fill

html,
body,
svg {
  height: 100%;
}

<svg viewBox="0 0 300 100" xmlns="http://www.w3.org/2000/svg">
  <!-- Basic color fill -->
  <circle cx="50" cy="50" r="40" fill="pink" />

  <!-- Fill circle with a gradient -->
  <defs>
    <radialGradient id="myGradient">
      <stop offset="0%" stop-color="pink" />
      <stop offset="100%" stop-color="black" />
    </radialGradient>
  </defs>

  <circle cx="150" cy="50" r="40" fill="url(#myGradient)" />

  <!--
  Keeping the final state of an animated circle
  which is a circle with a radius of 40.
  -->
  <circle cx="250" cy="50" r="20">
    <animate
      attributeType="XML"
      attributeName="r"
      from="0"
      to="40"
      dur="5s"
      fill="freeze" />
  </circle>
</svg>

<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 300 90">
  <style>
    path {
      stroke-width: 2px;
      marker: url("#circle");
    }
  </style>
  <path d="M 10 44.64 L 30 10 L 70 10 L 90 44.64 L 70 79.28 L 30 79.28 Z"
        stroke="red" fill="orange" />
  <path d="M 100 44.64 L 80 10 L 120 10 L 140 44.64 L 120 79.28 L 80 79.28 Z"
        stroke="green" fill="lightgreen" />
  <path d="M 150 44.64 L 130 10 L 170 10 L 190 44.64 L 170 79.28 L 130 79.28 Z"
        stroke="blue" fill="lightblue" />
  <marker id="circle" markerWidth="12" markerHeight="12"
          refX="6" refY="6" markerUnits="userSpaceOnUse">
    <circle cx="6" cy="6" r="3" stroke-width="2"
            stroke="context-stroke" fill="context-fill"  />
  </marker>
</svg>