Pre-set the width by using an invisible pseudo-element which has the same content and styling as the parent hover style. Use a data attribute, like title
, as the source for content.
li {
display: inline-block;
font-size: 0;
}
li a {
display:inline-block;
text-align:center;
font: normal 16px Arial;
text-transform: uppercase;
}
a:hover {
font-weight:bold;
}
/* SOLUTION */
/* The pseudo element has the same content and hover style, so it pre-sets the width of the element and visibility: hidden hides the pseudo element from actual view. */
a::before {
display: block;
content: attr(title);
font-weight: bold;
height: 0;
overflow: hidden;
visibility: hidden;
}
<ul>
<li><a href="#" title="height">height</a></li>
<li><a href="#" title="icon">icon</a></li>
<li><a href="#" title="left">left</a></li>
<li><a href="#" title="letter-spacing">letter-spacing</a></li>
<li><a href="#" title="line-height">line-height</a></li>
</ul>