/* =========================================
   阿B落地页 - 终极转化版 CSS 架构
   更新：全局动效增强、响应式重构、转化引导优化
========================================= */

:root {
    /* 主题色系 */
    --primary-color: #0066ff;
    --primary-dark: #0052cc;
    --primary-light: #e6f0ff;
    --primary-gradient: linear-gradient(135deg, #0066ff 0%, #0044ff 100%);
    
    /* 辅助色系 (成功/警告) */
    --success-color: #10b981;
    --success-gradient: linear-gradient(135deg, #10b981 0%, #059669 100%);
    --accent-gradient: linear-gradient(135deg, #ff416c 0%, #ff4b2b 100%);
    
    /* 中性色与背景 */
    --bg-body: #f8fafc;
    --bg-card: #ffffff;
    --bg-dark: #0f172a;
    
    /* 文本色系 */
    --text-main: #0f172a;
    --text-muted: #64748b;
    --text-light: #f8fafc;
    
    /* 阴影与边框 */
    --shadow-sm: 0 2px 4px rgba(0,0,0,0.02);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -1px rgba(0,0,0,0.03);
    --shadow-hover: 0 20px 25px -5px rgba(0, 102, 255, 0.1), 0 10px 10px -5px rgba(0, 102, 255, 0.04);
    --shadow-glow: 0 0 20px rgba(16, 185, 129, 0.4);
    --border-light: rgba(226, 232, 240, 0.8);
    
    /* 动画曲线 */
    --easing-smooth: cubic-bezier(0.25, 0.8, 0.25, 1);
}

/* --- 全局重置与基础 --- */
*, *::before, *::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--bg-body);
    color: var(--text-main);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    line-height: 1.5;
}

/* =========================================
   1. 头部与导航 (Header & Nav)
========================================= */
.top-nav {
    position: absolute;
    top: 30px;
    right: 5%;
    display: flex;
    gap: 30px;
    z-index: 100;
    background: rgba(15, 23, 42, 0.4);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 10px 25px;
    border-radius: 50px;
    border: 1px solid rgba(255,255,255,0.05);
}

.top-nav a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s var(--easing-smooth);
    position: relative;
    padding: 4px 0;
}

.top-nav a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: width 0.3s var(--easing-smooth);
}

.top-nav a:hover, .top-nav a.active {
    color: #ffffff;
}

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

header {
    background: var(--bg-dark);
    background-image: radial-gradient(#1e293b 1px, transparent 1px);
    background-size: 24px 24px;
    color: white;
    padding: 100px 20px 80px;
    text-align: center;
    position: relative;
    overflow: hidden;
}

header::before {
    content: '';
    position: absolute;
    top: -50%;
    left: 50%;
    transform: translateX(-50%);
    width: 100%;
    height: 100%;
    background: radial-gradient(circle at center, rgba(0, 102, 255, 0.15) 0%, transparent 60%);
    pointer-events: none;
}

h1 {
    margin: 0 0 16px 0;
    font-size: 36px;
    font-weight: 800;
    letter-spacing: -0.5px;
    text-shadow: 0 2px 10px rgba(0,0,0,0.2);
    animation: slideDown 0.6s var(--easing-smooth) backwards;
}

.subtitle {
    color: #94a3b8;
    font-size: 16px;
    margin: 0 auto 40px;
    max-width: 650px;
    line-height: 1.7;
    animation: slideDown 0.6s var(--easing-smooth) 0.1s backwards;
}

/* 标签云 (拟态玻璃效果) */
.tags-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 12px;
    max-width: 900px;
    margin: 0 auto;
    animation: fadeIn 0.8s var(--easing-smooth) 0.2s backwards;
}

.tag {
    background: rgba(255, 255, 255, 0.08);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    color: #e2e8f0;
    padding: 8px 18px;
    border-radius: 50px;
    font-size: 13px;
    font-weight: 500;
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: all 0.3s var(--easing-smooth);
    display: flex;
    align-items: center;
    gap: 6px;
    cursor: default;
}

.tag:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-2px);
    border-color: rgba(255, 255, 255, 0.3);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

/* =========================================
   2. 核心布局与通用卡片
========================================= */
.container {
    max-width: 1200px;
    margin: -50px auto 40px;
    padding: 0 20px;
    position: relative;
    z-index: 10;
    padding-bottom: 80px;
}

.grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 30px;
}

/* 按钮基类 */
.btn {
    flex: 1;
    padding: 14px 0;
    text-align: center;
    border-radius: 10px;
    font-size: 14px;
    font-weight: 700;
    text-decoration: none;
    cursor: pointer;
    transition: all 0.3s var(--easing-smooth);
    border: none;
    display: block;
}

