/* === V4 基本样式与变量 === */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@300;400;500;600;700&family=Noto+Sans+SC:wght@300;400;500;600;700&display=swap');

:root {
    /* 更现代的色彩方案 */
    --primary-color-v4: #10b981; /* Emerald 500 */
    --primary-light-v4: #6ee7b7; /* Emerald 300 */
    --primary-dark-v4: #047857; /* Emerald 700 */
    --secondary-color-v4: #4f46e5; /* Indigo 600 */
    --accent-color-v4: #f59e0b; /* Amber 500 */
    --light-bg-v4: #f0fdf4; /* Emerald 50 */
    --medium-bg-v4: #d1fae5; /* Emerald 100 */
    --white-v4: #ffffff;
    --dark-text-v4: #111827; /* Gray 900 - 更深色文字 */
    --medium-text-v4: #374151; /* Gray 700 - 更深色文字 */
    --light-text-v4: #6b7280; /* Gray 500 */
    --border-color-light-v4: #e5e7eb; /* Gray 200 */
    --border-color-medium-v4: #a7f3d0; /* Emerald 200 */
    --footer-bg-v4: #064e3b; /* Emerald 900 - 更深色底部 */
    --footer-text-v4: #a7f3d0; /* Emerald 200 */
    --footer-link-hover-v4: #ffffff;

    /* 更现代的字体 */
    --font-primary-v4: 'Poppins', 'Noto Sans SC', sans-serif;
    --font-secondary-v4: 'Noto Sans SC', sans-serif;

    /* 更精致的阴影 */
    --shadow-sm-v4: 0 4px 6px rgba(0, 0, 0, 0.05), 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md-v4: 0 10px 15px rgba(0, 0, 0, 0.07), 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-lg-v4: 0 20px 25px rgba(0, 0, 0, 0.1), 0 10px 10px rgba(0, 0, 0, 0.04);
    --shadow-xl-v4: 0 25px 50px rgba(0, 0, 0, 0.15), 0 10px 15px rgba(0, 0, 0, 0.05);

    /* 更现代的圆角 */
    --border-radius-base-v4: 8px;
    --border-radius-lg-v4: 16px;

    --transition-v4: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* === V4 重置与全局设置 === */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body.theme-v4 {
    font-family: var(--font-primary-v4);
    line-height: 1.7;
    color: var(--medium-text-v4);
    background-color: var(--white-v4);
    opacity: 1; /* Override default loading */
    transition: none; /* Override default loading */
}

body.theme-v4.loaded {
    opacity: 1;
}

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

section {
    padding: 5rem 0;
    position: relative;
    overflow: hidden;
}

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

a {
    color: var(--primary-color-v4);
    text-decoration: none;
    transition: var(--transition-v4);
}

a:hover {
    color: var(--primary-dark-v4);
}

ul {
    list-style: none;
}

h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-secondary-v4);
    color: var(--dark-text-v4);
    line-height: 1.3;
    font-weight: 700;
}

/* === V4 按钮样式 === */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.85rem 2rem;
    border-radius: var(--border-radius-base-v4);
    font-weight: 500;
    font-size: 0.95rem;
    transition: var(--transition-v4);
    cursor: pointer;
    border: none;
    text-transform: none;
    letter-spacing: 0.3px;
    position: relative;
    overflow: hidden;
}

.btn i {
    margin-left: 0.6rem;
    font-size: 0.9rem;
}

/* 添加按钮悬停特效 */
.btn-primary {
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    color: white;
    box-shadow: var(--shadow-sm-v4);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-md-v4);
    background: linear-gradient(135deg, var(--primary-dark-v4) 30%, var(--primary-color-v4) 100%);
}

.btn-primary::before {
    content: '';
    position: absolute;
    top: 0;
    left: -50%;
    width: 150%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transform: skewX(-20deg);
    transition: 0.75s ease;
    opacity: 0;
}

.btn-primary:hover::before {
    animation: shine 1.5s ease;
}

@keyframes shine {
    0% { left: -150%; opacity: 0.5; }
    100% { left: 150%; opacity: 0; }
}

.btn-outline {
    background: transparent;
    color: var(--primary-color-v4);
    border: 2px solid var(--primary-color-v4);
    position: relative;
    z-index: 1;
}

.btn-outline::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0%;
    height: 100%;
    background-color: var(--primary-color-v4);
    transition: width 0.3s ease;
    z-index: -1;
}

