* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

:root {
    --primary: #4361ee;
    --secondary: #3a0ca3;
    --accent: #4cc9f0;
    --light: #f8f9fa;
    --dark: #212529;
    --success: #4ade80;
    --warning: #f59e0b;
    --danger: #ef4444;
    --gray: #6c757d;
    --border-radius: 8px;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --transition: all 0.3s ease;
}

body {
    background-color: #f5f7fb;
    color: var(--dark);
    line-height: 1.6;
    min-height: 100vh;
}

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

/* Header Styles */
header {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: white;
    padding: 1.5rem 0;
    box-shadow: var(--shadow);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 1.5rem;
    font-weight: 700;
}

.logo i {
    font-size: 2rem;
}

.search-bar {
    display: flex;
    align-items: center;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50px;
    padding: 8px 15px;
    width: 300px;
}

.search-bar input {
    background: transparent;
    border: none;
    outline: none;
    color: white;
    width: 100%;
    padding: 5px;
}

.search-bar input::placeholder {
    color: rgba(255, 255, 255, 0.7);
}

.user-actions {
    display: flex;
    gap: 15px;
}

.btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    padding: 8px 15px;
    border-radius: var(--border-radius);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 5px;
    transition: var(--transition);
}

.btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

/* Main Content */
.main-content {
    display: flex;
    margin-top: 30px;
    gap: 30px;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background: white;
    border-radius: var(--border-radius);
    padding: 20px;
    box-shadow: var(--shadow);
    height: fit-content;
}

.sidebar-section {
    margin-bottom: 25px;
}

.sidebar-title {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 15px;
    color: var(--gray);
    text-transform: uppercase;
    letter-spacing: 1px;
}

.sidebar-menu {
    list-style: none;
}

.sidebar-menu li {
    margin-bottom: 10px;
}

.sidebar-menu a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px;
    border-radius: var(--border-radius);
    color: var(--dark);
    text-decoration: none;
    transition: var(--transition);
}

.sidebar-menu a:hover, .sidebar-menu a.active {
    background: rgba(67, 97, 238, 0.1);
    color: var(--primary);
}

.sidebar-menu a i {
    width: 20px;
    text-align: center;
}

.tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.tag {
    background: #e9ecef;
    padding: 5px 10px;
    border-radius: 20px;
    font-size: 0.8rem;
    cursor: pointer;
    transition: var(--transition);
}

.tag:hover {
    background: var(--accent);
    color: white;
}

/* Document Area */
.document-area {
    flex: 1;
}

.area-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.area-title {
    font-size: 1.5rem;
    font-weight: 600;
}

.view-options {
    display: flex;
    gap: 10px;
}

.view-btn {
    background: white;
    border: 1px solid #dee2e6;
    padding: 8px 12px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

.view-btn.active {
    background: var(--primary);
    color: white;
    border-color: var(--primary);
}

/* Document Grid */
.documents-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
}

.document-card {
    background: white;
    border-radius: var(--border-radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
    cursor: pointer;
}

.document-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
}

.document-thumbnail {
    height: 160px;
    background: linear-gradient(135deg, #a8c0ff, #3f2b96);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 3rem;
}

.document-info {
    padding: 15px;
}

.document-name {
    font-weight: 600;
    margin-bottom: 5px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.document-meta {
    display: flex;
    justify-content: space-between;
    color: var(--gray);
    font-size: 0.8rem;
}

.document-actions {
    display: flex;
    justify-content: space-between;
    margin-top: 10px;
    padding-top: 10px;
    border-top: 1px solid #e9ecef;
}

.action-btn {
    background: none;
    border: none;
    color: var(--gray);
    cursor: pointer;
    transition: var(--transition);
}

.action-btn:hover {
    color: var(--primary);
}

.action-btn.starred {
    color: var(--warning);
}

/* Empty State */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--gray);
}

.empty-state i {
    font-size: 4rem;
    margin-bottom: 20px;
    color: #dee2e6;
}

/* Upload Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
    align-items: center;
    justify-content: center;
}

.modal-content {
    background: white;
    border-radius: var(--border-radius);
    width: 500px;
    max-width: 90%;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.modal-header {
    padding: 20px;
    border-bottom: 1px solid #e9ecef;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-title {
    font-size: 1.25rem;
    font-weight: 600;
}

.close-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--gray);
}

.modal-body {
    padding: 20px;
}

.upload-area {
    border: 2px dashed #dee2e6;
    border-radius: var(--border-radius);
    padding: 40px 20px;
    text-align: center;
    margin-bottom: 20px;
    cursor: pointer;
    transition: var(--transition);
}

.upload-area:hover {
    border-color: var(--primary);
}

.upload-area i {
    font-size: 3rem;
    color: var(--gray);
    margin-bottom: 15px;
}

.form-group {
    margin-bottom: 15px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 10px;
    border: 1px solid #dee2e6;
    border-radius: var(--border-radius);
    font-size: 1rem;
}

.modal-footer {
    padding: 20px;
    border-top: 1px solid #e9ecef;
    display: flex;
    justify-content: flex-end;
    gap: 10px;
}

.btn-primary {
    background: var(--primary);
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

.btn-primary:hover {
    background: var(--secondary);
}

.btn-secondary {
    background: #6c757d;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

.btn-secondary:hover {
    background: #5a6268;
}

/* Toast Notification */
.toast {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background: var(--success);
    color: white;
    padding: 15px 25px;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow);
    display: flex;
    align-items: center;
    gap: 10px;
    transform: translateY(100px);
    opacity: 0;
    transition: var(--transition);
    z-index: 1100;
}

.toast.show {
    transform: translateY(0);
    opacity: 1;
}

/* Folder Structure */
.folder-structure {
    margin-bottom: 20px;
}

.folder-path {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: wrap;
}

.folder-path-item {
    display: flex;
    align-items: center;
    gap: 5px;
    color: var(--gray);
    cursor: pointer;
}

.folder-path-item:last-child {
    color: var(--primary);
    font-weight: 600;
}

.folder-path-item:not(:last-child):hover {
    color: var(--dark);
}

/* Responsive Design */
@media (max-width: 992px) {
    .main-content {
        flex-direction: column;
    }
    
    .sidebar {
        width: 100%;
    }
    
    .documents-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        gap: 15px;
    }
    
    .search-bar {
        width: 100%;
    }
    
    .documents-grid {
        grid-template-columns: 1fr;
    }
}