When SVGs starting looking weird on your website, it might be because their styles are being overwritten.
For the past few months, I've been working on a fun project with a lot of animation and iconography. I used it as an excuse to dive into SVGs, and to attempt to use SVG elements as much as possible.
It was going well, for awhile. Then, all of a sudden, some of the SVGs started behaving funny. Their outlines changed color. Part of them were missing.
I figured it was clipping masks, and spent some time down that rabbit hole.
By the way, if you can, you should expand you objects before exporting to SVG, and avoid attempting to export clipping masks. Its behavior doesn't seem to be consistent.
Anyways, I had an AHA! moment when diving deeper into SVGs recently. By default, Adobe Illustrator tries to save space by abstracting the CSS directives and using classes to target them. If you look near the top of your SVG file, you might see something like this:
<?xml version="1.0" encoding="utf-8"?>
<!-- Generator: Adobe Illustrator 19.1.0, SVG Export Plug-In . SVG Version: 6.00 Build 0) -->
<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN" "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
<svg version="1.1" id="Layer_1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
viewBox="1532 -160.8 3264.6 521.8" style="enable-background:new 1532 -160.8 3264.6 521.8;" xml:space="preserve">
<!-- Here's where the artwork goes ... -->
And then you'd see
.st0 used throughout the SVG.
Well, Adobe Illustrator is so generic in its class names that if you build two separate SVG files in two separate Illustrator projects, it's likely you'll have a conflict. And because CSS cascades, whichever SVG is loaded last on the page will be the one that controls the styles for any classes it declares.
That's going to lead to unintended results eventually.
To get around this, Illustrator provides the option to put these styles inline. Yes, it may make the file a bit bigger, but it's worth it.
When you are saving to SVG, just choose Style Attributes not Style Elements.
Do that and then you'll see the styles spread throughout and avoid those nasty conflicts!