/* ==================== 全局样式 ==================== */
:root {
    /* 户外运动品牌配色 - Forest Green 系 */
    --primary: #2d5016;
    --primary-dark: #1f3a0f;
    --primary-light: #3d6b21;
    
    --accent: #d97706;
    --accent-light: #f59e0b;
    
    --text-primary: #1a1a1a;
    --text-secondary: #525252;
    --text-tertiary: #737373;
    
    --bg-base: #fafaf9;
    --bg-elevated: #ffffff;
    --bg-subtle: #f5f5f4;
    
    --border: #e7e5e4;
    --border-light: #f5f5f4;
    
    --success: #16a34a;
    --warning: #ea580c;
    --error: #dc2626;
    --info: #0891b2;
    
    /* 阴影 - 克制的层级感 */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.04);
    --shadow-md: 0 2px 8px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 4px 16px rgba(0, 0, 0, 0.08);
    
    /* 圆角 */
    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 18px;
    
    /* 动画时长 */
    --transition-fast: 150ms;
    --transition-normal: 200ms;
    --transition-slow: 250ms;
}

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

body {
    font-family: 'Inter', -apple-system, 'Noto Sans SC', sans-serif;
    background: var(--bg-base);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    /* 轻微纸质纹理 */
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(45, 80, 22, 0.015) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(45, 80, 22, 0.015) 0%, transparent 50%);
}

/* ==================== 顶部导航 ==================== */
.header {
    background: var(--bg-elevated);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(12px);
    background: rgba(255, 255, 255, 0.95);
}

.header-content {
    max-width: 1920px;
    margin: 0 auto;
    padding: 16px 32px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 32px;
}

.header-left {
    display: flex;
    align-items: center;
    gap: 32px;
    flex: 1;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    color: var(--primary);
    cursor: pointer;
}

.logo svg {
    color: var(--primary);
}

.logo-text {
    font-size: 18px;
    font-weight: 700;
    letter-spacing: 0.5px;
    text-transform: uppercase;
}

.search-box {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-subtle);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-sm);
    padding: 10px 16px;
    max-width: 420px;
    width: 100%;
    transition: all var(--transition-normal);
}

.search-box:focus-within {
    background: var(--bg-elevated);
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(45, 80, 22, 0.08);
}

.search-box svg {
    color: var(--text-tertiary);
    flex-shrink: 0;
}

.search-box input {
    border: none;
    background: none;
    outline: none;
    flex: 1;
    font-size: 14px;
    color: var(--text-primary);
}

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

.header-right {
    display: flex;
    align-items: center;
    gap: 16px;
}

.budget-overview {
    display: flex;
    gap: 8px;
}

.budget-pill,
.weight-pill {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-subtle);
    border: 1px solid var(--border);
    border-radius: 24px;
    padding: 6px 14px;
}

.budget-pill .label,
.weight-pill .label {
    font-size: 12px;
    color: var(--text-tertiary);
    font-weight: 500;
}

.budget-pill .value,
.weight-pill .value {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}

/* ==================== 按钮系统 ==================== */
.btn-primary {
    background: var(--primary);
    color: white;
    border: none;
    border-radius: var(--radius-sm);
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    display: inline-flex;
    align-items: center;
    gap: 8px;
    position: relative;
}

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

.btn-primary:active {
    transform: translateY(0);
    box-shadow: var(--shadow-sm);
}

.btn-secondary {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    padding: 9px 18px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

.btn-secondary:active {
    transform: scale(0.98);
}

.btn-export {
    background: transparent;
    color: var(--primary);
    border: 1px solid var(--primary);
    border-radius: var(--radius-sm);
    padding: 8px 16px;
    font-size: 13px;
    font-weight: 600;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all var(--transition-normal);
}

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

.full-width {
    width: 100%;
    justify-content: center;
}

/* ==================== 主体布局 ==================== */
.main-container {
    max-width: 1920px;
    margin: 0 auto;
    padding: 32px;
    display: grid;
    grid-template-columns: 280px 1fr 360px;
    gap: 32px;
    align-items: start;
}

/* ==================== 左侧步骤导航 ==================== */
.stepper-sidebar {
    background: var(--bg-elevated);
    border-radius: var(--radius-md);
    padding: 24px;
    border: 1px solid var(--border);
    position: sticky;
    top: 96px;
}

.sidebar-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 16px;
}

.riding-purpose {
    margin-bottom: 28px;
    padding-bottom: 28px;
    border-bottom: 1px solid var(--border-light);
}

.purpose-select {
    width: 100%;
    padding: 10px 14px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--bg-base);
    font-size: 14px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

