.subscribe-form .input-group {
  display: flex;
  align-items: stretch;
  position: relative;
  gap: .5rem;
}

.subscribe-form .form-control {
  flex: 1;
  text-align: end; 
}

.subscribe-form button {
  flex-shrink: 0;
  background-color: var(--primary-color);
  color: #fff;
  border: none;
  padding: 0.2rem 1rem;
  border-radius: 4px !important;
}