SOURCE

<div>
  <a class="btn1 big">
    按钮一
  </a>
  <input class="btn1 big" type="button" value="按钮二" />
  <button class="btn1 big">
    按钮三
  </button>
</div>

.btn1 {
  font-size: 14px;
  -webkit-border-radius: 4px;
  border-radius: 4px;
  color: #fff;
  background-color: #00a3cf;
  border: 1px solid #008fb5;
  border-color: #00abd9 #008fb5 #008fb5 #00abd9;
  /*box-shadow: 0 1px 1px rgba(255, 255, 255, 0.5) inset, 0 0 1px rgba(255, 255, 255, 0.5) inset;*/
  box-shadow: 1px 1px 2px #eeeeee;
  display: inline-block;
  cursor: pointer;
  text-align: center;
  background: -webkit-linear-gradient(#fff -6%, #73cde5 6%, #00a3cf 100%);
  background: -moz-linear-gradient(#fff -6%, #73cde5 6%, #00a3cf 100%);
  background: linear-gradient(#fff -6%, #73cde5 6%, #00a3cf 100%);
  -pie-background: linear-gradient(#fff 1%, #73cde5 6%, #00a3cf 100%);
  behavior: url(../js/PIE.htc)\9;
  vertical-align: middle;
  overflow: hidden;
  margin: 0 3px;
  +padding: 0px;
  position: relative\9;
}

.btn1:hover {
  color: #fff;
  background: -webkit-linear-gradient(#fff -6%, #73cde5 6%, #008fb5 94%, #73cde5 100%);
  background: -moz-linear-gradient(#fff -6%, #73cde5 6%, #008fb5 94%, #73cde5 100%);
  background: linear-gradient(#fff -6%, #73cde5 6%, #008fb5 94%, #73cde5 100%);
  -pie-background: linear-gradient(#fff 1%, #73cde5 6%, #008fb5 94%, #73cde5 100%);
  behavior: url(../js/PIE.htc)\9;
}

.big {
  height: 30px;
  line-height: 28px;
  padding: 0 16px;
}