.purpose-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(45, 80, 22, 0.08);
}

.steps-container {
    margin-bottom: 28px;
}

.step-list {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.step-item {
    display: flex;
    gap: 12px;
    padding: 12px 8px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    transition: all var(--transition-fast);
    position: relative;
}

.step-item:hover {
    background: var(--bg-subtle);
}

.step-item.active {
    background: rgba(45, 80, 22, 0.06);
}

.step-indicator {
    display: flex;
    flex-direction: column;
    align-items: center;
    flex-shrink: 0;
}

.step-number {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--bg-subtle);
    border: 2px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 600;
    color: var(--text-tertiary);
    transition: all var(--transition-normal);
}

.step-item.active .step-number {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
}

.step-line {
    width: 2px;
    flex: 1;
    background: var(--border-light);
    margin: 4px 0;
    min-height: 24px;
}

.step-content {
    flex: 1;
    padding-top: 2px;
}

.step-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 4px;
}

.step-name {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
}

.step-status {
    color: var(--text-tertiary);
}

.step-status.complete {
    color: var(--success);
}

.step-item.active .step-status {
    color: var(--primary);
}

.step-hint {
    font-size: 12px;
    color: var(--text-tertiary);
}

/* ==================== 装配信息 ==================== */
.assembly-info {
    background: var(--bg-subtle);
    border-radius: var(--radius-sm);
    padding: 16px;
}

.assembly-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
}

.assembly-detail {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

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

.assembly-label {
    font-size: 12px;
    color: var(--text-tertiary);
}

.assembly-value {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
}

.difficulty-medium {
    color: var(--accent);
    background: rgba(217, 119, 6, 0.1);
    padding: 2px 8px;
    border-radius: 4px;
}

/* ==================== 中间配件区域 ==================== */
.parts-section {
    background: transparent;
}

.section-header {
    margin-bottom: 24px;
}

.section-title-row {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 28px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.5px;
}

.parts-count {
    font-size: 14px;
    color: var(--text-tertiary);
    background: var(--bg-subtle);
    padding: 4px 12px;
    border-radius: 16px;
}

.filter-sort-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
}

.filter-group {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
}

.filter-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 16px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

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

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

.filter-tag {
    display: flex;
    align-items: center;
    gap: 6px;
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: 16px;
    padding: 4px 12px;
    font-size: 13px;
    color: var(--text-secondary);
}

.remove-filter {
    background: none;
    border: none;
    color: var(--text-tertiary);
    font-size: 16px;
    cursor: pointer;
    padding: 0;
    line-height: 1;
    transition: color var(--transition-fast);
}

.remove-filter:hover {
    color: var(--error);
}

.sort-group {
    display: flex;
    align-items: center;
    gap: 8px;
}

.sort-label {
    font-size: 14px;
    color: var(--text-tertiary);
    font-weight: 500;
}

.sort-select {
    padding: 8px 12px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    background: var(--bg-elevated);
    font-size: 14px;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-normal);
}

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

.sort-select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(45, 80, 22, 0.08);
}

/* ==================== 配件卡片 ==================== */
.parts-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 20px;
}

.part-card {
    background: var(--bg-elevated);
    border: 2px solid var(--border);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: all var(--transition-normal);
    position: relative;
    cursor: pointer;
}

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

.part-card.selected {
    border-color: var(--primary);
    background: rgba(45, 80, 22, 0.02);
}

.part-card.selected::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--primary);
}

.part-badge {
    position: absolute;
    top: 12px;
    right: 12px;
    padding: 4px 10px;
    border-radius: 6px;
    font-size: 11px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.3px;
    z-index: 10;
    backdrop-filter: blur(8px);
}

.part-badge.recommended {
    background: rgba(45, 80, 22, 0.9);
    color: white;
}

.part-badge.stock-low {
    background: rgba(234, 88, 12, 0.9);
    color: white;
}

.part-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
    background: var(--bg-subtle);
    position: relative;
}

.part-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

.part-card:hover .part-image img {
    transform: scale(1.05);
}

.part-info {
    padding: 20px;
}

.part-name {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 10px;
    line-height: 1.4;
}

.part-specs {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    margin-bottom: 12px;
}

.spec-item {
    font-size: 12px;
    color: var(--text-tertiary);
    background: var(--bg-subtle);
    padding: 4px 10px;
    border-radius: 6px;
    font-weight: 500;
}

