html,
body {
  height: 100%;
  background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
}

.form-signin {
  max-width: 420px;
  padding: 2.5rem;
  background: rgba(30, 41, 59, 0.8);
  border-radius: 20px;
  border: 1px solid rgba(59, 130, 246, 0.3);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(10px);
}

.form-signin img {
  display: block;
  margin: 0 auto 2rem;
  filter: drop-shadow(0 4px 12px rgba(59, 130, 246, 0.4));
}

.form-signin h1 {
  color: #f1f5f9;
  text-align: center;
  font-weight: 600;
  margin-bottom: 2rem;
  font-size: 1.75rem;
}

.form-signin .form-group {
  margin-bottom: 1.5rem;
}

.form-signin .form-group label {
  display: block;
  color: #94a3b8;
  font-size: 0.95rem;
  font-weight: 500;
  margin-bottom: 0.5rem;
  opacity: 0.7;
  transition: all 0.3s ease;
}

.form-signin .form-group input:focus ~ label,
.form-signin .form-group:focus-within label {
  opacity: 1;
  color: #60a5fa;
}

.form-signin .form-group input {
  width: 100%;
  background-color: rgba(15, 23, 42, 0.6);
  border: 1px solid rgba(59, 130, 246, 0.3);
  color: #f1f5f9;
  padding: 0.875rem 1rem;
  border-radius: 10px;
  transition: all 0.3s ease;
  font-size: 1rem;
}

.form-signin .form-group input:focus {
  background-color: rgba(15, 23, 42, 0.8);
  border-color: #3b82f6;
  box-shadow: 0 0 0 0.25rem rgba(59, 130, 246, 0.15);
  color: #ffffff;
  outline: none;
}

.form-signin .form-group input::placeholder {
  color: #64748b;
  opacity: 0.6;
}

.form-signin .btn-primary {
  background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
  border: none;
  padding: 0.875rem;
  font-weight: 600;
  font-size: 1.05rem;
  border-radius: 10px;
  margin-top: 1rem;
  transition: all 0.3s ease;
  box-shadow: 0 4px 12px rgba(59, 130, 246, 0.4);
}

.form-signin .btn-primary:hover {
  background: linear-gradient(135deg, #2563eb 0%, #1d4ed8 100%);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(59, 130, 246, 0.5);
}

.form-signin .btn-primary:active {
  transform: translateY(0);
  box-shadow: 0 2px 8px rgba(59, 130, 246, 0.4);
}

/* Alert styling */
.alert {
  border-radius: 10px;
  border: none;
  margin-bottom: 1.5rem;
  padding: 1rem;
}

.alert-danger {
  background-color: rgba(239, 68, 68, 0.15);
  color: #fca5a5;
  border-left: 4px solid #ef4444;
}