/* ===== App Layout ===== */
.app-container {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

/* ===== Header ===== */
.app-header {
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid var(--color-border-primary);
    transition: background-color var(--transition-normal), border-color var(--transition-normal);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--space-md) var(--space-xl);
    max-width: 1440px;
    margin: 0 auto;
    gap: var(--space-lg);
}

.header-brand {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    flex-shrink: 0;
}

.brand-icon {
    font-size: 2rem;
    line-height: 1;
}

.brand-title {
    font-size: var(--font-size-xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    letter-spacing: 0.02em;
    line-height: var(--line-height-tight);
}

.brand-subtitle {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    font-weight: var(--font-weight-normal);
    letter-spacing: 0.03em;
    margin-top: 2px;
}

.header-actions {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    flex: 1;
    justify-content: flex-end;
    max-width: 560px;
}

.search-wrapper {
    position: relative;
    display: flex;
    align-items: center;
    flex: 1;
    border-radius: var(--radius-xl);
    transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.search-wrapper:focus-within {
    border-color: var(--color-border-hover);
    box-shadow: 0 0 0 2px var(--color-accent-muted);
}

.search-icon {
    position: absolute;
    left: 14px;
    width: 18px;
    height: 18px;
    color: var(--color-text-tertiary);
    pointer-events: none;
    flex-shrink: 0;
}

.search-input {
    width: 100%;
    padding: 10px 40px 10px 42px;
    background: transparent;
    border: none;
    outline: none;
    font-size: var(--font-size-sm);
    color: var(--color-text-primary);
    border-radius: var(--radius-xl);
}

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

.search-clear {
    position: absolute;
    right: 8px;
    width: 24px;
    height: 24px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius-full);
    font-size: 18px;
    color: var(--color-text-tertiary);
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-fast), background-color var(--transition-fast);
}

.search-clear.visible {
    opacity: 1;
    pointer-events: auto;
}

.search-clear:hover {
    background-color: var(--color-bg-hover);
}

.theme-toggle {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: var(--radius-full);
    flex-shrink: 0;
    transition: background-color var(--transition-fast);
}

.theme-toggle:hover {
    background-color: var(--color-bg-hover);
}

.theme-icon {
    width: 20px;
    height: 20px;
    transition: opacity var(--transition-fast), transform var(--transition-fast);
}

[data-theme="light"] .theme-icon-light,
[data-theme="dark"] .theme-icon-dark {
    display: block;
}

[data-theme="light"] .theme-icon-dark,
[data-theme="dark"] .theme-icon-light {
    display: none;
}

/* ===== App Body ===== */
.app-body {
    display: flex;
    flex: 1;
    max-width: 1440px;
    margin: 0 auto;
    width: 100%;
    position: relative;
}

/* ===== Sidebar ===== */
.sidebar {
    width: 260px;
    flex-shrink: 0;
    padding: var(--space-lg) var(--space-md);
    border-right: 1px solid var(--color-border-primary);
    overflow-y: auto;
    height: calc(100vh - 73px);
    position: sticky;
    top: 73px;
    transition: transform var(--transition-normal), opacity var(--transition-normal);
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: var(--space-lg);
}

.nav-section {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.nav-heading {
    font-size: var(--font-size-xs);
    font-weight: var(--font-weight-semibold);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--color-text-tertiary);
    padding: 0 var(--space-sm);
    margin-bottom: var(--space-xs);
}

.nav-list {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.nav-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 8px var(--space-sm);
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    position: relative;
    user-select: none;
}

.nav-item:hover {
    background-color: var(--color-bg-hover);
    color: var(--color-text-primary);
}

.nav-item.active {
    background-color: var(--color-accent-muted);
    color: var(--color-text-primary);
    font-weight: var(--font-weight-medium);
}

.nav-item .nav-icon {
    font-size: 1.1em;
    width: 20px;
    text-align: center;
    flex-shrink: 0;
}

.nav-item .nav-count {
    margin-left: auto;
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    background: var(--color-bg-tertiary);
    padding: 2px 8px;
    border-radius: var(--radius-full);
}

