:root {
     --primary: #1a365d;
     --secondary: #2c5282;
     --accent: #e2b979;
     --light: #f7fafc;
     --dark: #2d3748;
     --success: #48bb78;
     --warning: #ed8936;
     --error: #e53e3e;
 }

 body {
     font-family: 'Georgia', 'Times New Roman', serif;
     background-color: #f5f7fa;
     color: var(--dark);
     line-height: 1.6;
     padding-top: 2rem;
     padding-bottom: 2rem;
 }

 .container {
     max-width: 1000px;
     margin: 0 auto;
     padding: 2rem;
 }

 @media (max-width: 768px) {
     .container {
         padding: 1rem;
     }

     body {
         padding-top: 1rem;
         padding-bottom: 1rem;
     }
 }

 @media (max-width: 576px) {
     .container {
         padding: 0.75rem;
     }

     select,
     input {
         padding: 0.7rem;
         font-size: 0.95rem;
     }

     label {
         font-size: 0.95rem;
         margin-bottom: 0.4rem;
     }

     .back-link {
         font-size: 0.9rem;
         margin-bottom: 0.75rem;
     }

     .form-group {
         margin-bottom: 1.25rem;
     }

     .cascading-dropdown .form-control {
         height: 42px;
     }

     .invalid-feedback {
         font-size: 0.8rem;
     }

     .city-item {
         width: 33.33%;
         padding: 6px 8px;
         font-size: 0.9rem;
     }
 }

 .header {
     background: linear-gradient(135deg, var(--primary), var(--secondary));
     color: white;
     padding: 2rem;
     border-radius: 0.5rem;
     margin-bottom: 2rem;
     box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
     position: relative;
     overflow: hidden;
 }

 .header::before {
     content: "";
     position: absolute;
     top: 0;
     right: 0;
     bottom: 0;
     left: 0;
     background: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="100" height="100" viewBox="0 0 100 100"><text x="10" y="50" font-family="Georgia" font-size="20" fill="rgba(255,255,255,0.05)">⚖</text></svg>');
     opacity: 0.1;
 }

 .header h1 {
     font-size: 2.5rem;
     margin-bottom: 0.5rem;
     font-weight: 700;
     position: relative;
 }

 .header p {
     font-size: 1.1rem;
     opacity: 0.9;
     max-width: 80%;
     position: relative;
 }

 .calculator-container {
     grid-template-columns: 1fr 1fr;
     gap: 2rem;
     margin-bottom: 2rem;
 }

 @media (max-width: 768px) {
     .calculator-container {
         grid-template-columns: 1fr;
         gap: 1.5rem;
         margin-bottom: 1.5rem;
     }

     .form-section,
     .result-section {
         padding: 1.5rem;
     }

     .result-section {
         margin-top: 3rem;
     }

     .header {
         padding: 1.5rem;
         margin-bottom: 1.5rem;
     }

     .header h1 {
         font-size: 2rem;
     }
 }

 .form-section,
 .result-section {
     background: white;
     border-radius: 0.5rem;
     padding: 2rem;
     box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
 }

 .section-title {
     font-size: 1.5rem;
     color: var(--primary);
     margin-bottom: 1.5rem;
     padding-bottom: 0.5rem;
     border-bottom: 2px solid var(--accent);
     display: flex;
     align-items: center;
 }

 .section-title i {
     margin-right: 0.75rem;
     color: var(--accent);
 }

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

 label {
     display: block;
     margin-bottom: 0.5rem;
     font-weight: 600;
     color: var(--secondary);
 }

 select,
 input {
     width: 100%;
     padding: 0.75rem;
     border: 1px solid #e2e8f0;
     border-radius: 0.375rem;
     font-size: 1rem;
     transition: all 0.2s;
 }

 select:focus,
 input:focus {
     outline: none;
     border-color: var(--accent);
     box-shadow: 0 0 0 3px rgba(226, 185, 121, 0.3);
 }

 button {
     background: linear-gradient(to right, var(--primary), var(--secondary));
     color: white;
     border: none;
     padding: 0.75rem 1.5rem;
     font-size: 1rem;
     border-radius: 0.375rem;
     cursor: pointer;
     transition: all 0.3s;
     font-weight: 600;
     width: 100%;
     margin-top: 1rem;
 }

 button:hover {
     transform: translateY(-2px);
     box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
 }

