/* 成都嘉美地毯 - 专业网站CSS样式表 v1.0 */
/* 设计原则：专业、现代、B2B、响应式 */

/* ===== CSS Reset & Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* 品牌主色调 */
    --primary-blue: #2C5AA0;      /* 专业蓝 - 信任感 */
    --primary-dark: #1A365D;      /* 深蓝 - 稳重感 */
    --accent-gold: #D4AF37;       /* 金 - 高端感 */
    --success-green: #38A169;     /* 绿 - 环保感 */
    --light-gray: #F7FAFC;        /* 浅灰 - 背景色 */
    --medium-gray: #E2E8F0;       /* 中灰 - 边框色 */
    --dark-gray: #2D3748;         /* 深灰 - 文字色 */
    --text-light: #718096;        /* 浅文字色 */
    
    /* 尺寸变量 */
    --container-width: 1200px;
    --container-padding: 20px;
    --header-height: 80px;
    --header-height-scrolled: 70px;
    --section-padding: 80px;
    --mobile-breakpoint: 768px;
    --tablet-breakpoint: 1024px;
    
    /* 动画速度 */
    --animation-fast: 0.3s;
    --animation-medium: 0.5s;
    --animation-slow: 0.8s;
    
    /* 阴影 */
    --shadow-light: 0 2px 10px rgba(0, 0, 0, 0.1);
    --shadow-medium: 0 4px 20px rgba(0, 0, 0, 0.15);
    --shadow-heavy: 0 8px 30px rgba(0, 0, 0, 0.2);
    
    /* 圆角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 20px;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--dark-gray);
    background-color: white;
    overflow-x: hidden;
}

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

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
    color: var(--primary-dark);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p {
    margin-bottom: 1rem;
    font-size: 1rem;
    color: var(--text-light);
}

a {
    color: var(--primary-blue);
    text-decoration: none;
    transition: color var(--animation-fast) ease;
}

a:hover {
    color: var(--primary-dark);
}

/* ===== Buttons ===== */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-size: 1rem;
    text-align: center;
    cursor: pointer;
    transition: all var(--animation-fast) ease;
    border: 2px solid transparent;
    min-width: 140px;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.btn-secondary {
    background-color: var(--success-green);
    color: white;
}

.btn-secondary:hover {
    background-color: #2F855A;
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-blue);
    border-color: var(--primary-blue);
}

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

/* ===== 1. TOP NAVIGATION ===== */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: var(--header-height);
    background-color: white;
    box-shadow: var(--shadow-light);
    z-index: 1000;
    transition: all var(--animation-fast) ease;
}

.main-header.scrolled {
    height: var(--header-height-scrolled);
    box-shadow: var(--shadow-medium);
}

.main-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

/* Logo */
.logo a {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.logo h1 {
    font-size: 1.5rem;
    margin-bottom: 4px;
    color: var(--primary-dark);
}

.logo-subtitle {
    font-size: 0.85rem;
    color: var(--text-light);
    margin: 0;
}

/* Main Navigation */
.nav-list {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--dark-gray);
    font-weight: 500;
    font-size: 1rem;
    padding: 8px 0;
    position: relative;
}

.nav-link:hover,
.nav-link.active {
    color: var(--primary-blue);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 2px;
    background-color: var(--primary-blue);
}

/* Dropdown Menu */
.dropdown {
    position: relative;
}

.dropdown-menu {
    position: absolute;
    top: 100%;
    left: 0;
    min-width: 200px;
    background-color: white;
    box-shadow: var(--shadow-heavy);
    border-radius: var(--radius-md);
    padding: 12px 0;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: all var(--animation-fast) ease;
    z-index: 1001;
}

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

.dropdown-menu a {
    display: block;
    padding: 10px 20px;
    color: var(--dark-gray);
    font-size: 0.95rem;
}

.dropdown-menu a:hover {
    background-color: var(--light-gray);
    color: var(--primary-blue);
}

/* Mobile Menu Toggle */
.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: var(--dark-gray);
    cursor: pointer;
    padding: 8px;
}

/* ===== 2. HERO SECTION ===== */
.hero-section {
    height: 100vh;
    min-height: 600px;
    position: relative;
    margin-top: var(--header-height);
}

