:root {
      --primary: #7C3AED;
      --primary-light: #8B5CF6;
      --secondary: #EC4899;
      --accent: #06B6D4;
      --dark: #1F2937;
      --light: #F9FAFB;
      --gray: #6B7280;
      --success: #10B981;
      --border-radius: 16px;
      --shadow: 0 10px 25px rgba(0, 0, 0, 0.05);
      --transition: all 0.3s ease;
    }
    
    body {
      font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      color: var(--dark);
      background: linear-gradient(135deg, #F0F4FF 0%, #FDF2F8 100%);
      line-height: 1.6;
      min-height: 100vh;
    }
    
    .container {
      max-width: 1200px;
    }
    
    /* Header Styles */
    .main-header {
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      color: white;
      padding: 3rem 0;
      border-radius: 0 0 var(--border-radius) var(--border-radius);
      margin-bottom: 2rem;
      box-shadow: var(--shadow);
      position: relative;
      overflow: hidden;
    }
    
    .main-header::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      bottom: 0;
      background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.1'%3E%3Ccircle cx='30' cy='30' r='4'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    }
    
    .main-header h1 {
      font-weight: 800;
      margin-bottom: 0.5rem;
      font-size: 2.5rem;
    }
    
    .main-header p {
      font-size: 1.1rem;
      opacity: 0.9;
      max-width: 600px;
      margin: 0 auto;
    }
    
    /* Card Styles */
    .feature-card {
      background: white;
      border-radius: var(--border-radius);
      box-shadow: var(--shadow);
      padding: 2.5rem;
      margin-bottom: 2rem;
      transition: var(--transition);
      border: none;
      position: relative;
      overflow: hidden;
    }
    
    .feature-card::before {
      content: '';
      position: absolute;
      top: 0;
      left: 0;
      width: 5px;
      height: 100%;
      background: linear-gradient(to bottom, var(--primary), var(--secondary));
    }
    
    .feature-card:hover {
      transform: translateY(-5px);
      box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
    }
    
    .card-title {
      color: var(--primary);
      font-weight: 700;
      margin-bottom: 1.5rem;
      display: flex;
      align-items: center;
      font-size: 1.5rem;
    }
    
    .card-title i {
      margin-right: 10px;
      font-size: 1.5rem;
      background: linear-gradient(135deg, var(--primary), var(--secondary));
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    
    /* Upload Area */
    .upload-area {
      border: 2px dashed #D1D5DB;
      border-radius: var(--border-radius);
      padding: 2.5rem 1rem;
      text-align: center;
      background-color: #F9FAFB;
      transition: var(--transition);
      cursor: pointer;
      margin-bottom: 1.5rem;
      position: relative;
    }
    
    .upload-area:hover {
      border-color: var(--primary-light);
      background-color: #F3F4F6;
    }
    
    .upload-area.active {
      border-color: var(--primary);
      background-color: #EDE9FE;
    }
    
    .upload-icon {
      font-size: 3rem;
      color: var(--primary-light);
      margin-bottom: 1rem;
    }
    
    .upload-text {
      margin-bottom: 1rem;
    }
    
    .upload-text h4 {
      color: var(--dark);
      margin-bottom: 0.5rem;
      font-weight: 600;
    }
    
    .upload-text p {
      color: var(--gray);
      font-size: 0.9rem;
    }
    
    .btn-primary-custom {
      background: linear-gradient(135deg, var(--primary), var(--primary-light));
      border: none;
      border-radius: 50px;
      padding: 0.8rem 2rem;
      font-weight: 600;
      color: white;
      transition: var(--transition);
      box-shadow: 0 4px 10px rgba(124, 58, 237, 0.3);
      position: relative;
      overflow: hidden;
    }
    
    .btn-primary-custom:hover {
      transform: translateY(-2px);
      box-shadow: 0 6px 15px rgba(124, 58, 237, 0.4);
      color: white;
    }
    
    .btn-primary-custom:active {
      transform: translateY(0);
    }
    
    /* Form Styles */
    .form-group {
      margin-bottom: 1.5rem;
      position: relative;
    }
    
    .form-label {
      font-weight: 600;
      margin-bottom: 0.5rem;
      color: var(--dark);
      display: flex;
      align-items: center;
    }
    
    .form-label i {
      margin-right: 8px;
      color: var(--primary);
    }
    
    .form-control {
      border-radius: 10px;
      border: 1px solid #E5E7EB;
      padding: 0.75rem 1rem;
      transition: var(--transition);
      background: #F9FAFB;
    }
    
