/* ==========================================================================
   400白菜导航网 - 现代农业生态供应链高端商业美学样式表
   文件名称: style.css
   设计规范: 极致SEO、响应式布局、平滑动效、留白艺术
   ========================================================================== */

/* --- 1. 基础重置与全局变量 --- */
:root {
    --color-primary: #1a5319;       /* 生态绿 - 核心品牌色 */
    --color-primary-light: #2e7d32; /* 浅绿 - 交互色 */
    --color-secondary: #f39c12;     /* 丰收黄 - 鲜明点缀 */
    --color-accent: #e8f5e9;        /* 嫩芽绿 - 背景缓冲 */
    --color-dark: #2c3e50;          /* 深墨色 - 文本阅读色 */
    --color-light: #ffffff;         /* 纯净白 - 呼吸留白 */
    --color-gray: #7f8c8d;          /* 辅助灰 - 次要信息 */
    --color-border: #eaeded;        /* 优雅线 - 分隔边界 */
    --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Microsoft YaHei", sans-serif;
    --transition-smooth: all 0.4s cubic-bezier(0.165, 0.84, 0.44, 1);
    --shadow-subtle: 0 4px 20px rgba(0, 0, 0, 0.05);
    --shadow-hover: 0 12px 30px rgba(26, 83, 25, 0.15);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
    color: var(--color-dark);
    font-family: var(--font-main);
    -webkit-font-smoothing: antialiased;
}

body {
    background-color: var(--color-light);
    line-height: 1.8;
    overflow-x: hidden;
}

/* --- 2. 极致排版与原子样式 --- */
h1, h2, h3, h4 {
    color: var(--color-dark);
    font-weight: 700;
    line-height: 1.3;
}

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

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

.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

.section-padding {
    padding: 100px 0;
}

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

/* 优雅的分隔线 */
.divider {
    width: 60px;
    height: 4px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    margin: 20px auto 40px;
    border-radius: 2px;
}

/* --- 3. 高端商业按钮与 CTA 动效 --- */
.btn-cta {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    font-weight: 600;
    font-size: 1rem;
    border-radius: 50px;
    transition: var(--transition-smooth);
    cursor: pointer;
    border: none;
    letter-spacing: 1px;
}

.btn-primary {
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    color: var(--color-light);
    box-shadow: 0 4px 15px rgba(26, 83, 25, 0.2);
}

.btn-primary:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-hover);
    background: linear-gradient(135deg, var(--color-primary-light), var(--color-primary));
}

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border: 2px solid var(--color-primary);
}

.btn-outline:hover {
    transform: scale(1.05);
    background: var(--color-primary);
    color: var(--color-light);
    box-shadow: var(--shadow-hover);
}

/* --- 4. Header 吸顶导航栏（含汉堡菜单逻辑） --- */
.header-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    box-shadow: 0 2px 20px rgba(0,0,0,0.03);
    z-index: 1000;
    display: flex;
    align-items: center;
}

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

/* 纯文本精美 Logo */
.logo-text {
    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-tag {
    font-size: 0.75rem;
    background: var(--color-secondary);
    color: var(--color-light);
    -webkit-text-fill-color: var(--color-light);
    padding: 2px 8px;
    border-radius: 4px;
    font-weight: 600;
    letter-spacing: 0px;
}

.nav-menu {
    display: flex;
    align-items: center;
    list-style: none;
    gap: 36px;
}

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

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

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

.nav-link:hover::after {
    width: 100%;
}

.nav-cta {
    font-size: 0.95rem;
    padding: 10px 24px;
    border-radius: 50px;
    background: var(--color-accent);
    color: var(--color-primary);
    font-weight: 600;
    border: 1px solid rgba(26, 83, 25, 0.1);
}

.nav-cta:hover {
    transform: scale(1.05);
    background: var(--color-primary);
    color: var(--color-light);
    box-shadow: 0 4px 15px rgba(26, 83, 25, 0.15);
}

/* 汉堡菜单核心触发器（隐藏） */
.menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 24px;
    height: 18px;
    cursor: pointer;
}

