JSFiddle - React, Tailwind, and code Playground

HTML

<a href="#">Главная</a>

CSS

a {
  display: block;
  width: 100px;
  height: 30px;
  line-height: 30px;
  margin: 0 30px;
  text-align: center;
  position: relative;
  background-color: #ccc;
}

a::before,
a::after {
  content: '';
  position: absolute;
  top: 0;
  width: 0;
  height: 0;
  border: 15px solid transparent;
}

a::before {
  right: 100%;
  border-right-color: #ccc;
}
a::after {
  left: 100%;
  border-left-color: #ccc;
}