.btn-outline:hover {
    color: white;
    transform: translateY(-3px);
    box-shadow: var(--shadow-sm-v4);
}

.btn-outline:hover::after {
    width: 100%;
}

/* === V4 导航栏 === */
.header-v4 {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    z-index: 1000;
    padding: 1rem 0;
    transition: var(--transition-v4);
    border-bottom: 1px solid rgba(229, 231, 235, 0.5);
    box-shadow: none;
}

.header-v4.scrolled {
    padding: 0.7rem 0;
    box-shadow: var(--shadow-sm-v4); 
    background-color: rgba(255, 255, 255, 0.98);
}

.header-v4 .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-v4 .logo {
    display: flex;
    align-items: center;
}

.header-v4 .logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--dark-text-v4);
    margin-left: 0.6rem;
}

.header-v4 .logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    border-radius: var(--border-radius-base-v4);
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 1.2rem;
    box-shadow: var(--shadow-sm-v4);
}

.header-v4 .nav-links {
    display: flex;
    gap: 1.8rem;
}

.header-v4 .nav-links a {
    color: var(--medium-text-v4);
    font-weight: 500;
    position: relative;
    padding: 0.4rem 0;
    font-size: 0.9rem;
}

.header-v4 .nav-links a i {
    display: none; /* Hide icons on desktop nav */
}

.header-v4 .nav-links a:hover, 
.header-v4 .nav-links a.active {
    color: var(--primary-color-v4);
}

.header-v4 .nav-links a::after {
    content: '';
    position: absolute;
    width: 0;
    height: 2px;
    background: var(--primary-color-v4);
    bottom: -3px;
    left: 50%;
    transform: translateX(-50%);
    transition: width 0.3s ease;
    border-radius: 1px;
}

.header-v4 .nav-links a:hover::after, 
.header-v4 .nav-links a.active::after {
    width: 60%;
}

.header-v4 .mobile-menu {
    display: none;
    font-size: 1.4rem;
    cursor: pointer;
    color: var(--dark-text-v4);
}

/* === V4 英雄区域 === */
.hero-v4 {
    padding: 9rem 0 7rem;
    background: linear-gradient(160deg, var(--light-bg-v4) 0%, var(--medium-bg-v4) 100%);
    text-align: center;
    position: relative;
    overflow: hidden;
}

/* 添加背景元素 */
.hero-v4::before {
    content: '';
    position: absolute;
    top: -5%;
    right: -5%;
    width: 40%;
    height: 40%;
    background: linear-gradient(135deg, var(--primary-light-v4) 0%, transparent 70%);
    border-radius: 50%;
    opacity: 0.4;
    animation: float 15s ease-in-out infinite;
}

.hero-v4::after {
    content: '';
    position: absolute;
    bottom: -5%;
    left: -5%;
    width: 30%;
    height: 30%;
    background: linear-gradient(135deg, var(--primary-light-v4) 0%, transparent 70%);
    border-radius: 50%;
    opacity: 0.3;
    animation: float 18s ease-in-out infinite reverse;
}

@keyframes float {
    0% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-20px) rotate(5deg); }
    100% { transform: translateY(0) rotate(0deg); }
}

.hero-v4 .hero-content {
    max-width: 750px;
    margin: 0 auto;
    position: relative;
    z-index: 1;
}

.hero-v4 .hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
    color: var(--dark-text-v4);
    animation: fadeInUp 1s ease;
    background: linear-gradient(to right, var(--dark-text-v4), var(--primary-dark-v4));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    color: transparent;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero-v4 .hero-content p {
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
    color: var(--medium-text-v4);
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
    animation: fadeInUp 1s ease 0.2s;
    animation-fill-mode: both;
}

.hero-v4 .hero-buttons {
    display: flex;
    justify-content: center;
    gap: 1.2rem;
    animation: fadeInUp 1s ease 0.4s;
    animation-fill-mode: both;
}

/* === V4 关于我们 === */
.about-v4 {
    background-color: var(--white-v4);
}

.about-v4::before { display: none; } /* Override v1 pattern */

.about-v4 .about-content {
    display: grid;
    grid-template-columns: 0.9fr 1.1fr; /* Image slightly smaller */
    gap: 3rem;
    align-items: center;
}

.about-v4 .about-image {
    border-radius: var(--border-radius-lg-v4);
    overflow: hidden;
    box-shadow: var(--shadow-lg-v4);
}
.about-v4 .about-image::before { display: none; } /* Override v1 overlay */
.about-v4 .about-image::after { display: none; } /* Override v1 border */

