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

:root {
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: rgba(99, 102, 241, 0.08);
    --success-color: #10b981;
    --success-light: rgba(16, 185, 129, 0.1);
    --warning-color: #f59e0b;
    --warning-light: rgba(245, 158, 11, 0.1);
    --danger-color: #ef4444;
    --danger-light: rgba(239, 68, 68, 0.1);
    --info-color: #3b82f6;
    --info-light: rgba(59, 130, 246, 0.1);
    --dark-color: #1e293b;
    --gray-color: #64748b;
    --light-gray: #f1f5f9;
    --border-color: #e2e8f0;
    --white: #ffffff;
    --sidebar-bg: #ffffff;
    --sidebar-text: #475569;
    --sidebar-hover: #f8fafc;
    --sidebar-active: #f1f5f9;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, 0.04);
    --card-shadow-hover: 0 4px 12px rgba(0, 0, 0, 0.08);
    --transition: all 0.2s ease;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #fafbfc;
    color: #334155;
    line-height: 1.5;
    font-size: 14px;
    -webkit-font-smoothing: antialiased;
}

.hidden {
    display: none !important;
}

.page {
    min-height: 100vh;
}

.login-background {
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea15 0%, #764ba215 100%), #ffffff;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.login-container {
    background: var(--white);
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.06);
    padding: 48px 40px;
    max-width: 420px;
    width: 100%;
    animation: slideUp 0.4s ease;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.login-header {
    text-align: center;
    margin-bottom: 36px;
}

.login-header .logo {
    width: 64px;
    height: 64px;
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 18px;
    font-size: 28px;
    color: var(--white);
}

.login-header h1 {
    font-size: 22px;
    color: var(--dark-color);
    margin-bottom: 8px;
    font-weight: 600;
}

.login-header p {
    color: var(--gray-color);
    font-size: 13px;
}

.login-form {
    margin-bottom: 28px;
}

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

.login-form .form-group i {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: #94a3b8;
    font-size: 16px;
}

.login-form .form-group input {
    width: 100%;
    padding: 12px 14px 12px 42px;
    border: 1.5px solid var(--border-color);
    border-radius: 10px;
    font-size: 14px;
    transition: var(--transition);
    outline: none;
    background: #fafbfc;
}

.login-form .form-group input:focus {
    border-color: var(--primary-color);
    background: var(--white);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.login-form .form-group input::placeholder {
    color: #94a3b8;
}

.login-footer {
    text-align: center;
    margin-bottom: 20px;
    padding-top: 15px;
    border-top: 1px solid var(--border-color);
}

.login-footer p {
    color: var(--gray-color);
    font-size: 14px;
}

.login-footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
}

.login-footer a:hover {
    text-decoration: underline;
}

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

.register-form .form-group {
    position: relative;
    margin-bottom: 16px;
}

.register-form .form-group i {
    position: absolute;
    left: 14px;
    top: 50%;
    transform: translateY(-50%);
    color: #94a3b8;
    font-size: 16px;
}

.register-form .form-group input,
.register-form .form-group select {
    width: 100%;
    padding: 12px 14px 12px 42px;
    border: 1.5px solid var(--border-color);
    border-radius: 10px;
    font-size: 14px;
    transition: var(--transition);
    outline: none;
    background: #fafbfc;
}

.register-form .form-group select {
    padding-left: 14px;
    cursor: pointer;
}

.register-form .form-group input:focus,
.register-form .form-group select:focus {
    border-color: var(--primary-color);
    background: var(--white);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    color: var(--white);
    box-shadow: 0 2px 8px rgba(99, 102, 241, 0.25);
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.35);
}

.btn-lg {
    padding: 13px 26px;
    font-size: 15px;
    width: 100%;
}

.btn-outline-light {
    background: transparent;
    color: var(--gray-color);
    border: 1.5px solid var(--border-color);
    padding: 7px 14px;
    font-size: 13px;
    white-space: nowrap;
    flex-shrink: 0;
    border-radius: 8px;
}

.sidebar.collapsed .btn-outline-light {
    padding: 10px;
}

.sidebar.collapsed .btn-outline-light span {
    display: none;
}

.btn-outline-light:hover {
    background: var(--light-gray);
    border-color: #cbd5e1;
}

