bootstrap 圆形按钮

<button type="button" class="btn btn-default btn-circle"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-primary btn-circle"><i class="glyphicon glyphicon-list"></i></button>
<button type="button" class="btn btn-success btn-circle"><i class="glyphicon glyphicon-link"></i></button>
<button type="button" class="btn btn-info btn-circle"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-warning btn-circle"><i class="glyphicon glyphicon-remove"></i></button>
<button type="button" class="btn btn-danger btn-circle"><i class="glyphicon glyphicon-heart"></i></button>


<h2>lg</h2>
<button type="button" class="btn btn-default btn-circle btn-lg"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-primary btn-circle btn-lg"><i class="glyphicon glyphicon-list"></i></button>
<button type="button" class="btn btn-success btn-circle btn-lg"><i class="glyphicon glyphicon-link"></i></button>
<button type="button" class="btn btn-info btn-circle btn-lg"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-warning btn-circle btn-lg"><i class="glyphicon glyphicon-remove"></i></button>
<button type="button" class="btn btn-danger btn-circle btn-lg"><i class="glyphicon glyphicon-heart"></i></button>


<h2>xl</h2>
<button type="button" class="btn btn-default btn-circle btn-xl"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-primary btn-circle btn-xl"><i class="glyphicon glyphicon-list"></i></button>
<button type="button" class="btn btn-success btn-circle btn-xl"><i class="glyphicon glyphicon-link"></i></button>
<button type="button" class="btn btn-info btn-circle btn-xl"><i class="glyphicon glyphicon-ok"></i></button>
<button type="button" class="btn btn-warning btn-circle btn-xl"><i class="glyphicon glyphicon-remove"></i></button>
<button type="button" class="btn btn-danger btn-circle btn-xl"><i class="glyphicon glyphicon-heart"></i></button>

●css

body{margin:40px;}

.btn-circle {
  width: 30px;
  height: 30px;
  text-align: center;
  padding: 6px 0;
  font-size: 12px;
  line-height: 1.428571429;
  border-radius: 15px;
}
.btn-circle.btn-lg {
  width: 50px;
  height: 50px;
  padding: 10px 16px;
  font-size: 18px;
  line-height: 1.33;
  border-radius: 25px;
}
.btn-circle.btn-xl {
  width: 70px;
  height: 70px;
  padding: 10px 16px;
  font-size: 24px;
  line-height: 1.33;
  border-radius: 35px;
}