/* ============================================
   CSS Variables & Reset
   ============================================ */

/* Prevent text cursor on non-input elements */
*:not(input):not(textarea):not([contenteditable="true"]) {
    caret-color: transparent;
}

/* Prevent text selection on UI elements */
.card-item,
.search-card,
.group-card,
.schema-card,
.part-item,
.part-variant-item,
.brand-card,
.model-card,
.back-btn,
.btn,
.breadcrumb-item,
.modal-close,
.modal-header,
.header,
.part-expand-icon,
.part-chevron,
.parts-section-divider {
    user-select: none;
    -webkit-user-select: none;
    cursor: pointer;
}

:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary: #64748b;
    --success: #10b981;
    --warning: #f59e0b;
    --error: #ef4444;
    
    --bg-primary: #f8fafc;
    --bg-secondary: #ffffff;
    --bg-tertiary: #f1f5f9;
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-tertiary: #94a3b8;
    
    --border-color: #e2e8f0;
    --shadow-sm: 0 1px 2px 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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-full: 9999px;
    
    --transition: all 0.2s ease;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

/* ============================================
   Header
   ============================================ */
.header {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    padding: 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow-md);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.header-icon {
    font-size: 2rem;
}

.header h1 {
    font-size: 1.25rem;
    font-weight: 600;
}

/* ============================================
   Main Content
   ============================================ */
.main {
    flex: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.5rem;
    width: 100%;
}

/* ============================================
   Sections
   ============================================ */
.section {
    display: none;
    animation: fadeIn 0.3s ease;
}

.section.active {
    display: block;
}

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

.section-title {
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.25rem;
    color: var(--text-primary);
}

.section-subtitle {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

/* ============================================
   Back Button
   ============================================ */
.back-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: none;
    border: none;
    color: var(--primary);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    padding: 0.5rem 0;
    margin-bottom: 1rem;
    transition: var(--transition);
}

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

.back-btn .material-icons {
    font-size: 1.25rem;
}

/* ============================================
   Search Method Cards
   ============================================ */
.search-options {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 1rem;
}

.search-card {
    background: var(--bg-secondary);
    border-radius: var(--radius-lg);
    padding: 2rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: 2px solid transparent;
    box-shadow: var(--shadow-sm);
}

.search-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-light);
}

.search-card .material-icons {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

.search-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.search-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

/* ============================================
   VIN Input
   ============================================ */
.vin-input-container {
    display: flex;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.vin-input {
    flex: 1;
    min-width: 250px;
    padding: 1rem 1.25rem;
    font-size: 1.1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    font-family: 'Inter', monospace;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    transition: var(--transition);
}

.vin-input:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

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

/* ============================================
   Search Box
   ============================================ */
.search-box {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 0.75rem 1rem;
    margin-bottom: 1.5rem;
    transition: var(--transition);
}

.search-box:focus-within {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.search-box .material-icons {
    color: var(--text-tertiary);
}

.search-box input {
    flex: 1;
    border: none;
    outline: none;
    font-size: 1rem;
    background: transparent;
    color: var(--text-primary);
    caret-color: var(--primary);
}

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

/* ============================================
   Grid List (Brands, Models)
   ============================================ */
.grid-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 0.75rem;
}

.grid-item {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.grid-item:hover {
    border-color: var(--primary);
    background: rgba(37, 99, 235, 0.05);
}

.grid-item img {
    width: 60px;
    height: 60px;
    object-fit: contain;
}

.grid-item .name {
    font-weight: 500;
    font-size: 0.9rem;
}

.grid-item .count {
    font-size: 0.8rem;
    color: var(--text-tertiary);
}

/* ============================================
   Card List (Vehicles, Groups)
   ============================================ */
.card-list {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.card-item {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.card-item:hover {
    border-color: var(--primary);
    background: rgba(37, 99, 235, 0.05);
}

.card-item .icon {
    width: 48px;
    height: 48px;
    background: var(--bg-tertiary);
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.card-item .icon .material-icons {
    color: var(--primary);
    font-size: 1.5rem;
}

.card-item .icon img {
    width: 100%;
    height: 100%;
    object-fit: contain;
    border-radius: var(--radius-sm);
}

