:root {
    --bg-color: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --text-color: #ffffff;
    --text-secondary: #b0b0b0;
    --accent: #007acc;
    --accent-hover: #005a9e;
    --border: #404040;
    --hover: #2a2d2e;
    --success: #28a745;
    --warning: #ffc107;
    --danger: #dc3545;
    --info: #17a2b8;
}

[data-theme="light"] {
    --bg-color: #ffffff;
    --bg-secondary: #f5f5f5;
    --text-color: #333333;
    --text-secondary: #666666;
    --accent: #007acc;
    --accent-hover: #005a9e;
    --border: #dddddd;
    --hover: #e6e6e6;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
}

/* 布局 */
.navbar {
    background-color: var(--bg-secondary);
    height: 60px;
    border-bottom: 1px solid var(--border);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
    padding: 0 20px;
    max-width: 1400px;
    margin: 0 auto;
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 30px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--text-color);
    font-size: 1.2rem;
    font-weight: bold;
}

.logo i {
    color: var(--accent);
    font-size: 1.5rem;
}

.nav-search {
    display: flex;
    background-color: var(--bg-color);
    border-radius: 4px;
    overflow: hidden;
    width: 300px;
}

.nav-search input {
    flex: 1;
    border: none;
    background: none;
    padding: 8px 12px;
    color: var(--text-color);
    outline: none;
}

.nav-search button {
    background-color: var(--accent);
    border: none;
    color: white;
    padding: 0 15px;
    cursor: pointer;
}

.nav-right {
    display: flex;
    align-items: center;
    gap: 15px;
}

.current-time {
    color: var(--text-secondary);
    font-size: 0.9rem;
    padding: 8px 12px;
    background-color: rgba(0, 122, 204, 0.1);
    border-radius: 4px;
    border: 1px solid rgba(0, 122, 204, 0.3);
}

.nav-icon-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 50%;
    color: var(--text-color);
    text-decoration: none;
    transition: all 0.3s;
    position: relative;
}

.nav-icon-btn:hover {
    background-color: var(--hover);
    color: var(--accent);
}

.nav-icon-btn i {
    font-size: 1.2rem;
}

.nav-right .user-menu {
    position: relative;
    display: flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    padding: 5px 10px;
    border-radius: 4px;
}

.user-menu:hover {
    background-color: var(--hover);
}

.user-menu .avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
}

.user-menu .dropdown {
    display: none;
    position: absolute;
    top: 100%;
    right: 0;
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 4px;
    min-width: 200px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
    z-index: 1001;
}

.user-menu:hover .dropdown {
    display: block;
}

.dropdown a {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 10px 15px;
    color: var(--text-color);
    text-decoration: none;
    transition: background-color 0.2s;
}

.dropdown a:hover {
    background-color: var(--hover);
}

.dropdown .divider {
    height: 1px;
    background-color: var(--border);
    margin: 5px 0;
}

/* 侧边栏 */
.sidebar {
    position: fixed;
    left: 0;
    top: 60px;
    bottom: 0;
    width: 240px;
    background-color: var(--bg-secondary);
    border-right: 1px solid var(--border);
    padding: 0;
    padding-bottom: 120px;  /* 为底部版权信息预留空间 */
    overflow-y: auto;
}

/* 侧边栏头部 - 系统名称和图标 */
.sidebar-header {
    padding: 20px;
    border-bottom: 1px solid var(--border);
    background-color: rgba(0, 122, 204, 0.05);
}

.sidebar-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    text-decoration: none;
    color: var(--text-color);
    font-size: 1.1rem;
    font-weight: 600;
    transition: all 0.3s;
}

.sidebar-logo:hover {
    color: var(--accent);
}

.sidebar-logo img {
    width: 28px;
    height: 28px;
    border-radius: 4px;
}

.sidebar-logo span {
    flex: 1;
}

.storage-info {
    background-color: var(--bg-color);
    border-radius: 8px;
    padding: 15px;
    margin: 20px;
    margin-bottom: 20px;
}

.storage-progress {
    height: 6px;
    background-color: var(--border);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 8px;
}

.progress-bar {
    height: 100%;
    background-color: var(--accent);
    transition: width 0.3s;
}

.storage-text {
    display: flex;
    flex-direction: column;
    font-size: 0.9rem;
    color: var(--text-secondary);
    gap: 2px;
}

