SOURCE

<button class="btn_1">普通按钮</button>

body {
  background: #fff;
}

button {
  width: 120px;
  vertical-align: middle;
  line-height: 1;
  font-size: 16px;
  padding-top: 12px;
  padding-bottom: 12px;
  cursor: pointer;
  outline: none;
  border-radius: 4px;
  border: none;
  text-align: center;
}

.btn_1 {
  color: #19f;
  border: 1px solid currentcolor;
  transition: color 300ms ease-in;
}

.btn_1:hover {
  color: #1b5;
}

.btn_1:active {
  color: #3322ff;
}