.btn-success {
    background: var(--success-color);
    color: var(--white);
}

.btn-success:hover {
    background: #059669;
}

.btn-danger {
    background: var(--danger-color);
    color: var(--white);
}

.btn-danger:hover {
    background: #dc2626;
}

.btn-sm {
    padding: 6px 12px;
    font-size: 12px;
    border-radius: 6px;
}

.login-tips {
    background: var(--light-gray);
    border-radius: 12px;
    padding: 18px;
}

.tips-card h4 {
    color: var(--primary-color);
    font-size: 14px;
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 6px;
    font-weight: 600;
}

.tips-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.tip-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 14px;
    background: var(--white);
    border-radius: 8px;
}

.role-badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 12px;
    font-weight: 500;
}

.role-badge.admin {
    background: var(--danger-light);
    color: #dc2626;
}

.role-badge.teacher {
    background: var(--info-light);
    color: #2563eb;
}

.role-badge.student {
    background: var(--success-light);
    color: #059669;
}

.credentials {
    font-family: 'SF Mono', Monaco, monospace;
    font-size: 12px;
    color: var(--gray-color);
}

#main-page {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 240px;
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
    left: 0;
    top: 0;
    z-index: 100;
    transition: width 0.25s ease;
    border-right: 1px solid var(--border-color);
}

.sidebar.collapsed {
    width: 72px;
}

.sidebar-header {
    padding: 20px 18px;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.sidebar.collapsed .sidebar-header {
    padding: 20px 14px;
    flex-direction: column;
    gap: 12px;
}

.sidebar-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 16px;
    font-weight: 600;
    color: var(--dark-color);
}

.sidebar.collapsed .sidebar-logo {
    justify-content: center;
}

.sidebar.collapsed .sidebar-logo span {
    display: none;
}

.sidebar-logo i {
    font-size: 24px;
    color: var(--primary-color);
}

.sidebar-toggle {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--gray-color);
    width: 30px;
    height: 30px;
    border-radius: 6px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: var(--transition);
    font-size: 13px;
}

.sidebar-toggle:hover {
    background: var(--light-gray);
    border-color: #cbd5e1;
}

.sidebar.collapsed .sidebar-toggle i {
    transform: rotate(180deg);
}

.nav-menu {
    list-style: none;
    flex: 1;
    padding: 16px 12px;
    overflow-y: auto;
}

.nav-item {
    margin-bottom: 3px;
}

.nav-item a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 11px 12px;
    color: var(--sidebar-text);
    text-decoration: none;
    border-radius: 8px;
    transition: var(--transition);
    font-size: 13.5px;
    font-weight: 500;
}

.sidebar.collapsed .nav-item a {
    justify-content: center;
    padding: 11px 9px;
}

.sidebar.collapsed .nav-item a span {
    display: none;
}

.sidebar.collapsed .nav-item a {
    position: relative;
}

.sidebar.collapsed .nav-item a:hover::after {
    content: attr(data-tooltip);
    position: absolute;
    left: 100%;
    top: 50%;
    transform: translateY(-50%);
    background: var(--dark-color);
    color: var(--white);
    padding: 6px 10px;
    border-radius: 6px;
    font-size: 12px;
    white-space: nowrap;
    margin-left: 8px;
    z-index: 1000;
    font-weight: 500;
}

.nav-item a:hover,
.nav-item.active a {
    background: var(--sidebar-active);
    color: var(--primary-color);
}

.nav-item.active a {
    background: var(--primary-light);
    font-weight: 600;
}

.nav-item a i {
    font-size: 17px;
    width: 22px;
    text-align: center;
}

.nav-item.active a i {
    color: var(--primary-color);
}

.sidebar-footer {
    padding: 16px 18px;
    border-top: 1px solid var(--border-color);
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
}

.sidebar.collapsed .sidebar-footer {
    padding: 16px 12px;
    flex-direction: column;
    align-items: center;
}

.sidebar-footer .user-info {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 0;
}

.sidebar.collapsed .sidebar-footer .user-info {
    flex-direction: column;
    gap: 6px;
    margin-bottom: 10px;
}

.sidebar.collapsed .sidebar-footer .user-details {
    display: none;
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: var(--white);
}

.user-details .user-name {
    font-size: 13.5px;
    font-weight: 600;
    margin-bottom: 1px;
    color: var(--dark-color);
}

.user-details .user-role {
    font-size: 11.5px;
    color: var(--gray-color);
}

