Limitations

CSS is not compatible with some SMIL features. Most incompatibilities will throw an error, preventing useless output. However, it's possible that some may have been undetected, so be sure to check the output file in a browser.

Below is a list of unsupported SMIL features.

Most common:

• Motion path elements: <animateMotion>,<mpath>.
• Unmatching repeatCount and begin per element. read more
• Exact repeats. It either plays once or it plays forever.

Less common:

• Animation event attributes: onbegin,onend,onload,onrepeat.
• Additive and cumulative behaviors.
• Specific time values:
  • accessKey, event, repeat and wallclock-sync, time values.
  • Any of these time values except Metric.
  • Syncbase values (with two exceptions). read more
  • lists
    • The only exception is if it's length==2 with [1] being a syncbase value that results in a looped animation (example). Any indexes beyond [1] will be ignored.

Current Status

Animation Elements	Status
<animate>	Partial
<animateColor>	No
<animateTransform>	No
<animateMotion>	Impossible
<mpath>	Impossible
<set>	No

Animation Attributes	Status
attributeName	Partial
attributeType	No
type	No

Animation Timing Attributes	Status
begin	Partial
dur	Yes
end	Partial
min	No
max	No
restart	No
repeatCount	Yes
repeatDur	No
fill	No

Animation Value Attributes	Status
calcMode	No
values	Yes
keyTimes	Yes
keySplines	No
from	Yes
to	Yes
by	No