style.css

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: sans-serif;
}

body {
  background-color: rgb(77, 77, 77);
  display: flex;
  align-items: center;
  justify-content: space-around;
  flex-wrap: wrap;
  flex-direction: column;
}

.nav {
  display: flex;
  flex-direction: column;
  margin-top: 50px;
  margin-bottom: 50px;
}

.nav a {
  text-decoration: none;
  font-size: 22px;
  color: black;
  margin-top: 40px;
}

.nav a button {
  width: 200px;
  height: 50px;
  background-color: rgb(255, 153, 0);
  font-size: 15.5px;
  font-weight: 700;
  cursor: pointer;
  outline: none;
  border: none;
  border-radius: 25px;
  color: #fff;
  box-shadow: 0 0 25px #ff7b00;
  transition: 0.5s;
}

.nav a button:hover {
  background-color: lightseagreen;
  box-shadow: 0 0 25px lightseagreen, 0 0 50px lightseagreen;
}

h2 {
  color: #f7f7f7;
  margin-bottom: 18px;
}

@media (max-width:900px) {
  body {
   text-align: center;
  }
  .nav {
    margin-bottom: 40px;
  }
}