/* 全局变量 */
:root {
    --primary-color: #007aff;
    --secondary-color: #5ac8fa;
    --dark-color: #1c1c1e;
    --light-color: #f2f2f7;
    --success-color: #34c759;
    --warning-color: #ff9500;
    --danger-color: #ff3b30;
    --gray-color: #8e8e93;
    --white-color: #ffffff;
    --black-color: #000000;
    --transition: all 0.3s ease;
    --shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
    --radius: 8px;
}

/* 基础样式 */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    font-size: 62.5%;
    scroll-behavior: smooth;
}

body {
    font-family: "SF Pro Display", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Open Sans", "Helvetica Neue", sans-serif;
    font-size: 1.6rem;
    line-height: 1.6;
    color: var(--dark-color);
    background-color: var(--white-color);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: var(--transition);
}

a:hover {
    color: var(--secondary-color);
}

ul {
    list-style: none;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: 1rem;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    width: 100%;
    max-width: 1200px;
    padding: 0 2rem;
    margin: 0 auto;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 1.2rem 2.4rem;
    border-radius: var(--radius);
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
    font-size: 1.6rem;
}

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

.btn-primary:hover {
    background-color: #0062cc;
    color: var(--white-color);
}

.btn-secondary {
    background-color: var(--light-color);
    color: var(--dark-color);
}

.btn-secondary:hover {
    background-color: #e0e0e5;
    color: var(--dark-color);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border: 1px solid var(--primary-color);
}

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

/* 部分标题 */
.section-title {
    font-size: 3.2rem;
    text-align: center;
    margin-bottom: 4rem;
    position: relative;
    padding-bottom: 1rem;
}

.section-title:after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 6rem;
    height: 3px;
    background-color: var(--primary-color);
}

/* 头部样式 */
.header {
    position: sticky;
    top: 0;
    left: 0;
    width: 100%;
    background-color: var(--white-color);
    box-shadow: var(--shadow);
    z-index: 100;
    padding: 1.5rem 0;
}

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

.company-name {
    flex: 1;
}

.company-name a {
    font-size: 1.8rem;
    font-weight: bold;
    color: var(--primary-color);
    text-decoration: none;
}

.logo {
    flex: 1;
}

.logo img {
    max-height: 5rem;
}

.main-nav {
    flex: 3;
    display: flex;
    justify-content: center;
}

.main-nav ul {
    display: flex;
}

.main-nav ul li {
    margin: 0 1rem;
}

.main-nav ul li a {
    color: var(--dark-color);
    font-weight: 500;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
}

.main-nav ul li a:hover,
.main-nav ul li a.active {
    color: var(--primary-color);
}

.language-switcher {
    flex: 1;
    display: flex;
    justify-content: flex-end;
    align-items: center;
}

.language-btn {
    background: none;
    border: none;
    padding: 0.5rem 1rem;
    color: var(--gray-color);
    cursor: pointer;
    margin-left: 1rem;
    font-size: 1.4rem;
    border-radius: var(--radius);
    transition: var(--transition);
}

.language-btn:hover {
    background-color: var(--light-color);
    color: var(--dark-color);
}

.mobile-menu-btn {
    display: none;
    cursor: pointer;
}

.mobile-menu-btn span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--dark-color);
    margin: 5px 0;
    transition: var(--transition);
}

/* 英雄区域 */
.hero {
    padding: 8rem 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

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

.hero-content {
    flex: 1;
    padding-right: 3rem;
}

.hero-content.full-width {
    flex: 1;
    padding-right: 0;
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.hero-content h1 {
    font-size: 4.2rem;
    margin-bottom: 2rem;
    color: var(--dark-color);
}

.hero-content p {
    font-size: 1.8rem;
    color: var(--gray-color);
    margin-bottom: 3rem;
}

.hero-btns .btn {
    margin-right: 1.5rem;
    margin-bottom: 1rem;
}

.hero-image {
    flex: 1;
    text-align: center;
}

/* 服务区域 */
.services {
    padding: 8rem 0;
    background-color: var(--white-color);
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(30rem, 1fr));
    grid-gap: 3rem;
}

.service-card {
    background-color: var(--white-color);
    border-radius: var(--radius);
    padding: 3rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
    text-align: center;
}

.service-card:hover {
    transform: translateY(-5px);
}

.service-icon {
    margin-bottom: 2rem;
    font-size: 3.6rem;
    color: var(--primary-color);
}

.service-card h3 {
    font-size: 2.2rem;
    margin-bottom: 1.5rem;
}

.service-card p {
    color: var(--gray-color);
}

/* 产品展示 */
.featured-products {
    padding: 8rem 0;
    background-color: var(--light-color);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(30rem, 1fr));
    grid-gap: 3rem;
}

.product-card {
    background-color: var(--white-color);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.product-card:hover {
    transform: translateY(-5px);
}

