/* ==========================================================================
   影子机场官网 (yingzivpn.xyz) - 自然有机设计系统 (Natural Organic Style)
   字体：正楷体 (Kaiti, Noto Serif SC) + Outfit 现代英文字体
   设计主调：大地色系、温暖优雅、柔和有机椭圆卡片、微妙光影与浮动微动特效
   ========================================================================== */

:root {
    /* 色彩系统 - 自然大地色与有机柔和调性 */
    --bg-main: #f8f6f0;            /* 温暖柔和暖黄底色 */
    --bg-card: #ffffff;            /* 卡片纯白底色 */
    --bg-card-alt: #f3eee3;        /* 辅助浅褐有机色 */
    
    --text-primary: #3d2b1f;       /* 深咖啡/黑红自然正文色 */
    --text-secondary: #6e5d4f;     /* 柔和次要深褐文字 */
    --text-light: #9e8c7c;         /* 浅褐色辅助文字 */
    
    --brand-primary: #556b2f;      /* 自然橄榄绿/有机绿 */
    --brand-dark: #3a4b20;         /* 深橄榄绿悬停色 */
    --brand-accent: #8b5a2b;       /* 温暖大地红褐色 */
    --brand-soft: #e8efe0;         /* 淡绿色柔和衬底 */
    
    --border-color: #e5dccb;       /* 柔和自然边框 */
    --border-focus: #556b2f;
    
    /* 渐变色 */
    --grad-organic: linear-gradient(135deg, #f8f6f0 0%, #efe7d6 100%);
    --grad-button: linear-gradient(135deg, #556b2f 0%, #435523 100%);
    --grad-accent: linear-gradient(135deg, #8b5a2b 0%, #6e441f 100%);

    /* 字体族定义 - 严格使用正楷体与自然衬线风格 */
    --font-kaiti: "Kaiti", "楷体", "STKaiti", "KaiTi_GB2312", "Noto Serif SC", serif;
    --font-sans: "Outfit", -apple-system, BlinkMacSystemFont, sans-serif;

    /* 圆角 - 柔和有机造型 */
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 28px;
    --radius-organic: 40px 15px 40px 15px; /* 自然有机形态圆角 */
    --radius-pill: 9999px;

    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(61, 43, 31, 0.04);
    --shadow-md: 0 8px 24px rgba(61, 43, 31, 0.07);
    --shadow-lg: 0 16px 40px rgba(61, 43, 31, 0.12);
    --shadow-organic: 0 12px 30px rgba(85, 107, 47, 0.08);

    /* 动画 transition */
    --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-normal: 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

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

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

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    font-family: var(--font-kaiti);
    line-height: 1.8;
    overflow-x: hidden;
    position: relative;
    -webkit-font-smoothing: antialiased;
}

/* 动态背景修饰 */
.organic-bg-shapes {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1;
    pointer-events: none;
    overflow: hidden;
}

.shape {
    position: absolute;
    border-radius: 50%;
    filter: blur(70px);
    opacity: 0.45;
    animation: floatShape 20s ease-in-out infinite alternate;
}

.shape-1 {
    top: -10%;
    right: -5%;
    width: 550px;
    height: 550px;
    background: #e8efe0;
}

.shape-2 {
    top: 30%;
    left: -10%;
    width: 600px;
    height: 600px;
    background: #f3eee3;
}

.shape-3 {
    bottom: 10%;
    right: -10%;
    width: 500px;
    height: 500px;
    background: #e9e2d0;
}

.shape-4 {
    bottom: -10%;
    left: 20%;
    width: 450px;
    height: 450px;
    background: #e1ebd7;
}

@keyframes floatShape {
    0% { transform: translate(0, 0) scale(1); }
    50% { transform: translate(30px, -40px) scale(1.08); }
    100% { transform: translate(-20px, 30px) scale(0.95); }
}

/* 链接与按钮通用 */
a {
    color: var(--brand-primary);
    text-decoration: none;
    transition: color var(--transition-fast);
}

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

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    font-family: var(--font-kaiti);
    font-size: 1.05rem;
    font-weight: 600;
    border-radius: var(--radius-pill);
    cursor: pointer;
    transition: all var(--transition-normal);
    border: none;
    outline: none;
}

.btn-primary {
    background: var(--brand-primary);
    color: #ffffff;
    box-shadow: 0 4px 14px rgba(85, 107, 47, 0.25);
}

.btn-primary:hover {
    background: var(--brand-dark);
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(85, 107, 47, 0.35);
}

.btn-secondary {
    background: var(--bg-card-alt);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: var(--border-color);
    color: var(--text-primary);
    transform: translateY(-2px);
}

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

.btn-outline:hover {
    background: var(--brand-primary);
    color: #ffffff;
    transform: translateY(-2px);
}

.btn-large {
    padding: 16px 36px;
    font-size: 1.15rem;
}

.btn-sm {
    padding: 8px 18px;
    font-size: 0.95rem;
}

.btn-block {
    width: 100%;
}

/* 导航栏 Navbar */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(248, 246, 240, 0.88);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(229, 220, 203, 0.6);
    padding: 16px 0;
    transition: all var(--transition-fast);
}