.hero-swiper {
    height: 100%;
    width: 100%;
}

.hero-slide {
    position: relative;
    height: 100%;
    display: flex;
    align-items: center;
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
}

.slide-1 {
    background-color: #1A365D; /* 备用背景色，实际会用图片 */
    background-image: linear-gradient(rgba(26, 54, 93, 0.9), rgba(26, 54, 93, 0.7));
}

.slide-2 {
    background-color: #2C5AA0;
    background-image: linear-gradient(rgba(44, 90, 160, 0.9), rgba(44, 90, 160, 0.7));
}

.slide-3 {
    background-color: #1A365D;
    background-image: linear-gradient(rgba(38, 169, 105, 0.9), rgba(38, 169, 105, 0.7));
}

.slide-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(to right, rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.3));
}

.hero-content {
    position: relative;
    z-index: 2;
    color: white;
    max-width: 800px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    color: white;
    line-height: 1.2;
}

.hero-subtitle {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    color: rgba(255, 255, 255, 0.9);
}

.hero-buttons {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* Swiper Controls */
.swiper-button-next,
.swiper-button-prev {
    color: white !important;
}

.swiper-pagination-bullet {
    background-color: rgba(255, 255, 255, 0.5) !important;
    opacity: 1 !important;
}

.swiper-pagination-bullet-active {
    background-color: white !important;
}

/* ===== 3. ADVANTAGES SECTION ===== */
.advantages-section {
    padding: var(--section-padding) 0;
    background-color: var(--light-gray);
}

.section-header {
    text-align: center;
    margin-bottom: 4rem;
}

.section-title {
    font-size: 2.5rem;
    margin-bottom: 1rem;
    color: var(--primary-dark);
}

.section-subtitle {
    font-size: 1.25rem;
    color: var(--text-light);
    max-width: 600px;
    margin: 0 auto;
}

.advantages-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.advantage-card {
    background-color: white;
    padding: 2rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-light);
    text-align: center;
    transition: transform var(--animation-medium) ease, box-shadow var(--animation-medium) ease;
}

.advantage-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-medium);
}

.advantage-icon {
    font-size: 3rem;
    color: var(--primary-blue);
    margin-bottom: 1.5rem;
}

.advantage-title {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: var(--primary-dark);
}

.advantage-description {
    font-size: 1rem;
    color: var(--text-light);
    line-height: 1.6;
}

/* ===== 4. PRODUCTS SECTION ===== */
.products-section {
    padding: var(--section-padding) 0;
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.product-card {
    background-color: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-light);
    transition: transform var(--animation-medium) ease, box-shadow var(--animation-medium) ease;
}

.product-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

.product-image {
    height: 200px;
    background-color: var(--light-gray);
    display: flex;
    align-items: center;
    justify-content: center;
}

.image-placeholder {
    text-align: center;
    color: var(--text-light);
}

.image-placeholder i {
    font-size: 4rem;
    margin-bottom: 1rem;
    color: var(--primary-blue);
}

.product-content {
    padding: 1.5rem;
}

.product-title {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
    color: var(--primary-dark);
}

.product-subtitle {
    font-size: 1rem;
    color: var(--text-light);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.product-features {
    list-style: none;
    margin-bottom: 1.5rem;
}

.product-features li {
    display: flex;
    align-items: flex-start;
    margin-bottom: 0.75rem;
    font-size: 0.95rem;
    color: var(--dark-gray);
}

.product-features i {
    color: var(--success-green);
    margin-right: 0.75rem;
    margin-top: 0.2rem;
    flex-shrink: 0;
}

.product-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

/* ===== 产品详细技术参数样式 ===== */
.product-technical-details {
    margin-top: 4rem;
    padding-top: 3rem;
    border-top: 2px solid var(--medium-gray);
}

.technical-section {
    background-color: white;
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-light);
}

.technical-title {
    font-size: 1.25rem;
    color: var(--primary-dark);
    margin-bottom: 1.25rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.technical-title i {
    color: var(--primary-blue);
}