 .result-card {
     background: white;
     border-radius: 0.5rem;
     padding: 1.5rem;
     margin-bottom: 1.5rem;
     box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
     border-left: 4px solid var(--accent);
 }

 .result-title {
     font-size: 1.25rem;
     color: var(--primary);
     margin-bottom: 1rem;
     display: flex;
     align-items: center;
 }

 .result-title i {
     margin-right: 0.5rem;
     color: var(--accent);
 }

 .result-value {
     font-size: 2rem;
     font-weight: 700;
     color: var(--secondary);
     margin: 0.5rem 0;
 }

 .result-details {
     margin-top: 1rem;
     font-size: 0.9rem;
     color: #718096;
 }

 .fee-breakdown {
     width: 100%;
     border-collapse: collapse;
     margin-top: 1rem;
 }

 .fee-breakdown th,
 .fee-breakdown td {
     padding: 0.75rem;
     text-align: left;
     border-bottom: 1px solid #e2e8f0;
 }

 .fee-breakdown th {
     background-color: #f7fafc;
     color: var(--primary);
     font-weight: 600;
 }

 .legal-note {
     font-size: 0.85rem;
     color: #718096;
     margin-top: 2rem;
     padding: 1rem;
     background-color: #f7fafc;
     border-radius: 0.375rem;
     border-left: 3px solid var(--accent);
 }

 .footer {
     text-align: center;
     margin-top: 3rem;
     padding: 1.5rem;
     color: #718096;
     font-size: 0.9rem;
     border-top: 1px solid #e2e8f0;
 }

 .animate-fade-in {
     animation: fadeIn 0.5s ease-in-out;
 }

 @keyframes fadeIn {
     from {
         opacity: 0;
         transform: translateY(10px);
     }

     to {
         opacity: 1;
         transform: translateY(0);
     }
 }

 .header-top-nav {
     position: relative;
     z-index: 5;
     margin-bottom: 10px;
 }

 .back-link {
     display: inline-block;
     margin-bottom: 1rem;
     color: white;
     text-decoration: none;
     font-weight: 600;
     transition: all 0.2s;
     padding: 5px 10px;
     border-radius: 4px;
 }

 .back-link:hover {
     color: var(--accent);
     text-decoration: underline;
 }

 .back-link i {
     margin-right: 0.5rem;
 }

 /* 地点选择器样式 */
 .location-selector {
     position: relative;
 }

 .location-selector .form-control {
     cursor: pointer;
     background-color: #fff;
 }

 .location-modal {
     display: none;
     position: fixed;
     top: 0;
     left: 0;
     width: 100%;
     height: 100%;
     background-color: rgba(0, 0, 0, 0.5);
     z-index: 1000;
     justify-content: center;
     align-items: center;
 }

 .location-modal-content {
     background-color: #fff;
     width: 90%;
     max-width: 750px;
     max-height: 80vh;
     border-radius: 8px;
     box-shadow: 0 5px 15px rgba(0, 0, 0, 0.3);
     overflow: hidden;
     display: flex;
     flex-direction: column;
 }

 .location-modal-header {
     padding: 15px 20px;
     border-bottom: 1px solid #e1e1e1;
     display: flex;
     justify-content: space-between;
     align-items: center;
     background-color: #fff;
 }

 .location-modal-header h3 {
     margin: 0;
     font-size: 1.25rem;
     color: #333;
 }

 .location-modal-close {
     background: none;
     border: none;
     font-size: 1.5rem;
     color: #333;
     cursor: pointer;
     width: 32px;
     height: 32px;
     display: flex;
     align-items: center;
     justify-content: center;
     border-radius: 50%;
     transition: background-color 0.2s, transform 0.2s;
 }

 .location-modal-close:hover {
     color: var(--accent);
     box-shadow: none;
 }

 .location-search {
     padding: 10px 20px;
     border-bottom: 1px solid #e1e1e1;
     position: relative;
 }