.card-item .content {
    flex: 1;
    min-width: 0;
}

.card-item .title {
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.25rem;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.card-item .subtitle {
    font-size: 0.85rem;
    color: var(--text-secondary);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.car-year-badge {
    display: inline-block;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--primary);
    background: rgba(37, 99, 235, 0.15);
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-sm);
    margin-top: 0.35rem;
}

.car-badges {
    display: flex;
    flex-wrap: wrap;
    gap: 0.35rem;
    margin-top: 0.35rem;
}

.car-badge {
    display: inline-block;
    font-size: 0.7rem;
    font-weight: 600;
    padding: 0.15rem 0.45rem;
    border-radius: var(--radius-sm);
}

.car-badge-year {
    color: var(--primary);
    background: rgba(37, 99, 235, 0.15);
}

.car-badge-series {
    color: #10b981;
    background: rgba(16, 185, 129, 0.15);
}

.car-badge-engine {
    color: #f59e0b;
    background: rgba(245, 158, 11, 0.15);
}

.card-item .arrow {
    color: var(--text-tertiary);
}

/* ============================================
   Filters
   ============================================ */
.filters-container {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 1.5rem;
}

.filter-select {
    padding: 0.75rem 1rem;
    font-size: 0.95rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-secondary);
    cursor: pointer;
    transition: var(--transition);
    min-width: 150px;
    color: white;
}

.filter-select:focus {
    outline: none;
    border-color: var(--primary);
}

/* ============================================
   Breadcrumb
   ============================================ */
.breadcrumb {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 0.5rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.breadcrumb-item {
    color: var(--primary);
    cursor: pointer;
    transition: var(--transition);
}

.breadcrumb-item:hover {
    text-decoration: underline;
}

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

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

/* ============================================
   Schemas Container
   ============================================ */
.schemas-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 1rem;
}

.schema-card {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    cursor: pointer;
    transition: var(--transition);
}

.schema-card:hover {
    border-color: var(--primary);
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

.schema-card .schema-image {
    width: 100%;
    height: 200px;
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: hidden;
}

.schema-card .schema-image img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.schema-card .schema-image .material-icons {
    font-size: 4rem;
    color: var(--text-tertiary);
}

.schema-card .schema-info {
    padding: 1rem;
}

.schema-card .schema-name {
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

.schema-card .schema-description {
    font-size: 0.85rem;
    color: var(--text-secondary);
    white-space: pre-line;
    line-height: 1.4;
    max-height: 4.2em;
    overflow: hidden;
}

.schema-card .schema-parts {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    margin-top: 0.75rem;
    padding-top: 0.75rem;
    border-top: 1px solid var(--border-color);
}

.schema-card .part-tag {
    font-size: 0.75rem;
    padding: 0.25rem 0.5rem;
    background: rgba(37, 99, 235, 0.1);
    color: var(--primary);
    border-radius: var(--radius-sm);
}

/* ============================================
   Schema Image Container (Parts View)
   ============================================ */
.schema-image-container {
    margin-bottom: 1.5rem;
}

.schema-image-container .schema-diagram {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem;
    text-align: center;
}

.schema-image-container .schema-diagram img {
    max-width: 100%;
    max-height: 400px;
    object-fit: contain;
}

.schema-image-container .schema-diagram-info {
    margin-top: 1rem;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    text-align: left;
}

.schema-image-container .schema-diagram-info h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
}

.schema-image-container .schema-diagram-info p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    white-space: pre-line;
}

/* ============================================
   Parts List Container
   ============================================ */
.parts-list-container {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.part-item {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1rem 1.25rem;
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    transition: var(--transition);
}

.part-item:hover {
    border-color: var(--primary-light);
}

.part-item .part-index {
    width: 32px;
    height: 32px;
    background: var(--primary);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.85rem;
    flex-shrink: 0;
}

.part-item .part-content {
    flex: 1;
    min-width: 0;
}

.part-item .part-name {
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.25rem;
}

.part-item .part-number {
    font-family: monospace;
    font-size: 0.9rem;
    color: var(--primary);
    background: rgba(37, 99, 235, 0.1);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    display: inline-block;
    margin-bottom: 0.25rem;
}

.part-item .part-details {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

.part-item .part-notice {
    font-size: 0.8rem;
    color: var(--text-tertiary);
    font-style: italic;
    margin-top: 0.25rem;
}