.part-tags {
    margin-bottom: 12px;
}

.tag-compatible {
    display: inline-block;
    font-size: 11px;
    color: var(--success);
    background: rgba(22, 163, 74, 0.08);
    border: 1px solid rgba(22, 163, 74, 0.2);
    padding: 3px 8px;
    border-radius: 4px;
    font-weight: 500;
}

.part-reason {
    display: flex;
    align-items: flex-start;
    gap: 8px;
    padding: 10px;
    background: rgba(45, 80, 22, 0.04);
    border-left: 2px solid var(--primary);
    border-radius: 4px;
}

.part-reason svg {
    color: var(--primary);
    flex-shrink: 0;
    margin-top: 2px;
}

.part-reason span {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.5;
}

.part-footer {
    padding: 16px 20px;
    border-top: 1px solid var(--border-light);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 16px;
}

.part-stats {
    display: flex;
    gap: 20px;
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.stat-label {
    font-size: 11px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.3px;
    font-weight: 500;
}

.stat-value {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}

.stat-value.price {
    color: var(--primary);
}

.btn-select {
    padding: 8px 18px;
    background: var(--bg-subtle);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

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

.btn-select.selected-btn {
    background: var(--primary);
    border-color: var(--primary);
    color: white;
    display: flex;
    align-items: center;
    gap: 6px;
}

.compare-checkbox {
    position: absolute;
    top: 12px;
    left: 12px;
    display: flex;
    align-items: center;
    gap: 6px;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(8px);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 6px 10px;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.compare-checkbox:hover {
    background: white;
    border-color: var(--primary);
    color: var(--primary);
}

.compare-checkbox input {
    cursor: pointer;
}

/* ==================== 右侧汇总面板 ==================== */
.summary-sidebar {
    background: var(--bg-elevated);
    border: 1px solid var(--border);
    border-radius: var(--radius-md);
    padding: 24px;
    position: sticky;
    top: 96px;
    display: flex;
    flex-direction: column;
    gap: 24px;
}

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

.summary-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
}

.summary-overview {
    background: var(--bg-subtle);
    border-radius: var(--radius-sm);
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

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

.overview-row.total {
    padding-bottom: 16px;
    border-bottom: 1px solid var(--border);
}

.overview-label {
    font-size: 14px;
    color: var(--text-secondary);
    font-weight: 500;
}

.overview-value {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    font-variant-numeric: tabular-nums;
}

.overview-row.total .overview-value {
    font-size: 24px;
    color: var(--primary);
}

.match-score {
    display: flex;
    align-items: center;
    gap: 12px;
    flex: 1;
    margin-left: 16px;
}

.match-bar {
    flex: 1;
    height: 6px;
    background: var(--border-light);
    border-radius: 3px;
    overflow: hidden;
}

.match-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--primary), var(--primary-light));
    border-radius: 3px;
    transition: width var(--transition-slow);
}

.match-value {
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
    min-width: 40px;
    text-align: right;
}

/* ==================== 兼容性提示 ==================== */
.compatibility-section {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.section-subtitle {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
}

.compatibility-alerts {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.alert-item {
    display: flex;
    gap: 12px;
    padding: 14px;
    border-radius: var(--radius-sm);
    border: 1px solid;
}

.alert-item.warning {
    background: rgba(234, 88, 12, 0.04);
    border-color: rgba(234, 88, 12, 0.2);
}

.alert-item.info {
    background: rgba(8, 145, 178, 0.04);
    border-color: rgba(8, 145, 178, 0.2);
}

.alert-item.error {
    background: rgba(220, 38, 38, 0.04);
    border-color: rgba(220, 38, 38, 0.2);
}

.alert-icon {
    flex-shrink: 0;
}

.alert-item.warning .alert-icon {
    color: var(--warning);
}

.alert-item.info .alert-icon {
    color: var(--info);
}

.alert-item.error .alert-icon {
    color: var(--error);
}

.alert-content {
    flex: 1;
}

.alert-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.alert-desc {
    font-size: 12px;
    color: var(--text-secondary);
    line-height: 1.5;
    margin-bottom: 8px;
}

.alert-action {
    background: none;
    border: none;
    color: var(--primary);
    font-size: 12px;
    font-weight: 600;
    cursor: pointer;
    padding: 0;
    transition: opacity var(--transition-fast);
}

.alert-action:hover {
    opacity: 0.8;
}

/* ==================== 已选配件清单 ==================== */
.selected-parts {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.parts-badge {
    font-size: 11px;
    background: var(--primary);
    color: white;
    padding: 3px 8px;
    border-radius: 10px;
    margin-left: 8px;
    font-weight: 600;
}

