CSS3 Navigation Button Animation - html

Question

I have animated my navigation buttons that expand upon hover, but they keep on disrupting the flow of the rest of the page. I've tried using z-index to take them out of the flow, but that isn't working, either. Is there a way to do this with out the buttons shoving everything out of whack? Here's my relevant code so far:
.btn-group .button {
background-color: teal;
border: 2px solid orange;
color: orange;
padding: 2px 15px;
text-align: center;
text-decoration: none;
display: inline-block;
cursor: pointer;
float: left;
font-size: 1em;
border-radius: 50%;
margin: 5px 0 5px 5px;
padding-left: 30px;
position: relative;
z-index: 1; }
.btn-group .button:hover {
background-color: cadetblue; }
.button span {
cursor: pointer;
display: inline-block;
position: relative;
transition: 0.5s; }
.button span:after {
content: '\00bb';
opacity: 0;
top: 0;
right: -20px;
transition: 0s;
padding-left: 10px; }
.button:hover span {
padding: 10px;
color: black;
font-size: 1.5em; }
.button:hover span:after {
opacity: 1;
right: 0;
color: black; }
Thanks for your help!

Answer 1

You have to limit your animations to properties that do not interfere with object's position and dimensions in the document flow.
Those are: transform, left, right, bottom and top. For the last 4, in order to work, you also need position:relative on the button. When using any of these, even though you see the element moving, its place is kept in the flow, just like it would still be there. Only its projected image is moved/transformed.
Example with transform:
.button {
margin: 1rem;
transition : transform .3s cubic-bezier(.4,0,.2,1);
display: inline-block;
border: 1px solid black;
padding: 1rem;
}
.button:hover {
transform: scale(1.1);
}
.red {
background-color: red;
padding: 1rem;
color: white;
}
<a class="button">Example with transform</a>
<div class="red">see? I'm not moving</div>
That's how the vast majority of web animations are done (using transforms).
As an alternative, if you really want to animate properties that would normally affect the rest of the document, you will need to remove your element from document flow. For that, you need to:
wrap your element in a wrapper (placeholder) of desired dimensions (which will never move and keep everything in place), and give the wrapper position:relative,
set position:absolute on the button.
Now you can animate anything on the button without affecting the rest of the document.
But remember, the wrapper needs to have proper dimensions, as the button, now being absolutely positioned, will no longer occupy any space in the document flow. Also, note that your button is now relative to its placeholder. If the placeholder moves, the button moves too.
Example with absolute positioning and wrapping:
.wrapper {
height: 5rem;
position: relative;
}
.button {
position: absolute;
top: 1rem;
padding: 1rem;
transition: all .3s cubic-bezier(.4,0,.2,1);
border: 1px solid black;
}
.button:hover {
top: .5rem;
padding: 1.5rem;
}
.red {
background-color: red;
padding: 1rem;
color: white;
}
<div class="wrapper">
<a class="button">Example with absolute positioning and wrapping</a>
</div>
<div class="red">see? I'm not moving</div>
That's the basics.
As a side note, best practices require you to limit animations to a very select and limited bunch or properties which do not hit browser performance: the bunch is made of exactly two items:
transforms
and opacity.
You animate anything else... boom!, your scroll begins to stagger on devices with limited resources. There is quite a lot to read on the subject, but here's a good one.

Answer 2

Setting a high z-index does not take the element out of the document flow, you need to use absolute positioning for your button.
i.e.
.btn-group{
position: relative;
}
.button{
position: absolute;
}