.parts-section-divider {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 1rem 0;
    margin: 0.5rem 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 500;
}

.parts-section-divider .material-icons {
    font-size: 1.1rem;
    color: var(--text-tertiary);
}

.part-item-additional {
    opacity: 0.85;
}

.part-item-additional .part-index {
    background: var(--bg-tertiary);
    color: var(--text-tertiary);
}

/* Collapsible Part Groups */
.part-item-group {
    cursor: pointer;
    position: relative;
}

.part-item-group:hover {
    background: var(--bg-tertiary);
}

.part-item-group .part-expand-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 2rem;
    height: 2rem;
    color: var(--text-secondary);
    transition: transform 0.2s ease;
}

.part-item-group.expanded .part-expand-icon {
    transform: rotate(180deg);
}

.part-variants-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.25rem;
    font-size: 0.75rem;
    color: var(--primary);
    background: rgba(37, 99, 235, 0.15);
    padding: 0.2rem 0.5rem;
    border-radius: var(--radius-sm);
    margin-top: 0.25rem;
}

.part-variants-badge .material-icons {
    font-size: 0.875rem;
}

.part-variants-list {
    overflow: hidden;
    transition: max-height 0.3s ease, opacity 0.2s ease;
    max-height: 1000px;
    opacity: 1;
    margin-left: 2.5rem;
    border-left: 2px solid var(--primary);
    margin-bottom: 0.5rem;
}

.part-variants-list.collapsed {
    max-height: 0;
    opacity: 0;
    margin-bottom: 0;
}

.part-variant-item {
    display: flex;
    align-items: flex-start;
    gap: 0.75rem;
    padding: 0.75rem 1rem;
    background: var(--bg-tertiary);
    border-bottom: 1px solid var(--border-color);
}

.part-variant-item:last-child {
    border-bottom: none;
}

.part-variant-index {
    width: 1.5rem;
    height: 1.5rem;
    background: var(--bg-secondary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 500;
    font-size: 0.75rem;
    color: var(--text-secondary);
    flex-shrink: 0;
}

.part-variant-item .part-content {
    flex: 1;
    min-width: 0;
}

.part-variant-item .part-name {
    font-weight: 500;
    font-size: 0.9rem;
}

.part-variant-item .part-number {
    font-size: 0.8rem;
}

/* Clickable Part Items */
.part-item-clickable {
    cursor: pointer;
}

.part-item-clickable:hover {
    background: var(--bg-tertiary);
}

.part-chevron {
    display: flex;
    align-items: center;
    color: var(--text-tertiary);
}

.part-chevron .material-icons {
    font-size: 1.25rem;
}

/* ============================================
   Part Details Modal
   ============================================ */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(4px);
    z-index: 1000;
    display: flex;
    align-items: flex-end;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.modal-overlay.active {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: var(--bg-primary);
    width: 100%;
    max-width: 500px;
    max-height: 85vh;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
    display: flex;
    flex-direction: column;
    transform: translateY(100%);
    transition: transform 0.3s ease;
}

.modal-overlay.active .modal-content {
    transform: translateY(0);
}

@media (min-width: 768px) {
    .modal-overlay {
        align-items: center;
    }
    
    .modal-content {
        max-height: 80vh;
        border-radius: var(--radius-lg);
        transform: translateY(20px) scale(0.95);
    }
    
    .modal-overlay.active .modal-content {
        transform: translateY(0) scale(1);
    }
}

.modal-header {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    padding: 1.25rem 1.5rem;
    border-bottom: 1px solid var(--border-color);
    gap: 1rem;
}

.modal-title-section {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    flex: 1;
    min-width: 0;
}

.modal-position {
    width: 2.5rem;
    height: 2.5rem;
    background: var(--primary);
    color: white;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 1rem;
    flex-shrink: 0;
}

.modal-header h3 {
    font-size: 1.1rem;
    font-weight: 600;
    margin: 0;
    color: var(--text-primary);
}

.modal-part-number {
    font-family: 'Roboto Mono', monospace;
    font-size: 0.9rem;
    color: var(--primary);
    margin-top: 0.25rem;
}

.modal-close {
    background: var(--bg-tertiary);
    border: none;
    width: 2.5rem;
    height: 2.5rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--text-secondary);
    transition: var(--transition);
    flex-shrink: 0;
}

