<a href="#" class="border-button"> Hover me </a>
<a href="#" class="border-button"> Hover me, also </a>
.border-button {
  margin: 0.5em; /* Increased margin since the outline expands outside the element */
  outline: solid 5px @border;
  transition: outline 0.6s linear;
}

.border-button:hover { outline-width: 10px; }
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  1. https://codepen.io/shshaw/pen/f7548069c326e3c49d374144db9cb662.less

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