/* ============================================
   肽跃简栖官网 - 样式表
   品牌：肽跃生物科技（简栖）
   风格：温暖自然、清新治愈
   ============================================ */

/* CSS 变量 - 设计系统 */
:root {
    /* 色彩体系 */
    --color-primary: #4CAF50;
    --color-primary-light: #81C784;
    --color-primary-dark: #388E3C;
    --color-accent: #FF7043;
    --color-accent-hover: #F4511E;
    --color-text: #333333;
    --color-text-secondary: #666666;
    --color-text-light: #999999;
    --color-background: #F9FDF9;
    --color-white: #FFFFFF;
    --color-border: #E0E0E0;
    
    /* 字体 */
    --font-family-zh: "思源黑体", "Source Han Sans CN", "苹方", "PingFang SC", "Microsoft YaHei", sans-serif;
    --font-family-en: "Inter", "Helvetica", "Arial", sans-serif;
    
    /* 间距 */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    
    /* 断点 */
    --breakpoint-sm: 768px;
    --breakpoint-md: 992px;
    --breakpoint-lg: 1200px;
    
    /* 圆角 */
    --border-radius-sm: 4px;
    --border-radius-md: 8px;
    --border-radius-lg: 12px;
    --border-radius-xl: 16px;
    
    /* 阴影 */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 40px rgba(0, 0, 0, 0.15);
    
    /* 过渡 */
    --transition-fast: 0.15s ease;
    --transition-base: 0.3s ease;
    --transition-slow: 0.5s ease;
}

/* 基础重置 */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

body {
    font-family: var(--font-family-zh);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* 无障碍优化 - 跳过导航 */
.skip-link {
    position: absolute;
    top: -40px;
    left: 0;
    background: var(--color-primary);
    color: var(--color-white);
    padding: var(--spacing-sm) var(--spacing-md);
    z-index: 1000;
    transition: top var(--transition-fast);
}

.skip-link:focus {
    top: 0;
}

/* 容器 */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* 图片响应式 */
img,
picture {
    max-width: 100%;
    height: auto;
    display: block;
}

/* 链接基础样式 */
a {
    color: var(--color-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover,
a:focus {
    color: var(--color-primary-dark);
    text-decoration: underline;
}

/* 按钮样式 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 1rem;
    font-weight: 500;
    border: 2px solid transparent;
    border-radius: var(--border-radius-md);
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
}

.btn:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

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

.btn-primary:hover,
.btn-primary:focus {
    background-color: var(--color-accent-hover);
    border-color: var(--color-accent-hover);
    color: var(--color-white);
    text-decoration: none;
}

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

.btn-secondary:hover,
.btn-secondary:focus {
    background-color: var(--color-primary);
    color: var(--color-white);
    text-decoration: none;
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.125rem;
}

/* ============================================
   导航栏
   ============================================ */
.site-header {
    position: sticky;
    top: 0;
    z-index: 1000;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: var(--shadow-sm);
}

.navbar {
    padding: var(--spacing-sm) 0;
}

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

.navbar-brand {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--color-primary);
    text-decoration: none;
}

.navbar-brand:hover {
    color: var(--color-primary-dark);
    text-decoration: none;
}

/* Logo 图片样式 */
.navbar-brand img.brand-logo {
    height: 50px;
    width: auto;
    object-fit: contain;
    display: block;
}

.brand-icon {
    font-size: 1.75rem;
}

.navbar-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
}

.navbar-menu a {
    color: var(--color-text);
    font-weight: 500;
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.navbar-menu a:hover,
.navbar-menu a:focus,
.navbar-menu a[aria-current="page"] {
    color: var(--color-primary);
    background-color: rgba(76, 175, 80, 0.1);
    text-decoration: none;
}

    .navbar-brand img.brand-logo {
        height: 40px;
    }

.navbar-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.toggle-icon {
    display: block;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    position: relative;
    transition: background-color var(--transition-fast);
}

.toggle-icon::before,
.toggle-icon::after {
    content: "";
    position: absolute;
    width: 24px;
    height: 2px;
    background-color: var(--color-text);
    left: 0;
    transition: transform var(--transition-fast);
}

.toggle-icon::before {
    top: -8px;
}

.toggle-icon::after {
    top: 8px;
}

/* ============================================
   Hero Banner
   ============================================ */
.hero-banner {
    padding: var(--spacing-2xl) 0;
    background: linear-gradient(135deg, var(--color-background) 0%, rgba(129, 199, 132, 0.2) 100%);
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    align-items: center;
}

.hero-content {
    text-align: left;
}

.hero-title {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-primary);
    font-weight: 500;
}

.hero-slogan {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--color-text);
    line-height: 1.2;
}

.hero-description {
    font-size: 1.125rem;
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-lg);
}

.hero-image img {
    border-radius: var(--border-radius-xl);
    box-shadow: var(--shadow-lg);
}

/* ============================================
   Section 通用样式
   ============================================ */
section {
    padding: var(--spacing-2xl) 0;
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: var(--spacing-xl);
    color: var(--color-text);
}

.section-cta {
    text-align: center;
    margin-top: var(--spacing-xl);
}

/* ============================================
   核心优势区域
   ============================================ */
.features-section {
    background-color: var(--color-white);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-lg);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-lg);
    border-radius: var(--border-radius-lg);
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: var(--spacing-sm);
}

.feature-card h3 {
    font-size: 1.25rem;
    color: var(--color-primary);
    margin-bottom: var(--spacing-xs);
}

.feature-card p {
    color: var(--color-text-secondary);
    font-size: 0.95rem;
}

/* ============================================
   明星产品区域
   ============================================ */
.products-section {
    background-color: var(--color-background);
}