.selected-list {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.selected-item {
    background: var(--bg-subtle);
    border-radius: var(--radius-sm);
    padding: 14px;
    display: flex;
    justify-content: space-between;
    gap: 12px;
}

.selected-info {
    flex: 1;
}

.selected-category {
    font-size: 11px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 600;
    margin-bottom: 4px;
}

.selected-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.selected-specs {
    font-size: 12px;
    color: var(--text-secondary);
}

.selected-actions {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 8px;
}

.selected-price {
    font-size: 15px;
    font-weight: 700;
    color: var(--primary);
    font-variant-numeric: tabular-nums;
}

.btn-change {
    background: none;
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 4px 12px;
    font-size: 12px;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all var(--transition-fast);
}

.btn-change:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(45, 80, 22, 0.04);
}

/* ==================== CTA 按钮区 ==================== */
.summary-actions {
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding-top: 8px;
    border-top: 1px solid var(--border);
}

/* ==================== 对比面板 ==================== */
.compare-panel {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-elevated);
    border-top: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    z-index: 200;
    max-height: 60vh;
    overflow-y: auto;
}

.compare-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 32px;
    border-bottom: 1px solid var(--border);
}

.compare-header h3 {
    font-size: 18px;
    font-weight: 700;
}

.close-compare {
    background: none;
    border: none;
    color: var(--text-tertiary);
    cursor: pointer;
    padding: 4px;
    transition: color var(--transition-fast);
}

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

.compare-content {
    padding: 32px;
}

.compare-table {
    width: 100%;
    border-collapse: collapse;
}

.compare-table th,
.compare-table td {
    padding: 12px 16px;
    text-align: left;
    border-bottom: 1px solid var(--border-light);
}

.compare-table th {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.3px;
    background: var(--bg-subtle);
}

.compare-table td {
    font-size: 14px;
    color: var(--text-primary);
}

.compare-table td.highlight {
    background: rgba(45, 80, 22, 0.06);
    font-weight: 600;
    color: var(--primary);
}

/* ==================== 移动端底部汇总栏 ==================== */
.mobile-summary-bar {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--bg-elevated);
    border-top: 1px solid var(--border);
    padding: 16px 20px;
    z-index: 150;
    box-shadow: 0 -4px 16px rgba(0, 0, 0, 0.08);
    align-items: center;
    justify-content: space-between;
    gap: 16px;
}

.mobile-summary-info {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.mobile-price {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
    font-variant-numeric: tabular-nums;
}

.mobile-weight {
    font-size: 13px;
    color: var(--text-tertiary);
    font-weight: 500;
}

/* ==================== 响应式设计 ==================== */
@media (max-width: 1440px) {
    .main-container {
        grid-template-columns: 260px 1fr 340px;
        gap: 24px;
    }
}

@media (max-width: 1200px) {
    .main-container {
        grid-template-columns: 240px 1fr 320px;
        gap: 20px;
        padding: 24px;
    }
    
    .parts-grid {
        grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    }
}

@media (max-width: 1024px) {
    .header-content {
        padding: 14px 24px;
    }
    
    .budget-overview {
        display: none;
    }
    
    .main-container {
        grid-template-columns: 1fr 320px;
        gap: 20px;
    }
    
    .stepper-sidebar {
        display: none;
    }
}

@media (max-width: 768px) {
    .header-content {
        flex-wrap: wrap;
        gap: 16px;
    }
    
    .header-left {
        width: 100%;
        flex-wrap: wrap;
    }
    
    .search-box {
        max-width: 100%;
    }
    
    .header-right {
        width: 100%;
        justify-content: flex-end;
    }
    
    .main-container {
        grid-template-columns: 1fr;
        padding: 16px;
        gap: 16px;
        padding-bottom: 100px;
    }
    
    .summary-sidebar {
        display: none;
    }
    
    .mobile-summary-bar {
        display: flex;
    }
    
    .parts-grid {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        font-size: 24px;
    }
    
    .filter-sort-bar {
        flex-direction: column;
        align-items: stretch;
    }
    
    .sort-group {
        justify-content: space-between;
    }
}

@media (max-width: 480px) {
    .logo-text {
        display: none;
    }
    
    .btn-secondary {
        padding: 8px 12px;
        font-size: 13px;
    }
    
    .section-title {
        font-size: 20px;
    }
    
    .part-card {
        border-radius: var(--radius-sm);
    }
}

/* ==================== 微动效 ==================== */
@media (prefers-reduced-motion: no-preference) {
    .part-card,
    .btn-primary,
    .btn-secondary,
    .step-item {
        will-change: transform;
    }
}