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

:root {
    --primary: #4f46e5;
    --primary-dark: #4338ca;
    --primary-light: #818cf8;
    --accent: #06b6d4;
    --bg: #f8fafc;
    --bg-alt: #f1f5f9;
    --surface: #ffffff;
    --surface-hover: #f8fafc;
    --border: #e2e8f0;
    --border-dark: #cbd5e1;
    --text: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --success: #10b981;
    --success-light: #d1fae5;
    --danger: #ef4444;
    --danger-light: #fee2e2;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: linear-gradient(135deg, #e0e7ff 0%, #f3e8ff 50%, #e0f2fe 100%);
}

.login-box {
    background: var(--surface);
    padding: 48px 40px;
    border-radius: 20px;
    box-shadow: 
        0 20px 25px -5px rgba(0, 0, 0, 0.1),
        0 8px 10px -6px rgba(0, 0, 0, 0.1);
    width: 400px;
    border: 1px solid var(--border);
}

.login-box h1 {
    text-align: center;
    margin-bottom: 6px;
    font-size: 24px;
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.5px;
}

.login-box .subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 36px;
}

.form-group {
    margin-bottom: 24px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 14px;
    font-weight: 500;
    color: var(--text);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1.5px solid var(--border);
    border-radius: 10px;
    font-size: 14px;
    background: var(--surface);
    color: var(--text);
    transition: all 0.2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

.form-group input::placeholder {
    color: var(--text-muted);
}

.btn-primary {
    width: 100%;
    padding: 14px;
    background: linear-gradient(135deg, var(--primary) 0%, #6366f1 100%);
    color: #fff;
    border: none;
    border-radius: 10px;
    font-size: 15px;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s;
    letter-spacing: 0.3px;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 10px 20px -5px rgba(79, 70, 229, 0.4);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-secondary {
    padding: 12px 24px;
    background: var(--surface);
    color: var(--text-secondary);
    border: 1.5px solid var(--border);
    border-radius: 8px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-secondary:hover {
    background: var(--bg);
    border-color: var(--border-dark);
    color: var(--text);
}

.btn-sm {
    padding: 6px 12px;
    background: var(--bg);
    color: var(--text-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    cursor: pointer;
    font-size: 12px;
    font-weight: 500;
    transition: all 0.2s;
    margin-right: 6px;
}

.btn-sm:hover {
    background: var(--primary);
    color: #fff;
    border-color: var(--primary);
}

.btn-danger {
    background: var(--danger-light);
    border-color: transparent;
    color: var(--danger);
}

.btn-danger:hover {
    background: var(--danger);
    color: #fff;
    border-color: var(--danger);
}

.error-msg {
    color: var(--danger);
    text-align: center;
    margin-top: 16px;
    font-size: 13px;
    font-weight: 500;
}

.main-container {
    display: flex;
    min-height: 100vh;
}

.sidebar {
    width: 260px;
    background: var(--surface);
    color: var(--text);
    position: fixed;
    height: 100vh;
    overflow-y: auto;
    border-right: 1px solid var(--border);
    box-shadow: 4px 0 6px -1px rgba(0, 0, 0, 0.05);
}

.sidebar-header {
    padding: 28px 24px;
    border-bottom: 1px solid var(--border);
    background: linear-gradient(180deg, var(--surface) 0%, var(--bg) 100%);
}

.sidebar-header h2 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 4px;
    color: var(--text);
    letter-spacing: -0.3px;
}

.user-name {
    font-size: 13px;
    color: var(--text-secondary);
    font-weight: 500;
}

.nav-menu {
    padding: 16px 12px;
}

.nav-menu a {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all 0.2s;
    border-radius: 10px;
    margin-bottom: 4px;
    font-size: 14px;
    font-weight: 500;
}

.nav-menu a:hover {
    background: var(--bg);
    color: var(--text);
}

.nav-menu a.active {
    background: linear-gradient(135deg, rgba(79, 70, 229, 0.1) 0%, rgba(79, 70, 229, 0.05) 100%);
    color: var(--primary);
}

.nav-menu a .icon {
    margin-right: 12px;
    font-size: 18px;
    width: 24px;
    text-align: center;
}

.nav-menu a.logout {
    margin-top: 40px;
    border-top: 1px solid var(--border);
    padding-top: 20px;
    margin-top: auto;
    color: var(--text-muted);
}

.nav-menu a.logout:hover {
    color: var(--danger);
    background: var(--danger-light);
}

.content {
    flex: 1;
    margin-left: 260px;
    padding: 32px 40px;
    background: var(--bg);
}