.specs-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 1rem;
}

.spec-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.75rem 1rem;
    background-color: var(--light-gray);
    border-radius: var(--radius-md);
    border-left: 3px solid var(--success-green);
}

.spec-label {
    font-weight: 600;
    color: var(--primary-dark);
    font-size: 0.95rem;
}

.spec-value {
    color: var(--text-light);
    font-size: 0.9rem;
    text-align: right;
    max-width: 60%;
}

/* ===== 5. APPLICATIONS SECTION ===== */
.applications-section {
    padding: var(--section-padding) 0;
    background-color: var(--light-gray);
}

.tab-nav {
    display: flex;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.tab-button {
    padding: 12px 24px;
    background-color: white;
    border: 2px solid var(--medium-gray);
    border-radius: var(--radius-md);
    color: var(--dark-gray);
    font-weight: 500;
    cursor: pointer;
    transition: all var(--animation-fast) ease;
}

.tab-button:hover {
    border-color: var(--primary-blue);
    color: var(--primary-blue);
}

.tab-button.active {
    background-color: var(--primary-blue);
    border-color: var(--primary-blue);
    color: white;
}

.case-study {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    background-color: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-light);
}

.case-image {
    min-height: 300px;
    background-color: var(--light-gray);
    display: flex;
    align-items: center;
    justify-content: center;
}

.case-details {
    padding: 2rem;
}

.case-title {
    font-size: 1.75rem;
    margin-bottom: 1.5rem;
    color: var(--primary-dark);
}

.case-info {
    margin-bottom: 1.5rem;
}

.info-item {
    display: flex;
    margin-bottom: 0.75rem;
}

.info-label {
    font-weight: 600;
    color: var(--primary-dark);
    min-width: 100px;
}

.info-value {
    color: var(--dark-gray);
}

.case-description {
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.client-testimonial {
    background-color: var(--light-gray);
    border-left: 4px solid var(--accent-gold);
    padding: 1rem 1.5rem;
    margin-bottom: 1.5rem;
    border-radius: var(--radius-md);
    font-style: italic;
    position: relative;
}

.client-testimonial::before {
    content: '"';
    font-size: 3rem;
    color: var(--accent-gold);
    position: absolute;
    top: -10px;
    left: 10px;
    opacity: 0.3;
}

.client-testimonial p {
    margin: 0;
    color: var(--dark-gray);
    font-size: 0.95rem;
}

.client-testimonial strong {
    color: var(--primary-dark);
}

/* ===== 6. PROCESS SECTION ===== */
.process-section {
    padding: var(--section-padding) 0;
}

.process-timeline {
    max-width: 800px;
    margin: 0 auto;
}

.process-step {
    display: flex;
    align-items: flex-start;
    margin-bottom: 3rem;
    position: relative;
}

.process-step:last-child {
    margin-bottom: 0;
}

.process-step::before {
    content: '';
    position: absolute;
    left: 25px;
    top: 50px;
    bottom: -50px;
    width: 2px;
    background-color: var(--medium-gray);
}

.process-step:last-child::before {
    display: none;
}

.step-number {
    width: 50px;
    height: 50px;
    background-color: var(--primary-blue);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 600;
    margin-right: 2rem;
    flex-shrink: 0;
    position: relative;
    z-index: 1;
}

.step-content {
    flex: 1;
}

.step-title {
    font-size: 1.5rem;
    margin-bottom: 0.75rem;
    color: var(--primary-dark);
}

.step-description {
    color: var(--text-light);
    line-height: 1.6;
    margin-bottom: 1rem;
}

.process-details {
    background-color: var(--light-gray);
    border-radius: var(--radius-md);
    padding: 1rem;
    margin: 1rem 0;
}

.detail-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.detail-item i {
    color: var(--primary-blue);
    width: 16px;
    text-align: center;
}

.detail-item strong {
    color: var(--primary-dark);
    margin-right: 0.25rem;
}

/* ===== 7. TRUST SECTION ===== */
.trust-section {
    padding: var(--section-padding) 0;
    background-color: var(--light-gray);
}

.trust-content {
    max-width: 1000px;
    margin: 0 auto;
}

.trust-subtitle {
    font-size: 1.75rem;
    margin-bottom: 2rem;
    color: var(--primary-dark);
    text-align: center;
}

