<button
  class="theme-toggle"
  type="button"
  title="Toggle theme"
  aria-label="Toggle theme"
>
  <svg
    xmlns="http://www.w3.org/2000/svg"
    aria-hidden="true"
    width="1em"
    height="1em"
    class="theme-toggle__eclipse"
    fill="currentColor"
    viewBox="0 0 32 32"
  >
    <clipPath id="theme-toggle__eclipse__cutout">
      <path d="M0 0h64v32h-64zm36 16a1 1 0 0024 1 1 1 0 00-24-1" />
    </clipPath>
    <g clip-path="url(#theme-toggle__eclipse__cutout)">
      <circle cx="16" cy="16" r="16" />
    </g>
  </svg>
</button>