Squircle

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

roundedsolidsquirclelarge-radius

CSS

.btn-020 {
  font: 600 15px/1 system-ui,sans-serif;
  color: #fff;
  background: #4f46e5;
  border: 0;
  border-radius: 18px;
  padding: 16px 28px;
  cursor: pointer;
  transition: border-radius .2s,background .2s
}
.btn-020:hover {
  background: #4338ca;
  border-radius: 12px
}
.btn-020:focus-visible {
  outline: 3px solid rgba(79,70,229,.45);
  outline-offset: 2px
}
.btn-020:active {
  background: #3730a3;
  border-radius: 10px
}

HTML

<button class="btn-020">Open app</button>

Prompt

A chunky squircle button, indigo #4f46e5 with white 15px semibold text, 18px radius, 16px by 28px padding. On hover the corners tighten to 12px and the colour goes #4338ca; active tightens further to 10px at #3730a3. Focus ring 3px translucent indigo.

Squircle

Same shelf