/* ==========================================================================
   1. 基础重置与全局变量 (Reset & Custom Properties)
   ========================================================================== */
:root {
    /* 核心色彩规划 */
    --primary-red: #8B2500;       /* 玛瑙红褐色（无硫八角自然干透色） */
    --primary-red-hover: #A03000; /* 悬停红 */
    --eco-green: #2E4F4F;         /* 生态绿（广西大山八角林色） */
    --eco-green-hover: #0E2F2F;   /* 悬停绿 */
    --bg-warm: #FDFBF7;           /* 温暖米白大背景 */
    --bg-white: #FFFFFF;
    --text-main: #1C1917;         /* 接近黑的深石色，保证高可读性 */
    --text-muted: #78716C;        /* 柔和灰色，用于描述 */
    --border-color: #E7E5E4;

    /* 字体与间距 */
    --font-main: 'Inter', system-ui, -apple-system, sans-serif;
    --container-width: 1200px;
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-main);
    background-color: var(--bg-warm);
    color: var(--text-main);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

.container {
    width: 100%;
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* 统一的按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.8rem 2rem;
    font-size: 0.95rem;
    font-weight: 500;
    border-radius: 4px;
    text-decoration: none;
    cursor: pointer;
    transition: var(--transition-smooth);
    border: 1px solid transparent;
}

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

.btn-primary:hover {
    background-color: var(--primary-red-hover);
    transform: translateY(-2px);
}

.btn-outline {
    background-color: transparent;
    border-color: var(--bg-white);
    color: var(--bg-white);
}

.btn-outline:hover {
    background-color: var(--bg-white);
    color: var(--primary-red);
    transform: translateY(-2px);
}

.btn-quote {
    background-color: transparent;
    border-color: var(--primary-red);
    color: var(--primary-red);
    width: 100%;
}

.btn-quote:hover {
    background-color: var(--primary-red);
    color: var(--bg-white);
}

/* 统一的板块标题区 */
.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-tag {
    display: block;
    color: var(--eco-green);
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.15em;
    margin-bottom: 0.75rem;
}

.section-title {
    font-size: 2.25rem;
    font-weight: 700;
    color: var(--text-main);
    letter-spacing: -0.02em;
}

/* ==========================================================================
   2. 导航栏样式 (Navbar)
   ========================================================================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background-color: rgba(253, 251, 247, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
}

.navbar .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-left, .nav-right {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    color: var(--text-main);
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 400;
    transition: var(--transition-smooth);
}

.nav-link:hover {
    color: var(--primary-red);
}

.logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    text-align: center;
}

.logo-mark {
    color: var(--primary-red);
    font-size: 1.5rem;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo-main {
    font-weight: 700;
    font-size: 1.2rem;
    letter-spacing: 0.05em;
    color: var(--text-main);
}

.logo-sub {
    font-size: 0.6rem;
    letter-spacing: 0.1em;
    color: var(--text-muted);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.lang-wrapper {
    position: relative;
}

.lang-switch {
    background: none;
    border: 1px solid var(--border-color);
    padding: 0.4rem 0.8rem;
    border-radius: 4px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.25rem;
    font-family: var(--font-main);
    font-size: 0.85rem;
    transition: var(--transition-smooth);
}

.lang-switch:hover {
    border-color: var(--primary-red);
    color: var(--primary-red);
}

.lang-dropdown {
    position: absolute;
    top: calc(100% + 8px);
    right: 0;
    background: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 0.5rem;
    min-width: 140px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.1);
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: var(--transition-smooth);
    z-index: 100;
}

.lang-dropdown.active {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-option {
    display: block;
    width: 100%;
    padding: 0.5rem 0.75rem;
    background: none;
    border: none;
    text-align: left;
    cursor: pointer;
    font-size: 0.85rem;
    font-family: var(--font-main);
    color: var(--text-main);
    border-radius: 2px;
    transition: var(--transition-smooth);
}

.lang-option:hover,
.lang-option.active {
    background-color: var(--bg-warm);
    color: var(--primary-red);
}

.btn-nav {
    background-color: var(--eco-green);
    color: var(--bg-white);
    padding: 0.6rem 1.25rem;
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 4px;
    text-decoration: none;
    transition: var(--transition-smooth);
}

.btn-nav:hover {
    background-color: var(--eco-green-hover);
}

/* Mobile Menu */
.mobile-menu-btn {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
    z-index: 1001;
}

.mobile-menu-btn span {
    width: 22px;
    height: 1.5px;
    background: var(--text-main);
    transition: var(--transition-smooth);
}