.nav-container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-icon {
    font-size: 1.6rem;
}

.logo-text {
    font-family: var(--font-kaiti);
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: 1px;
}

.logo-tag {
    font-family: var(--font-sans);
    font-size: 0.8rem;
    background: var(--brand-soft);
    color: var(--brand-primary);
    padding: 2px 8px;
    border-radius: var(--radius-pill);
    font-weight: 600;
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
}

.nav-item {
    font-family: var(--font-kaiti);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--text-secondary);
    position: relative;
    padding: 4px 0;
}

.nav-item:hover, .nav-item.active {
    color: var(--brand-primary);
}

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

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

.nav-actions {
    display: flex;
    gap: 16px;
    align-items: center;
}

/* Hero 核心首屏 */
.hero-section {
    padding: 90px 24px 70px;
    text-align: center;
    position: relative;
}

.hero-container {
    max-width: 960px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 6px 18px;
    border-radius: var(--radius-pill);
    font-size: 0.95rem;
    color: var(--brand-primary);
    box-shadow: var(--shadow-sm);
    margin-bottom: 24px;
}

.hero-title {
    font-family: var(--font-kaiti);
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.25;
    color: var(--text-primary);
    margin-bottom: 24px;
    letter-spacing: 1px;
}

.highlight-text {
    color: var(--brand-primary);
    background: linear-gradient(180deg, transparent 60%, var(--brand-soft) 60%);
}

.hero-description {
    font-size: 1.25rem;
    color: var(--text-secondary);
    max-width: 760px;
    margin: 0 auto 40px;
    line-height: 1.9;
}

.hero-cta-group {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-bottom: 60px;
}

/* 首屏特征椭圆微动卡片 */
.hero-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 20px;
}

.stat-pill {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 24px 16px;
    border-radius: 60px 20px 60px 20px; /* 图1风格有机椭圆结构 */
    box-shadow: var(--shadow-md);
    transition: transform var(--transition-normal), box-shadow var(--transition-normal);
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-pill:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-organic);
    border-color: var(--brand-primary);
}

.stat-num {
    font-family: var(--font-sans);
    font-size: 2rem;
    font-weight: 700;
    color: var(--brand-primary);
    line-height: 1;
    margin-bottom: 8px;
}

.stat-label {
    font-size: 1rem;
    color: var(--text-secondary);
}

/* 通用 Section 规则 */
.section {
    padding: 80px 24px;
}

.section-container {
    max-width: 1240px;
    margin: 0 auto;
}

.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 50px;
}

.sub-title {
    font-family: var(--font-sans);
    font-size: 0.85rem;
    font-weight: 700;
    color: var(--brand-accent);
    letter-spacing: 2px;
    text-transform: uppercase;
    display: block;
    margin-bottom: 8px;
}

.section-title {
    font-family: var(--font-kaiti);
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.section-desc {
    font-size: 1.15rem;
    color: var(--text-secondary);
}

/* 核心优势 Features */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    padding: 36px 28px;
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--brand-primary);
}

.feature-icon {
    font-size: 2.5rem;
    margin-bottom: 20px;
    display: inline-block;
    padding: 12px;
    background: var(--bg-card-alt);
    border-radius: 50%;
}

.feature-card h3 {
    font-family: var(--font-kaiti);
    font-size: 1.4rem;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.feature-card p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.8;
}

/* 套餐方案 Pricing (参考图1/图2精致样式) */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    align-items: stretch;
}

.pricing-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 40px 32px;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    transition: all var(--transition-normal);
    position: relative;
}

.pricing-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
}

.pricing-card.featured {
    border: 2px solid var(--brand-primary);
    background: linear-gradient(180deg, #ffffff 0%, #f9faf7 100%);
}

.popular-badge {
    position: absolute;
    top: -16px;
    right: 30px;
    background: var(--brand-primary);
    color: #ffffff;
    font-size: 0.85rem;
    font-weight: 600;
    padding: 4px 16px;
    border-radius: var(--radius-pill);
    box-shadow: 0 4px 10px rgba(85, 107, 47, 0.3);
}

.pricing-header h3 {
    font-family: var(--font-kaiti);
    font-size: 1.5rem;
    color: var(--text-primary);
    margin-bottom: 16px;
}

.price-box {
    display: flex;
    align-items: baseline;
    margin-bottom: 8px;
}

.price-box .currency {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--brand-primary);
    margin-right: 2px;
}

.price-box .amount {
    font-family: var(--font-sans);
    font-size: 3rem;
    font-weight: 700;
    color: var(--text-primary);
    line-height: 1;
}

.price-box .period {
    font-size: 1rem;
    color: var(--text-light);
    margin-left: 4px;
}

.pricing-desc {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 28px;
    padding-bottom: 20px;
    border-bottom: 1px dashed var(--border-color);
}

.pricing-features {
    list-style: none;
    margin-bottom: 36px;
}

.pricing-features li {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 14px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.pricing-features .check {
    color: var(--brand-primary);
    font-weight: bold;
}