.storage-text > div:first-child {
    display: flex;
    justify-content: space-between;
}

.storage-label {
    font-size: 0.75rem;
    color: var(--text-secondary);
    opacity: 0.7;
    margin-top: 4px;
    text-align: center;
}

.nav-links {
    display: flex;
    flex-direction: column;
    gap: 5px;
    margin: 0 20px;
    margin-bottom: 30px;
}

.nav-link {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 15px;
    color: var(--text-color);
    text-decoration: none;
    border-radius: 6px;
    transition: all 0.2s;
}

.nav-link:hover,
.nav-link.active {
    background-color: var(--hover);
    color: var(--accent);
}

.nav-link i {
    width: 20px;
    text-align: center;
}

.quick-actions {
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin: 0 20px;
}

/* 底部版权信息 */
.footer-info {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    padding: 15px;
    border-top: 1px solid var(--border);
    background-color: rgba(0, 0, 0, 0.2);
}

.footer-info .version {
    color: var(--accent);
    font-weight: bold;
    font-size: 0.9rem;
    margin-bottom: 8px;
    text-align: center;
}

.footer-info button.version {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    width: auto;
    margin: 0 auto 8px;
    padding: 0.35rem 0.75rem;
    border: 1px solid rgba(0, 122, 204, 0.35);
    border-radius: 999px;
    background: rgba(0, 122, 204, 0.1);
    cursor: pointer;
    transition: all 0.2s ease;
}

.footer-info button.version:hover {
    background: rgba(0, 122, 204, 0.18);
    border-color: var(--accent);
}

.footer-info button.version.has-update {
    color: #ff6b6b;
    background: rgba(220, 53, 69, 0.15);
    border-color: rgba(220, 53, 69, 0.5);
}

.version-red-dot {
    display: none;
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #ff4d4d;
    box-shadow: 0 0 0 3px rgba(255, 77, 77, 0.18);
}

.has-update .version-red-dot {
    display: inline-block;
}

.version-modal-content {
    max-width: 420px;
}

.version-card {
    border: 1px solid rgba(40, 167, 69, 0.55);
    background: rgba(40, 167, 69, 0.1);
    border-radius: 12px;
    padding: 1rem;
}

.version-card.has-update {
    border-color: rgba(220, 53, 69, 0.6);
    background: rgba(220, 53, 69, 0.1);
}

.version-status-title {
    display: flex;
    align-items: center;
    gap: 0.6rem;
    margin-bottom: 0.8rem;
    color: #51cf66;
    font-weight: 700;
    font-size: 1.05rem;
}

.version-card.has-update .version-status-title {
    color: #ff6b6b;
}

.version-status-dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: #2ecc71;
}

.version-card.has-update .version-status-dot {
    background: #ff4d4d;
}

.version-info-list {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
}

.version-info-row {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.7rem 0.8rem;
    background: rgba(255, 255, 255, 0.75);
    color: #2f3b52;
    border-radius: 8px;
}

[data-theme="dark"] .version-info-row,
.version-info-row {
    background: rgba(255, 255, 255, 0.92);
}

.version-info-row.version-info-block {
    display: block;
}

.version-info-row strong {
    color: #2f3b52;
    white-space: nowrap;
}

.version-info-row span {
    text-align: right;
}

.version-text-box {
    margin-top: 0.6rem;
    padding: 0.8rem;
    border: 1px solid rgba(40, 167, 69, 0.45);
    border-radius: 8px;
    background: rgba(255, 255, 255, 0.65);
    color: #0b5132;
    white-space: pre-wrap;
    word-break: break-word;
    font-family: Consolas, Monaco, 'Courier New', monospace;
    font-size: 0.9rem;
}

.version-card.has-update .version-text-box {
    border-color: rgba(220, 53, 69, 0.45);
    color: #842029;
}

.version-result-success {
    color: #28a745;
    font-weight: 700;
}

.version-result-danger {
    color: #dc3545;
    font-weight: 700;
}

.footer-info .copyright {
    color: var(--text-secondary);
    font-size: 0.75rem;
    text-align: center;
    line-height: 1.4;
}

.footer-info .copyright .email {
    color: var(--text-secondary);
    opacity: 0.7;
    font-size: 0.7rem;
}

/* 主内容区域 */
.content {
    margin-left: 240px;
    margin-top: 60px;
    padding: 20px;
    min-height: calc(100vh - 60px);
}