.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 28px;
}

.page-header h2 {
    font-size: 24px;
    font-weight: 700;
    color: var(--text);
    letter-spacing: -0.3px;
}

.page-header .btn-primary {
    width: auto;
    padding: 12px 24px;
}

.filter-bar {
    margin-bottom: 24px;
}

.filter-bar select {
    padding: 10px 16px;
    border: 1.5px solid var(--border);
    border-radius: 8px;
    font-size: 14px;
    background: var(--surface);
    color: var(--text);
    min-width: 180px;
    cursor: pointer;
    font-weight: 500;
}

.filter-bar select:hover {
    border-color: var(--border-dark);
}

.category-tree {
    background: var(--surface);
    border-radius: 16px;
    padding: 24px;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    border: 1px solid var(--border);
}

.category-item {
    margin-bottom: 16px;
}

.category-item:last-child {
    margin-bottom: 0;
}

.category-row {
    display: flex;
    align-items: center;
    padding: 14px 18px;
    border-radius: 12px;
    margin-bottom: 8px;
    transition: all 0.2s;
    border: 1.5px solid transparent;
    background: var(--bg);
}

.category-row.parent {
    background: linear-gradient(135deg, var(--primary) 0%, #818cf8 100%);
    color: #fff;
    border: none;
}

.category-row.parent .cat-name {
    color: #fff;
}

.category-row.parent .cat-icon {
    filter: brightness(0) invert(1);
}

.category-row.parent .btn-sm {
    background: rgba(255, 255, 255, 0.2);
    color: #fff;
    border: none;
}

.category-row.parent .btn-sm:hover {
    background: rgba(255, 255, 255, 0.3);
}

.category-row.parent .btn-danger {
    background: rgba(255, 255, 255, 0.2);
    color: #fff;
}

.category-row.parent .btn-danger:hover {
    background: #fff;
    color: var(--danger);
}

.category-row.child {
    background: var(--surface);
    border: 1.5px solid var(--border);
    margin-left: 32px;
}

.category-row.child:hover {
    border-color: var(--primary-light);
    box-shadow: 0 4px 12px -2px rgba(79, 70, 229, 0.15);
}

.cat-icon {
    margin-right: 14px;
    font-size: 20px;
    width: 28px;
    text-align: center;
}

.cat-name {
    flex: 1;
    font-weight: 600;
    font-size: 14px;
    color: var(--text);
}

.category-row.child .cat-name {
    font-weight: 500;
}

.cat-actions {
    display: flex;
    gap: 4px;
}

.data-table {
    width: 100%;
    background: var(--surface);
    border-radius: 16px;
    box-shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1);
    border-collapse: separate;
    border-spacing: 0;
    overflow: hidden;
    border: 1px solid var(--border);
}

.data-table th,
.data-table td {
    padding: 16px 20px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.data-table th {
    background: var(--bg);
    font-weight: 600;
    font-size: 12px;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

.data-table tr:hover td {
    background: var(--surface-hover);
}

.data-table td:first-child {
    font-weight: 600;
    color: var(--primary);
}

.desc-cell {
    max-width: 200px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    color: var(--text-secondary);
    font-size: 13px;
}

.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    backdrop-filter: blur(2px);
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 1000;
    animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

.modal {
    background: var(--surface);
    border-radius: 20px;
    padding: 32px;
    width: 480px;
    max-height: 85vh;
    overflow-y: auto;
    border: 1px solid var(--border);
    box-shadow: 
        0 25px 50px -12px rgba(0, 0, 0, 0.25);
    animation: slideUp 0.3s ease-out;
}

@keyframes slideUp {
    from { 
        opacity: 0;
        transform: translateY(20px) scale(0.95);
    }
    to { 
        opacity: 1;
        transform: translateY(0) scale(1);
    }
}

.modal-lg {
    width: 600px;
}

.modal h3 {
    margin-bottom: 24px;
    font-size: 18px;
    font-weight: 700;
    color: var(--text);
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}

.form-row {
    display: flex;
    gap: 16px;
}

.form-row .form-group {
    flex: 1;
}

.form-actions {
    display: flex;
    justify-content: flex-end;
    gap: 12px;
    margin-top: 24px;
    padding-top: 20px;
    border-top: 1px solid var(--border);
}

.form-group input[type="checkbox"] {
    width: auto;
    margin-right: 8px;
    accent-color: var(--primary);
}

.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-muted);
}

.empty-state .icon {
    font-size: 48px;
    margin-bottom: 16px;
    opacity: 0.5;
}

::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--border-dark);
    border-radius: 3px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-muted);
}