Animation tag with w3c validator error as default values

Default value: none 0 ease 0 1 normal none running

from w3c validator:

Error: CSS: animation: Too many values or values are not recognized.
From line 352, column 50; to line 352, column 56
rmal both running;:leftwards_arrow_with_hook:}:leftwards_arrow_with_hook::leftwards_arrow_with_hook:i

the line:
animation: autofill 1ms linear 0s 1 normal both running;:leftwards_arrow_with_hook:

Any idea what is this again o.O ?

From w3schools:

Animation Shorthand Property

The example below uses six of the animation properties:
Example

div {
    animation-name: example;
    animation-duration: 5s;
    animation-timing-function: linear;
    animation-delay: 2s;
    animation-iteration-count: infinite;
    animation-direction: alternate;
}

The same animation effect as above can be achieved by using the shorthand animation property:
Example

div {
    animation: example 5s linear 2s infinite alternate;
} 

https://www.w3schools.com/css/css3_animations.asp

You seem to have 8 listed.

8 listed

animation-name
animation-duration
animation-timing-function
animation-delay
animation-iteration-count
animation-direction
animation-fill-mode
animation-play-state

I refer to your question:

Can’t you use 6 and then add the others with separate statements?
Or add them all separately?

I assume the validation is broken, your code looks right. Any reason why you can’t just ignore it? If you’ve checked the CSS works fine, as expected, then not sure what the validation service is going to give you.