/* 按钮 */
.btn {
    padding: 8px 16px;
    border: none;
    border-radius: 4px;
    font-size: 14px;
    cursor: pointer;
    transition: all 0.2s;
    font-weight: 500;
}

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

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

.btn-secondary {
    background-color: #6c757d;
    color: #fff;
    border: none;
}

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

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

.btn-danger:hover {
    background-color: #c82333;
}

.btn-block {
    width: 100%;
}

/* 统一按钮风格 */
.btn,
.btn-icon,
.btn-icon-small,
.view-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.35rem;
    text-decoration: none;
    line-height: 1;
}

.btn-icon,
.btn-icon-small {
    border: 1px solid var(--border);
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: all 0.2s ease;
}

.btn-icon {
    width: 40px;
    height: 40px;
    border-radius: 8px;
    padding: 0;
}

.btn-icon-small {
    width: 34px;
    height: 34px;
    border-radius: 6px;
    padding: 0;
    font-size: 0.85rem;
}

.btn-icon:hover,
.btn-icon-small:hover,
.view-btn:hover {
    background-color: var(--hover);
    color: var(--accent);
    border-color: var(--accent);
}

.btn-icon.btn-delete,
.btn-icon-small.btn-revoke {
    color: var(--danger);
}

.btn-icon.btn-delete:hover,
.btn-icon-small.btn-revoke:hover {
    background-color: rgba(220, 53, 69, 0.12);
    color: #ff6b6b;
    border-color: rgba(220, 53, 69, 0.45);
}

/* 统一卡片/列表容器风格 */
.stat-card,
.settings-card,
.feature,
.preview-container,
.trash-item,
.search-result-item,
.favorite-item,
.share-item,
.recent-item,
.file-item,
.editor-container,
.auth-form-wrapper {
    background-color: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 12px;
}

.stat-card,
.settings-card,
.feature,
.preview-container,
.editor-container,
.auth-form-wrapper {
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.16);
}

/* 统一标题与内容间距 */
h1, h2, h3, h4, h5, h6 {
    line-height: 1.25;
    letter-spacing: 0.2px;
}

.page-header,
.search-header,
.trash-header,
.auth-header,
.editor-header,
.landing-header,
.card-header,
.modal-header {
    gap: 0.75rem;
}

.page-header h2,
.search-header h2,
.trash-header h2,
.auth-header h1,
.editor-header h2,
.landing-title,
.stat-value,
.stat-label,
.preview-header h1 {
    text-wrap: balance;
    word-break: break-word;
}

.search-query,
.result-stats,
.pagination-info,
.item-path,
.file-date,
.file-size,
.link-url,
.preview-content p,
.feature p,
.auth-footer,
.storage-text,
.item-delete-time {
    line-height: 1.5;
}

/* 表格和文件列表 */
.file-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.file-table th,
.file-table td {
    padding: 12px;
    text-align: left;
    border-bottom: 1px solid var(--border);
}

.file-table th {
    background-color: var(--bg-secondary);
    color: var(--text-secondary);
    font-weight: 600;
    user-select: none;
}

.file-table th.sortable {
    cursor: pointer;
}

.file-table th.sortable:hover {
    background-color: var(--hover);
}

.file-table tr:hover {
    background-color: var(--hover);
}

.file-icon {
    width: 24px;
    height: 24px;
    margin-right: 8px;
    vertical-align: middle;
}

.file-row {
    cursor: pointer;
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0, 0, 0, 0.7);
    z-index: 2000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background-color: var(--bg-secondary);
    border-radius: 8px;
    width: 90%;
    max-width: 600px;
    max-height: 90vh;
    overflow: hidden;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.3);
}

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

.modal-body {
    padding: 20px;
    overflow-y: auto;
}

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

.close-modal {
    background: none;
    border: none;
    color: var(--text-secondary);
    font-size: 24px;
    cursor: pointer;
    padding: 0;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.close-modal:hover {
    color: var(--text-color);
}

/* 文件上传区域 */
.file-drop-area {
    border: 2px dashed var(--border);
    border-radius: 8px;
    padding: 40px;
    text-align: center;
    transition: all 0.3s;
    margin-bottom: 20px;
}

.file-drop-area.dragover {
    border-color: var(--accent);
    background-color: rgba(0, 122, 204, 0.1);
}

.file-drop-area i {
    font-size: 48px;
    color: var(--accent);
    margin-bottom: 15px;
}