.about-v4 .about-text {
    padding-right: 0; /* Remove padding */
}

.about-v4 .about-text h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: var(--dark-text-v4);
}

.about-v4 .about-text p {
    margin-bottom: 1rem;
    font-size: 0.95rem;
    color: var(--medium-text-v4);
}

.about-v4 .about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1rem;
    margin-top: 2rem;
    background-color: var(--light-bg-v4);
    padding: 1.5rem;
    border-radius: var(--border-radius-base-v4);
    border: 1px solid var(--border-color-medium-v4);
}

.about-v4 .stat-item {
    text-align: center;
}

.about-v4 .stat-number {
    font-size: 2rem;
    font-weight: 700;
    color: var(--primary-dark-v4);
    margin-bottom: 0.25rem;
}

.about-v4 .stat-text {
    font-size: 0.8rem;
    color: var(--primary-color-v4);
    text-transform: uppercase;
    letter-spacing: 0.5px;
    font-weight: 500;
}

/* === V4 产品展示 === */
.products-v4 {
    background-color: var(--light-bg-v4);
}
.products-v4::before { display: none; } /* Override v1 pattern */

.products-v4 .product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 2rem;
}

.products-v4 .product-card {
    background: var(--white-v4);
    border-radius: var(--border-radius-lg-v4);
    overflow: hidden;
    box-shadow: var(--shadow-sm-v4);
    transition: var(--transition-v4);
    border: 1px solid var(--border-color-light-v4);
    height: 100%;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 1;
}

.products-v4 .product-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, transparent 50%, rgba(16, 185, 129, 0.05) 100%);
    z-index: -1;
    opacity: 0;
    transition: var(--transition-v4);
}

.products-v4 .product-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg-v4);
    border-color: var(--primary-light-v4);
}

.products-v4 .product-card:hover::before {
    opacity: 1;
}

.products-v4 .product-image {
    height: 220px;
    overflow: hidden;
    position: relative;
}

.products-v4 .product-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, rgba(0,0,0,0.1), transparent);
    z-index: 1;
}

.products-v4 .product-info {
    padding: 1.2rem;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.products-v4 .product-info h3 {
    font-size: 1.1rem;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--dark-text-v4);
}

.products-v4 .product-info p {
    color: var(--medium-text-v4);
    font-size: 0.9rem;
    margin-bottom: 1rem;
    flex-grow: 1;
}

.products-v4 .product-link {
    color: var(--primary-color-v4);
    font-weight: 500;
    font-size: 0.85rem;
}
.products-v4 .product-link:hover {
    color: var(--primary-dark-v4);
}
.products-v4 .product-link i {
     font-size: 0.75rem;
}

/* === V4 服务项目 === */
.services-v4 {
    background-color: var(--white-v4);
}
.services-v4::before { display: none; } /* Override v1 effect */

.services-v4 .services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.services-v4 .service-card {
    background: var(--white-v4);
    border-radius: var(--border-radius-lg-v4);
    padding: 2.5rem 2rem;
    text-align: center;
    box-shadow: var(--shadow-sm-v4);
    transition: var(--transition-v4);
    border: 1px solid var(--border-color-light-v4);
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.services-v4 .service-card::before {
    content: '';
    position: absolute;
    top: -10px;
    right: -10px;
    width: 70px;
    height: 70px;
    background-color: var(--medium-bg-v4);
    border-radius: 50%;
    opacity: 0.3;
    z-index: -1;
    transition: var(--transition-v4);
}

.services-v4 .service-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg-v4);
    border-color: var(--primary-color-v4);
}

.services-v4 .service-card:hover::before {
    transform: scale(2.5);
    opacity: 0.1;
}

.services-v4 .service-icon {
    width: 70px;
    height: 70px;
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.6rem;
    color: white;
    transition: var(--transition-v4);
    margin-bottom: 1.5rem;
    box-shadow: 0 5px 15px rgba(16, 185, 129, 0.2);
}

.services-v4 .service-card:hover .service-icon {
    transform: rotateY(360deg);
    box-shadow: 0 8px 20px rgba(16, 185, 129, 0.3);
}

.services-v4 .service-card h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    font-weight: 600;
    color: var(--dark-text-v4);
    position: relative;
    padding-bottom: 0.8rem;
}