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

.modal-body {
    flex: 1;
    overflow-y: auto;
    padding: 1rem 1.5rem 2rem;
}

.modal-section {
    margin-bottom: 1.25rem;
}

.modal-section:last-child {
    margin-bottom: 0;
}

.modal-section-header {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-weight: 600;
    font-size: 0.9rem;
    color: var(--text-primary);
    margin-bottom: 0.75rem;
}

.modal-section-header .material-icons {
    font-size: 1.1rem;
    color: var(--primary);
}

.modal-section-content {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

.modal-section-content.notice {
    background: var(--bg-tertiary);
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    border-left: 3px solid var(--primary);
}

.modal-chips {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.modal-chip {
    background: var(--bg-tertiary);
    padding: 0.375rem 0.75rem;
    border-radius: var(--radius-sm);
    font-size: 0.85rem;
    font-family: 'Roboto Mono', monospace;
    color: var(--text-secondary);
}

.modal-date {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 0.8rem;
    color: var(--text-tertiary);
    margin: 0.75rem 0;
}

.modal-date .material-icons {
    font-size: 1rem;
}

.modal-table-wrapper {
    overflow-x: auto;
    margin: 0 -0.5rem;
    padding: 0 0.5rem;
}

.modal-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 0.85rem;
}

.modal-table thead th {
    text-align: left;
    font-weight: 600;
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-tertiary);
    padding: 0.5rem 0.75rem;
    border-bottom: 2px solid var(--border-color);
}

.modal-table tbody tr {
    border-bottom: 1px solid var(--border-color);
}

.modal-table tbody tr:last-child {
    border-bottom: none;
}

.modal-table td {
    padding: 0.75rem;
    vertical-align: top;
}

.modal-td-name {
    font-weight: 500;
    color: var(--text-primary);
    min-width: 100px;
}

.modal-td-note {
    color: var(--text-secondary);
    font-family: 'Roboto Mono', monospace;
    font-size: 0.8rem;
}

.modal-td-qty {
    text-align: center;
    color: var(--text-secondary);
    font-weight: 500;
    min-width: 40px;
}

.modal-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--primary);
    text-decoration: none;
    font-size: 0.9rem;
    padding: 0.5rem 1rem;
    background: rgba(37, 99, 235, 0.1);
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.modal-link:hover {
    background: rgba(37, 99, 235, 0.2);
}

.modal-empty {
    text-align: center;
    color: var(--text-tertiary);
    padding: 2rem;
}

.part-item .part-quantity {
    font-size: 0.85rem;
    color: var(--text-secondary);
    background: var(--bg-tertiary);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
}

/* ============================================
   Parts Container (Old - kept for compatibility)
   ============================================ */
.parts-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 1rem;
}

.part-card {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: var(--transition);
}

.part-card:hover {
    box-shadow: var(--shadow-md);
}

.part-card .part-image {
    width: 100%;
    height: 150px;
    background: var(--bg-tertiary);
    display: flex;
    align-items: center;
    justify-content: center;
}

.part-card .part-image img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

.part-card .part-image .material-icons {
    font-size: 3rem;
    color: var(--text-tertiary);
}

.part-card .part-info {
    padding: 1rem;
}

.part-card .part-name {
    font-weight: 600;
    font-size: 1rem;
    margin-bottom: 0.5rem;
}

.part-card .part-number {
    font-family: monospace;
    font-size: 0.9rem;
    color: var(--primary);
    background: rgba(37, 99, 235, 0.1);
    padding: 0.25rem 0.5rem;
    border-radius: var(--radius-sm);
    display: inline-block;
    margin-bottom: 0.5rem;
}

.part-card .part-details {
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* ============================================
   Results Container (VIN)
   ============================================ */
.results-container {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.result-card {
    background: var(--bg-secondary);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 1.25rem;
    cursor: pointer;
    transition: var(--transition);
}

.result-card:hover {
    border-color: var(--primary);
    background: rgba(37, 99, 235, 0.05);
}

.result-card .brand {
    font-size: 0.85rem;
    color: var(--primary);
    font-weight: 500;
    margin-bottom: 0.25rem;
}

.result-card .title {
    font-size: 1.1rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.result-card .details {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ============================================
   Loading Overlay
   ============================================ */
.loading-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.9);
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    z-index: 1000;
}