.nav-sub-list {
    padding-left: var(--space-lg);
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.nav-sub-item {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 6px var(--space-sm);
    border-radius: var(--radius-md);
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    cursor: pointer;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.nav-sub-item:hover {
    background-color: var(--color-bg-hover);
    color: var(--color-text-secondary);
}

.nav-sub-item.active {
    background-color: var(--color-accent-muted);
    color: var(--color-text-primary);
    font-weight: var(--font-weight-medium);
}

.tag-cloud {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    padding: 0 var(--space-sm);
}

.tag-item {
    padding: 4px 10px;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    color: var(--color-tag-text);
    background: var(--color-tag-bg);
    cursor: pointer;
    transition: background-color var(--transition-fast), color var(--transition-fast);
    white-space: nowrap;
}

.tag-item:hover {
    background: var(--color-tag-hover);
    color: var(--color-text-primary);
}

.tag-item.active {
    background: var(--color-accent-primary);
    color: var(--color-text-inverse);
}

.sidebar-toggle {
    display: none;
    position: fixed;
    bottom: var(--space-lg);
    left: var(--space-lg);
    z-index: 90;
    width: 44px;
    height: 44px;
    border-radius: var(--radius-full);
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-md);
}

/* ===== Main Content ===== */
.main-content {
    flex: 1;
    min-width: 0;
    padding: var(--space-xl);
}

.content-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    margin-bottom: var(--space-lg);
    flex-wrap: wrap;
    gap: var(--space-md);
}

.content-title-area {
    display: flex;
    align-items: baseline;
    gap: var(--space-sm);
}

.content-title {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    letter-spacing: -0.01em;
}

.content-count {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    background: var(--color-bg-tertiary);
    padding: 2px 10px;
    border-radius: var(--radius-full);
}

.content-controls {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
}

.sort-select {
    padding: 8px 32px 8px 12px;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    background-color: var(--color-bg-glass);
    border: 1px solid var(--color-border-primary);
    outline: none;
    cursor: pointer;
    appearance: none;
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%238a8a8e' stroke-width='2'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 10px center;
    transition: border-color var(--transition-fast);
}

.sort-select:hover {
    border-color: var(--color-border-hover);
}

.sort-select:focus {
    border-color: var(--color-border-active);
}

.view-toggle {
    display: flex;
    border-radius: var(--radius-md);
    overflow: hidden;
    border: 1px solid var(--color-border-primary);
}

.view-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    color: var(--color-text-tertiary);
    background: transparent;
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

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

.view-btn.active {
    background-color: var(--color-accent-primary);
    color: var(--color-text-inverse);
}

/* ===== Breadcrumb ===== */
.breadcrumb {
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    margin-bottom: var(--space-md);
    font-size: var(--font-size-sm);
    flex-wrap: wrap;
}

.breadcrumb-item {
    color: var(--color-text-tertiary);
    cursor: pointer;
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    transition: color var(--transition-fast), background-color var(--transition-fast);
}

.breadcrumb-item:hover {
    color: var(--color-text-primary);
    background-color: var(--color-bg-hover);
}

.breadcrumb-item.active {
    color: var(--color-text-primary);
    font-weight: var(--font-weight-medium);
}

.breadcrumb-separator {
    color: var(--color-text-tertiary);
    font-size: 10px;
}

/* ===== Active Filters ===== */
.active-filters {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-md);
    min-height: 0;
}

.filter-chip {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    background: var(--color-accent-muted);
    color: var(--color-text-secondary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.filter-chip:hover {
    background: var(--color-bg-highlight);
    color: var(--color-text-primary);
}

.filter-chip-remove {
    font-size: 14px;
    line-height: 1;
    opacity: 0.6;
}

/* ===== Tools Grid ===== */
.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: var(--space-md);
}

.tools-grid.list-view {
    grid-template-columns: 1fr;
}

/* ===== Tool Card ===== */
.tool-card {
    position: relative;
    border-radius: var(--radius-lg);
    background: var(--color-bg-card);
    border: 1px solid var(--color-border-secondary);
    padding: var(--space-lg);
    cursor: pointer;
    transition: transform var(--transition-fast), box-shadow var(--transition-fast), border-color var(--transition-fast);
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
}

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

.tool-card-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: var(--space-sm);
}