.mobile-menu-btn.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-btn.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-btn.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
}

.mobile-menu {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--bg-white);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 2rem;
    z-index: 999;
    padding: 5rem 2rem;
}

.mobile-menu.active {
    display: flex;
}

.mobile-menu a {
    font-size: 1.5rem;
    text-decoration: none;
    color: var(--text-main);
    font-weight: 500;
    transition: var(--transition-smooth);
}

.mobile-menu a:hover {
    color: var(--primary-red);
}

/* ==========================================================================
   3. 首屏大图/视频样式 (Hero Section)
   ========================================================================== */
.hero {
    position: relative;
    height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: var(--bg-white);
    padding-top: 80px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    background: #1A1513;
    overflow: hidden;
}

.hero-video {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(180deg, rgba(26,21,19,0.5) 0%, rgba(26,21,19,0.7) 100%);
    z-index: 1;
}

.hero-content {
    max-width: 850px;
    padding: 0 1.5rem;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background-color: rgba(46, 79, 79, 0.4);
    border: 1px solid rgba(255,255,255,0.2);
    padding: 0.5rem 1.25rem;
    border-radius: 50px;
    font-size: 0.8rem;
    font-weight: 600;
    letter-spacing: 0.1em;
    margin-bottom: 2rem;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.03em;
    margin-bottom: 1.5rem;
}

.hero-highlight {
    color: #FF7F50;
    display: block;
}

.hero-desc {
    font-size: 1.15rem;
    color: rgba(255,255,255,0.8);
    max-width: 650px;
    margin: 0 auto 3rem auto;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 4rem;
}

/* 数字看板样式 */
.hero-stats {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 3rem;
    padding-top: 2.5rem;
    border-top: 1px solid rgba(255,255,255,0.15);
}

.hero-stat {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.hero-stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--bg-white);
}

.hero-stat-label {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.6);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-top: 0.25rem;
}

.hero-stat-divider {
    width: 1px;
    height: 40px;
    background-color: rgba(255,255,255,0.2);
}

/* Scroll indicator */
.hero-scroll {
    position: absolute;
    bottom: 2rem;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.75rem;
    color: rgba(255,255,255,0.4);
    font-size: 0.7rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
}

.scroll-line {
    width: 1px;
    height: 30px;
    background: linear-gradient(to bottom, rgba(255,255,255,0.4), transparent);
    animation: scrollLine 2s ease-in-out infinite;
}

@keyframes scrollLine {
    0% { transform: scaleY(0); transform-origin: top; }
    50% { transform: scaleY(1); transform-origin: top; }
    51% { transform: scaleY(1); transform-origin: bottom; }
    100% { transform: scaleY(0); transform-origin: bottom; }
}

/* ==========================================================================
   4. 信任标章栏样式 (Trust Bar)
   ========================================================================== */
.trust-bar {
    background-color: var(--bg-white);
    padding: 2.5rem 0;
    border-bottom: 1px solid var(--border-color);
}

.trust-bar .container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.trust-item {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.trust-icon svg {
    flex-shrink: 0;
}

.trust-text {
    display: flex;
    flex-direction: column;
}

.trust-text strong {
    font-size: 1.05rem;
    color: var(--text-main);
}

.trust-text span {
    font-size: 0.85rem;
    color: var(--text-muted);
}

/* ==========================================================================
   5. 三大优势区样式 (Advantages)
   ========================================================================== */
.advantages {
    padding: 7rem 0;
    background-color: var(--bg-warm);
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2.5rem;
}

.advantage-card {
    background-color: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    padding: 2.5rem;
    text-align: center;
    transition: var(--transition-smooth);
}

.advantage-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(28,25,22,0.06);
}

.advantage-number {
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--primary-red);
    letter-spacing: 0.1em;
    margin-bottom: 1.5rem;
}

.advantage-icon {
    margin-bottom: 1.5rem;
}

.advantage-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-main);
}

.advantage-card p {
    font-size: 0.95rem;
    color: var(--text-muted);
    line-height: 1.6;
}

/* ==========================================================================
   6. 产品展示区样式 (Products Section)
   ========================================================================== */
.products {
    padding: 7rem 0;
    background-color: var(--bg-warm);
}

.product-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2.5rem;
    align-items: start; /* 卡片顶部对齐 */
}

.product-card {
    background-color: var(--bg-white);
    border: 1px solid var(--border-color);
    border-radius: 4px;
    overflow: hidden;
    transition: var(--transition-smooth);
    display: flex;
    flex-direction: column;
    height: 100%; /* 卡片高度填满 */
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 12px 30px rgba(28,25,22,0.06);
}