.file-drop-area p {
    margin-bottom: 20px;
    color: var(--text-secondary);
}

#file-input {
    display: none;
}

.file-list {
    margin-top: 20px;
    text-align: left;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    background-color: var(--bg-color);
    border-radius: 4px;
    margin-bottom: 5px;
}

/* 面包屑导航 */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: 5px;
    margin-bottom: 20px;
    flex-wrap: wrap;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
}

.breadcrumb-item a {
    color: var(--text-color);
    text-decoration: none;
    padding: 4px 8px;
    border-radius: 4px;
}

.breadcrumb-item a:hover {
    background-color: var(--hover);
}

.breadcrumb-separator {
    color: var(--text-secondary);
}

/* 网格视图 */
.grid-view {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 15px;
    margin-top: 20px;
}

.grid-item {
    background-color: var(--bg-secondary);
    border-radius: 8px;
    padding: 15px;
    text-align: center;
    cursor: pointer;
    transition: all 0.2s;
    border: 1px solid transparent;
}

.grid-item:hover {
    background-color: var(--hover);
    border-color: var(--accent);
}

.grid-item.selected {
    border-color: var(--accent);
    background-color: rgba(0, 122, 204, 0.1);
}

.grid-icon {
    font-size: 36px;
    margin-bottom: 10px;
    color: var(--accent);
}

.grid-name {
    font-size: 14px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

/* 工具条 */
.toolbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border);
}

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

.view-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 6px 12px;
    border-radius: 4px;
    cursor: pointer;
}

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

/* 响应式设计 */
@media (max-width: 1024px) {
    .sidebar {
        width: 200px;
    }
    .content {
        margin-left: 200px;
    }
}

@media (max-width: 768px) {
    .navbar {
        height: auto;
        min-height: 60px;
    }

    .nav-container {
        flex-wrap: wrap;
        gap: 0.75rem;
        padding: 0.75rem 1rem;
    }

    .nav-left,
    .nav-right {
        width: 100%;
    }

    .nav-left {
        gap: 0.75rem;
    }

    .nav-search {
        width: 100%;
    }

    .nav-right {
        justify-content: space-between;
        flex-wrap: wrap;
    }

    .current-time {
        flex: 1 1 auto;
        text-align: center;
    }

    .user-menu {
        margin-left: auto;
    }

    .sidebar {
        top: 0;
        width: 100%;
        height: auto;
        max-height: 45vh;
        z-index: 999;
        border-right: none;
        border-bottom: 1px solid var(--border);
        padding-bottom: 20px;
        position: static;
        margin-top: 60px;
    }

    .sidebar-header {
        padding: 15px 20px;
    }

    .storage-info {
        margin: 15px 20px;
    }

    .nav-links,
    .quick-actions {
        margin: 0 15px 15px;
    }

    .footer-info {
        position: static;
        margin-top: 10px;
    }

    .content {
        margin-left: 0;
        margin-top: 20px;
        padding: 15px;
    }

    .toolbar {
        align-items: stretch;
        gap: 0.75rem;
    }

    .view-options {
        width: 100%;
        flex-wrap: wrap;
    }

    .file-count {
        width: 100%;
        margin-left: 0;
    }

    .breadcrumb {
        flex-wrap: wrap;
        gap: 0.35rem;
    }

    .modal-content {
        width: calc(100% - 1rem);
        max-width: none;
        margin: 0.5rem;
    }

    .version-info-row {
        align-items: flex-start;
    }

    .version-info-row:not(.version-info-block) {
        flex-direction: column;
        gap: 0.35rem;
    }

    .version-info-row span {
        text-align: left;
    }

    .file-table {
        display: block;
        overflow-x: auto;
        white-space: nowrap;
        -webkit-overflow-scrolling: touch;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 0.6rem 0.75rem;
    }

    .nav-search input {
        padding: 7px 10px;
        font-size: 0.95rem;
    }

    .current-time {
        font-size: 0.8rem;
        padding: 6px 10px;
    }

    .user-menu {
        gap: 8px;
        padding: 4px 8px;
        font-size: 0.9rem;
    }

    .user-menu .avatar {
        width: 28px;
        height: 28px;
    }

    .sidebar {
        max-height: 42vh;
    }

    .sidebar-logo {
        font-size: 1rem;
    }

    .storage-info,
    .nav-links,
    .quick-actions {
        margin-left: 12px;
        margin-right: 12px;
    }