.cert-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.cert-item {
    background-color: white;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow-light);
}

.cert-icon {
    font-size: 2.5rem;
    color: var(--primary-blue);
    margin-bottom: 1rem;
}

.cert-name {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
    color: var(--primary-dark);
}

.cert-desc {
    color: var(--text-light);
    font-size: 0.95rem;
    margin-bottom: 0.5rem;
}

.cert-details {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    margin-top: 0.5rem;
}

.cert-info {
    font-size: 0.8rem;
    color: var(--text-light);
    display: flex;
    justify-content: space-between;
}

.cert-info strong {
    color: var(--primary-dark);
    margin-right: 0.5rem;
    min-width: 60px;
}

.partner-name {
    font-size: 0.9rem;
    color: var(--primary-dark);
    margin-top: 0.5rem;
    font-weight: 600;
}

.partners-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    gap: 1.5rem;
}

.partner-logo {
    background-color: white;
    padding: 1.5rem;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 120px;
    box-shadow: var(--shadow-light);
}

.logo-placeholder {
    color: var(--text-light);
    font-size: 0.9rem;
    text-align: center;
}

/* ===== 8. FOOTER SECTION ===== */
.main-footer {
    background-color: var(--primary-dark);
    color: white;
    padding: 4rem 0 2rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-bottom: 3rem;
}

.footer-title {
    font-size: 1.5rem;
    margin-bottom: 1.5rem;
    color: white;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    margin-bottom: 1rem;
    color: rgba(255, 255, 255, 0.8);
}

.contact-item i {
    margin-right: 0.75rem;
    margin-top: 0.2rem;
    color: var(--accent-gold);
    flex-shrink: 0;
}

.contact-item a {
    color: rgba(255, 255, 255, 0.8);
}

.contact-item a:hover {
    color: white;
}

.footer-links {
    list-style: none;
}

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

.footer-links a {
    color: rgba(255, 255, 255, 0.8);
}

.footer-links a:hover {
    color: white;
}

.qr-code-placeholder {
    background-color: white;
    padding: 1.5rem;
    border-radius: var(--radius-md);
    text-align: center;
    margin-bottom: 1rem;
    color: var(--dark-gray);
}

.qr-icon {
    font-size: 3rem;
    color: var(--success-green);
    margin-bottom: 0.75rem;
}

.wechat-id {
    color: rgba(255, 255, 255, 0.8);
    font-size: 0.95rem;
    text-align: center;
}

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

.copyright p {
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
}

.back-to-top-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background-color: var(--primary-blue);
    color: white;
    border-radius: 50%;
    transition: background-color var(--animation-fast) ease;
}

.back-to-top-btn:hover {
    background-color: var(--accent-gold);
}

/* ===== FLOATING BUTTONS ===== */
.floating-buttons {
    position: fixed;
    right: 30px;
    bottom: 30px;
    z-index: 999;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.floating-phone,
.floating-sample {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 180px;
    height: 50px;
    background-color: var(--primary-blue);
    color: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-heavy);
    text-decoration: none;
    font-weight: 600;
    transition: all var(--animation-fast) ease;
}

.floating-phone:hover,
.floating-sample:hover {
    background-color: var(--primary-dark);
    transform: scale(1.05);
}

.floating-sample {
    background-color: var(--success-green);
}

.floating-sample:hover {
    background-color: #2F855A;
}

.floating-phone i,
.floating-sample i {
    margin-right: 10px;
    font-size: 1.2rem;
}

/* ===== RESPONSIVE DESIGN ===== */
@media (max-width: 1024px) {
    :root {
        --section-padding: 60px;
    }
    
    .hero-title {
        font-size: 2.8rem;
    }
    
    .case-study {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 768px) {
    :root {
        --section-padding: 40px;
        --header-height: 70px;
        --header-height-scrolled: 60px;
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .main-nav {
        position: fixed;
        top: var(--header-height);
        left: 0;
        right: 0;
        background-color: white;
        box-shadow: var(--shadow-medium);
        padding: 1rem;
        transform: translateY(-100%);
        opacity: 0;
        visibility: hidden;
        transition: all var(--animation-medium) ease;
    }
    