.main-content {
    flex: 1;
    margin-left: 240px;
    min-height: 100vh;
    transition: margin-left 0.25s ease;
    background: #fafbfc;
}

.main-content.collapsed {
    margin-left: 72px;
}

.top-bar {
    background: var(--white);
    padding: 18px 28px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 50;
}

.page-title {
    font-size: 19px;
    font-weight: 600;
    color: var(--dark-color);
}

.datetime {
    color: var(--gray-color);
    font-size: 13px;
}

.content-page {
    padding: 28px;
}

.welcome-section {
    margin-bottom: 28px;
}

.welcome-card {
    background: linear-gradient(135deg, #3b82f6 0%, #06b6d4 50%, #10b981 100%);
    border-radius: 14px;
    padding: 32px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    color: var(--white);
    position: relative;
    overflow: hidden;
}

.welcome-card::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(255,255,255,0.15) 0%, transparent 70%);
    border-radius: 50%;
}

.welcome-card::after {
    content: '';
    position: absolute;
    bottom: -30%;
    left: 20%;
    width: 200px;
    height: 200px;
    background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
    border-radius: 50%;
}

.welcome-text h2 {
    font-size: 23px;
    font-weight: 600;
    margin-bottom: 6px;
}

.welcome-text p {
    font-size: 14px;
    opacity: 0.92;
}

.welcome-icon {
    font-size: 56px;
    opacity: 0.25;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    margin-bottom: 28px;
}

.stat-card {
    background: var(--white);
    border-radius: 12px;
    padding: 22px;
    display: flex;
    gap: 16px;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
    transition: var(--transition);
}

.stat-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--card-shadow-hover);
    border-color: #cbd5e1;
}

.stat-card.primary .stat-icon {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.stat-card.success .stat-icon {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

.stat-card.warning .stat-icon {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.stat-card.info .stat-icon {
    background: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
}

.stat-icon {
    width: 52px;
    height: 52px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--white);
    flex-shrink: 0;
}

.stat-content {
    flex: 1;
}

.stat-content h3 {
    font-size: 13px;
    color: var(--gray-color);
    margin-bottom: 6px;
    font-weight: 500;
}

.stat-number {
    font-size: 28px;
    font-weight: 700;
    color: var(--dark-color);
    line-height: 1;
    margin-bottom: 4px;
}

.stat-label {
    font-size: 12px;
    color: var(--gray-color);
}

.content-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(380px, 1fr));
    gap: 20px;
}

.content-card {
    background: var(--white);
    border-radius: 12px;
    padding: 22px;
    box-shadow: var(--card-shadow);
    border: 1px solid var(--border-color);
}

.card-header {
    margin-bottom: 18px;
    padding-bottom: 14px;
    border-bottom: 1px solid var(--border-color);
}

.card-header h3 {
    font-size: 16px;
    font-weight: 600;
    color: var(--dark-color);
    display: flex;
    align-items: center;
    gap: 8px;
}

.quick-actions {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
}

.quick-btn {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 18px;
    background: var(--light-gray);
    border: 1px solid transparent;
    border-radius: 10px;
    cursor: pointer;
    transition: var(--transition);
    font-size: 13px;
    font-weight: 500;
    color: var(--dark-color);
}

.quick-btn:hover {
    background: var(--primary-light);
    color: var(--primary-color);
    border-color: rgba(99, 102, 241, 0.2);
    transform: translateY(-1px);
}

.quick-btn i {
    font-size: 22px;
}

.quick-btn span {
    font-size: 13px;
    font-weight: 500;
}

.tip-box {
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 12px;
    background: var(--light-gray);
    border-radius: 8px;
    margin-bottom: 8px;
}

.tip-box:last-child {
    margin-bottom: 0;
}

.tip-box i {
    font-size: 17px;
    margin-top: 1px;
}

.text-success {
    color: var(--success-color);
}

.text-info {
    color: var(--info-color);
}

.tip-box p {
    font-size: 13px;
    color: var(--gray-color);
    line-height: 1.5;
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 22px;
}

.page-header-left h2 {
    font-size: 19px;
    font-weight: 600;
    color: var(--dark-color);
    margin-bottom: 4px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.page-header-left p {
    color: var(--gray-color);
    font-size: 13px;
}