    .nav-link {
        padding: 10px 12px;
    }

    .content {
        padding: 12px;
    }

    .toolbar {
        gap: 0.5rem;
    }

    .sort-options select,
    .page-size-selector select {
        width: 100%;
    }

    .page-size-selector {
        width: 100%;
        flex-wrap: wrap;
    }

    .file-item {
        padding: 0.85rem;
        gap: 0.75rem;
    }

    .modal-header,
    .modal-body,
    .modal-footer {
        padding-left: 0.9rem;
        padding-right: 0.9rem;
    }

    .version-card {
        padding: 0.8rem;
    }

    .version-text-box {
        font-size: 0.84rem;
    }

    .btn,
    .btn-icon,
    .btn-icon-small,
    .view-btn {
        min-height: 40px;
    }

    .btn-icon {
        width: 38px;
        height: 38px;
    }

    .btn-icon-small {
        width: 32px;
        height: 32px;
    }

    .stat-card,
    .settings-card,
    .feature,
    .preview-container,
    .trash-item,
    .search-result-item,
    .favorite-item,
    .share-item,
    .recent-item,
    .file-item,
    .editor-container,
    .auth-form-wrapper {
        border-radius: 10px;
    }

    .page-header,
    .search-header,
    .trash-header,
    .auth-header,
    .editor-header,
    .landing-header,
    .card-header,
    .modal-header {
        gap: 0.5rem;
    }
}

/* 登录/注册页面 */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-color) 100%);
}

.auth-box {
    background-color: var(--bg-secondary);
    border-radius: 12px;
    padding: 40px;
    width: 100%;
    max-width: 400px;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
}

.auth-header {
    text-align: center;
    margin-bottom: 30px;
}

.auth-header h1 {
    color: var(--accent);
    margin-bottom: 10px;
}

.auth-header p {
    color: var(--text-secondary);
}

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

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

.form-group .help-text {
    display: block;
    margin-top: 5px;
    font-size: 0.85rem;
    color: var(--text-secondary);
    font-style: italic;
}

.form-control {
    width: 100%;
    padding: 12px 15px;
    background-color: var(--bg-color);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-color);
    font-size: 14px;
    transition: border-color 0.2s;
}

.form-control:focus {
    outline: none;
    border-color: var(--accent);
}

.btn-auth {
    width: 100%;
    padding: 14px;
    font-size: 16px;
    margin-top: 10px;
}

.auth-footer {
    text-align: center;
    margin-top: 20px;
    color: var(--text-secondary);
}

.auth-footer a {
    color: var(--accent);
    text-decoration: none;
}

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

/* 文件夹树样式 */
.folder-tree {
    max-height: 500px;
    overflow-y: auto;
    background-color: var(--bg-color);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 10px;
}

.folder-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 10px;
    margin-bottom: 2px;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.2s;
    color: var(--text-color);
    position: relative;
}

.folder-item:hover {
    background-color: var(--hover);
}

/* 文件夹树选中状态（仅在复制/移动模态框中生效） */
#copy-move-modal #folder-tree .folder-item.selected {
    background-color: rgba(0, 122, 204, 0.3) !important;
    border: 2px solid var(--accent) !important;
    box-shadow: 0 0 0 3px rgba(0, 122, 204, 0.15) !important;
}

.folder-item.current {
    font-weight: bold;
}

.folder-item i {
    color: var(--accent);
    font-size: 16px;
}

/* 文件夹展开/折叠图标 */
.folder-toggle {
    width: 20px;
    height: 20px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: transform 0.2s;
    flex-shrink: 0;
}

.folder-toggle.empty {
    visibility: hidden;
}

.folder-toggle i {
    font-size: 12px;
    color: var(--text-secondary);
}

.folder-toggle.expanded i {
    transform: rotate(90deg);
}

.folder-toggle:hover i {
    color: var(--accent);
}

/* 文件夹占位符（保持对齐） */
.folder-toggle-placeholder {
    width: 20px;
    height: 20px;
    display: inline-block;
    flex-shrink: 0;
}

.folder-name {
    flex: 1;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.folder-tree .loading,
.folder-tree .error,
.folder-tree .empty {
    text-align: center;
    padding: 20px;
    color: var(--text-secondary);
}

.folder-tree .error {
    color: var(--danger);
}