.menu-toggle span {
    width: 100%;
    height: 2px;
    background-color: var(--color-primary);
    transition: var(--transition-smooth);
    border-radius: 2px;
}

/* --- 5. Hero Section 英雄巨幕区 --- */
.hero-section {
    position: relative;
    padding-top: 180px;
    padding-bottom: 120px;
    background: linear-gradient(rgba(255,255,255,0.85), rgba(232,245,233,0.5)), url('/images/hero-bg.jpg') no-repeat center center / cover;
    display: flex;
    align-items: center;
    overflow: hidden;
}

.hero-content {
    max-width: 750px;
}

.hero-section h1 {
    font-size: 3.2rem;
    letter-spacing: -1px;
    margin-bottom: 24px;
    color: #113611;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--color-dark);
    margin-bottom: 40px;
    font-weight: 400;
    opacity: 0.9;
}

.hero-btns {
    display: flex;
    gap: 20px;
}

/* --- 6. Pain Points 痛点与情境区 --- */
.pain-section {
    background-color: var(--color-light);
}

.pain-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.pain-card {
    background-color: var(--color-light);
    border: 1px solid var(--color-border);
    padding: 40px 30px;
    border-radius: 12px;
    transition: var(--transition-smooth);
}

.pain-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-subtle);
    border-color: rgba(26, 83, 25, 0.15);
}

.pain-icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
    display: inline-block;
}

.pain-card h3 {
    font-size: 1.3rem;
    margin-bottom: 15px;
    color: var(--color-dark);
}

.pain-card p {
    color: var(--color-gray);
    font-size: 0.95rem;
}

/* --- 7. Solutions 核心产品与服务优势 --- */
.solutions-section {
    background-color: var(--color-accent);
}

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 50px;
}

.sol-card {
    background: var(--color-light);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-subtle);
    transition: var(--transition-smooth);
    border: 1px solid rgba(255,255,255,0.8);
}

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

.sol-img-wrapper {
    width: 100%;
    height: 220px;
    overflow: hidden;
    background-color: var(--color-accent);
}

.sol-img-wrapper img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition-smooth);
}

.sol-card:hover .sol-img-wrapper img {
    transform: scale(1.08);
}

.sol-content {
    padding: 35px 30px;
}

.sol-tag {
    color: var(--color-primary);
    font-weight: 700;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 10px;
    display: inline-block;
}

.sol-content h3 {
    font-size: 1.4rem;
    margin-bottom: 15px;
}

.sol-content p {
    color: var(--color-gray);
    font-size: 0.95rem;
    margin-bottom: 20px;
}

.sol-link {
    font-weight: 600;
    color: var(--color-primary);
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.sol-link:hover {
    color: var(--color-secondary);
}

/* --- 8. Social Proof 信任背书区 --- */
.proof-section {
    background-color: var(--color-light);
}

.proof-container {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 60px;
    align-items: center;
}

.proof-gallery {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.proof-img-box {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-subtle);
}

.proof-img-box img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.testimonial-slider {
    background: var(--color-accent);
    padding: 40px;
    border-radius: 16px;
    border-left: 5px solid var(--color-primary);
}

.testi-content {
    font-style: italic;
    font-size: 1.1rem;
    color: var(--color-dark);
    margin-bottom: 20px;
}

.testi-author {
    font-weight: 700;
    color: var(--color-primary);
}

.testi-author span {
    font-weight: 400;
    color: var(--color-gray);
    font-size: 0.9rem;
    margin-left: 10px;
}

/* --- 9. About Us 关于我们（本地化Local SEO强化） --- */
.about-section {
    background: linear-gradient(180deg, var(--color-light) 0%, var(--color-accent) 100%);
}

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text h2 {
    font-size: 2.2rem;
    margin-bottom: 20px;
}

.about-text p {
    color: var(--color-dark);
    margin-bottom: 20px;
    opacity: 0.85;
}

