<div>I wish my outline was rounded</div>

body, html {
  height: 100%;
}

body {
  display: grid;
  justify-content: center;
  align-items: center;
}

div {
  font-size: 1.2rem;
  padding: 1em;
  width: fit-content;
  border: 1em solid deeppink;
  border-radius: 1em;
  outline: 1em solid blue;
}