 .location-search input {
     width: 100%;
     padding: 8px 12px;
     border: 1px solid #e1e1e1;
     border-radius: 4px;
     font-size: 14px;
     padding-left: 30px;
     transition: border-color 0.2s, box-shadow 0.2s;
 }

 .location-search input:focus {
     border-color: var(--accent);
     box-shadow: 0 0 0 3px rgba(226, 185, 121, 0.2);
     outline: none;
 }

 .location-search .search-icon {
     position: absolute;
     left: 30px;
     top: 19px;
     color: #999;
 }

 .location-modal-body {
     display: flex;
     height: 450px;
     overflow: hidden;
 }

 .alphabet-list {
     width: 80px;
     background: #f7f7f7;
     display: flex;
     flex-wrap: wrap;
     justify-content: center;
     overflow-y: auto;
     padding: 10px 5px;
 }

 .alphabet-item {
     width: 24px;
     height: 24px;
     margin: 2px;
     display: flex;
     justify-content: center;
     align-items: center;
     color: #666;
     font-weight: bold;
     cursor: pointer;
     border-radius: 3px;
 }

 .alphabet-item:hover,
 .alphabet-item.active {
     color: white;
     background-color: var(--accent);
 }

 .city-container {
     flex: 1;
     overflow-y: auto;
     padding: 0 15px;
 }

 .city-section {
     margin-bottom: 20px;
 }

 .city-section-header {
     padding: 10px 10px;
     font-size: 16px;
     font-weight: bold;
     color: #333;
     position: sticky;
     top: 0;
     background: #fff;
     border-bottom: 1px solid #eee;
 }

 .city-grid {
     display: flex;
     flex-wrap: wrap;
     padding: 10px;
 }

 .city-item {
     width: 25%;
     padding: 8px 10px;
     cursor: pointer;
     font-size: 14px;
     color: #333;
     transition: all 0.2s;
     border-radius: 4px;
     position: relative;
     overflow: hidden;
 }

 .city-item:hover {
     color: var(--primary);
     background-color: rgba(0, 0, 0, 0.05);
 }

 .city-item.selected {
     color: white;
     background-color: var(--accent);
     font-weight: bold;
     box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
 }

 .city-item.selected::after {
     content: "✓";
     position: absolute;
     right: 10px;
     font-weight: bold;
 }

 .city-item.highlighted {
     background-color: rgba(226, 185, 121, 0.2);
     border: 1px dashed var(--accent);
 }

 /* 添加响应式布局 */
 @media (max-width: 768px) {
     .city-item {
         width: 33.33%;
     }
 }

 @media (max-width: 576px) {
     .city-item {
         width: 50%;
     }

     .alphabet-list {
         width: 60px;
     }
 }

 /* 级联选择器样式优化 */
 .cascading-dropdown {
     position: relative;
 }

 .cascading-dropdown .form-control {
     cursor: pointer;
 }

 .cascading-dropdown .invalid-feedback {
     display: none;
 }

 .cascading-dropdown .form-control.is-invalid {
     border-color: #dc3545;
     background-image: url("data:image/svg+xml,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 12 12' width='12' height='12' fill='none' stroke='%23dc3545'%3e%3ccircle cx='6' cy='6' r='4.5'/%3e%3cpath stroke-linejoin='round' d='M5.8 3.6h.4L6 6.5z'/%3e%3ccircle cx='6' cy='8.2' r='.6' fill='%23dc3545' stroke='none'/%3e%3c/svg%3e");
     background-repeat: no-repeat;
     background-position: right calc(0.375em + 0.1875rem) center;
     background-size: calc(0.75em + 0.375rem) calc(0.75em + 0.375rem);
 }

 .cascading-dropdown .form-control.is-invalid+div+input+input+.invalid-feedback {
     display: block;
     width: 100%;
     margin-top: 0.25rem;
     font-size: 0.875em;
     color: #dc3545;
 }

 .cascading-menu {
     position: absolute;
     top: 100%;
     left: 0;
     right: 0;
     background-color: white;
     box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
     border-radius: 0.375rem;
     display: none;
     z-index: 1000;
     overflow: hidden;
     margin-top: 5px;
     display: none;
     flex-direction: row;
     border: 1px solid #e2e8f0;
 }