.product-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.product-card h3 {
    padding: 2rem 2rem 1rem;
    font-size: 2.2rem;
}

.product-card p {
    padding: 0 2rem 2rem;
    color: var(--gray-color);
}

.product-card .btn {
    margin: 0 2rem 2rem;
}

/* 客户评价 */
.testimonials {
    padding: 8rem 0;
    background-color: var(--white-color);
}

.testimonials-slider {
    max-width: 80rem;
    margin: 0 auto;
}

.testimonial {
    background-color: var(--light-color);
    border-radius: var(--radius);
    padding: 3rem;
    box-shadow: var(--shadow);
}

.testimonial-content {
    margin-bottom: 2rem;
    position: relative;
    font-style: italic;
}

.testimonial-content:before {
    content: '\201C';
    font-size: 6rem;
    color: var(--primary-color);
    opacity: 0.2;
    position: absolute;
    top: -2rem;
    left: -1rem;
}

.testimonial-author {
    display: flex;
    align-items: center;
}

.testimonial-author img {
    width: 5rem;
    height: 5rem;
    border-radius: 50%;
    margin-right: 1.5rem;
}

.author-info h4 {
    margin-bottom: 0.5rem;
}

.author-info p {
    color: var(--gray-color);
    font-size: 1.4rem;
}

/* CTA 区域 */
.cta {
    padding: 8rem 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--secondary-color) 100%);
    text-align: center;
    color: var(--white-color);
}

.cta h2 {
    font-size: 3.2rem;
    margin-bottom: 2rem;
}

.cta p {
    max-width: 70rem;
    margin: 0 auto 3rem;
    font-size: 1.8rem;
}

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

.cta .btn:hover {
    background-color: var(--light-color);
}

/* 页脚 */
.footer {
    background-color: var(--dark-color);
    color: var(--light-color);
    padding: 6rem 0 3rem;
}

.footer-content {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 2fr;
    grid-gap: 3rem;
    margin-bottom: 3rem;
}

.footer-company h3 {
    color: var(--white-color);
    font-size: 2rem;
    margin-bottom: 2rem;
}

.footer-company p {
    color: var(--gray-color);
}

.footer-logo img {
    max-height: 5rem;
    margin-bottom: 2rem;
}

.footer-logo p {
    color: var(--gray-color);
}

.footer-links h3 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    color: var(--white-color);
}

.footer-links ul li {
    margin-bottom: 1rem;
}

.footer-links ul li a {
    color: var(--gray-color);
    transition: var(--transition);
}

.footer-links ul li a:hover {
    color: var(--white-color);
    padding-left: 0.5rem;
}

.footer-contact h3 {
    font-size: 1.8rem;
    margin-bottom: 2rem;
    color: var(--white-color);
}

.footer-contact p {
    display: flex;
    align-items: center;
    margin-bottom: 1.5rem;
    color: var(--gray-color);
}

.footer-contact p i {
    margin-right: 1rem;
    color: var(--primary-color);
}

.footer-contact p a {
    color: var(--gray-color);
}

.footer-contact p a:hover {
    color: var(--white-color);
}

.social-icons {
    display: flex;
    margin-top: 2rem;
}

.social-icons a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 4rem;
    height: 4rem;
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    margin-right: 1rem;
    transition: var(--transition);
}

.social-icons a:hover {
    background-color: var(--primary-color);
}

.social-icons a i {
    color: var(--white-color);
    font-size: 1.8rem;
}

.footer-bottom {
    text-align: center;
    padding-top: 3rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    color: var(--gray-color);
}

/* 响应式设计 */
@media screen and (max-width: 992px) {
    html {
        font-size: 60%;
    }

    .hero .container {
        flex-direction: column;
    }

    .hero-content, .hero-content.full-width {
        padding-right: 0;
        margin-bottom: 4rem;
        text-align: center;
    }

    .footer-content {
        grid-template-columns: 1fr 1fr;
        grid-row-gap: 4rem;
    }
}

@media screen and (max-width: 768px) {
    html {
        font-size: 57.5%;
    }

    .main-nav {
        display: none;
    }

    .mobile-menu-btn {
        display: block;
    }

    .language-switcher {
        position: absolute;
        top: 100%;
        right: 2rem;
        background-color: var(--white-color);
        padding: 1rem;
        border-radius: var(--radius);
        box-shadow: var(--shadow);
        display: none;
    }

    .language-switcher.active {
        display: flex;
    }

    .services-grid,
    .products-grid {
        grid-template-columns: 1fr;
        max-width: 50rem;
        margin: 0 auto;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }
}

@media screen and (max-width: 576px) {
    html {
        font-size: 55%;
    }

    .hero-content h1 {
        font-size: 3.6rem;
    }

    .section-title {
        font-size: 2.8rem;
    }
}

/* 动画 */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.5s ease forwards;
}