:root {
    --primary-color: #667eea;
    --secondary-color: #764ba2;
    --success-color: #28a745;
    --danger-color: #dc3545;
    --warning-color: #ffc107;
    --info-color: #17a2b8;
    --light-color: #f8f9fa;
    --dark-color: #343a40;
    --border-radius: 10px;
    --box-shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f6fa;
}

.sidebar {
    background: linear-gradient(180deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    min-height: calc(100vh - 56px);
    box-shadow: var(--box-shadow);
}

.sidebar .nav-link {
    color: white;
    padding: 12px 20px;
    margin: 5px 15px;
    border-radius: var(--border-radius);
    transition: all 0.3s ease;
}

.sidebar .nav-link:hover,
.sidebar .nav-link.active {
    background-color: rgba(255, 255, 255, 0.2);
    color: white;
    transform: translateX(5px);
}

.sidebar .nav-link i {
    margin-right: 10px;
    width: 20px;
}

.card {
    border: none;
    border-radius: var(--border-radius);
    box-shadow: var(--box-shadow);
    margin-bottom: 20px;
    transition: transform 0.2s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

.card-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    border-radius: var(--border-radius) var(--border-radius) 0 0 !important;
    font-weight: 600;
}

.btn {
    border-radius: var(--border-radius);
    font-weight: 500;
    padding: 8px 20px;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border: none;
}

.btn-primary:hover {
    opacity: 0.9;
    transform: translateY(-1px);
}

.form-control,
.form-select {
    border-radius: var(--border-radius);
    border: 2px solid #e9ecef;
    padding: 10px 15px;
    transition: all 0.3s ease;
}

.form-control:focus,
.form-select:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25);
}

.table {
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--box-shadow);
    background: white;
}

.table th {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    border: none;
    font-weight: 600;
}

.table td {
    vertical-align: middle;
    border-color: #f8f9fa;
}

.badge {
    border-radius: 20px;
    padding: 5px 12px;
    font-weight: 500;
}

.alert {
    border-radius: var(--border-radius);
    border: none;
    margin-bottom: 20px;
}

/* Statistics Cards */
.stats-card {
    background: white;
    border-radius: var(--border-radius);
    padding: 30px;
    text-align: center;
    box-shadow: var(--box-shadow);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
}

.stats-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
}

.stats-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
}

.stats-card .stats-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 15px;
}

.stats-card .stats-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--dark-color);
    margin-bottom: 5px;
}

.stats-card .stats-label {
    color: #6c757d;
    font-weight: 500;
}

/* Chat Widget */
.chat-widget {
    position: fixed;
    bottom: 20px;
    right: 20px;
    width: 350px;
    background: white;
    border-radius: var(--border-radius);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.2);
    z-index: 1000;
    overflow: hidden;
}

.chat-header {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    padding: 15px 20px;
    cursor: pointer;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.chat-header i {
    margin-right: 10px;
}

.chat-body {
    height: 400px;
    display: flex;
    flex-direction: column;
}

.chat-messages {
    flex: 1;
    padding: 15px;
    overflow-y: auto;
    max-height: 300px;
}

.chat-message {
    margin-bottom: 15px;
    display: flex;
    align-items: flex-start;
}

.chat-message.user {
    justify-content: flex-end;
}

.chat-message .message-content {
    max-width: 80%;
    padding: 10px 15px;
    border-radius: 15px;
    word-wrap: break-word;
}

.chat-message.user .message-content {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    color: white;
    border-bottom-right-radius: 5px;
}

.chat-message.ai .message-content {
    background: #f8f9fa;
    color: var(--dark-color);
    border-bottom-left-radius: 5px;
}

.chat-input {
    padding: 15px;
    border-top: 1px solid #e9ecef;
    display: flex;
    gap: 10px;
}

.chat-input input {
    flex: 1;
    border: 1px solid #e9ecef;
    border-radius: 20px;
    padding: 8px 15px;
    outline: none;
}

.chat-input input:focus {
    border-color: var(--primary-color);
}

.chat-input button {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    border: none;
    color: white;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.chat-input button:hover {
    opacity: 0.9;
    transform: scale(1.05);
}

/* Article Editor */
.editor-toolbar {
    background: white;
    border: 1px solid #e9ecef;
    border-bottom: none;
    border-radius: var(--border-radius) var(--border-radius) 0 0;
    padding: 10px 15px;
}

.editor-content {
    min-height: 400px;
    border: 1px solid #e9ecef;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
    padding: 15px;
}

/* Responsive Design */
@media (max-width: 768px) {
    .chat-widget {
        width: 90%;
        right: 5%;
        left: 5%;
    }

    .stats-card {
        margin-bottom: 20px;
    }

    .table-responsive {
        border-radius: var(--border-radius);
    }
}

/* Loading Animation */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

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

/* Animations */
.fade-in {
    animation: fadeIn 0.5s ease-in;
}

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

.slide-in {
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from { transform: translateX(-100%); }
    to { transform: translateX(0); }
}

/* Custom Scrollbar */
.chat-messages::-webkit-scrollbar {
    width: 6px;
}

.chat-messages::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 3px;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: var(--primary-color);
    border-radius: 3px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: var(--secondary-color);
}