.tool-card-icon {
    width: 44px;
    height: 44px;
    border-radius: var(--radius-md);
    background: var(--color-bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.4rem;
    flex-shrink: 0;
}

.tool-card-rating {
    display: flex;
    gap: 2px;
}

.star {
    font-size: 14px;
    color: var(--color-star);
    line-height: 1;
}

.star.empty {
    color: var(--color-star-empty);
}

.tool-card-body {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
}

.tool-card-name {
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-primary);
    line-height: var(--line-height-tight);
}

.tool-card-desc {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: var(--line-height-normal);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

.tool-card-footer {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-sm);
}

.tool-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 4px;
}

.tool-card-tag {
    padding: 2px 8px;
    border-radius: var(--radius-full);
    font-size: 11px;
    background: var(--color-tag-bg);
    color: var(--color-tag-text);
}

.tool-card-link {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 32px;
    height: 32px;
    border-radius: var(--radius-full);
    color: var(--color-text-tertiary);
    transition: background-color var(--transition-fast), color var(--transition-fast);
    flex-shrink: 0;
}

.tool-card-link:hover {
    background-color: var(--color-bg-hover);
    color: var(--color-text-primary);
}

/* List view card */
.tools-grid.list-view .tool-card {
    flex-direction: row;
    align-items: center;
    padding: var(--space-md) var(--space-lg);
    gap: var(--space-md);
}

.tools-grid.list-view .tool-card-body {
    flex: 1;
    flex-direction: row;
    align-items: center;
    gap: var(--space-md);
}

.tools-grid.list-view .tool-card-name {
    min-width: 160px;
    flex-shrink: 0;
}

.tools-grid.list-view .tool-card-desc {
    -webkit-line-clamp: 1;
}

.tools-grid.list-view .tool-card-footer {
    flex-shrink: 0;
}

/* ===== Featured Badge ===== */
.tool-card-badge {
    position: absolute;
    top: -1px;
    right: var(--space-lg);
    padding: 2px 12px;
    border-radius: 0 0 var(--radius-sm) var(--radius-sm);
    font-size: 10px;
    font-weight: var(--font-weight-semibold);
    letter-spacing: 0.05em;
    background: var(--color-accent-primary);
    color: var(--color-text-inverse);
}

/* ===== Empty State ===== */
.empty-state {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: var(--space-3xl) var(--space-xl);
    text-align: center;
    gap: var(--space-md);
}

.empty-icon {
    color: var(--color-text-tertiary);
    opacity: 0.4;
}

.empty-state h3 {
    font-size: var(--font-size-lg);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-secondary);
}

.empty-state p {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
}

.btn {
    padding: 10px 24px;
    border-radius: var(--radius-md);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

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

.btn-secondary:hover {
    background: var(--color-bg-highlight);
    color: var(--color-text-primary);
}

/* ===== Search Highlight ===== */
.search-highlight {
    background-color: var(--color-bg-highlight);
    border-radius: 2px;
    padding: 0 1px;
    font-weight: var(--font-weight-medium);
}

/* ===== Pagination ===== */
.pagination {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    margin-top: var(--space-xl);
    padding-top: var(--space-lg);
    border-top: 1px solid var(--color-border-secondary);
}

/* ===== Detail Overlay ===== */
.detail-overlay {
    position: fixed;
    inset: 0;
    z-index: 200;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity var(--transition-normal);
}

.detail-overlay.active {
    opacity: 1;
    pointer-events: auto;
}

.detail-backdrop {
    position: absolute;
    inset: 0;
    background: var(--color-bg-overlay);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
}

.detail-panel {
    position: relative;
    width: 90%;
    max-width: 720px;
    max-height: 85vh;
    border-radius: var(--radius-xl);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    box-shadow: var(--shadow-xl);
    transform: translateY(20px) scale(0.96);
    transition: transform var(--transition-normal);
}

.detail-overlay.active .detail-panel {
    transform: translateY(0) scale(1);
}

.detail-close {
    position: absolute;
    top: var(--space-md);
    right: var(--space-md);
    z-index: 10;
    width: 36px;
    height: 36px;
    border-radius: var(--radius-full);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 24px;
    color: var(--color-text-secondary);
    background: var(--color-bg-glass);
    backdrop-filter: blur(8px);
    transition: background-color var(--transition-fast), color var(--transition-fast);
}

