html - Circle loading animation

Question

I'm trying to create Apple's OS X circle loading animation.

What I have tried so far:

.animation-wrapper {
  width: 200px;
  height: 200px;
  border: 1px solid black;
  border-radius: 50%;
  position: relative;
  overflow: hidden;
  filter: brightness(0.8);
  -webkit-filter: brightness(0.8);
}
.pie-piece1 {
  position: absolute;
  width: 50%;
  height: 50%;
  bottom: 0;
  left: 0;
  background: linear-gradient(to right, rgba(255, 0, 0, 1) 0%, rgba(255, 255, 0, 1) 100%);
}
.pie-piece2 {
  position: absolute;
  width: 50%;
  height: 50%;
  bottom: 0;
  right: 0;
  background: linear-gradient(to right, rgba(255, 255, 0, 1) 0%, rgba(0, 255, 0, 1) 100%);
}
.pie-piece3 {
  position: absolute;
  width: 50%;
  height: 50%;
  top: 0;
  left: 0;
  background: linear-gradient(to right, rgba(255, 0, 0, 1) 0%, rgba(255, 0, 255, 1) 100%);
}
.pie-piece4 {
  position: absolute;
  width: 50%;
  height: 50%;
  top: 0;
  right: 0;
  background: linear-gradient(to right, rgba(255, 0, 255, 1) 0%, rgba(0, 0, 255, 1) 100%);
}
.rotating-spinners {
  position: absolute;
}
.spike {
  fill: rgba(22, 22, 22, 0.5);
}

<figure class="animation-wrapper">
  <div class="pie-piece1"></div>
  <div class="pie-piece2"></div>
  <div class="pie-piece3"></div>
  <div class="pie-piece4"></div>
  <svg class="rotating-spinners" width="100%" height="100%" viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
    <defs>
      <path id="spin-part" class="spike" d="M 65,-40 C 65,-40 80,20 50,50 60,40 50,-40 50,-40Z" />
    </defs>
    <use x="0" y="0" xlink:href="#spin-part" />
    <use x="0" y="0" xlink:href="#spin-part" transform="rotate(60, 50, 50)" />
    <use x="0" y="0" xlink:href="#spin-part" transform="rotate(120, 50, 50)" />
    <use x="0" y="0" xlink:href="#spin-part" transform="rotate(180, 50, 50)" />
    <use x="0" y="0" xlink:href="#spin-part" transform="rotate(240, 50, 50)" />
    <use x="0" y="0" xlink:href="#spin-part" transform="rotate(300, 50, 50)" />
  </svg>
</figure>

Answer 1

Here's my SVG-only version. The background colour wheel isn't perfect, but I think I got fairly close.

<svg width="135" height="135" viewBox="0 0 200 200">
    <defs>
        <filter id="blur" color-interpolation-filters="linear">
            <feGaussianBlur in="SourceGraphic" stdDeviation="11"/>
        </filter>
        <mask id="mask">
            <circle cx="0" cy="0" r="90" fill="white"/>
        </mask>
        <linearGradient id="gloss" x2="0" y2="0.4">
            <stop offset="0" stop-color="white" stop-opacity="0.5"/>
            <stop offset="1" stop-color="white" stop-opacity="0"/>
        </linearGradient>
    </defs>

    <g transform="translate(100,100)" mask="url(#mask)">
        <g filter="url(#blur)">
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#c44"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#c09" transform="rotate(30)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#c0c" transform="rotate(60)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#90c" transform="rotate(90)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#44c" transform="rotate(120)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#09c" transform="rotate(150)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#0cc" transform="rotate(180)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#0c9" transform="rotate(210)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#4c4" transform="rotate(240)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#9c0" transform="rotate(270)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#cc0" transform="rotate(300)"/>
            <polygon points="0,0, -100,-26.8, -100,26.8" fill="#c90" transform="rotate(330)"/>
        </g>
        <g transform="scale(0.9,0.9)">
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4"/>
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4" transform="rotate(60)"/>
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4" transform="rotate(120)"/>
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4" transform="rotate(180)"/>
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4" transform="rotate(240)"/>
            <path d="M0,0C5,-61,-32,-86,-95,-90L-100,-46C-65,-53,-24,-35,0,0Z" fill="black" fill-opacity="0.4" transform="rotate(300)"/>
            <animateTransform attributeType="xml" attributeName="transform" type="rotate" from="0" to="360" dur="4s" repeatCount="indefinite"/>

        </g>
        <circle r="83" fill="url(#gloss)"/>
        <circle r="90" fill="none" stroke="black" stroke-width="2"/>
    </g>
</svg>