Add animation delay to li automatically - css

Question

I have a slideshow with CSS3 which have animation-delay in each child,
but this is not dynamic because for each tag I should add nth-child ,
Is there any way to add animation-delay automatically to li tags?
this is CSS code:
.cb-slideshow li:nth-child(2) span {
-webkit-animation-delay: 6s;
-moz-animation-delay: 6s;
-o-animation-delay: 6s;
-ms-animation-delay: 6s;
animation-delay: 6s;
}
.cb-slideshow li:nth-child(3) span {
-webkit-animation-delay: 12s;
-moz-animation-delay: 12s;
-o-animation-delay: 12s;
-ms-animation-delay: 12s;
animation-delay: 12s;
}
.cb-slideshow li:nth-child(4) span {
-webkit-animation-delay: 18s;
-moz-animation-delay: 18s;
-o-animation-delay: 18s;
-ms-animation-delay: 18s;
animation-delay: 18s;
}
.cb-slideshow li:nth-child(5) span {
-webkit-animation-delay: 24s;
-moz-animation-delay: 24s;
-o-animation-delay: 24s;
-ms-animation-delay: 24s;
animation-delay: 24s;
}
.cb-slideshow li:nth-child(6) span {
-webkit-animation-delay: 30s;
-moz-animation-delay: 30s;
-o-animation-delay: 30s;
-ms-animation-delay: 30s;
animation-delay: 30s;
}
I want to change this code to add 6s delay to each tags.

Answer 1

There is no way to handle it dynamically except adding inline style dynamically or with javascript
for example
.cb-slideshow li {
animation: FadeIn 1s linear;
animation-fill-mode: both;
}
#keyframes FadeIn {
0% {
opacity: 0;
transform: scale(.1);
}
85% {
opacity: 1;
transform: scale(1.05);
}
100% {
transform: scale(1);
}
}
<div class="cb-slideshow">
<li style="animation-delay: 1s;">test text</li>
<li style="animation-delay: 2s;">test text</li>
<li style="animation-delay: 3s;">test text</li>
<li style="animation-delay: 4s;">test text</li>
<li style="animation-delay: 5s;">test text</li>
</div>

Answer 2

You could use PHP to dynamically echo each part of the style, or intergrate it right into the css.
For example
.button:hover {
border: 10px solid;
transition: <?php echo $lot ?>;
}
Where $lot is the animation time.
I dont know how to get the nth-child(N) in php, but there is undoubtably a way.
Sorry if this wasn't very useful, just wanted to say that php would be a good way to do it.