.info-list {
    margin-top: 30px;
    list-style: none;
}

.info-item {
    display: flex;
    align-items: flex-start;
    gap: 15px;
    margin-bottom: 20px;
}

.info-label {
    background: var(--color-primary);
    color: var(--color-light);
    padding: 4px 12px;
    border-radius: 4px;
    font-size: 0.85rem;
    font-weight: 600;
    white-space: nowrap;
}

.info-value {
    color: var(--color-dark);
    font-weight: 500;
}

/* --- 10. FAQ 常见问题区 --- */
.faq-section {
    background-color: var(--color-light);
}

.faq-max-width {
    max-width: 850px;
    margin: 40px auto 0;
}

/* 利用原生 details/summary 打造零 JS 高性能手风琴效果 */
details.faq-item {
    background-color: var(--color-light);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    margin-bottom: 16px;
    overflow: hidden;
    transition: var(--transition-smooth);
}

details.faq-item[open] {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-subtle);
}

summary.faq-title {
    padding: 20px 24px;
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--color-dark);
    cursor: pointer;
    list-style: none;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

/* 清除旧版 Safari 的默认三角符号 */
summary.faq-title::-webkit-details-marker {
    display: none;
}

summary.faq-title::after {
    content: '+';
    font-size: 1.5rem;
    color: var(--color-primary);
    transition: var(--transition-smooth);
}

details.faq-item[open] summary.faq-title::after {
    content: '−';
    transform: rotate(180deg);
}

.faq-content {
    padding: 0 24px 20px;
    color: var(--color-gray);
    font-size: 0.95rem;
    border-top: 1px solid transparent;
}

details.faq-item[open] .faq-content {
    border-top: 1px solid var(--color-border);
}

/* --- 11. Footer 页尾 --- */
.footer-section {
    background-color: #112211;
    color: rgba(255, 255, 255, 0.7);
    padding: 70px 0 30px;
    font-size: 0.9rem;
}

.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 40px;
    margin-bottom: 50px;
}

.footer-brand h4 {
    color: var(--color-light);
    font-size: 1.4rem;
    margin-bottom: 20px;
}

.footer-links h4, .footer-contact h4 {
    color: var(--color-light);
    font-size: 1.1rem;
    margin-bottom: 20px;
}

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

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

.footer-links a:hover {
    color: var(--color-secondary);
    padding-left: 4px;
}

.footer-contact p {
    margin-bottom: 12px;
}

.footer-contact a {
    color: var(--color-light);
    font-weight: 600;
}

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

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
}

.footer-beian a {
    color: rgba(255, 255, 255, 0.6);
    transition: var(--transition-smooth);
}

.footer-beian a:hover {
    color: var(--color-light);
}

/* ==========================================================================
   12. 响应式媒体查询 (Mobile-First 逻辑补全)
   ========================================================================== */

@media (max-width: 992px) {
    .pain-grid, .solutions-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .proof-container, .about-grid {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .hero-section h1 {
        font-size: 2.6rem;
    }
}

@media (max-width: 768px) {
    .section-padding {
        padding: 70px 0;
    }
    
    /* 汉堡菜单响应式激活 */
    .menu-toggle {
        display: flex;
        z-index: 1001;
    }
    
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 75%;
        height: 100vh;
        background-color: var(--color-light);
        box-shadow: -5px 0 30px rgba(0,0,0,0.1);
        flex-direction: column;
        justify-content: center;
        gap: 30px;
        transition: var(--transition-smooth);
        z-index: 1000;
    }
    
    /* 当隐藏的 checkbox 被勾选（在 HTML 阶段配置）或加 active 类时，菜单划出 */
    .menu-active .nav-menu {
        right: 0;
    }
    
    .pain-grid, .solutions-grid, .footer-grid {
        grid-template-columns: 1fr;
    }
    
    .hero-section {
        padding-top: 140px;
        padding-bottom: 80px;
        text-align: center;
    }
    
    .hero-btns {
        justify-content: center;
        flex-direction: column;
        gap: 15px;
    }
    
    .footer-bottom {
        flex-direction: column;
        text-align: center;
    }
}