.product-image {
    position: relative;
    background-color: #F5F5F4;
    height: 260px;
    overflow: hidden;
}

.product-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
    loading: lazy;
}

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

/* 图片懒加载优化 */
img[loading="lazy"] {
    opacity: 0;
    transition: opacity 0.3s ease;
}

img[loading="lazy"].loaded {
    opacity: 1;
}

.img-placeholder {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    color: var(--text-muted);
    font-size: 0.85rem;
    letter-spacing: 0.05em;
}

.product-star {
    width: 60px;
    height: 60px;
    animation: spin 20s linear infinite;
}

@keyframes spin { 100% { transform: rotate(360deg); } }

.product-badge {
    position: absolute;
    top: 1rem;
    right: 1rem;
    background-color: var(--eco-green);
    color: var(--bg-white);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.25rem 0.75rem;
    border-radius: 2px;
}

.product-badge.value { background-color: #D97706; }
.product-badge.premium { background-color: var(--primary-red); }

.product-info {
    padding: 2rem;
    display: flex;
    flex-direction: column;
    flex: 1; /* 填满剩余空间 */
}

.product-grade {
    display: block;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--eco-green);
    margin-bottom: 0.5rem;
    letter-spacing: 0.05em;
}

.product-name {
    font-size: 1.3rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
    line-height: 1.3;
    min-height: 2.6rem; /* 固定名称高度 */
}

.product-specs {
    border-top: 1px dashed var(--border-color);
    border-bottom: 1px dashed var(--border-color);
    padding: 1rem 0;
    margin-bottom: 1.5rem;
}

.spec-item {
    display: flex;
    justify-content: space-between;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.spec-item:last-child { margin-bottom: 0; }

.spec-label { color: var(--text-muted); }
.spec-value { font-weight: 600; color: var(--text-main); }

.product-use {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 2rem;
    line-height: 1.5;
    flex: 1; /* 填满空间，把按钮推到底部 */
}

/* ==========================================================================
   7. 关于我们 (About)
   ========================================================================== */
.about {
    padding: 7rem 0;
    background-color: var(--bg-white);
    border-top: 1px solid var(--border-color);
}

.about-layout {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 5rem;
    align-items: center;
}

.about-content .section-tag {
    display: block;
    margin-bottom: 0.75rem;
}

.about-content .section-title {
    margin-bottom: 1.5rem;
}

.about-text {
    font-size: 1rem;
    color: var(--text-muted);
    line-height: 1.8;
    margin-bottom: 1rem;
}

.about-features {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    margin-top: 1.5rem;
}

.about-feature {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 0.95rem;
    font-weight: 500;
}

.about-feature-icon {
    color: var(--primary-red);
    font-size: 0.5rem;
}

.about-visual {
    position: relative;
}

.about-image-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

.about-img {
    aspect-ratio: 1;
    background-color: #F5F5F4;
    border-radius: 4px;
    overflow: hidden;
    position: relative;
}

.about-img img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.5s ease;
}

.about-img:hover img {
    transform: scale(1.05);
}

.about-img:nth-child(2) {
    transform: translateY(1.5rem);
}

.about-img:nth-child(3) {
    transform: translateY(-1.5rem);
}

/* ==========================================================================
   8. 质量与合规表格样式 (Quality & Compliance)
   ========================================================================== */
.quality {
    padding: 7rem 0;
    background-color: var(--bg-white);
    border-top: 1px solid var(--border-color);
}

.quality-grid {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 4rem;
}

.spec-table-wrapper {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.spec-table-wrapper h3, .quality-certs h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 1.5rem;
}

.spec-table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

.spec-table th, .spec-table td {
    padding: 1rem 1.25rem;
    border-bottom: 1px solid var(--border-color);
    font-size: 0.95rem;
}

.spec-table th {
    background-color: var(--bg-warm);
    font-weight: 600;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--text-muted);
}

.spec-pass {
    color: #15803D;
    font-weight: 600;
}

.cert-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.cert-card {
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    border-radius: 4px;
    background-color: var(--bg-warm);
}

.cert-icon {
    font-weight: 700;
    color: var(--primary-red);
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
}

.cert-card p {
    font-size: 0.85rem;
    color: var(--text-muted);
    margin-bottom: 1.25rem;
    line-height: 1.4;
}