.btn-preview {
    background-color: #f1f5f9;
    color: var(--text-muted);
    border: 1px solid #e2e8f0;
}

.btn-preview:hover {
    background-color: #e2e8f0;
    color: var(--text-main);
    transform: translateY(-2px);
}

.btn-buy {
    background: var(--primary-gradient);
    color: #fff;
    box-shadow: 0 4px 12px rgba(0, 102, 255, 0.3);
}

.btn-buy:hover {
    box-shadow: 0 8px 20px rgba(0, 102, 255, 0.4);
    transform: translateY(-2px);
}

/* =========================================
   3. 首页 (Index) 专属组件
========================================= */
.card {
    background: var(--bg-card);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
    transition: all 0.4s var(--easing-smooth);
    display: flex;
    flex-direction: column;
    will-change: transform;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
    border-color: transparent;
}

.card-img-wrapper {
    position: relative;
    padding-top: 60%;
    background-color: #f8fafc;
    cursor: zoom-in;
    overflow: hidden;
}

.card-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: transform 0.6s var(--easing-smooth);
}

.card-img-wrapper:hover .card-img {
    transform: scale(1.06);
}

.zoom-icon {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%) scale(0.5);
    background: rgba(15, 23, 42, 0.7);
    backdrop-filter: blur(4px);
    color: white;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    transition: all 0.3s var(--easing-smooth);
}

.card-img-wrapper:hover .zoom-icon {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1);
}

.card-body {
    padding: 24px;
    flex-grow: 1;
    display: flex;
    flex-direction: column;
}

.card-meta {
    font-size: 12px;
    color: var(--primary-color);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
}

.card-title {
    font-size: 18px;
    font-weight: 700;
    margin: 0 0 10px 0;
}

.card-desc {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 24px;
    line-height: 1.6;
    flex-grow: 1;
}

.btn-group {
    display: flex;
    gap: 12px;
    margin-top: auto;
}

/* =========================================
   4. 服务报价页 (Pricing) 专属组件
========================================= */
.pricing-container {
    max-width: 1100px;
}

.pricing-section-title {
    font-size: 26px;
    font-weight: 800;
    margin: 60px 0 30px;
    display: flex;
    align-items: baseline;
    gap: 12px;
    letter-spacing: -0.5px;
}

.pricing-section-title span {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-muted);
    letter-spacing: normal;
}

.pricing-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 30px;
}

.pricing-grid.three-cols {
    grid-template-columns: repeat(3, 1fr);
}

/* 卡片允许溢出（为了显示右上角徽标） */
.pricing-card {
    background: var(--bg-card);
    border-radius: 20px;
    padding: 35px 30px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
    position: relative;
    display: flex;
    flex-direction: column;
    transition: all 0.4s var(--easing-smooth);
    overflow: visible; 
}

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

/* 主推卡片发光边框 */
.pricing-card.recommended {
    border: 2px solid var(--primary-color);
    box-shadow: 0 15px 35px rgba(0, 102, 255, 0.12);
    transform: scale(1.02);
    z-index: 2;
}

.pricing-card.recommended:hover {
    transform: scale(1.02) translateY(-5px);
    box-shadow: 0 20px 40px rgba(0, 102, 255, 0.2);
}

/* 徽标动画 */
.badge {
    position: absolute;
    top: -15px;
    right: 20px;
    background: var(--accent-gradient);
    color: white;
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 13px;
    font-weight: 800;
    box-shadow: 0 4px 12px rgba(255, 75, 43, 0.3);
    z-index: 10;
    animation: float 3s ease-in-out infinite;
}

.card-header {
    text-align: center;
    margin-bottom: 25px;
    padding-bottom: 25px;
    border-bottom: 1px solid #f1f5f9;
}

.card-header h3 {
    margin: 0 0 15px 0;
    font-size: 18px;
    color: var(--text-muted);
    font-weight: 600;
}

.price {
    font-size: 42px;
    font-weight: 900;
    color: var(--text-main);
    line-height: 1;
}

.price span {
    font-size: 16px;
    font-weight: 500;
    color: var(--text-muted);
    margin-left: 4px;
}

.features-list {
    list-style: none;
    padding: 0;
    margin: 0 0 30px 0;
    flex-grow: 1;
}

.features-list li {
    font-size: 14px;
    color: var(--text-main);
    margin-bottom: 16px;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    line-height: 1.6;
}

.features-list li.note {
    color: var(--text-muted);
    font-size: 13px;
    background: var(--bg-body);
    padding: 12px 16px;
    border-radius: 8px;
    margin-top: 24px;
}