 .cascading-menu.show {
     display: flex;
 }

 .category-menu {
     width: 40%;
     border-right: 1px solid #e2e8f0;
     max-height: 300px;
     overflow-y: auto;
 }

 .subcategory-menu {
     width: 60%;
     max-height: 100%;
     overflow-y: auto;
 }

 .category-item,
 .subcategory-item {
     padding: 12px 15px;
     cursor: pointer;
     transition: all 0.2s;
     color: #333;
     border-bottom: 1px solid #f0f0f0;
     position: relative;
     font-size: 14px;
 }

 .category-item {
     display: flex;
     justify-content: space-between;
     align-items: center;
     background-color: #f9f9f9;
 }

 .category-item::after {
     content: '›';
     color: #aaa;
     font-size: 20px;
     font-weight: bold;
     position: absolute;
     right: 12px;
     top: 50%;
     transform: translateY(-50%);
 }

 .category-item:hover,
 .subcategory-item:hover {
     background-color: #f0f7ff;
 }

 .category-item.active {
     background-color: #e6f0ff;
     color: var(--primary);
     font-weight: 500;
 }

 .category-item.active::after {
     color: var(--primary);
 }

 .subcategory-item.active {
     color: var(--accent);
     background-color: #fdf8ef;
     font-weight: 500;
 }

 /* 模态背景 - 默认隐藏 */
 .modal-backdrop {
     display: none;
 }

 .modal-backdrop.show {
     display: none;
 }

 /* 移动端优化样式 */
 @media (max-width: 768px) {
     .cascading-menu {
         position: fixed;
         top: auto;
         bottom: 0;
         left: 0;
         right: 0;
         margin: 0;
         height: 50vh;
         max-height: 420px;
         border-radius: 12px 12px 0 0;
         box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
         z-index: 1050;
     }

     .cascading-menu::before {
         content: '';
         position: absolute;
         top: 8px;
         left: 50%;
         transform: translateX(-50%);
         width: 40px;
         height: 4px;
         background-color: #ddd;
         border-radius: 4px;
     }

     .category-menu {
         width: 40%;
         border-top: 12px solid white;
     }

     .subcategory-menu {
         width: 60%;
         border-top: 12px solid white;
     }

     .category-item,
     .subcategory-item {
         padding: 14px 15px;
         font-size: 15px;
     }

     /* 移动端的模态背景 */
     .modal-backdrop {
         position: fixed;
         top: 0;
         left: 0;
         right: 0;
         bottom: 0;
         background-color: rgba(0, 0, 0, 0.5);
         z-index: 1040;
     }

     .modal-backdrop.show {
         display: block;
     }
 }

 /* 超小屏幕优化 */
 @media (max-width: 380px) {
     .cascading-menu {
         height: 60vh;
     }

     .category-item,
     .subcategory-item {
         padding: 12px 10px;
         font-size: 14px;
     }
 }

 /* Apple风格表格样式 */
 .apple-style-container {
     background-color: #fff;
     border-radius: 12px;
     box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
     overflow: hidden;
     margin: 1.5rem 0;
     transition: all 0.3s ease;
 }

 .apple-style-table {
     width: 100%;
     border-collapse: separate;
     border-spacing: 0;
     font-size: 0.95rem;
 }

 .apple-style-table thead {
     background-color: #f6f9fc;
 }

 .apple-style-table th {
     padding: 16px 13px;
     text-align: left;
     font-weight: 500;
     color: #606f7b;
     border-bottom: 1px solid #e6ebf1;
     letter-spacing: 0.05em;
     font-size: 0.85rem;
     text-transform: uppercase;
 }

 .apple-style-table tbody tr {
     transition: background-color 0.2s;
 }

 .apple-style-table tbody tr:hover {
     background-color: #f8f9ff;
 }

 .apple-style-table td {
     padding: 14px 20px;
     vertical-align: middle;
     border-bottom: 1px solid #edf2f7;
     color: #3d4852;
 }

 .apple-style-table tbody tr:last-child td {
     border-bottom: none;
 }

 .apple-style-table td:nth-child(3) {
     font-weight: 600;
     color: var(--primary);
 }

