body {
  background-color: #eee;
  font-family: "Hiragino Sans GB","Microsoft Yahei",Arial,sans-serif;
}

.form-signin {
  max-width: 400px;
/*   padding: 15px; */
  margin: 0 auto;
}

.input-group.input-width {
  max-width: 400px;
}

.form-signin .form-signin-heading,
{

}

.form-signin .form-control {
  position: relative;
  height: auto;
  -webkit-box-sizing: border-box;
     -moz-box-sizing: border-box;
          box-sizing: border-box;
  font-size: 16px;
}
.form-signin .form-control:focus {
  z-index: 2;
}