/* --- 动态渐变背景 --- */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: -1; /* 确保在所有内容之下 */

    /* 
     * 创建一个巨大的径向渐变。
     * 中心是我们的品牌蓝，然后过渡到透明。
     * 'circle at var(--x) var(--y)' 定义了渐变中心的位置，我们将通过动画改变它。
    */
    background: radial-gradient(
        circle at var(--x) var(--y),
        rgba(0, 122, 255, 0.15), /* 核心颜色，透明度调低，使其柔和 */
        rgba(0, 122, 255, 0.1),
        transparent 40% /* 40%半径后完全透明 */
    );

    /* 调用动画 */
    animation: gradient-move 25s linear infinite;
}

/* 定义动画关键帧 */
@keyframes gradient-move {
    0% {
        --x: 0%;
        --y: 50%;
    }
    25% {
        --x: 100%;
        --y: 0%;
    }
    50% {
        --x: 100%;
        --y: 100%;
    }
    75% {
        --x: 0%;
        --y: 100%;
    }
    100% {
        --x: 0%;
        --y: 50%;
    }
}


/* --- 全局变量与重置 --- */
:root {
    --primary-blue: #007aff;
    --text-light: #f5f5f7;
    --text-dark: #1d1d1f;
    --text-secondary: #a1a1a6;
    --bg-black: #000000;
    --bg-dark-grey: #1a1a1c;
    --border-color: #424245;
    --font-main: "PingFang SC", "Helvetica Neue", "Arial", sans-serif;
}

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

html {
    scroll-behavior: smooth;
}

body {
    background-color: var(--bg-black);
    color: var(--text-light);
    font-family: var(--font-main);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* --- 通用组件 --- */
.container {
    max-width: 980px;
    margin: 0 auto;
    padding: 0 20px;
}

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

h1, h2, h3, h4, p {
    letter-spacing: 0.5px;
}

h1 {
    font-size: 56px;
    font-weight: 600;
    line-height: 1.1;
}

h2 {
    font-size: 48px;
    font-weight: 600;
    line-height: 1.2;
    margin-bottom: 20px;
}

p {
    font-size: 17px;
    line-height: 1.6;
    color: var(--text-secondary);
}

section {
    padding: 120px 0;
    overflow: hidden;
}

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

/* 按钮样式 */
.primary-button, .secondary-button, .cta-button {
    display: inline-block;
    padding: 12px 24px;
    border-radius: 980px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.primary-button {
    background-color: var(--primary-blue);
    color: white;
}
.primary-button:hover {
    background-color: #0077f0;
    transform: scale(1.05);
}

.secondary-button {
    color: var(--primary-blue);
    border: 1px solid transparent;
}
.secondary-button:hover {
    /* text-decoration: underline; */
}

.cta-button {
    background-color: rgba(255, 255, 255, 0.15);
    color: var(--text-light);
    font-size: 14px;
    padding: 8px 16px;
}
.cta-button:hover {
    background-color: rgba(255, 255, 255, 0.25);
}

.primary-button.large {
    font-size: 18px;
    padding: 16px 32px;
}

/* 占位符样式 */
.image-placeholder, .visual-content-placeholder, .showcase-video-placeholder, .workflow-visual-placeholder {
    /* background-color: var(--bg-dark-grey); */
    border-radius: 20px;
    display: flex;
    justify-content: center;
    align-items: center;
    color: var(--text-secondary);
    font-size: 16px;
}
.placeholder-text.large { font-size: 24px; }


/* --- 导航栏 --- */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    /* background-color: rgba(0, 0, 0, 0.7); */
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    /* border-bottom: 1px solid rgba(255, 255, 255, 0.1); */
}

.main-nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.logo {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-light);
    text-decoration: none;
}

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

.nav-links a {
    color: #ffffff;
    text-decoration: none;
    font-size: 15px;
    transition: color 0.3s ease;
}

.nav-links a:hover {
    color: var(--text-secondary);
}

/* --- Hero Section --- */
.hero-section {
    height: 100vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding-top: 80px; /* 留出导航栏空间 */
    position: relative;
}

.hero-video-background {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    z-index: 1;
    /* 将视频容器置于背景层 */
}

.hero-video-background video {
    width: 100%;
    height: 100%;
    object-fit: cover;
    /* 确保视频铺满整个区域且不变形 */
}

/* 添加一个深色半透明遮罩，让文字更易读 */
.hero-video-background::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.5);
    /* 50% 透明度的黑色遮罩 */
}


.hero-content {
    position: relative;
    /* 确保内容在视频之上 */
    z-index: 2;
    /* 将内容层级置于视频和遮罩之上 */
    text-align: center;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
}

.hero-content p {
    font-size: 24px;
    max-width: 600px;
    margin: 20px auto 30px;
    color: var(--text-light);
    opacity: 0.9;
}

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

/* --- Problem Section --- */
.problem-section h2 {
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}
.problem-section p {
    font-size: 21px;
    color: var(--text-light);
    margin-top: 10px;
}
.stats-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
    margin-top: 80px;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}
.stat-item h3 {
    font-size: 32px;
    font-weight: 600;
    color: var(--primary-blue);
}
.stat-item p {
    font-size: 16px;
    margin-top: 5px;
}

