <!-- Effect of the "round" value -->
  <line x1="1" y1="3" x2="5" y2="3" stroke="black" stroke-linecap="round" />

  <!-- Effect of the "square" value -->
  <line x1="1" y1="5" x2="5" y2="5" stroke="black" stroke-linecap="square" />

  <!--
  the following pink lines highlight the
  position of the path for each stroke
  -->
  <path d="M1,1 h4 M1,3 h4 M1,5 h4" stroke="pink" stroke-width="0.025" />
</svg>