.features-list svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: var(--primary-color);
    stroke-width: 2.5;
    flex-shrink: 0;
    margin-top: 2px;
}

.features-list li.note svg {
    stroke: #94a3b8;
}

.section-divider {
    border: 0;
    height: 1px;
    background: linear-gradient(to right, transparent, #e2e8f0, transparent);
    margin: 60px 0;
}

.simple-card {
    padding: 30px;
    justify-content: center;
}

/* FAQ 模块 */
.faq-section {
    margin-top: 60px;
    background: var(--bg-card);
    border-radius: 20px;
    padding: 50px;
    border: 1px solid var(--border-light);
    box-shadow: var(--shadow-md);
}

.faq-title {
    font-size: 22px;
    font-weight: 800;
    margin-bottom: 40px;
    text-align: center;
}

.faq-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.faq-item h4 {
    margin: 0 0 12px 0;
    font-size: 16px;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 8px;
}

.faq-item h4::before {
    content: '';
    display: block;
    width: 6px;
    height: 6px;
    background: var(--primary-color);
    border-radius: 50%;
}

.faq-item p {
    margin: 0;
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.7;
}

/* =========================================
   5. 防封客服说明页 (CS Guide) 专属组件
========================================= */
.cs-features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
    margin-top: 20px;
}

.feature-box {
    background: var(--bg-card);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
    transition: all 0.4s var(--easing-smooth);
}

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

.feature-icon {
    font-size: 44px;
    margin-bottom: 24px;
    background: var(--primary-light);
    width: 90px;
    height: 90px;
    line-height: 90px;
    border-radius: 50%;
    margin-left: auto;
    margin-right: auto;
    transition: transform 0.3s ease;
}

.feature-box:hover .feature-icon {
    transform: scale(1.1) rotate(5deg);
}

/* VS 对比区 */
.comparison-container {
    display: flex;
    align-items: stretch;
    justify-content: center;
    gap: 24px;
    margin: 40px auto;
    position: relative;
    max-width: 1050px;
}

.compare-card {
    flex: 1;
    background: var(--bg-card);
    border-radius: 20px;
    padding: 45px 40px;
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border-light);
}

.compare-card.bad {
    background: #fcfcfd;
    border-top: 4px solid #94a3b8;
    opacity: 0.9;
}

.compare-card.good {
    border: 2px solid var(--primary-color);
    border-top: 4px solid var(--primary-color);
    box-shadow: 0 20px 40px rgba(0, 102, 255, 0.15);
    position: relative;
    z-index: 2;
    transform: scale(1.03);
}

.vs-circle {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 54px;
    height: 54px;
    background: var(--bg-dark);
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 900;
    font-size: 16px;
    z-index: 3;
    border: 6px solid var(--bg-body);
    box-shadow: 0 4px 10px rgba(0,0,0,0.1);
}

.compare-header {
    text-align: center;
    margin-bottom: 35px;
    padding-bottom: 25px;
    border-bottom: 1px solid #f1f5f9;
}

.compare-header h4 {
    margin: 0 0 10px 0;
    font-size: 22px;
    font-weight: 800;
}

.compare-card.bad h4 { color: #475569; }
.compare-card.good h4 { color: var(--primary-color); }

.compare-subtitle {
    font-size: 14px;
    color: var(--text-muted);
}

.compare-list {
    list-style: none;
    padding: 0;
    margin: 0;
}

.compare-list li {
    padding: 16px 0;
    border-bottom: 1px dashed #e2e8f0;
    font-size: 15px;
    color: var(--text-main);
    display: flex;
    align-items: flex-start;
    transition: background-color 0.2s ease;
}

.compare-list li:hover {
    background-color: #f8fafc;
    border-radius: 6px;
    padding-left: 8px;
    padding-right: 8px;
}

.compare-list li:last-child { border-bottom: none; }

.compare-list li span {
    color: var(--text-muted);
    min-width: 80px;
    margin-right: 8px;
    font-weight: 500;
}

.compare-list li.cross::before {
    content: '✖';
    color: #ef4444;
    margin-right: 12px;
    font-size: 12px;
    margin-top: 3px;
}

.compare-list li.check::before {
    content: '✔';
    color: var(--success-color);
    margin-right: 12px;
    font-size: 16px;
    font-weight: 900;
    margin-top: 0;
}

.compare-action {
    margin-top: 40px;
    text-align: center;
}

/* 底部极速演示横幅 */
.cs-test-banner {
    background: linear-gradient(135deg, #1e293b 0%, #0f172a 100%);
    border-radius: 20px;
    padding: 50px 40px;
    text-align: center;
    color: white;
    margin-top: 70px;
    box-shadow: 0 20px 40px rgba(15, 23, 42, 0.4);
    position: relative;
    overflow: hidden;
}

