:root {
     --primary: #003366;
     --accent: #D4AF37;
     --success: #28a745;
     --bg-light: #f4f7f9;
 }

 body {
     font-family: 'Open Sans', sans-serif;
     background-color: var(--bg-light);
     background-image: url('https://www.transparenttextures.com/patterns/cubes.png');
     overflow-x: hidden;
 }

 h1,
 h2,
 h3,
 .btn-pay {
     font-family: 'Montserrat', sans-serif;
 }

 /* --- RESPONSIVE HEADER START --- */
 .navbar-custom {
     background: white;
     box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
     padding: 15px 0;
     margin-bottom: 40px;
 }

 .header-container {
     display: flex;
     align-items: center;
     justify-content: space-between;
     gap: 15px;
 }

 .header-logo img {
     height: 90px;
     width: auto;
     object-fit: contain;
 }

 .school-title {
     color: var(--primary);
     font-weight: 800;
     /* Fluid font size: scales between 18px and 22px */
     font-size: clamp(1.1rem, 4vw, 1.4rem);
     text-transform: uppercase;
     letter-spacing: 0.5px;
     margin: 0;
     text-align: center;
     line-height: 1.2;
 }

 @media (max-width: 576px) {
     .header-container {
         flex-wrap: wrap;
         justify-content: center;
     }

     .header-logo {
         flex: 0 0 auto;
     }

     .header-text-wrapper {
         flex: 0 0 100%;
         order: 3;
         /* Move text below the two logos on mobile */
         margin-top: 5px;
     }

     .header-logo img {
         height: 80px;
         /* Slightly smaller logos on mobile */
     }
 }

 /* --- RESPONSIVE HEADER END --- */

 .page-wrapper {
     min-height: 100vh;
     display: flex;
     flex-direction: column;
 }

 .top-gradient {
     height: 300px;
     background: linear-gradient(135deg, var(--primary) 0%, #00509d 100%);
     position: absolute;
     top: 0;
     width: 100%;
     z-index: -1;
     border-bottom-left-radius: 50% 20px;
     border-bottom-right-radius: 50% 20px;
 }

 .main-card {
     background: rgba(255, 255, 255, 0.95);
     backdrop-filter: blur(10px);
     border: none;
     border-radius: 20px;
     box-shadow: 0 20px 40px rgba(0, 0, 0, 0.12);
     overflow: hidden;
     margin-bottom: 50px;
 }

 .card-sidebar {
     background: var(--primary);
     color: white;
     padding: 40px;
     display: flex;
     flex-direction: column;
     justify-content: center;
     background-image: linear-gradient(rgba(0, 51, 102, 0.9), rgba(0, 51, 102, 0.9)), url('https://images.unsplash.com/photo-1541534741688-6078c6bfb5c5?auto=format&fit=crop&q=80&w=500');
     background-size: cover;
 }

 .form-content {
     padding: 40px;
 }

 .form-label {
     font-weight: 600;
     font-size: 0.85rem;
     color: #555;
     margin-bottom: 6px;
 }

 .form-control,
 .form-select {
     border: 2px solid #edf2f7;
     border-radius: 10px;
     padding: 12px 15px;
     font-size: 0.95rem;
     transition: all 0.3s ease;
 }

 .step-tag {
     background: var(--accent);
     color: var(--primary);
     padding: 4px 12px;
     border-radius: 20px;
     font-size: 0.7rem;
     font-weight: 700;
     text-transform: uppercase;
     margin-bottom: 10px;
     display: inline-block;
 }

 .fee-display-container {
     background: #f8faff;
     border: 2px dashed #cbd5e0;
     border-radius: 15px;
     padding: 20px;
     text-align: center;
     margin: 30px 0;
 }

 .fee-amount {
     font-size: 2.5rem;
     font-weight: 800;
     color: var(--primary);
 }

 .btn-pay {
     background: linear-gradient(to right, #003366, #00509d);
     color: white;
     border: none;
     padding: 18px;
     border-radius: 12px;
     font-weight: 700;
     font-size: 1.1rem;
     letter-spacing: 1px;
     transition: all 0.4s;
     box-shadow: 0 10px 20px rgba(0, 51, 102, 0.2);
 }

 .btn-pay:hover {
     transform: translateY(-3px);
     box-shadow: 0 15px 25px rgba(0, 51, 102, 0.3);
     color: white;
 }

 footer {
     background: white;
     padding: 30px 0;
     border-top: 1px solid #e2e8f0;
     margin-top: auto;
 }

 @media (max-width: 991px) {
     .card-sidebar {
         padding: 30px;
         text-align: center;
     }

     .form-content {
         padding: 30px 20px;
     }
 }