omniauth--omniauth/lib/omniauth/form.css

body {
  background: #ccc;
  font-family: "Lucida Grande", "Lucida Sans", Helvetica, Arial, sans-serif;
}

h1 {
  text-align: center;
  margin: 30px auto 0px;
  font-size: 18px;
  padding: 10px 10px 15px;
  background: #555;
  color: white;
  width: 320px;
  border: 10px solid #444;
  border-bottom: 0;
  -moz-border-radius-topleft: 10px;
  -moz-border-radius-topright: 10px;
  -webkit-border-top-left-radius: 10px;
  -webkit-border-top-right-radius: 10px;
  border-top-left-radius: 10px;
  border-top-right-radius: 10px;
}

h1, form {
  -moz-box-shadow: 2px 2px 7px rgba(0,0,0,0.3);
  -webkit-box-shadow: 2px 2px 7px rgba(0,0,0,0.3);
}

form {
  background: white;
  border: 10px solid #eee;
  border-top: 0;
  padding: 20px;
  margin: 0px auto 40px;
  width: 300px;
  -moz-border-radius-bottomleft: 10px;
  -moz-border-radius-bottomright: 10px;
  -webkit-border-bottom-left-radius: 10px;
  -webkit-border-bottom-right-radius: 10px;
  border-bottom-left-radius: 10px;
  border-bottom-right-radius: 10px;
}

label {
  display: block;
  font-weight: bold;
  margin-bottom: 5px;
}

input {
  font-size: 18px;
  padding: 4px 8px;
  display: block;
  margin-bottom: 10px;
  width: 280px;
}

input#identifier, input#openid_url {
  background: url(https://openid.net/images/login-bg.gif) no-repeat;
  background-position: 0 50%;
  padding-left: 18px;
}

button {
  font-size: 22px;
  padding: 4px 8px;
  display: block;
  margin: 20px auto 0;
}

fieldset {
  border: 1px solid #ccc;
  border-left: 0;
  border-right: 0;
  padding: 10px 0;
}

fieldset input {
  width: 260px;
  font-size: 16px;
}