 .apple-style-table td:nth-child(4) {
     color: #718096;
     font-size: 0.9rem;
 }

 .apple-style-table tbody tr:last-child td {
     border-bottom: none;
 }

 .apple-style-legend {
     padding: 16px 20px;
     background-color: #f9fafb;
     border-top: 1px solid #edf2f7;
 }

 .legend-item {
     display: flex;
     align-items: center;
     font-size: 0.85rem;
     color: #64748b;
 }

 .legend-item i {
     margin-right: 8px;
 }

 /* Apple风格标题样式 */
 .apple-style-header {
     padding: 22px 24px;
     background-color: #fff;
     border-bottom: 1px solid #f1f5f9;
 }

 .apple-style-header h3 {
     font-size: 1.5rem;
     font-weight: 500;
     color: #1a365d;
     margin: 0 0 8px 0;
     letter-spacing: -0.02em;
 }

 .apple-style-subtitle {
     display: flex;
     align-items: center;
     margin-top: 8px;
     color: #64748b;
     font-size: 0.9rem;
 }

 .apple-style-subtitle .badge {
     font-weight: 500;
     letter-spacing: 0.02em;
     padding: 5px 10px;
     border-radius: 20px;
 }

 /* 全国标准徽章样式 */
 .badge.bg-warning {
     background-color: #ffc107 !important;
     color: #212529;
     font-size: 0.75rem;
     padding: 0.35em 0.65em;
     font-weight: 500;
     border-radius: 0.25rem;
     display: inline-block;
     line-height: 1;
     text-align: center;
     white-space: nowrap;
     vertical-align: baseline;
 }

 /* 全国标准提示样式 */
 .national-standard-notice {
     background-color: rgba(255, 193, 7, 0.1);
     padding: 8px 12px;
     border-radius: 6px;
     border-left: 3px solid #ffc107;
 }

 .national-standard-notice i {
     color: #ffc107;
 }

 .national-standard-notice strong {
     color: #212529;
 }

 /* 移动端 Apple 风格卡片视图 */
 .apple-style-cards {
     display: none;
 }

 .apple-style-card {
     background-color: white;
     border-radius: 12px;
     box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
     margin-bottom: 12px;
     overflow: hidden;
     transition: all 0.2s ease;
 }

 .apple-style-card:active {
     transform: scale(0.98);
 }

 .apple-style-card-header {
     padding: 16px;
     border-bottom: 1px solid #f1f5f9;
 }

 .apple-style-card-title {
     font-weight: 600;
     font-size: 1.1rem;
     color: var(--primary);
     margin: 0;
 }

 .apple-style-card-body {
     padding: 0;
 }

 .apple-style-card-row {
     display: flex;
     padding: 12px 16px;
     border-bottom: 1px solid #f5f7fa;
 }

 .apple-style-card-row:last-child {
     border-bottom: none;
 }

 .apple-style-card-label {
     width: 30%;
     color: #64748b;
     font-size: 0.9rem;
 }

 .apple-style-card-value {
     width: 70%;
     font-weight: 500;
     color: #334155;
 }

 .apple-style-card-value.unit-value {
     font-size: 1.2rem;
 }

 .apple-style-card-price {
     font-weight: 600;
     color: var(--primary);
 }

 .apple-style-card-remark {
     font-size: 0.85rem;
     color: #64748b;
     padding: 0 16px 16px;
     line-height: 1.5;
 }

 /* 响应式调整 */
 @media (max-width: 768px) {
     .apple-style-table {
         display: none;
     }

     .apple-style-cards {
         display: block;
         margin-top: 1rem;
     }

     .apple-style-table th,
     .apple-style-table td {
         padding: 12px 14px;
     }

     .apple-style-table th:last-child,
     .apple-style-table td:last-child {
         max-width: 140px;
     }

     .apple-style-header {
         padding: 18px 20px;
     }

     .apple-style-header h3 {
         font-size: 1.3rem;
     }
 }

 @media (max-width: 576px) {
     .apple-style-table {
         font-size: 0.85rem;
     }