/* 文章知识库 Articles Section */
.articles-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.article-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    padding: 30px;
    box-shadow: var(--shadow-sm);
    transition: all var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.article-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-md);
    border-color: var(--brand-primary);
}

.article-tag {
    align-self: flex-start;
    background: var(--bg-card-alt);
    color: var(--brand-accent);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 4px 12px;
    border-radius: var(--radius-pill);
    margin-bottom: 16px;
}

.article-title {
    font-family: var(--font-kaiti);
    font-size: 1.35rem;
    font-weight: 700;
    line-height: 1.5;
    margin-bottom: 12px;
}

.article-title a {
    color: var(--text-primary);
}

.article-title a:hover {
    color: var(--brand-primary);
}

.article-summary {
    font-size: 1rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 20px;
    flex-grow: 1;
}

.article-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.88rem;
    color: var(--text-light);
    border-top: 1px solid var(--bg-card-alt);
    padding-top: 14px;
}

/* FAQ 常见问题 */
.faq-accordion {
    max-width: 860px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.faq-item {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    overflow: hidden;
    transition: all var(--transition-fast);
}

.faq-question {
    padding: 24px 30px;
    font-family: var(--font-kaiti);
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-primary);
    cursor: pointer;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.faq-icon {
    font-size: 1.5rem;
    color: var(--brand-primary);
    transition: transform var(--transition-fast);
}

.faq-answer {
    padding: 0 30px 24px;
    color: var(--text-secondary);
    font-size: 1.05rem;
    line-height: 1.8;
}

.faq-item.active .faq-icon {
    transform: rotate(45deg);
}

/* 页脚 Footer */
.footer {
    background: #eed8c0;
    background: linear-gradient(180deg, #f3eee3 0%, #ea526 100%);
    background-color: #ede6d6;
    border-top: 1px solid var(--border-color);
    padding: 70px 24px 40px;
}

.footer-container {
    max-width: 1240px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 2fr 1fr 1fr 1.5fr;
    gap: 40px;
}

.brand-col .logo {
    margin-bottom: 16px;
}

.footer-desc {
    color: var(--text-secondary);
    font-size: 1rem;
    margin-bottom: 20px;
    line-height: 1.7;
}

.footer-col h4 {
    font-family: var(--font-kaiti);
    font-size: 1.25rem;
    color: var(--text-primary);
    margin-bottom: 20px;
}

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

.footer-col ul li {
    margin-bottom: 10px;
}

.footer-col ul li a {
    color: var(--text-secondary);
    font-size: 1rem;
}

.footer-col ul li a:hover {
    color: var(--brand-primary);
}

.footer-col p {
    color: var(--text-secondary);
    font-size: 0.95rem;
    margin-bottom: 8px;
}

/* 文章详情页专用样式 */
.article-page {
    padding: 60px 24px;
}

.article-container {
    max-width: 900px;
    margin: 0 auto;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 60px 50px;
    box-shadow: var(--shadow-md);
}

.article-header {
    text-align: center;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 30px;
    margin-bottom: 40px;
}

.article-header h1 {
    font-family: var(--font-kaiti);
    font-size: 2.4rem;
    line-height: 1.35;
    color: var(--text-primary);
    margin-bottom: 20px;
}

.article-header-meta {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 20px;
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.article-body {
    font-family: var(--font-kaiti);
    font-size: 1.15rem;
    line-height: 2;
    color: var(--text-primary);
}

.article-body h2 {
    font-size: 1.7rem;
    color: var(--brand-primary);
    margin: 40px 0 20px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--brand-soft);
}

.article-body h3 {
    font-size: 1.4rem;
    color: var(--text-primary);
    margin: 30px 0 15px;
}

.article-body p {
    margin-bottom: 20px;
    text-align: justify;
    text-indent: 2em;
}

.article-body ul, .article-body ol {
    margin: 0 0 24px 2em;
}

.article-body li {
    margin-bottom: 8px;
}

.article-cta-box {
    background: var(--bg-card-alt);
    border: 2px dashed var(--brand-primary);
    border-radius: var(--radius-md);
    padding: 30px;
    text-align: center;
    margin: 40px 0;
}

.article-cta-box h4 {
    font-size: 1.4rem;
    color: var(--text-primary);
    margin-bottom: 10px;
}

.article-cta-box p {
    text-indent: 0;
    text-align: center;
    margin-bottom: 20px;
}

/* 导航与全站响应式适配 */
@media (max-width: 1024px) {
    .features-grid, .pricing-grid, .articles-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .hero-stats {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-container {
        grid-template-columns: 1fr 1fr;
    }
}

@media (max-width: 768px) {
    .navbar .nav-links {
        display: none;
    }
    .hero-title {
        font-size: 2.4rem;
    }
    .features-grid, .pricing-grid, .articles-grid {
        grid-template-columns: 1fr;
    }
    .hero-stats {
        grid-template-columns: 1fr;
    }
    .footer-container {
        grid-template-columns: 1fr;
    }
    .article-container {
        padding: 30px 20px;
    }
    .article-body p {
        text-indent: 0;
    }
}