.loading-overlay.active {
    display: flex;
}

.loading-spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border-color);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

.loading-overlay p {
    color: var(--text-secondary);
    font-weight: 500;
}

/* ============================================
   Toast Notification
   ============================================ */
.toast {
    position: fixed;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: var(--text-primary);
    color: white;
    padding: 1rem 1.5rem;
    border-radius: var(--radius-md);
    font-weight: 500;
    z-index: 1001;
    transition: transform 0.3s ease;
    box-shadow: var(--shadow-xl);
}

.toast.active {
    transform: translateX(-50%) translateY(0);
}

.toast.error {
    background: var(--error);
}

/* ============================================
   Empty State
   ============================================ */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    color: var(--text-secondary);
}

.empty-state .material-icons {
    font-size: 4rem;
    color: var(--text-tertiary);
    margin-bottom: 1rem;
}

.empty-state h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 768px) {
    .header {
        padding: 0.875rem 1rem;
    }
    
    .header h1 {
        font-size: 1.1rem;
    }
    
    .main {
        padding: 1rem;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .search-options {
        grid-template-columns: 1fr;
    }
    
    .search-card {
        padding: 1.5rem;
    }
    
    .search-card .material-icons {
        font-size: 2.5rem;
    }
    
    .vin-input-container {
        flex-direction: column;
    }
    
    .vin-input {
        min-width: unset;
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .grid-list {
        grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
        gap: 0.5rem;
    }
    
    .grid-item {
        padding: 0.75rem;
    }
    
    .grid-item img {
        width: 40px;
        height: 40px;
    }
    
    .grid-item .name {
        font-size: 0.8rem;
    }
    
    .parts-container {
        grid-template-columns: 1fr;
    }
    
    .filters-container {
        flex-direction: column;
    }
    
    .filter-select {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .header-content {
        justify-content: center;
    }
    
    .card-item {
        padding: 0.875rem;
    }
    
    .card-item .icon {
        width: 40px;
        height: 40px;
    }
}

/* ============================================
   Dark Mode (optional - follows system)
   ============================================ */
@media (prefers-color-scheme: dark) {
    :root {
        --bg-primary: #0f172a;
        --bg-secondary: #1e293b;
        --bg-tertiary: #334155;
        
        --text-primary: #f1f5f9;
        --text-secondary: #94a3b8;
        --text-tertiary: #64748b;
        
        --border-color: #334155;
    }
    
    .loading-overlay {
        background: rgba(15, 23, 42, 0.95);
    }
}

/* ============================================
   Image Zoom Modal
   ============================================ */
.zoom-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.95);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.2s ease, visibility 0.2s ease;
}

.zoom-overlay.active {
    opacity: 1;
    visibility: visible;
}

.zoom-close {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: rgba(0, 0, 0, 0.95);
    border: none;
    width: 3rem;
    height: 3rem;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: white;
    transition: background 0.2s ease;
    z-index: 10;
}

.zoom-close:hover {
    background: rgba(18, 77, 204, 0.842);
}

.zoom-hint {
    position: absolute;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(0, 0, 0, 0.7);
    color: rgba(255, 255, 255, 0.8);
    padding: 0.5rem 1rem;
    border-radius: var(--radius-full);
    font-size: 0.85rem;
    z-index: 10;
    pointer-events: none;
    opacity: 1;
    transition: opacity 0.3s ease;
}

.zoom-hint .material-icons {
    font-size: 1.1rem;
}

.zoom-overlay.dragging .zoom-hint {
    opacity: 0;
}

.zoom-container {
    width: 100%;
    height: 100%;
    overflow: hidden;
    cursor: grab;
    display: flex;
    align-items: center;
    justify-content: center;
}

.zoom-container.dragging {
    cursor: grabbing;
}

.zoom-container img {
    max-width: none;
    max-height: none;
    transform-origin: center center;
    transition: transform 0.1s ease;
    user-select: none;
    -webkit-user-drag: none;
}

/* Make schema diagram clickable */
.schema-diagram {
    cursor: zoom-in;
    transition: opacity 0.2s ease;
}

.schema-diagram:hover {
    opacity: 0.9;
}

.schema-diagram img {
    pointer-events: auto;
}