html,
body {
  background-color: #23272a;
  color: white;
  font: 16px/1 sans-serif;

  padding: 0;
  margin: 0;

  width: 100%;
  height: 100%;

  display: flex;
  justify-content: center;
  align-items: center;
  flex-flow: column nowrap;
}

*,
*:before,
*:after {
  box-sizing: border-box;
}

#register {
  width: 30rem;
  border-radius: 0.5rem;
  background-color: #2c2f33;
  padding: 2rem;
}

#register h1 {
  margin: 0 0 2rem;
}

.form-group {
  margin: 2rem 0;
}

.form-group label {
  display: block;
  margin-bottom: 0.75rem;
}

.form-group input {
  font: inherit;
  color: inherit;

  border: none;
  border-radius: 0.25rem;
  padding: 0.5rem;
  display: block;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.08);
}

.form-group input:focus {
  outline: none;
  box-shadow: 0 0 0 0.15rem #7289da;
}

input[name='invcode'] {
  font-family: monospace;
}

input[type='submit'] {
  font: inherit;
  color: inherit;
  cursor: pointer;

  border: none;
  border-radius: 0.25rem;
  display: block;
  width: 100%;
  background-color: #7289da;
  padding: 0.75rem 0;
}

@media (max-width: 600px) {
  #register {
    width: 100% !important;
    background: none !important;
  }
}