CSS如何给字体加边框

<h1>
字 体 边 框
</h1>

h1 {
  background-color:black;
  font-family: "Raleway", sans-serif;
  font-size: 28px;
  color: red;
//下方是加边框的内容
  text-shadow: 4px 4px 0 white, 4px -4px 0 white, -4px -4px 0 white, -4px 4px 0 white, 4px 3px 0 white, 4px -3px 0 white, -4px -3px 0 white, -4px 3px 0 white, 4px 2px 0 white, 4px -2px 0 white, -4px -2px 0 white, -4px 2px 0 white, 4px 1px 0 white, 4px -1px 0 white, -4px -1px 0 white, -4px 1px 0 white, 4px 0px 0 white, 4px 0px 0 white, -4px 0px 0 white, -4px 0px 0 white, 3px 4px 0 white, 3px -4px 0 white, -3px -4px 0 white, -3px 4px 0 white, 3px 3px 0 white, 3px -3px 0 white, -3px -3px 0 white, -3px 3px 0 white, 3px 2px 0 white, 3px -2px 0 white, -3px -2px 0 white, -3px 2px 0 white, 3px 1px 0 white, 3px -1px 0 white, -3px -1px 0 white, -3px 1px 0 white, 3px 0px 0 white, 3px 0px 0 white, -3px 0px 0 white, -3px 0px 0 white, 2px 4px 0 white, 2px -4px 0 white, -2px -4px 0 white, -2px 4px 0 white, 2px 3px 0 white, 2px -3px 0 white, -2px -3px 0 white, -2px 3px 0 white, 2px 2px 0 white, 2px -2px 0 white, -2px -2px 0 white, -2px 2px 0 white, 2px 1px 0 white, 2px -1px 0 white, -2px -1px 0 white, -2px 1px 0 white, 2px 0px 0 white, 2px 0px 0 white, -2px 0px 0 white, -2px 0px 0 white, 1px 4px 0 white, 1px -4px 0 white, -1px -4px 0 white, -1px 4px 0 white, 1px 3px 0 white, 1px -3px 0 white, -1px -3px 0 white, -1px 3px 0 white, 1px 2px 0 white, 1px -2px 0 white, -1px -2px 0 white, -1px 2px 0 white, 1px 1px 0 white, 1px -1px 0 white, -1px -1px 0 white, -1px 1px 0 white, 1px 0px 0 white, 1px 0px 0 white, -1px 0px 0 white, -1px 0px 0 white, 0px 4px 0 white, 0px -4px 0 white, 0px -4px 0 white, 0px 4px 0 white, 0px 3px 0 white, 0px -3px 0 white, 0px -3px 0 white, 0px 3px 0 white, 0px 2px 0 white, 0px -2px 0 white, 0px -2px 0 white, 0px 2px 0 white, 0px 1px 0 white, 0px -1px 0 white, 0px -1px 0 white, 0px 1px 0 white, 0px 0px 0 white, 0px 0px 0 white, 0px 0px 0 white, 0px 0px 0 white, 0 0 0 white;
}