.cs-test-banner::after {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 50%;
    height: 100%;
    background: linear-gradient(to right, transparent, rgba(255,255,255,0.05), transparent);
    animation: shine 3s infinite;
}

.cs-test-banner h3 {
    margin: 0 0 16px 0;
    font-size: 26px;
    font-weight: 800;
}

.cs-test-banner p {
    margin: 0 0 10px 0;
    font-size: 16px;
    color: #cbd5e1;
}

.btn-demo-large {
    display: inline-block;
    background: var(--success-gradient);
    color: white;
    padding: 18px 45px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 800;
    font-size: 18px;
    margin-top: 30px;
    transition: all 0.3s var(--easing-smooth);
    box-shadow: 0 10px 25px rgba(16, 185, 129, 0.4);
    border: 2px solid rgba(255,255,255,0.15);
    animation: pulse-glow 2s infinite;
}

.btn-demo-large:hover {
    transform: translateY(-4px) scale(1.02);
    box-shadow: 0 15px 35px rgba(16, 185, 129, 0.5);
    animation: none; /* 悬停时停止脉冲 */
}

/* =========================================
   6. 悬浮交互与模态框 (Float & Lightbox)
========================================= */

/* 悬浮演示按钮 (带脉冲发光效果，吸引点击) */
.floating-demo-btn {
    position: fixed;
    bottom: 35px;
    left: 35px;
    z-index: 9990;
    background: var(--success-gradient);
    color: white;
    padding: 15px 30px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 800;
    font-size: 15px;
    display: flex;
    align-items: center;
    gap: 10px;
    border: 2px solid rgba(255,255,255,0.15);
    box-shadow: 0 10px 25px rgba(16, 185, 129, 0.4);
    transition: all 0.3s var(--easing-smooth);
    animation: pulse-glow 2s infinite;
}

.floating-demo-btn:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 35px rgba(16, 185, 129, 0.6);
    animation: none;
}

/* Lightbox 完美版 */
.lightbox {
    display: none;
    position: fixed;
    z-index: 10000;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(15, 23, 42, 0.85);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    justify-content: center;
    align-items: center;
    cursor: zoom-out;
    animation: fadeIn 0.25s var(--easing-smooth);
}

.lightbox img {
    max-width: 90%;
    max-height: 90vh;
    border-radius: 12px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    transform: scale(0.9);
    animation: zoomIn 0.3s var(--easing-smooth) forwards;
}

/* =========================================
   7. 动画库 (Keyframes)
========================================= */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideDown {
    from { opacity: 0; transform: translateY(-20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes zoomIn {
    to { transform: scale(1); }
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-6px); }
}

@keyframes shine {
    to { left: 150%; }
}

@keyframes pulse-glow {
    0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
    70% { box-shadow: 0 0 0 15px rgba(16, 185, 129, 0); }
    100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

/* =========================================
   8. 极致移动端适配 (Mobile Optimization)
========================================= */
@media (max-width: 900px) {
    /* 缩小头部字号和内边距 */
    header { padding: 80px 20px 50px; }
    h1 { font-size: 28px; }
    
    /* 导航栏变更为居中铺开或小间隔 */
    .top-nav { 
        top: 15px; 
        right: 50%; 
        transform: translateX(50%); 
        gap: 15px; 
        padding: 8px 20px;
        width: max-content;
    }
    
    /* 强制单列布局 */
    .pricing-grid, 
    .pricing-grid.three-cols, 
    .faq-grid, 
    .cs-features-grid { 
        grid-template-columns: 1fr; 
    }
    
    /* 价格和比对卡片重置缩放 */
    .pricing-card.recommended, 
    .compare-card.good { 
        transform: scale(1); 
    }
    .pricing-card.recommended:hover, 
    .compare-card.good:hover { 
        transform: translateY(-5px); 
    }
    
    /* VS对比图表变更为上下结构 */
    .comparison-container { 
        flex-direction: column; 
        gap: 40px; 
    }
    .vs-circle { 
        top: calc(50% - 20px); 
        transform: translate(-50%, -50%); 
        border-width: 4px;
    }
    
    /* 缩减卡片内边距 */
    .pricing-card, .compare-card, .faq-section { 
        padding: 25px; 
    }
    
    .pricing-section-title { 
        flex-direction: column; 
        gap: 5px; 
        text-align: center; 
        align-items: center; 
    }
    
    /* 悬浮按钮针对手机重新定位 */
    .floating-demo-btn { 
        bottom: 20px; 
        left: 20px; 
        padding: 12px 20px; 
        font-size: 14px;
    }
}