.services-v4 .service-card h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 2px;
    background-color: var(--primary-color-v4);
    border-radius: 1px;
}

.services-v4 .service-card p {
    color: var(--medium-text-v4);
    font-size: 0.95rem;
    line-height: 1.7;
}

/* === V4 新闻动态 === */
.news-v4 {
    background-color: var(--light-bg-v4);
}

.news-v4 .news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.news-v4 .news-card {
    background-color: var(--white-v4);
    border-radius: var(--border-radius-lg-v4);
    overflow: hidden;
    box-shadow: var(--shadow-sm-v4);
    transition: var(--transition-v4);
    border: 1px solid var(--border-color-light-v4);
    height: 100%;
}

.news-v4 .news-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg-v4);
    border-color: var(--primary-light-v4);
}

.news-v4 .news-image {
    height: 200px;
    overflow: hidden;
    position: relative;
}

.news-v4 .news-image img {
    transition: transform 0.8s ease;
}

.news-v4 .news-card:hover .news-image img {
    transform: scale(1.1);
}

.news-v4 .news-image::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, rgba(0,0,0,0.2), transparent);
    z-index: 1;
}

.news-v4 .news-content {
    padding: 1.5rem;
}

.news-v4 .news-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.8rem;
    margin-bottom: 0.8rem;
    color: var(--light-text-v4);
}

.news-v4 .news-date {
    display: flex;
    align-items: center;
    gap: 0.3rem;
}

.news-v4 .news-category {
    background-color: var(--medium-bg-v4);
    color: var(--primary-dark-v4);
    padding: 3px 10px;
    font-weight: 500;
    border-radius: 4px;
}

.news-v4 .news-title {
    font-size: 1.15rem;
    font-weight: 600;
    margin-bottom: 0.8rem;
    line-height: 1.4;
}

.news-v4 .news-title a {
    color: var(--dark-text-v4);
    transition: var(--transition-v4);
}

.news-v4 .news-title a:hover {
    color: var(--primary-color-v4);
}

.news-v4 .news-excerpt {
    font-size: 0.9rem;
    color: var(--medium-text-v4);
    margin-bottom: 1rem;
    line-height: 1.6;
    display: -webkit-box;
    -webkit-line-clamp: 3;
    -webkit-box-orient: vertical;  
    overflow: hidden;
}

.news-v4 .news-readmore {
    color: var(--primary-color-v4);
    font-size: 0.85rem;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 0.3rem;
    position: relative;
    overflow: hidden;
}

.news-v4 .news-readmore i {
    transition: transform 0.3s ease;
}

.news-v4 .news-readmore:hover {
    color: var(--primary-dark-v4);
}

.news-v4 .news-readmore:hover i {
    transform: translateX(4px);
}

/* === V4 联系我们 === */
.contact-v4 {
    background-color: var(--white-v4);
    padding-bottom: 6rem;
}

.contact-v4 .contact-content {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr; /* Form slightly wider */
    gap: 3rem;
    align-items: flex-start; /* Align items top */
}

.contact-v4 .contact-form {
    background: var(--white-v4);
    border-radius: var(--border-radius-lg-v4);
    padding: 2.5rem;
    box-shadow: var(--shadow-lg-v4);
    border: 1px solid var(--border-color-light-v4);
    position: relative;
    z-index: 1;
    overflow: hidden;
}

.contact-v4 .contact-form::before {
    content: '';
    position: absolute;
    top: -10%;
    right: -10%;
    width: 200px;
    height: 200px;
    background: var(--medium-bg-v4);
    border-radius: 50%;
    z-index: -1;
    opacity: 0.5;
}

.contact-v4 .form-group {
    margin-bottom: 1.5rem;
    position: relative;
}

.contact-v4 .form-label {
    display: block;
    margin-bottom: 0.6rem;
    font-size: 0.9rem;
    font-weight: 500;
    color: var(--dark-text-v4);
}

.contact-v4 .form-group input,
.contact-v4 .form-group textarea {
    width: 100%;
    padding: 0.9rem 1rem;
    border: 1px solid var(--border-color-light-v4);
    border-radius: var(--border-radius-base-v4);
    font-family: inherit;
    font-size: 0.95rem;
    transition: var(--transition-v4);
    background-color: var(--white-v4);
    color: var(--dark-text-v4);
}

.contact-v4 .form-group input::placeholder,
.contact-v4 .form-group textarea::placeholder {
    color: var(--light-text-v4);
    opacity: 0.8;
}