     .apple-style-cards {
         margin-top: 0.75rem;
     }

     .apple-style-card {
         margin-bottom: 10px;
     }

     .apple-style-card-header {
         padding: 14px;
     }

     .apple-style-card-title {
         font-size: 1rem;
     }

     .apple-style-card-row {
         padding: 10px 14px;
     }

     .apple-style-table th,
     .apple-style-table td {
         padding: 10px 12px;
     }

     .apple-style-table th:last-child,
     .apple-style-table td:last-child {
         max-width: 100px;
     }

     .apple-style-header h3 {
         font-size: 1.2rem;
     }

     .fee-breakdown th,
     .fee-breakdown td {
         padding: 0.6rem;
         font-size: 0.9rem;
     }

     .fee-breakdown {
         margin-top: 0.75rem;
     }

     .result-details {
         font-size: 0.85rem;
         margin-top: 0.75rem;
     }

     .footer {
         margin-top: 2rem;
         padding: 1rem;
         font-size: 0.8rem;
     }

     .apple-style-legend {
         padding: 12px 15px;
         font-size: 0.8rem;
     }

     .apple-style-legend .legend-item.mt-2 {
         margin-top: 0.5rem !important;
         padding-top: 0.5rem;
         border-top: 1px dashed #e2e8f0;
     }

     .badge.bg-warning {
         font-size: 0.7rem;
         padding: 0.25em 0.5em;
     }

     .apple-style-container {
         margin: 1rem 0;
         border-radius: 8px;
     }

     .alert {
         padding: 0.75rem;
         margin-bottom: 1rem;
         font-size: 0.9rem;
     }

     .alert-heading {
         font-size: 1.1rem;
         margin-bottom: 0.5rem;
     }

     .alert hr {
         margin: 0.5rem 0;
     }
 }

 @media (max-width: 576px) {
     .calculator-container {
         gap: 1rem;
     }

     .form-section,
     .result-section {
         padding: 1.25rem;
         border-radius: 0.375rem;
     }

     .section-title {
         font-size: 1.3rem;
         margin-bottom: 1.25rem;
         padding-bottom: 0.4rem;
     }

     .form-group {
         margin-bottom: 1.25rem;
     }

     .result-card {
         padding: 1.25rem;
         margin-bottom: 1rem;
         border-radius: 0.375rem;
     }

     .result-title {
         font-size: 1.1rem;
         margin-bottom: 0.75rem;
     }

     .result-value {
         font-size: 1.75rem;
     }

     .legal-note {
         margin-top: 1.5rem;
         padding: 0.75rem;
     }

     .header h1 {
         font-size: 1.75rem;
     }

     .header p {
         font-size: 1rem;
         max-width: 100%;
     }

     button {
         padding: 0.7rem 1rem;
     }

     .location-modal-content {
         width: 95%;
         max-height: 85vh;
     }

     .location-modal-header {
         padding: 12px 15px;
     }

     .location-modal-header h3 {
         font-size: 1.1rem;
     }

     .location-search {
         padding: 8px 15px;
     }

     .location-search input {
         padding: 6px 10px 6px 28px;
         font-size: 0.9rem;
     }

     .location-search .search-icon {
         left: 25px;
         top: 17px;
     }

     .location-modal-body {
         height: 400px;
     }
 }

 /* 回到顶部按钮样式 */
 .back-to-top {
     position: fixed;
     bottom: 20px;
     right: 20px;
     background-color: var(--primary);
     color: white;
     width: 50px;
     height: 50px;
     border-radius: 50%;
     display: flex;
     justify-content: center;
     align-items: center;
     cursor: pointer;
     box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
     transition: all 0.3s;
     opacity: 0;
     visibility: hidden;
     z-index: 1000;
 }

 .back-to-top.visible {
     opacity: 1;
     visibility: visible;
 }

 .back-to-top:hover {
     background-color: var(--secondary);
     transform: translateY(-3px);
     box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
 }

 .back-to-top i {
     font-size: 1.25rem;
 }

 @media (max-width: 768px) {
     .back-to-top {
         width: 40px;
         height: 40px;
         bottom: 15px;
         right: 15px;
     }

     .back-to-top i {
         font-size: 1rem;
     }
 }