.products-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

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

.product-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

.product-image {
    position: relative;
    overflow: hidden;
}

.product-image img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

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

.product-info {
    padding: var(--spacing-lg);
}

.product-info h3 {
    font-size: 1.25rem;
    margin-bottom: var(--spacing-xs);
}

.product-info h3 a {
    color: var(--color-text);
    text-decoration: none;
}

.product-info h3 a:hover {
    color: var(--color-primary);
    text-decoration: none;
}

.product-desc {
    color: var(--color-text-secondary);
    margin-bottom: var(--spacing-md);
    font-size: 0.95rem;
}

/* ============================================
   品牌理念区域
   ============================================ */
.brand-section {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
    color: var(--color-white);
    text-align: center;
}

.brand-section .section-title {
    color: var(--color-white);
}

.brand-quote {
    font-size: 1.75rem;
    font-style: italic;
    margin-bottom: var(--spacing-md);
    padding: 0 var(--spacing-xl);
}

.brand-quote p {
    position: relative;
}

.brand-quote p::before,
.brand-quote p::after {
    content: """;
    font-size: 3rem;
    position: absolute;
    color: rgba(255, 255, 255, 0.5);
}

.brand-quote p::before {
    left: -1.5rem;
    top: -1rem;
}

.brand-quote p::after {
    right: -1.5rem;
    bottom: -1rem;
}

.brand-description {
    font-size: 1.125rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* ============================================
   最新资讯区域
   ============================================ */
.news-section {
    background-color: var(--color-white);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-lg);
}

.news-card {
    background-color: var(--color-background);
    border-radius: var(--border-radius-lg);
    overflow: hidden;
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.news-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.news-image {
    overflow: hidden;
}

.news-image img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    transition: transform var(--transition-slow);
}

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

.news-content {
    padding: var(--spacing-lg);
}

.news-category {
    display: inline-block;
    font-size: 0.875rem;
    color: var(--color-primary);
    background-color: rgba(76, 175, 80, 0.1);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: var(--border-radius-sm);
    margin-bottom: var(--spacing-xs);
}

.news-content h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-xs);
    line-height: 1.4;
}

.news-content h3 a {
    color: var(--color-text);
    text-decoration: none;
}

.news-content h3 a:hover {
    color: var(--color-primary);
    text-decoration: none;
}

.news-date {
    font-size: 0.875rem;
    color: var(--color-text-light);
}

/* ============================================
   页脚
   ============================================ */
.site-footer {
    background-color: var(--color-text);
    color: var(--color-white);
    padding: var(--spacing-2xl) 0 var(--spacing-lg);
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.footer-section h3 {
    font-size: 1.125rem;
    margin-bottom: var(--spacing-md);
    color: var(--color-primary-light);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.8);
    margin-bottom: var(--spacing-xs);
}

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

.footer-section ul li {
    margin-bottom: var(--spacing-xs);
}

.footer-section ul a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    transition: color var(--transition-fast);
}

.footer-section ul a:hover,
.footer-section ul a:focus {
    color: var(--color-primary-light);
    text-decoration: none;
}

.social-links {
    display: flex;
    gap: var(--spacing-sm);
}

.social-link {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    background-color: rgba(255, 255, 255, 0.1);
    border-radius: var(--border-radius-sm);
    color: var(--color-white);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.social-link:hover,
.social-link:focus {
    background-color: var(--color-primary);
    text-decoration: none;
}

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

.footer-bottom p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.875rem;
    margin-bottom: var(--spacing-xs);
}

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

/* 分页 */
.pagination-list {
    margin-top: var(--spacing-xl);
    text-align: center;
}

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: var(--spacing-xs);
    list-style: none;
}

.pagination li {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 40px;
    height: 40px;
    padding: 0 var(--spacing-sm);
    border: 1px solid var(--color-border);
    border-radius: var(--border-radius-sm);
    color: var(--color-text);
    text-decoration: none;
    transition: all var(--transition-fast);
}

.pagination li:hover,
.pagination li:focus {
    border-color: var(--color-primary);
    color: var(--color-primary);
    text-decoration: none;
}

.pagination li.active {
    background-color: var(--color-primary);
    border-color: var(--color-primary);
    color: var(--color-white);
}


/* ============================================
   响应式设计
   ============================================ */

/* 平板端 (768px - 1199px) */
@media (max-width: 1199px) {
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 991px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-content {
        text-align: center;
    }
    
    .hero-title {
        align-items: center;
    }
    
    .products-grid {
        grid-template-columns: 1fr;
    }
    
    .news-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* 移动端 (< 768px) */
@media (max-width: 767px) {
    :root {
        --spacing-xl: 2rem;
        --spacing-2xl: 3rem;
    }
    
    .navbar-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--color-white);
        flex-direction: column;
        padding: var(--spacing-md);
        box-shadow: var(--shadow-md);
    }
    
    .navbar-menu.active {
        display: flex;
    }
    
    .navbar-brand img.brand-logo {
        height: 40px;
    }

    .navbar-toggle {
        display: block;
    }
    
    .hero-slogan {
        font-size: 1.75rem;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .social-links {
        justify-content: center;
    }
    
    .section-title {
        font-size: 1.5rem;
    }
    
    .brand-quote {
        font-size: 1.25rem;
        padding: 0 var(--spacing-md);
    }
}

/* 打印样式 */
@media print {
    .site-header,
    .site-footer,
    .navbar-brand img.brand-logo {
        height: 40px;
    }

    .navbar-toggle {
        display: none;
    }
    
    body {
        background-color: var(--color-white);
    }
    
    .btn {
        display: none;
    }
}