/**
 * 绿叶生物官方网站样式
 * 主题：专业、科技、信赖
 * 主色：绿叶绿 #2E7D32
 */

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

:root {
    --primary: #2E7D32;
    --primary-dark: #1B5E20;
    --primary-light: #4CAF50;
    --accent: #FF6F00;
    --text-dark: #333333;
    --text-gray: #666666;
    --text-light: #999999;
    --bg-light: #F5F5F5;
    --bg-white: #FFFFFF;
    --border: #E0E0E0;
    --shadow: 0 2px 10px rgba(0,0,0,0.1);
    --shadow-hover: 0 8px 25px rgba(0,0,0,0.15);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-dark);
    background: var(--bg-white);
}

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

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 按钮样式 ===== */
.btn {
    display: inline-block;
    padding: 12px 25px;
    border-radius: 30px;
    font-size: 14px;
    font-weight: 700;
    cursor: pointer;
    transition: all 0.3s ease;
    border: 3px solid;
    white-space: nowrap;
}

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

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

.btn-outline {
    background: transparent;
    color: white;
    border-color: white;
}

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

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

.btn-white:hover {
    background: transparent;
    color: white;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: white;
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: all 0.3s ease;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 80px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo img {
    height: 50px;
}

.logo-text {
    font-size: 20px;
    font-weight: bold;
    color: var(--primary);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 30px;
}

.nav-menu a {
    font-size: 15px;
    color: var(--text-dark);
    font-weight: 500;
    position: relative;
}

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

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after,
.nav-menu a.active::after {
    width: 100%;
}

.hotline {
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--accent);
    font-weight: bold;
    font-size: 18px;
}

.mobile-menu-btn {
    display: none;
    font-size: 24px;
    cursor: pointer;
}

/* ===== Hero区域 ===== */
.hero {
    min-height: 100vh;
    background: linear-gradient(135deg, var(--primary-dark) 0%, var(--primary) 50%, var(--primary-light) 100%);
    display: flex;
    align-items: center;
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="40" r="3" fill="rgba(255,255,255,0.1)"/><circle cx="40" cy="80" r="2" fill="rgba(255,255,255,0.1)"/></svg>');
    opacity: 0.5;
}

.hero .container {
    position: relative;
    z-index: 1;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
    text-align: center;
}

.hero-badge {
    display: inline-block;
    background: rgba(255,255,255,0.2);
    padding: 8px 20px;
    border-radius: 20px;
    font-size: 14px;
    margin-bottom: 20px;
}

.hero h1 {
    font-size: 35px;
    line-height: 1.3;
    margin-bottom: 20px;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 20px;
    opacity: 0.95;
    margin-bottom: 30px;
    line-height: 1.8;
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 40px;
    margin: 40px 0;
}

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

.stat-number {
    font-size: 36px;
    font-weight: bold;
    display: block;
}

.stat-label {
    font-size: 14px;
    opacity: 0.9;
}

.hero-buttons {
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    justify-content: center;
}

@media (max-width: 768px) {
    .hero-buttons {
        flex-wrap: wrap;
        justify-content: center;
        gap: 10px;
    }
    .hero-buttons .btn:nth-child(1) {
        width: 100%;
    }
    .hero-buttons .btn:nth-child(n+2) {
        width: 48%;
    }
}

/* ===== 视频区域 ===== */
.video-section {
    padding: 80px 0;
    background: var(--bg-white);
}

.video-section:nth-child(even) {
    background: var(--bg-light);
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-tag {
    display: inline-block;
    background: rgba(46, 125, 50, 0.1);
    color: var(--primary);
    padding: 6px 16px;
    border-radius: 15px;
    font-size: 14px;
    margin-bottom: 15px;
}

.section-title {
    font-size: 36px;
    color: var(--text-dark);
    margin-bottom: 15px;
}

.section-subtitle {
    font-size: 18px;
    color: var(--text-gray);
}

.video-container {
    position: relative;
    max-width: 1000px;
    margin: 0 auto;
    overflow: hidden;
    box-shadow: var(--shadow-hover);
    border-radius: 12px;
    text-align: center;
}

.video-wrapper {
    width: 100%;
    margin: 0 auto;
}

.video-placeholder {
    aspect-ratio: 16/9;
    background: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
}

.play-btn {
    width: 80px;
    height: 80px;
    background: var(--primary);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.3s ease;
}

.play-btn:hover {
    transform: scale(1.1);
    background: var(--primary-light);
}

.play-btn::after {
    content: '';
    width: 0;
    height: 0;
    border-left: 25px solid white;
    border-top: 15px solid transparent;
    border-bottom: 15px solid transparent;
    margin-left: 8px;
}

.video-caption {
    padding: 20px;
    background: white;
    text-align: center;
}

.video-caption h3 {
    font-size: 20px;
    margin-bottom: 8px;
}

.video-caption p {
    color: var(--text-gray);
    font-size: 15px;
}

/* ===== 新闻区域 ===== */
.news-section {
    padding: 80px 0;
    background: var(--bg-white);
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 30px;
}

.news-card {
    background: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: all 0.3s ease;
}

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

.news-image {
    height: 200px;
    background: linear-gradient(135deg, var(--primary-light), var(--primary));
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 48px;
}

.news-content {
    padding: 25px;
}

.news-date {
    color: var(--text-light);
    font-size: 14px;
    margin-bottom: 10px;
}

.news-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 10px;
    line-height: 1.5;
}

.news-excerpt {
    color: var(--text-gray);
    font-size: 14px;
    line-height: 1.7;
}

/* ===== CTA区域 ===== */
.cta-section {
    padding: 100px 0;
    background: linear-gradient(135deg, var(--primary-dark), var(--primary));
    color: white;
    text-align: center;
}

.cta-section h2 {
    font-size: 36px;
    margin-bottom: 15px;
}

.cta-section p {
    font-size: 18px;
    opacity: 0.9;
    margin-bottom: 30px;
}

/* ===== 页脚 ===== */
.footer {
    background: #1a1a2e;
    color: white;
    padding: 60px 0 30px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    margin-bottom: 20px;
}

.footer-logo img {
    height: 40px;
}

.footer-desc {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
    line-height: 1.8;
}

.footer-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
}

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

.footer-links li {
    margin-bottom: 12px;
}

.footer-links a {
    color: rgba(255,255,255,0.7);
    font-size: 14px;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 30px;
    text-align: center;
    color: rgba(255,255,255,0.5);
    font-size: 14px;
}

/* ===== 动画效果 ===== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fadeInUp {
    animation: fadeInUp 0.8s ease forwards;
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .footer-grid {
        grid-template-columns: 1fr 1fr;
    }
}

/* 移动端修复：给body添加顶部间距，避免内容被固定导航栏遮挡 */
@media (max-width: 768px) {
    body {
        padding-top: 80px;
    }

    /* 移动端减少各区域间距 */
    .video-section,
    .news-section,
    .products-section,
    .hero {
        padding: 40px 0;
    }

    .news-section {
        padding-bottom: 0;
    }

    .cta-section {
        padding-top: 40px;
    }

    .section-header {
        margin-bottom: 30px;
    }

    .section-title {
        font-size: 24px;
    }

    .section-subtitle {
        font-size: 14px;
    }

    .navbar {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
    }
    .nav-menu {
        display: none;
        position: absolute;
        top: 80px;
        left: 0;
        right: 0;
        background: white;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hotline {
        display: none;
    }
    
    .hero h1 {
        font-size: 20px;
    }
    
    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .news-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* 新闻卡片链接样式 */
.news-card {
    display: block;
    text-decoration: none;
    color: inherit;
}