<div class="letter">开始游戏</div>

.letter{
  width: 200px;
  height: 100px;
  text-align: center;
  line-height: 100px;
  background: rgb(255, 200, 42);
  font-size: 36px;
  font-weight: 400;
  z-index: 2;
  color: rgb(255, 255, 255) ;
  --stroke-width: 0.16em;
  --stroke-color: #c9721a;
  position: relative;
  letter-spacing: var(--letter-spacing, 0.15em);// 字体之间的间距
}
.letter::before{
  content: '开始游戏';
  position: absolute;
  z-index: -1;
  -webkit-text-stroke: var(--stroke-width, 0.1em) var(--stroke-color, #c9721a);
}