html - Ring-shaped process spinner with fading gradient effect around the ring

Question

I want to create a ring-shaped process spinner with CSS3 or JavaScript, similar to the loading progress spinner in Android.

The spinner should rotate continuously and be filled with a solid colour that fades out along the rim (i.e. a conical gradient) as in this picture:

How can I achieve this?

Answer 1

This would be trivially easy if only CSS or SVG had conical gradients! Until the conic-gradient() notation matures and gains support, we can approximate the effect by slicing up the gradient and covering the seams somehow.

Below you will find two solutions. The first solution uses an embedded SVG image; the second uses multiple CSS gradients and pseudo-elements.

Both start with a single div with a keyframe animation applied to make it rotate:

HTML:

<div class="spinner"></div>

CSS:

@keyframes rotate {
    from { transform: rotate(0deg);   }
    to   { transform: rotate(360deg); }
}

.spinner {
    animation: rotate 1s linear infinite;
    height: 200px;
    width: 200px;
}

You can use a progress element if you prefer, but you will find it a pain to style. Also note that unless you're using something like prefixfree.js, you'll need to add the vendor-prefixed versions of the @keyframes at-rule and the transform and animation properties.

---

The SVG solution

@keyframes rotate {
    from { transform: rotate(0deg);   }
    to   { transform: rotate(360deg); }
}

.spinner {
    animation: rotate 1s linear infinite;
    background: url('data:image/svg+xml;base64,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') no-repeat;
    height: 200px;
    width: 200px;
}

<div class="spinner"></div>