.contact-v4 .form-group input:focus,
.contact-v4 .form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color-v4);
    box-shadow: 0 0 0 4px rgba(16, 185, 129, 0.1);
}

.contact-v4 .form-group textarea {
    height: 120px;
    resize: vertical;
}

.contact-v4 .contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.contact-v4 .info-item {
    background: var(--light-bg-v4);
    border-radius: var(--border-radius-lg-v4);
    padding: 1.8rem;
    box-shadow: var(--shadow-sm-v4);
    border: 1px solid var(--border-color-medium-v4);
    transition: var(--transition-v4);
    position: relative;
    overflow: hidden;
    z-index: 1;
}

.contact-v4 .info-item::before {
    content: '';
    position: absolute;
    bottom: -50%;
    right: -50%;
    width: 100px;
    height: 100px;
    background: var(--medium-bg-v4);
    border-radius: 50%;
    z-index: -1;
    opacity: 0.3;
    transition: var(--transition-v4);
}

.contact-v4 .info-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md-v4);
    border-color: var(--primary-color-v4);
}

.contact-v4 .info-item:hover::before {
    transform: scale(1.5);
}

.contact-v4 .info-icon {
    width: 55px;
    height: 55px;
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.3rem;
    color: white;
    margin-bottom: 1.2rem;
    box-shadow: 0 5px 15px rgba(16, 185, 129, 0.2);
}

.contact-v4 .info-item h3 {
    font-size: 1.1rem;
    margin-bottom: 0.8rem;
    color: var(--dark-text-v4);
}

.contact-v4 .info-item p {
    color: var(--medium-text-v4);
    margin-bottom: 0.5rem;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.contact-v4 .info-item p i {
    color: var(--primary-dark-v4);
    font-size: 0.9rem;
    width: 16px; /* Align icons */
    text-align: center;
}

/* V4 Form Alert Placeholder - Adjust if needed */
.form-alert-placeholder {
    margin-top: 1rem;
}

/* === V4 友情链接 === */
.friend-links-v4 {
    background-color: var(--medium-bg-v4);
    padding: 3rem 0; /* Reduced padding */
    border-top: 1px solid var(--border-color-medium-v4);
}

.friend-links-v4 .section-header {
    margin-bottom: 2.5rem;
}
.friend-links-v4 .section-header p {
    color: var(--medium-text-v4);
}

.friend-links-v4 .links-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem 1.5rem; /* Reduced gap */
    max-width: 900px;
    margin: 0 auto;
}

.friend-links-v4 .links-grid a {
    color: var(--medium-text-v4);
    font-size: 0.9rem;
    padding: 4px 12px;
    border-radius: var(--border-radius-base-v4);
    transition: var(--transition-v4);
    background-color: rgba(255, 255, 255, 0.6);
    border: 1px solid var(--border-color-medium-v4);
}

.friend-links-v4 .links-grid a:hover {
    color: var(--primary-dark-v4);
    background-color: var(--white-v4);
    border-color: var(--primary-dark-v4);
    box-shadow: var(--shadow-sm-v4);
    transform: translateY(-2px);
}

/* === V4 页脚 === */
.footer-v4 {
    background-color: var(--footer-bg-v4);
    color: var(--footer-text-v4);
    padding: 5rem 0 1.5rem;
    position: relative;
    overflow: hidden;
}

.footer-v4::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 90% 20%, rgba(10, 101, 70, 0.4) 0%, transparent 50%);
    z-index: 0;
}

.footer-v4::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at 10% 80%, rgba(10, 101, 70, 0.4) 0%, transparent 50%);
    z-index: 0;
}

.footer-v4 .footer-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr; /* Adjusted columns */
    gap: 2.5rem; /* Reduced gap */
    margin-bottom: 2.5rem;
    position: relative;
    z-index: 1;
}

.footer-v4 .footer-content h3 {
    font-size: 1.1rem;
    margin-bottom: 1rem;
    color: var(--white-v4);
    position: relative;
    padding-bottom: 0.5rem;
    font-weight: 600;
}

.footer-v4 .footer-content h3::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: 0;
    width: 30px;
    height: 2px;
    background: var(--primary-color-v4);
    border-radius: 1px;
}

.footer-v4 .footer-about p {
    color: var(--footer-text-v4);
    font-size: 0.9rem;
    line-height: 1.7;
    margin-bottom: 1rem;
    opacity: 0.9;
}