.detail-close:hover {
    background: var(--color-bg-hover);
    color: var(--color-text-primary);
}

.detail-content {
    overflow-y: auto;
    padding: var(--space-xl);
}

.detail-header {
    display: flex;
    gap: var(--space-lg);
    margin-bottom: var(--space-lg);
    align-items: flex-start;
}

.detail-icon {
    width: 64px;
    height: 64px;
    border-radius: var(--radius-lg);
    background: var(--color-bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2rem;
    flex-shrink: 0;
}

.detail-info {
    flex: 1;
}

.detail-name {
    font-size: var(--font-size-2xl);
    font-weight: var(--font-weight-bold);
    color: var(--color-text-primary);
    margin-bottom: var(--space-xs);
}

.detail-category {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    margin-bottom: var(--space-sm);
}

.detail-rating {
    display: flex;
    gap: 2px;
    margin-bottom: var(--space-sm);
}

.detail-desc {
    font-size: var(--font-size-base);
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
    margin-bottom: var(--space-md);
}

.detail-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--space-sm);
    margin-bottom: var(--space-lg);
}

.detail-tag {
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: var(--font-size-xs);
    background: var(--color-tag-bg);
    color: var(--color-tag-text);
}

.detail-section {
    margin-bottom: var(--space-lg);
}

.detail-section h3 {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-semibold);
    color: var(--color-text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: var(--space-sm);
    padding-bottom: var(--space-sm);
    border-bottom: 1px solid var(--color-border-secondary);
}

.detail-usage {
    font-size: var(--font-size-sm);
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
}

.detail-link {
    display: inline-flex;
    align-items: center;
    gap: var(--space-sm);
    padding: 10px 20px;
    border-radius: var(--radius-md);
    background: var(--color-accent-primary);
    color: var(--color-text-inverse);
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    transition: opacity var(--transition-fast);
}

.detail-link:hover {
    opacity: 0.85;
}

.detail-related {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: var(--space-sm);
}

.detail-related-card {
    padding: var(--space-md);
    border-radius: var(--radius-md);
    background: var(--color-bg-tertiary);
    cursor: pointer;
    transition: background-color var(--transition-fast);
}

.detail-related-card:hover {
    background: var(--color-bg-highlight);
}

.detail-related-name {
    font-size: var(--font-size-sm);
    font-weight: var(--font-weight-medium);
    color: var(--color-text-primary);
    margin-bottom: 4px;
}

.detail-related-desc {
    font-size: var(--font-size-xs);
    color: var(--color-text-tertiary);
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
}

/* ===== Footer ===== */
.app-footer {
    border-top: 1px solid var(--color-border-primary);
    padding: var(--space-lg) var(--space-xl);
    text-align: center;
}

.footer-copyright {
    font-size: var(--font-size-sm);
    color: var(--color-text-tertiary);
    letter-spacing: 0.02em;
}

/* ===== Skeleton Loading ===== */
@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

.skeleton {
    background: linear-gradient(90deg, var(--color-bg-tertiary) 25%, var(--color-bg-secondary) 50%, var(--color-bg-tertiary) 75%);
    background-size: 200% 100%;
    animation: shimmer 1.5s infinite;
    border-radius: var(--radius-sm);
}

.skeleton-card {
    height: 180px;
    border-radius: var(--radius-lg);
}

/* ===== Animations ===== */
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.tool-card {
    animation: fadeIn var(--transition-normal) ease forwards;
}

.tool-card:nth-child(1) { animation-delay: 0s; }
.tool-card:nth-child(2) { animation-delay: 0.03s; }
.tool-card:nth-child(3) { animation-delay: 0.06s; }
.tool-card:nth-child(4) { animation-delay: 0.09s; }
.tool-card:nth-child(5) { animation-delay: 0.12s; }
.tool-card:nth-child(6) { animation-delay: 0.15s; }
.tool-card:nth-child(7) { animation-delay: 0.18s; }
.tool-card:nth-child(8) { animation-delay: 0.21s; }
.tool-card:nth-child(n+9) { animation-delay: 0.24s; }