    .main-nav.active {
        transform: translateY(0);
        opacity: 1;
        visibility: visible;
    }
    
    .nav-list {
        flex-direction: column;
        gap: 0;
    }
    
    .nav-link {
        display: block;
        padding: 12px 0;
        border-bottom: 1px solid var(--medium-gray);
    }
    
    .dropdown-menu {
        position: static;
        box-shadow: none;
        background-color: var(--light-gray);
        border-radius: 0;
        opacity: 1;
        visibility: visible;
        transform: none;
        padding: 0;
        margin-left: 1rem;
        margin-top: 0.5rem;
        margin-bottom: 0.5rem;
    }
    
    .hero-title {
        font-size: 2.2rem;
    }
    
    .hero-subtitle {
        font-size: 1.1rem;
    }
    
    .hero-buttons {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .btn {
        width: 100%;
    }
    
    .process-step {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }
    
    .step-number {
        margin-right: 0;
        margin-bottom: 1rem;
    }
    
    .process-step::before {
        left: 50%;
        margin-left: -1px;
    }
    
    .floating-buttons {
        right: 15px;
        bottom: 15px;
    }
    
    .floating-phone,
    .floating-sample {
        width: 50px;
        height: 50px;
        padding: 0;
    }
    
    .floating-phone span,
    .floating-sample span {
        display: none;
    }
    
    .floating-phone i,
    .floating-sample i {
        margin-right: 0;
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.8rem;
    }
    
    .section-title {
        font-size: 1.8rem;
    }
    
    .advantages-grid,
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .contact-item {
        justify-content: center;
    }
    
    .footer-bottom {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}

/* ===== ACCESSIBILITY ===== */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}

/* ===== PRINT STYLES ===== */
@media print {
    .main-header,
    .floating-buttons,
    .hero-buttons,
    .product-actions,
    .back-to-top {
        display: none !important;
    }
    
    body {
        background-color: white !important;
        color: black !important;
    }
    
    .container {
        max-width: 100% !important;
        padding: 0 !important;
    }
    
    a {
        color: black !important;
        text-decoration: underline !important;
    }
}

/* ===== 技术文档下载页面样式 ===== */
.downloads-section {
    padding: 80px 0;
}

.download-category {
    margin-bottom: 3rem;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.download-card {
    background-color: white;
    border-radius: var(--radius-lg);
    padding: 2rem;
    box-shadow: var(--shadow-light);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
}

.download-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-medium);
}

.download-icon {
    width: 60px;
    height: 60px;
    background-color: var(--primary-light);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
}

.download-icon i {
    font-size: 1.5rem;
    color: var(--primary-blue);
}

.download-title {
    font-size: 1.5rem;
    color: var(--primary-dark);
    margin-bottom: 1rem;
    line-height: 1.3;
}

.download-desc {
    color: var(--text-light);
    line-height: 1.6;
    margin-bottom: 1.5rem;
    flex-grow: 1;
}

.download-info {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 1.5rem;
    font-size: 0.9rem;
    color: var(--medium-gray);
}

.download-info span {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.download-info i {
    color: var(--primary-blue);
}

.download-card .btn {
    align-self: flex-start;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.help-section {
    background-color: var(--light-gray);
    padding: 60px 0;
}

.help-tips {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.help-tip {
    background-color: white;
    border-radius: var(--radius-lg);
    padding: 1.5rem;
    box-shadow: var(--shadow-light);
}

.help-tip h3 {
    font-size: 1.25rem;
    color: var(--primary-dark);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.help-tip h3 i {
    color: var(--accent-gold);
}

.help-tip p {
    color: var(--text-light);
    line-height: 1.6;
}

/* 响应式调整 */
@media (max-width: 768px) {
    .download-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .download-card {
        padding: 1.5rem;
    }
    
    .download-icon {
        width: 50px;
        height: 50px;
        margin-bottom: 1rem;
    }
    
    .download-title {
        font-size: 1.3rem;
    }
    
    .help-tips {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}

@media (max-width: 480px) {
    .download-info {
        flex-direction: column;
        gap: 0.5rem;
    }
}