Underline grow

Underline grow: a CSS button. Copy the rules, or the prompt that rebuilds it.

underlinetext-buttonborder-drawminimal

CSS

.btn-065 {
  position: relative;
  font: 500 15px/1 system-ui,sans-serif;
  color: #111827;
  background: none;
  border: 0;
  padding: 6px 2px;
  cursor: pointer
}
.btn-065::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 2px;
  background: #111827;
  transform: scaleX(0);
  transform-origin: left;
  transition: transform .25s
}
.btn-065:hover::after {
  transform: scaleX(1)
}
.btn-065:focus-visible {
  outline: 2px solid #111827;
  outline-offset: 4px
}
.btn-065:active {
  color: #4b5563
}

HTML

<button class="btn-065">Read more</button>

Prompt

A plain text button (15px medium, #111827, no background or border, 6px by 2px padding) with a 2px underline that draws from left to right on hover (scaleX 0 to 1, origin left, 250ms). Active greys the text to #4b5563. Focus outline 2px dark offset 4px.

Underline grow

Same shelf