.card {
    background: var(--white);
    border-radius: 12px;
    box-shadow: var(--card-shadow);
    overflow: hidden;
    border: 1px solid var(--border-color);
}

.table-container {
    overflow-x: auto;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
}

.data-table thead {
    background: var(--light-gray);
}

.data-table th {
    padding: 13px 18px;
    text-align: left;
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-color);
    text-transform: uppercase;
    letter-spacing: 0.4px;
    white-space: nowrap;
}

.data-table td {
    padding: 14px 18px;
    border-bottom: 1px solid var(--border-color);
    font-size: 13.5px;
    color: #475569;
}

.data-table tbody tr {
    transition: var(--transition);
}

.data-table tbody tr:hover {
    background: #fafbfc;
}

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

.badge {
    display: inline-flex;
    align-items: center;
    padding: 3px 9px;
    border-radius: 5px;
    font-size: 11.5px;
    font-weight: 500;
}

.badge-success {
    background: var(--success-light);
    color: #059669;
}

.badge-warning {
    background: var(--warning-light);
    color: #d97706;
}

.badge-info {
    background: var(--info-light);
    color: #2563eb;
}

.badge-danger {
    background: var(--danger-light);
    color: #dc2626;
}

.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-backdrop {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.35);
    backdrop-filter: blur(3px);
}

.modal-dialog {
    position: relative;
    background: var(--white);
    border-radius: 14px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.12);
    width: 90%;
    max-width: 480px;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlide 0.25s ease;
}

@keyframes modalSlide {
    from {
        opacity: 0;
        transform: scale(0.97) translateY(-12px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 22px;
    border-bottom: 1px solid var(--border-color);
}

.modal-header h3 {
    font-size: 17px;
    font-weight: 600;
    color: var(--dark-color);
}

.modal-close {
    width: 32px;
    height: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    cursor: pointer;
    font-size: 16px;
    color: var(--gray-color);
    transition: var(--transition);
}

.modal-close:hover {
    background: var(--danger-light);
    border-color: var(--danger-color);
    color: var(--danger-color);
}

.modal-body {
    padding: 22px;
}

.modal-body .form-group {
    margin-bottom: 18px;
}

.modal-body .form-group label {
    display: block;
    margin-bottom: 6px;
    font-size: 13px;
    font-weight: 600;
    color: var(--dark-color);
}

.modal-body .form-group input,
.modal-body .form-group select,
.modal-body .form-group textarea {
    width: 100%;
    padding: 10px 14px;
    border: 1.5px solid var(--border-color);
    border-radius: 8px;
    font-size: 13.5px;
    transition: var(--transition);
    outline: none;
    background: #fafbfc;
}

.modal-body .form-group input:focus,
.modal-body .form-group select:focus,
.modal-body .form-group textarea:focus {
    border-color: var(--primary-color);
    background: var(--white);
    box-shadow: 0 0 0 3px var(--primary-light);
}

.modal-body .form-group .input-error {
    border-color: var(--danger-color) !important;
    background: #fef2f2 !important;
}

.modal-body .form-group .input-error:focus {
    box-shadow: 0 0 0 3px var(--danger-light) !important;
}

.form-error {
    color: var(--danger-color);
    font-size: 12px;
    margin-top: 5px;
    display: flex;
    align-items: center;
    gap: 4px;
    animation: shakeError 0.4s ease;
}

.form-error::before {
    content: '⚠';
    font-size: 13px;
}

@keyframes shakeError {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-3px); }
    75% { transform: translateX(3px); }
}

.modal-body .form-group textarea {
    resize: vertical;
    min-height: 90px;
}

.form-actions {
    display: flex;
    gap: 10px;
    justify-content: flex-end;
    margin-top: 20px;
    padding-top: 18px;
    border-top: 1px solid var(--border-color);
}

.form-actions .btn {
    min-width: 90px;
}

.form-actions .btn:first-child {
    background: var(--light-gray);
    color: var(--gray-color);
    border: 1.5px solid var(--border-color);
}

.form-actions .btn:first-child:hover {
    background: #e2e8f0;
    border-color: #cbd5e1;
}

@media (max-width: 1024px) {
    .sidebar {
        transform: translateX(-100%);
        transition: var(--transition);
    }
    .sidebar.open {
        transform: translateX(0);
    }
    .main-content {
        margin-left: 0;
    }
    .content-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .login-container {
        padding: 28px 22px;
    }
    .content-page {
        padding: 20px;
    }
    .stats-grid {
        grid-template-columns: 1fr;
    }
    .page-header {
        flex-direction: column;
        gap: 14px;
    }
    .page-header .btn {
        width: 100%;
    }
}