.btn-download {
    font-size: 0.8rem;
    padding: 0.4rem 1rem;
    border: 1px solid var(--border-color);
    background-color: var(--bg-white);
    color: var(--text-main);
    cursor: pointer;
    font-family: var(--font-main);
    transition: var(--transition-smooth);
}

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

.btn-disabled {
    opacity: 0.5;
    cursor: not-allowed;
    pointer-events: none;
}

/* ==========================================================================
   9. 大宗询盘表单样式 (Wholesale Form)
   ========================================================================== */
.wholesale {
    padding: 7rem 0;
}

.wholesale-layout {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr;
    gap: 5rem;
    align-items: flex-start;
}

.wholesale-info .section-tag {
    display: block;
    margin-bottom: 0.75rem;
}

.wholesale-info .section-title {
    color: var(--text-main);
}

.wholesale-desc {
    font-size: 1.1rem;
    color: var(--text-muted);
    margin: 1.5rem 0 3rem 0;
    line-height: 1.7;
}

.wholesale-promises {
    display: flex;
    flex-direction: column;
    gap: 1.25rem;
}

.promise-item {
    display: flex;
    align-items: center;
    gap: 1rem;
    font-size: 1rem;
    font-weight: 500;
}

.promise-icon {
    color: var(--primary-red);
    font-size: 0.75rem;
}

.wholesale-form-wrapper {
    background-color: var(--bg-white);
    padding: 3rem;
    border-radius: 4px;
    border: 1px solid var(--border-color);
    box-shadow: 0 20px 40px rgba(28,25,22,0.04);
}

.wholesale-form h3 {
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 2rem;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

/* 确保所有表单元素对齐 */
.wholesale-form .form-group {
    display: flex;
    flex-direction: column;
}

.wholesale-form .form-group label {
    flex-shrink: 0;
}

.wholesale-form .form-group input,
.wholesale-form .form-group select,
.wholesale-form .form-group textarea {
    flex: 1;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    font-size: 0.85rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--text-main);
    min-height: 1.5rem; /* 固定标签高度，防止不同语言长度不一 */
    line-height: 1.5;
}

.form-group input, .form-group select, .form-group textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    background-color: var(--bg-warm);
    border-radius: 4px;
    font-family: var(--font-main);
    font-size: 0.95rem;
    color: var(--text-main);
    transition: var(--transition-smooth);
}

.form-group input:focus, .form-group select:focus, .form-group textarea:focus {
    outline: none;
    border-color: var(--primary-red);
    background-color: var(--bg-white);
}

.form-group textarea {
    resize: vertical;
    min-height: 80px;
}

.checkbox-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-top: 0.5rem;
}

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    font-size: 0.9rem !important;
    font-weight: 400 !important;
}

.checkbox-label input {
    width: auto;
    accent-color: var(--primary-red);
}

.btn-full {
    width: 100%;
    padding: 1rem;
    font-size: 1rem;
    margin-top: 1rem;
}

/* ==========================================================================
   10. 联系方式 (Contact)
   ========================================================================== */
.contact {
    padding: 5rem 0;
    background-color: var(--bg-white);
    border-top: 1px solid var(--border-color);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.contact-item {
    text-align: center;
    padding: 2rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
}

.contact-icon-wrapper {
    margin-bottom: 1rem;
}

.contact-item h4 {
    font-size: 0.8rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--text-muted);
    margin-bottom: 0.5rem;
    font-weight: 600;
}

.contact-item p {
    font-size: 0.95rem;
    color: var(--text-main);
    font-weight: 500;
}

/* ==========================================================================
   11. 页脚 (Footer)
   ========================================================================== */
.footer {
    background-color: #1C1917;
    color: var(--bg-white);
    padding: 5rem 0 2rem;
}

.footer-main {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 5rem;
    margin-bottom: 4rem;
}

.footer .logo-main {
    color: var(--bg-white);
}

.footer-desc {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.5);
    line-height: 1.7;
    margin-top: 1rem;
    max-width: 300px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2.5rem;
}

.footer-col h4 {
    font-size: 0.8rem;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    color: var(--primary-red);
    margin-bottom: 1.25rem;
    font-weight: 700;
}

.footer-col ul {
    list-style: none;
}

.footer-col li {
    margin-bottom: 0.75rem;
}

.footer-col a {
    font-size: 0.9rem;
    color: rgba(255,255,255,0.5);
    text-decoration: none;
    transition: var(--transition-smooth);
}

.footer-col a:hover {
    color: var(--bg-white);
}

.footer-bottom {
    padding-top: 2rem;
    border-top: 1px solid rgba(255,255,255,0.1);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.footer-bottom p {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.3);
}

