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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f8f9fa;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.navbar-brand {
    font-weight: 700;
    font-size: 1.5rem;
}

.navbar-brand i {
    margin-right: 8px;
}

.navbar-dark .navbar-nav .nav-link {
    color: rgba(255, 255, 255, 0.85);
    transition: color 0.2s;
}

.navbar-dark .navbar-nav .nav-link:hover,
.navbar-dark .navbar-nav .nav-link.active {
    color: white;
}

.navbar-dark .navbar-nav .nav-link i {
    margin-right: 5px;
}

.card {
    border: none;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
    transition: box-shadow 0.3s;
    margin-bottom: 1.5rem;
}

.card:hover {
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

.card-header {
    font-weight: 600;
    border-bottom: 1px solid rgba(0, 0, 0, 0.125);
}

.btn {
    border-radius: 6px;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.3);
}

.btn-success {
    background: linear-gradient(135deg, #42e695 0%, #3bb2b8 100%);
    border: none;
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(66, 230, 149, 0.3);
}

.btn-outline-primary {
    border-width: 2px;
}

.btn-lg {
    padding: 0.75rem 2rem;
}

.form-control:focus {
    border-color: #667eea;
    box-shadow: 0 0 0 0.25rem rgba(102, 126, 234, 0.25);
}

.form-label {
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.input-group-text {
    background-color: #f8f9fa;
    border-color: #dee2e6;
}

.list-group-item {
    border: 1px solid rgba(0, 0, 0, 0.125);
    transition: background-color 0.2s;
}

.list-group-item:hover {
    background-color: #f8f9fa;
}

.list-group-item-action {
    color: #495057;
}

.list-group-item-action:hover {
    color: #212529;
}

.badge {
    font-weight: 500;
    padding: 0.35em 0.65em;
}

.alert {
    border: none;
    border-radius: 8px;
}

.alert-success {
    background: linear-gradient(135deg, #d4edda 0%, #c3e6cb 100%);
    color: #155724;
}

.alert-info {
    background: linear-gradient(135deg, #d1ecf1 0%, #bee5eb 100%);
    color: #0c5460;
}

.alert-warning {
    background: linear-gradient(135deg, #fff3cd 0%, #ffeaa7 100%);
    color: #856404;
}

.alert-danger {
    background: linear-gradient(135deg, #f8d7da 0%, #f5c6cb 100%);
    color: #721c24;
}

.footer {
    margin-top: auto;
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
}

.footer h5 {
    color: #495057;
    margin-bottom: 1rem;
}

.footer a {
    color: #6c757d;
    text-decoration: none;
    transition: color 0.2s;
}

.footer a:hover {
    color: #495057;
}

.jumbotron {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 12px;
}

.jumbotron h1 {
    font-weight: 700;
}

.jumbotron p.lead {
    font-size: 1.25rem;
    opacity: 0.9;
}

.stat-box {
    border: 2px solid transparent;
    background-clip: padding-box;
    position: relative;
    overflow: hidden;
}

.stat-box::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    border-radius: 4px;
    padding: 2px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: destination-out;
    mask-composite: exclude;
}

.stat-box h3 {
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.chat-messages {
    scrollbar-width: thin;
    scrollbar-color: #c1c1c1 #f1f1f1;
}

.chat-messages::-webkit-scrollbar {
    width: 8px;
}

.chat-messages::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

.chat-messages::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 4px;
}

.chat-messages::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8;
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    font-size: 1.2rem;
}

.user-avatar-sm {
    width: 30px;
    height: 30px;
    font-size: 1rem;
}

.message-bubble {
    position: relative;
    padding: 10px 15px;
    border-radius: 18px;
    max-width: 70%;
    word-wrap: break-word;
}

.message-bubble:after {
    content: '';
    position: absolute;
    bottom: 0;
    width: 20px;
    height: 20px;
}

.message-bubble.own {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    margin-left: auto;
}

.message-bubble.other {
    background: #f0f0f0;
    color: #333;
}

.upload-zone {
    border: 3px dashed #dee2e6;
    border-radius: 12px;
    padding: 3rem;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
    background: #f8f9fa;
}

.upload-zone:hover {
    border-color: #667eea;
    background: #f0f0f0;
}

.upload-zone.drag-over {
    border-color: #667eea;
    background: #e8f4f8;
}

.file-preview {
    border: 2px solid #e9ecef;
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 15px;
    background: white;
}

.file-icon {
    font-size: 3rem;
    color: #6c757d;
}

.file-info h6 {
    margin-bottom: 5px;
}

.progress {
    height: 10px;
    border-radius: 5px;
    background-color: #e9ecef;
}

.progress-bar {
    border-radius: 5px;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 100%);
}

.pagination .page-link {
    color: #667eea;
    border: 1px solid #dee2e6;
}

.pagination .page-item.active .page-link {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-color: #667eea;
}

.pagination .page-link:hover {
    background-color: #f8f9fa;
}

@media (max-width: 768px) {
    .jumbotron {
        padding: 2rem 1rem;
    }
    
    .jumbotron h1 {
        font-size: 2rem;
    }
    
    .stat-box {
        margin-bottom: 1rem;
    }
    
    .message-bubble {
        max-width: 85%;
    }
    
    .upload-zone {
        padding: 2rem 1rem;
    }
}

@media (max-width: 576px) {
    .navbar-brand {
        font-size: 1.2rem;
    }
    
    .btn-lg {
        padding: 0.5rem 1.5rem;
    }
    
    .card {
        margin-bottom: 1rem;
    }
}

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

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

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

.pulse {
    animation: pulse 2s infinite;
}

.text-gradient {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

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

.shadow-lg {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1) !important;
}

.shadow-xl {
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.15) !important;
}

.custom-scrollbar {
    scrollbar-width: thin;
    scrollbar-color: #c1c1c1 #f1f1f1;
}

.custom-scrollbar::-webkit-scrollbar {
    width: 6px;
}

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

.custom-scrollbar::-webkit-scrollbar-thumb {
    background: #c1c1c1;
    border-radius: 3px;
}

.custom-scrollbar::-webkit-scrollbar-thumb:hover {
    background: #a8a8a8;
}