    .form-control:focus {
      border-color: var(--primary-light);
      box-shadow: 0 0 0 3px rgba(124, 58, 237, 0.1);
      background: white;
    }
    
    .range-container {
      display: flex;
      align-items: center;
    }
    
    .range-value {
      margin-left: 10px;
      font-weight: 600;
      color: var(--primary);
      min-width: 30px;
    }
    
    /* Custom Range Slider */
    .form-control-range {
      width: 100%;
      height: 8px;
      border-radius: 10px;
      background: #E5E7EB;
      outline: none;
      -webkit-appearance: none;
    }
    
    .form-control-range::-webkit-slider-thumb {
      -webkit-appearance: none;
      width: 20px;
      height: 20px;
      border-radius: 50%;
      background: var(--primary);
      cursor: pointer;
      box-shadow: 0 2px 5px rgba(0, 0, 0, 0.2);
      transition: var(--transition);
    }
    
    .form-control-range::-webkit-slider-thumb:hover {
      background: var(--primary-light);
      transform: scale(1.1);
    }
    
    /* Preview Section */
    .preview-section {
      background: white;
      border-radius: var(--border-radius);
      box-shadow: var(--shadow);
      padding: 1.5rem;
      margin-top: 2rem;
      border-left: 4px solid var(--accent);
    }
    
    .preview-title {
      font-weight: 600;
      margin-bottom: 1rem;
      color: var(--dark);
      display: flex;
      align-items: center;
    }
    
    .preview-title i {
      margin-right: 8px;
      color: var(--accent);
    }
    
    .preview-box {
      border: 1px solid #E5E7EB;
      border-radius: 8px;
      height: 200px;
      display: flex;
      align-items: center;
      justify-content: center;
      background-color: #F9FAFB;
      position: relative;
      overflow: hidden;
    }
    
    .preview-watermark {
      position: absolute;
      opacity: 0.5;
      font-size: 2rem;
      color: var(--primary);
      transform: rotate(-45deg);
      pointer-events: none;
      font-weight: 600;
    }
    
    /* File List */
    .file-list {
      margin-top: 1.5rem;
    }
    
    .file-item {
      display: flex;
      align-items: center;
      padding: 0.75rem 1rem;
      background: #F9FAFB;
      border-radius: 8px;
      margin-bottom: 0.5rem;
      transition: var(--transition);
      border-left: 3px solid var(--primary);
    }
    
    .file-item:hover {
      background: #F3F4F6;
      transform: translateX(5px);
    }
    
    .file-item i {
      color: var(--primary);
      margin-right: 10px;
    }
    
    .file-name {
      flex-grow: 1;
      font-weight: 500;
    }
    
    .file-remove {
      color: var(--gray);
      cursor: pointer;
      transition: var(--transition);
    }
    
    .file-remove:hover {
      color: var(--secondary);
    }
    
    /* Tab Navigation */
    .nav-tabs {
      border-bottom: 2px solid #E5E7EB;
      margin-bottom: 2rem;
    }
    
    .nav-tabs .nav-link {
      border: none;
      padding: 1rem 1.5rem;
      font-weight: 600;
      color: var(--gray);
      border-radius: var(--border-radius) var(--border-radius) 0 0;
      transition: var(--transition);
      position: relative;
    }
    
    .nav-tabs .nav-link.active {
      color: var(--primary);
      background-color: transparent;
    }
    
    .nav-tabs .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -2px;
      left: 0;
      width: 100%;
      height: 3px;
      background: linear-gradient(to right, var(--primary), var(--secondary));
      border-radius: 3px 3px 0 0;
    }
    
    .nav-tabs .nav-link:hover {
      color: var(--primary);
      border-color: transparent;
    }
    
    /* Footer */
    .footer {
      background: var(--dark);
      color: white;
      padding: 3rem 0;
      margin-top: 4rem;
      border-radius: var(--border-radius) var(--border-radius) 0 0;
    }
    
    /* Responsive */
    @media (max-width: 768px) {
      .feature-card {
        padding: 1.5rem;
      }
      
      .upload-area {
        padding: 1.5rem 1rem;
      }
      
      .main-header h1 {
        font-size: 2rem;
      }
    }
    
    /* Animation for elements */
    @keyframes fadeInUp {
      from {
        opacity: 0;
        transform: translateY(20px);
      }
      to {
        opacity: 1;
        transform: translateY(0);
      }
    }
    
    .fade-in-up {
      animation: fadeInUp 0.5s ease forwards;
    }
    
    /* Loading Spinner */
    .spinner-border {
      width: 1.5rem;
      height: 1.5rem;
    }
    
    .btn-loading .spinner-border {
      display: inline-block;
    }