:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-card: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #2563eb;
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --transition-fast: 150ms ease-in-out;
    --transition-normal: 200ms ease-in-out;
}

.dark {
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-card: #1e293b;
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --accent-color: #60a5fa;
    --accent-hover: #3b82f6;
    --border-color: #334155;
}

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

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    transition: background-color var(--transition-normal), color var(--transition-normal);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem;
    padding-bottom: 6rem;
}

.header {
    margin-bottom: 1.5rem;
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.title {
    font-size: 1.75rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--accent-color), #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.theme-toggle {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 0.5rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    color: var(--text-secondary);
}

.theme-toggle:hover {
    background: var(--bg-secondary);
    transform: rotate(10deg);
}

.theme-toggle .icon {
    width: 1.25rem;
    height: 1.25rem;
    transition: opacity var(--transition-fast);
}

.theme-toggle .moon {
    display: none;
}

.dark .theme-toggle .sun {
    display: none;
}

.dark .theme-toggle .moon {
    display: block;
}

.search-container {
    position: relative;
    display: flex;
    gap: 0.5rem;
}

.search-input {
    flex: 1;
    padding: 0.75rem 1rem;
    padding-right: 3rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 1rem;
    color: var(--text-primary);
    transition: all var(--transition-fast);
    outline: none;
}

.search-input:focus {
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

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

.search-btn {
    position: absolute;
    right: 0.5rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    padding: 0.5rem;
    cursor: pointer;
    color: var(--text-muted);
    transition: color var(--transition-fast);
}

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

.search-btn svg {
    width: 1.25rem;
    height: 1.25rem;
}

.category-tabs {
    display: flex;
    gap: 0.5rem;
    overflow-x: auto;
    padding-bottom: 0.5rem;
    margin-bottom: 1.5rem;
    scrollbar-width: none;
}

.category-tabs::-webkit-scrollbar {
    display: none;
}

.tab {
    flex-shrink: 0;
    padding: 0.5rem 1rem;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.tab:hover {
    background: var(--bg-secondary);
}

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

.main-content {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.category-section {
    animation: fadeIn 200ms ease-in-out;
}

.category-section.hidden {
    display: none;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.category-title {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 1rem;
}

.category-title svg {
    width: 1.25rem;
    height: 1.25rem;
    color: var(--accent-color);
}

.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    gap: 1rem;
}

.site-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 1rem;
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.site-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    border-color: var(--accent-color);
}

.site-card:active {
    transform: scale(0.98);
}

.site-header {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.site-favicon {
    flex-shrink: 0;
    width: 2.5rem;
    height: 2.5rem;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 700;
    color: white;
    background: linear-gradient(135deg, var(--accent-color), #8b5cf6);
}

.site-name {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-primary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.site-description {
    font-size: 0.75rem;
    color: var(--text-muted);
    line-height: 1.4;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.site-card:hover .delete-btn {
    opacity: 1;
}

.delete-btn {
    position: absolute;
    top: 0.25rem;
    right: 0.25rem;
    background: rgba(239, 68, 68, 0.9);
    border: none;
    border-radius: 50%;
    width: 1.5rem;
    height: 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    transition: opacity var(--transition-fast);
}

.delete-btn:hover {
    background: #ef4444;
}

.delete-btn svg {
    width: 0.75rem;
    height: 0.75rem;
    color: white;
}

.add-modal {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all var(--transition-normal);
}

.add-modal.show {
    opacity: 1;
    visibility: visible;
}

.modal-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: 1.5rem;
    width: 90%;
    max-width: 400px;
    box-shadow: var(--shadow-lg);
    transform: scale(0.95);
    transition: transform var(--transition-normal);
}

.add-modal.show .modal-content {
    transform: scale(1);
}

.modal-content h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
}

.form-group input,
.form-group select {
    width: 100%;
    padding: 0.75rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    color: var(--text-primary);
    outline: none;
    transition: border-color var(--transition-fast);
}

.form-group input:focus,
.form-group select:focus {
    border-color: var(--accent-color);
}

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

.input-group {
    display: flex;
    gap: 0.5rem;
}

.input-group input {
    flex: 1;
}

.btn-add {
    padding: 0.75rem 1rem;
    background: var(--accent-color);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: background var(--transition-fast);
}

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

.category-list {
    max-height: 200px;
    overflow-y: auto;
    margin-top: 1rem;
    padding-right: 0.5rem;
}

.category-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0.75rem;
    background: var(--bg-primary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    margin-bottom: 0.5rem;
}

.category-item .category-icon {
    font-size: 1.25rem;
    margin-right: 0.75rem;
}

.category-item .category-name {
    flex: 1;
    font-weight: 500;
    color: var(--text-primary);
}

.category-actions {
    display: flex;
    gap: 0.5rem;
}

.rename-btn,
.delete-cat-btn {
    padding: 0.375rem 0.75rem;
    border: none;
    border-radius: var(--radius-sm);
    font-size: 0.75rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.rename-btn {
    background: var(--bg-secondary);
    color: var(--text-secondary);
}

.rename-btn:hover {
    background: var(--border-color);
}

.delete-cat-btn {
    background: rgba(239, 68, 68, 0.1);
    color: #ef4444;
}

.delete-cat-btn:hover {
    background: rgba(239, 68, 68, 0.2);
}

.modal-actions {
    display: flex;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.btn-cancel,
.btn-confirm {
    flex: 1;
    padding: 0.75rem;
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
    border: none;
}

.btn-cancel {
    background: var(--bg-secondary);
    color: var(--text-secondary);
}

.btn-cancel:hover {
    background: var(--border-color);
}

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

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

.footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-card);
    border-top: 1px solid var(--border-color);
    padding: 0.75rem 1rem;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 1rem;
}

.add-btn {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    background: var(--accent-color);
    border: none;
    border-radius: 50%;
    width: 3rem;
    height: 3rem;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-fast);
}

.add-btn:hover {
    background: var(--accent-hover);
    transform: translateY(-50%) scale(1.1);
}

.add-btn:active {
    transform: translateY(-50%) scale(0.95);
}

.add-btn svg {
    width: 1.5rem;
    height: 1.5rem;
    color: white;
}

.footer p {
    font-size: 0.75rem;
    color: var(--text-muted);
}

.login-container {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    padding: 1rem;
}

.login-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-xl);
    padding: 2rem;
    width: 100%;
    max-width: 400px;
    box-shadow: var(--shadow-lg);
}

.login-title {
    font-size: 1.5rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.login-hint {
    text-align: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-top: 1rem;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.view-site-btn {
    padding: 0.5rem 1rem;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.view-site-btn:hover {
    background: var(--border-color);
}

.hidden {
    display: none !important;
}

@media (min-width: 768px) {
    .container {
        padding: 2rem;
        padding-bottom: 5rem;
    }

    .header {
        margin-bottom: 2rem;
    }

    .title {
        font-size: 2.25rem;
    }

    .category-tabs {
        margin-bottom: 2rem;
    }

    .tab {
        padding: 0.625rem 1.25rem;
        font-size: 1rem;
    }

    .card-grid {
        grid-template-columns: repeat(auto-fill, minmax(160px, 1fr));
        gap: 1.25rem;
    }

    .site-card {
        padding: 1.25rem;
    }

    .site-favicon {
        width: 3.5rem;
        height: 3.5rem;
        font-size: 1.75rem;
    }

    .site-name {
        font-size: 1rem;
    }
}

@media (min-width: 1024px) {
    .card-grid {
        grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
    }
}