.toast-container {
    position: fixed;
    top: 18px;
    right: 18px;
    z-index: 9999;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.toast {
    background: var(--white);
    padding: 14px 18px;
    border-radius: 10px;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.1);
    display: flex;
    align-items: center;
    gap: 10px;
    min-width: 280px;
    animation: toastSlide 0.25s ease;
    border-left: 3px solid;
}

.toast-success {
    border-left-color: var(--success-color);
}

.toast-error {
    border-left-color: var(--danger-color);
}

.toast-warning {
    border-left-color: var(--warning-color);
}

.toast-info {
    border-left-color: var(--info-color);
}

.toast-icon {
    font-size: 18px;
}

.toast-success .toast-icon {
    color: var(--success-color);
}

.toast-error .toast-icon {
    color: var(--danger-color);
}

.toast-warning .toast-icon {
    color: var(--warning-color);
}

.toast-info .toast-icon {
    color: var(--info-color);
}

.toast-content {
    flex: 1;
}

.toast-content p {
    font-size: 13px;
    font-weight: 500;
    color: var(--dark-color);
}

.toast-close {
    background: none;
    border: none;
    color: var(--gray-color);
    cursor: pointer;
    font-size: 15px;
    padding: 3px;
    transition: var(--transition);
    border-radius: 4px;
}

.toast-close:hover {
    color: var(--dark-color);
    background: var(--light-gray);
}

@keyframes toastSlide {
    from {
        opacity: 0;
        transform: translateX(80px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.95);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9998;
}

.loading-spinner {
    text-align: center;
}

.loading-spinner i {
    font-size: 40px;
    color: var(--primary-color);
    animation: spin 1s linear infinite;
}

.loading-spinner p {
    margin-top: 14px;
    font-size: 14px;
    color: var(--gray-color);
    font-weight: 500;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

.empty-state {
    text-align: center;
    padding: 50px 20px;
    color: var(--gray-color);
}

.empty-state i {
    font-size: 56px;
    margin-bottom: 14px;
    opacity: 0.45;
}

.empty-state h3 {
    font-size: 16px;
    margin-bottom: 6px;
    color: var(--dark-color);
    font-weight: 600;
}

.empty-state p {
    font-size: 13px;
}

.btn:active {
    transform: scale(0.98);
}

.form-group input,
.form-group select,
.form-group textarea {
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.nav-item a {
    position: relative;
}

.nav-item.active a::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 3px;
    height: 20px;
    background: var(--primary-color);
    border-radius: 0 3px 3px 0;
}

.quick-btn {
    position: relative;
    overflow: hidden;
}

.quick-btn::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
    transition: left 0.4s ease;
}

.quick-btn:hover::before {
    left: 100%;
}

.modal-body .form-group label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
}

.modal-body .form-group input[type="checkbox"] {
    appearance: none;
    -webkit-appearance: none;
    width: 18px;
    height: 18px;
    padding: 0;
    border: 2px solid var(--border-color);
    border-radius: 5px;
    background: var(--white);
    cursor: pointer;
    position: relative;
    transition: var(--transition);
    flex-shrink: 0;
}

.modal-body .form-group input[type="checkbox"]:hover {
    border-color: var(--primary-color);
}

.modal-body .form-group input[type="checkbox"]:checked {
    background: linear-gradient(135deg, var(--primary-color), var(--info-color));
    border-color: var(--primary-color);
}

.modal-body .form-group input[type="checkbox"]:checked::after {
    content: '✓';
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    color: white;
    font-size: 12px;
    font-weight: bold;
}

.modal-body .form-group select {
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath fill='%2364748b' d='M6 8L1 3h10z'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 12px center;
    padding-right: 32px;
}

.modal-dialog::-webkit-scrollbar {
    width: 6px;
}

.modal-dialog::-webkit-scrollbar-track {
    background: transparent;
}

.modal-dialog::-webkit-scrollbar-thumb {
    background: #cbd5e1;
    border-radius: 3px;
}

.modal-dialog::-webkit-scrollbar-thumb:hover {
    background: #94a3b8;
}