/* 現代版樣式 - 保留原有功能邏輯 */
.gradient-bg {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  min-height: 100vh;
  padding: 2rem;
}

.form-container {
  background: rgba(255, 255, 255, 0.95);
  border-radius: 20px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  backdrop-filter: blur(10px);
  padding: 2.5rem;
  max-width: 800px;
  margin: 2rem auto;
}

.step-indicator {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 3rem;
}

.step {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  background: #e0e7ff;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #4a6bdf;
  transition: all 0.3s ease;
}

.step.active {
  background: #4a6bdf;
  color: white;
  transform: scale(1.1);
}

.form-step {
  display: none;
  opacity: 0;
  transform: translateY(20px);
  transition: all 0.3s ease;
}

.form-step.active {
  display: block;
  opacity: 1;
  transform: translateY(0);
}

.model-comparison {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}

.model-card {
  background: white;
  border-radius: 15px;
  padding: 1.5rem;
  border: 2px solid #e0e7ff;
  transition: all 0.3s ease;
}

.model-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
}

@media (max-width: 768px) {
  .form-container {
    padding: 1.5rem;
    margin: 1rem;
  }
  
  .btn {
    padding: 0.75rem 1.5rem;
    font-size: 0.9rem;
  }
}

.form-navigation {
  display: flex;
  justify-content: space-between;
  margin-top: 2rem;
  gap: 1rem;
}

.btn-prev, .btn-next {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-submit {
  background: linear-gradient(135deg, #4a6bdf, #667eea);
  border: none;
  transition: all 0.3s ease;
}

.btn-submit:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 12px rgba(74, 107, 223, 0.3);
}


/* 新增標題樣式 */
.form-step h2.text-center {
  color: #4a6bdf;
  font-weight: 700;
  margin-bottom: 1.5rem;
  position: relative;
  display: inline-block;
}

.form-step h2.text-center::after {
  content: '';
  position: absolute;
  bottom: -10px;
  left: 50%;
  transform: translateX(-50%);
  width: 50px;
  height: 3px;
  background: linear-gradient(135deg, #4a6bdf, #667eea);
  border-radius: 3px;
}

/* Success Modal */
.success-modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    animation: fadeIn 0.3s ease-out;
}

.success-modal .modal-content {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    text-align: center;
    max-width: 400px;
    width: 90%;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}

.success-modal i.fas {
    font-size: 3rem;
    color: #28a745;
    margin-bottom: 1rem;
}

.success-modal h3 {
    margin-bottom: 1rem;
    color: #2c3e50;
    font-weight: 600;
}

.success-modal p {
    color: #666;
    margin-bottom: 1.5rem;
}

.modal-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* Info Toast */
.info-toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: #17a2b8;
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    animation: slideIn 0.3s ease-out;
}

.info-toast i.fas {
    font-size: 1.2rem;
}

.info-toast.fade-out {
    animation: fadeOut 0.3s ease-out forwards;
}

/* Error Toast */
.error-toast {
    position: fixed;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    background: #dc3545;
    color: white;
    padding: 1rem 1.5rem;
    border-radius: 8px;
    display: flex;
    align-items: center;
    gap: 0.8rem;
    z-index: 1000;
    box-shadow: 0 4px 12px rgba(0,0,0,0.15);
    animation: slideIn 0.3s ease-out;
}

.error-toast i.fas {
    font-size: 1.2rem;
}

.error-toast.fade-out {
    animation: fadeOut 0.3s ease-out forwards;
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideIn {
    from { 
        bottom: -50px; 
        opacity: 0; 
    }
    to { 
        bottom: 20px; 
        opacity: 1; 
    }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

/* Model card selection */
.model-card.selected {
    border: 2px solid #4a6bdf;
    background-color: #f8f9ff;
    transform: translateY(-5px);
}

/* Form validation */
.is-invalid {
    border-color: #dc3545 !important;
}

.invalid-feedback {
    color: #dc3545;
    font-size: 0.85rem;
    margin-top: 0.25rem;
}

.was-validated .form-control:invalid {
    border-color: #dc3545;
}