.footer-v4 .social-icons {
    display: flex;
    gap: 0.8rem; /* Reduced gap */
    margin-top: 1rem;
}

.footer-v4 .social-icons a {
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.07);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--footer-text-v4);
    transition: var(--transition-v4);
    font-size: 0.95rem;
    position: relative;
    overflow: hidden;
}

.footer-v4 .social-icons a::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    opacity: 0;
    transition: var(--transition-v4);
    z-index: -1;
}

.footer-v4 .social-icons a:hover {
    color: var(--white-v4);
    transform: translateY(-5px);
}

.footer-v4 .social-icons a:hover::before {
    opacity: 1;
}

.footer-v4 .footer-links ul li {
    margin-bottom: 0.6rem; /* Reduced gap */
}

.footer-v4 .footer-links a {
    color: var(--footer-text-v4);
    transition: var(--transition-v4);
    display: inline-flex;
    align-items: center;
    font-size: 0.9rem;
    opacity: 0.9;
}

.footer-v4 .footer-links a i {
    margin-right: 0.4rem;
    font-size: 0.7rem;
    opacity: 0.7;
}

.footer-v4 .footer-links a:hover {
    color: var(--footer-link-hover-v4);
    opacity: 1;
    transform: translateX(4px);
}

.footer-v4 .footer-contact p {
    color: var(--footer-text-v4);
    margin-bottom: 0.7rem; /* Reduced gap */
    display: flex;
    align-items: flex-start; /* Align icon top */
    gap: 0.6rem;
    font-size: 0.9rem;
    opacity: 0.9;
}

.footer-v4 .footer-contact i {
    color: var(--primary-light-v4);
    margin-top: 0.2em;
    width: 16px; /* Align icons */
    text-align: center;
    flex-shrink: 0;
}

.footer-v4 .footer-bottom {
    border-top: 1px solid rgba(167, 243, 208, 0.2); /* Lighter border */
    padding-top: 1.5rem;
    text-align: center;
    color: #9ca3af; /* Gray 400 */
    font-size: 0.85rem;
}

.footer-v4 .footer-bottom a {
    color: var(--primary-light-v4);
    font-weight: 500;
}

/* === V4 回到顶部按钮 (Using V1 class name from JS) === */
.scroll-top-btn { /* Style matching the class added by script_v4.js */
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 45px;
    height: 45px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color-v4), var(--primary-dark-v4));
    color: white;
    border: none;
    font-size: 1.1rem;
    display: flex; /* Use flex added by JS */
    align-items: center;
    justify-content: center;
    cursor: pointer;
    z-index: 99;
    opacity: 0;
    visibility: hidden;
    transform: translateY(15px) scale(0.9);
    transition: all 0.3s ease-out;
    box-shadow: var(--shadow-md-v4);
}

.scroll-top-btn.visible { /* Style matching the class added by script_v4.js */
    opacity: 1;
    visibility: visible;
    transform: translateY(0) scale(1);
}

.scroll-top-btn:hover {
    transform: translateY(-3px) scale(1.05);
    box-shadow: var(--shadow-lg-v4);
}

/* === V4 响应式调整 (继承 V1 并修改) === */
@media (max-width: 992px) {
    .header-v4 .nav-links { display: none; }
    .header-v4 .mobile-menu { display: block; }
    .about-v4 .about-content {
        grid-template-columns: 1fr;
    }
    .about-v4 .about-text {
        order: -1; /* Text first */
    }
    .contact-v4 .contact-content {
        grid-template-columns: 1fr;
    }
     .footer-v4 .footer-content {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }
}

@media (max-width: 768px) {
     /* Inherit mobile nav styles from V1 */
    .nav-links { 
        position: fixed;
        top: 0;
        right: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        flex-direction: column;
        align-items: flex-start; /* Align items left */
        justify-content: flex-start; /* Align top */
        background: var(--white-v4);
        padding: 5rem 1.5rem 2rem; /* Adjust padding */
        box-shadow: -5px 0 20px rgba(0, 0, 0, 0.1);
        transition: right 0.4s ease;
        z-index: 1001;
        gap: 0; /* Reset gap */
    }
    .nav-links.active {
        right: 0;
    }
    .nav-links li {
        margin: 0;
        width: 100%;
    }
    .nav-links a {
        display: block; /* Make links full width */
        padding: 0.8rem 1rem; /* Add padding */
        font-size: 1rem;
        color: var(--dark-text-v4);
        font-weight: 500;
        border-bottom: 1px solid var(--border-color-light-v4);
    }
    .nav-links a i {
        display: inline-block; /* Show icons on mobile */
        margin-right: 0.8rem;
        width: 20px; 
        text-align: center;
        color: var(--primary-color-v4);
    }
    .nav-links a.active {
        color: var(--primary-color-v4);
        background-color: var(--light-bg-v4);
    }
    .nav-links a::after { display: none; }