.footer-social {
    display: flex;
    gap: 1.5rem;
}

.footer-social a {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.4);
    text-decoration: none;
    transition: var(--transition-smooth);
}

.footer-social a:hover {
    color: var(--primary-red);
}

/* ==========================================================================
   12. 全局交互与动画 (Global Interactions)
   ========================================================================== */
a, button {
    transition: var(--transition-smooth);
}

a:focus, button:focus {
    outline: 2px solid var(--primary-red);
    outline-offset: 2px;
}

::selection {
    background-color: var(--primary-red);
    color: var(--bg-white);
}

/* Scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-warm); }
::-webkit-scrollbar-thumb { background: var(--primary-red); border-radius: 3px; }

/* Preloader */
.preloader {
    position: fixed;
    inset: 0;
    background: #1C1917;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10000;
    transition: opacity 0.6s ease, visibility 0.6s;
}

.preloader.hidden {
    opacity: 0;
    visibility: hidden;
}

.preloader-star {
    font-size: 3rem;
    color: var(--primary-red);
    animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 0.3; transform: scale(0.8); }
    50% { opacity: 1; transform: scale(1.2); }
}

/* ==========================================================================
   13. 表单提交成功提示 (Form Success Message)
   ========================================================================== */
.form-success {
    background-color: #15803D;
    color: var(--bg-white);
    padding: 1rem 1.5rem;
    border-radius: 4px;
    margin-bottom: 1.5rem;
    font-weight: 500;
    display: none;
}

.form-success.show {
    display: block;
}

.form-error {
    background-color: #DC2626;
    color: var(--bg-white);
    padding: 1rem 1.5rem;
    border-radius: 4px;
    margin-bottom: 1.5rem;
    font-weight: 500;
    display: none;
}

.form-error.show {
    display: block;
}

/* ==========================================================================
   14. 响应式布局媒体查询 (Responsive Media Queries)
   ========================================================================== */
@media (max-width: 1024px) {
    .product-grid { grid-template-columns: repeat(2, 1fr); }
    .advantages-grid { grid-template-columns: repeat(2, 1fr); }
    .quality-grid { grid-template-columns: 1fr; gap: 3rem; }
    .wholesale-layout { grid-template-columns: 1fr; gap: 3rem; }
    .about-layout { grid-template-columns: 1fr; gap: 3rem; }
    .trust-bar .container { grid-template-columns: repeat(2, 1fr); gap: 1.5rem; }
    .contact-grid { grid-template-columns: repeat(2, 1fr); }
    .footer-main { grid-template-columns: 1fr; gap: 3rem; }

    .hero-stats { flex-direction: column; gap: 1.5rem; }
    .hero-stat-divider { width: 40px; height: 1px; }
}

@media (max-width: 768px) {
    html { font-size: 14px; }

    .nav-left, .nav-right .nav-link { display: none; }
    .mobile-menu-btn { display: flex; }

    .hero-title { font-size: 2.5rem; }
    .hero-actions { flex-direction: column; align-items: center; }
    .hero-actions .btn { width: 100%; max-width: 300px; }

    .product-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
    .advantages-grid { grid-template-columns: 1fr; }
    .cert-grid { grid-template-columns: 1fr; }
    .form-row { grid-template-columns: 1fr; gap: 0; }
    .checkbox-group { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .footer-links { grid-template-columns: 1fr; }
    .footer-bottom { flex-direction: column; gap: 1rem; text-align: center; }

    .wholesale-form-wrapper { padding: 2rem 1.5rem; }

    .about-img:nth-child(2),
    .about-img:nth-child(3) { transform: none; }
}

/* RTL Support */
[dir="rtl"] { direction: rtl; text-align: right; }
[dir="rtl"] .form-group label { text-align: right; }
[dir="rtl"] .form-group input, [dir="rtl"] .form-group select, [dir="rtl"] .form-group textarea { text-align: right; }
[dir="rtl"] .form-row { direction: rtl; }
[dir="rtl"] .product-card { direction: rtl; }

/* Print */
@media print {
    .navbar, .preloader, .hero-scroll, .mobile-menu, .mobile-menu-btn, .trust-bar { display: none !important; }
    body { color: #000; background: #fff; }
    .hero { min-height: auto; padding: 2rem 0; background: #f5f5f5; }
    .hero-content { text-align: left; }
    .hero-title { color: #000; }
    .hero-highlight { color: var(--primary-red); }
}