* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    background: #f4f4f4;
    line-height: 1.6;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

header {
    background: #333;
    color: white;
    padding: 20px 0;
    margin-bottom: 30px;
}

h1 {
    text-align: center;
}

.nav-tabs {
    display: flex;
    background: white;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 20px;
}

.nav-tab {
    flex: 1;
    padding: 15px;
    text-align: center;
    background: #e9e9e9;
    cursor: pointer;
    border: none;
    transition: background 0.3s;
    text-decoration: none;
    color: #333;
}

.nav-tab:hover {
    background: #d4d4d4;
}

.nav-tab.active {
    background: #007bff;
    color: white;
}

.sub-tabs {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 30px;
    justify-content: center;
}

.sub-tab {
    padding: 8px 16px;
    background: white;
    border: 2px solid #ddd;
    border-radius: 20px;
    cursor: pointer;
    transition: all 0.3s;
    text-decoration: none;
    color: #333;
}

.sub-tab:hover {
    border-color: #007bff;
}

.sub-tab.active {
    background: #007bff;
    color: white;
    border-color: #007bff;
}

.content-area {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

.serial-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.serial-table th,
.serial-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid #ddd;
}

.serial-table th {
    background: #f8f9fa;
    font-weight: bold;
    cursor: pointer;
    position: relative;
    padding-right: 25px !important;
}

.serial-table th:hover {
    background: #e9ecef;
}

.serial-table th::after {
    content: '';
    position: absolute;
    right: 8px;
    top: 50%;
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    opacity: 0.3;
}

.serial-table th::before {
    content: '';
    position: absolute;
    right: 8px;
    top: 50%;
    width: 0;
    height: 0;
    border-left: 5px solid transparent;
    border-right: 5px solid transparent;
    opacity: 0.3;
}

.serial-table th::before {
    border-bottom: 5px solid #666;
    margin-top: -8px;
}

.serial-table th::after {
    border-top: 5px solid #666;
    margin-top: 3px;
}

.serial-table th.sort-asc::before {
    opacity: 1;
}

.serial-table th.sort-desc::after {
    opacity: 1;
}

.serial-table th:hover::before,
.serial-table th:hover::after {
    opacity: 0.6;
}

.serial-table tr:hover {
    background: #f5f5f5;
}

.submit-form {
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
}

.btn {
    background: #007bff;
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    transition: background 0.3s;
}

.btn:hover {
    background: #0056b3;
}

.btn-danger {
    background: #dc3545;
}

.btn-danger:hover {
    background: #c82333;
}

.page-nav {
    text-align: center;
    margin-bottom: 20px;
}

.page-nav a {
    display: inline-block;
    padding: 10px 20px;
    margin: 0 5px;
    background: #007bff;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    transition: background 0.3s;
}

.page-nav a:hover {
    background: #0056b3;
}

.page-nav a.active {
    background: #0056b3;
}

.chart-container {
    margin-top: 30px;
    height: 400px;
    background: white;
    border-radius: 10px;
    padding: 20px;
}

.alert {
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
}

.alert-success {
    background: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-error {
    background: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.admin-table {
    font-size: 14px;
}

.admin-table td {
    max-width: 200px;
    word-wrap: break-word;
}

.photo-preview {
    max-width: 200px;
    max-height: 200px;
    border: 1px solid #ddd;
    border-radius: 5px;
}

.login-form {
    max-width: 400px;
    margin: 50px auto;
    background: white;
    padding: 30px;
    border-radius: 10px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.admin-header {
    background: #28a745;
    color: white;
    padding: 15px;
    border-radius: 5px;
    margin-bottom: 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
    overflow-y: auto;
}

.modal-content {
    background-color: white;
    margin: 40px auto;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: relative;
    max-width: 500px;
    width: 90%;
}

.modal-content h3 {
    margin-top: 0;
    margin-bottom: 20px;
    color: #333;
}

.modal-actions {
    margin-top: 20px;
    text-align: right;
}

.modal-actions button {
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    color: white;
    cursor: pointer;
}

.modal-actions button:hover {
    opacity: 0.9;
}

/* Form Styles */
.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: #333;
}

.form-group input[type="text"],
.form-group input[type="email"],
.form-group input[type="number"],
.form-group input[type="date"],
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

.form-group small {
    display: block;
    margin-top: 4px;
    color: #666;
    font-size: 12px;
}