    .overlay { /* Re-use V1 overlay */
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background: rgba(0, 0, 0, 0.5);
        z-index: 1000;
        opacity: 0;
        visibility: hidden;
        transition: all 0.3s ease;
    }
    .overlay.active {
        opacity: 1;
        visibility: visible;
    }
    
    .hero-v4 .hero-content h1 {
        font-size: 2.5rem;
    }
     .section-header h2 {
        font-size: 2rem;
    }
     .services-v4 .service-card {
         flex-direction: column; /* Stack icon and text */
         align-items: center; /* Center items */
         text-align: center;
     }
     .services-v4 .service-icon {
         margin-bottom: 1rem;
     }
}

@media (max-width: 576px) {
    section {
        padding: 3.5rem 0;
    }
    .container {
        padding: 0 1rem;
    }
    .hero-v4 .hero-content h1 {
        font-size: 2.1rem;
    }
    .hero-v4 .hero-content p {
        font-size: 1rem;
    }
    .hero-v4 .hero-buttons {
        flex-direction: column;
        gap: 0.8rem;
    }
    .hero-v4 .hero-buttons .btn {
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }
     .about-v4 .about-stats {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        padding: 1rem;
    }
     .footer-v4 .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }
     .footer-v4 .footer-about .social-icons {
         justify-content: center;
     }
     .footer-v4 .footer-links ul {
         padding-left: 0;
     }
      .footer-v4 .footer-contact p {
         justify-content: center;
     }
     .footer-v4 .footer-bottom {
         font-size: 0.8rem;
     }
}

/* 更新动画效果 */
.fade-up {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.6s ease-out, transform 0.6s ease-out;
}

.fade-up.fade-in {
    opacity: 1;
    transform: translateY(0);
}

/* 让动画序列化显示 */
.fade-up:nth-child(2) { transition-delay: 0.1s; }
.fade-up:nth-child(3) { transition-delay: 0.2s; }
.fade-up:nth-child(4) { transition-delay: 0.3s; }
.fade-up:nth-child(5) { transition-delay: 0.4s; }
.fade-up:nth-child(6) { transition-delay: 0.5s; }

/* 为区块添加波浪分隔符 */
.wave-divider {
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    overflow: hidden;
    line-height: 0;
    z-index: 1;
}

.wave-divider svg {
    position: relative;
    display: block;
    width: calc(100% + 1.3px);
    height: 90px;
}

.wave-divider .shape-fill {
    fill: var(--white-v4);
}

.light-section .wave-divider .shape-fill {
    fill: var(--light-bg-v4);
}

/* 自定义滚动条 */
::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: var(--light-bg-v4);
}

::-webkit-scrollbar-thumb {
    background: var(--primary-color-v4);
    border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--primary-dark-v4);
}

/* === V4 添加响应式调整 === */
@media (max-width: 576px) {
    section {
        padding: 3.5rem 0;
    }
    .container {
        padding: 0 1rem;
    }
    .hero-v4 .hero-content h1 {
        font-size: 2.1rem;
    }
    .hero-v4 .hero-content p {
        font-size: 1rem;
    }
    .hero-v4 .hero-buttons {
        flex-direction: column;
        gap: 0.8rem;
    }
    .hero-v4 .hero-buttons .btn {
        width: 100%;
        max-width: 300px;
        margin: 0 auto;
    }
     .about-v4 .about-stats {
        grid-template-columns: 1fr;
        gap: 1.5rem;
        padding: 1rem;
    }
     .footer-v4 .footer-content {
        grid-template-columns: 1fr;
        gap: 2rem;
        text-align: center;
    }
     .footer-v4 .footer-about .social-icons {
         justify-content: center;
     }
     .footer-v4 .footer-links ul {
         padding-left: 0;
     }
      .footer-v4 .footer-contact p {
         justify-content: center;
     }
     .footer-v4 .footer-bottom {
         font-size: 0.8rem;
     }
}