/* --- Workflow Section --- */
.workflow-sequence-container {
    height: 400vh;
    position: relative;
}
.workflow-step-panel {
    height: 100vh;
    width: 100%;
    position: sticky;
    top: 0;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 40px;
}
#step-1, #step-3 { background-color: var(--bg-black); }
#step-2, #step-4 { background-color: var(--bg-dark-grey); }
.step-content {
    max-width: 900px;
    width: 100%;
}
.step-content p {
    max-width: 500px;
    margin-left: auto;
    margin-right: auto;
    margin-bottom: 40px;
}
.workflow-visual-placeholder {
    width: 100%;
    aspect-ratio: 16 / 9;
    transition: transform 0.8s ease-out, opacity 0.8s ease-out;
    transform: scale(0.95);
    opacity: 0.8;
}
.workflow-visual-placeholder video,
.showcase-video-placeholder video{
    width: 100%;
    /* height: 100%; */
    border-radius: 20px
}
.workflow-step-panel.is-active .workflow-visual-placeholder {
    transform: scale(1);
    opacity: 1;
}

/* --- Target Audience Section --- */
.target-audience-section {
    background-color: var(--bg-black);
}
.audience-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    margin-top: 60px;
}
.audience-card {
    background-color: var(--bg-dark-grey);
    padding: 30px;
    border-radius: 20px;
    text-align: left;
}
.image-placeholder.tall {
    width: 100%;
    height: 250px;
    margin-bottom: 20px;
}
.audience-card h3 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 10px;
}

/* --- Showcase Section --- */
.showcase-section {
    background-color: var(--bg-dark-grey);
}
.showcase-section p {
    max-width: 500px;
    margin: 10px auto 50px;
}
.showcase-video-placeholder {
    width: 100%;
    aspect-ratio: 16 / 9;
}

/* --- 版权服务 Section (已更新) --- */
.copyright-section {
    background-color: var(--bg-black);
}
.copyright-section p {
    max-width: 600px;
    margin: 0 auto 60px auto;
}
.service-grid {
    display: grid;
    /* 更新为2列布局以适应4个项目 */
    grid-template-columns: repeat(2, 1fr);
    gap: 40px; /* 增大间距 */
}
.service-item {
    background-color: var(--bg-dark-grey);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center; /* 确保内容居中 */
}
.service-item i {
    font-size: 32px;
    color: var(--primary-blue);
    margin-bottom: 20px;
}
.service-item h3 {
    font-size: 21px;
    margin-bottom: 10px;
    color: var(--text-light);
}

/* --- 商单服务 Section --- */
.orders-section {
    background-color: var(--bg-dark-grey);
}
.orders-section p {
    max-width: 600px;
    margin: 0 auto 60px auto;
}
.order-flow-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin-bottom: 60px;
}
.flow-card {
    background-color: var(--bg-black);
    padding: 30px;
    border-radius: 20px;
    width: 300px;
    border: 1px solid var(--border-color);
}
.flow-card i {
    font-size: 24px;
    color: var(--primary-blue);
    margin-bottom: 15px;
}
.flow-card h4 {
    font-size: 20px;
    margin-bottom: 8px;
    color: var(--text-light);
}
.flow-arrow {
    font-size: 32px;
    color: var(--text-secondary);
}
.final-motto {
    font-size: 28px;
    font-weight: 600;
    color: var(--text-light);
}

/* --- 功能矩阵 Section --- */
.features-section {
    background-color: var(--bg-black);
}
.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin-top: 60px;
}
.feature-item {
    background-color: var(--bg-dark-grey);
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
}
.feature-item i {
    font-size: 32px;
    color: var(--primary-blue);
    margin-bottom: 20px;
}
.feature-item h4 {
    font-size: 21px;
    margin-bottom: 10px;
}

/* --- Final CTA Section --- */
.final-cta-section h2 {
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}
.final-cta-section p {
    font-size: 21px;
    color: var(--text-light);
    margin: 20px auto 40px;
    max-width: 500px;
}

/* --- Footer --- */
.main-footer-bottom {
    padding: 40px 0;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 12px;
    background-color: var(--bg-dark-grey);
}
.main-footer-bottom .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.footer-links {
    display: flex;
    gap: 20px;
}
.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
}
.footer-links a:hover {
    color: var(--text-light);
}

/* --- 动画效果 --- */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}
.fade-in.is-visible {
    opacity: 1;
    transform: translateY(0);
}
/* 为不同元素设置延迟 */
.fade-in:nth-child(2) { transition-delay: 0.1s; }
.fade-in:nth-child(3) { transition-delay: 0.2s; }
.fade-in:nth-child(4) { transition-delay: 0.3s; }
.stats-grid .fade-in, .audience-grid .fade-in, .features-grid .fade-in, .service-grid .fade-in {
    transition-delay: var(--delay, 0s);
}

/* --- 响应式设计 --- */
@media (max-width: 768px) {
    h1 { font-size: 40px; }
    h2 { font-size: 32px; }
    p { font-size: 16px; }
    section { padding: 80px 20px; }
    
    .nav-links { display: none; }

    .hero-content p { font-size: 18px; }

    .stats-grid, .service-grid { grid-template-columns: 1fr; }
    
    .workflow-sequence-container { height: auto; }
    .workflow-step-panel {
        height: auto;
        position: static;
        padding: 80px 20px;
    }

    .order-flow-container { flex-direction: column; }
    .flow-arrow { transform: rotate(90deg); margin: 20px 0; }
    .flow-card { width: 100%; }
}

/* ===== 新增：二维码悬浮弹出框样式 ===== */

/* 1. 触发器容器 (包裹链接和弹出框) */
.hover-qr-container {
    position: relative; /* 这是关键，为内部绝对定位的弹出框提供基准 */
    display: inline-block; /* 使容器的宽度适应内容，且不换行 */
}

/* 2. 弹出框本身 (默认隐藏) */
.qr-popover {
    visibility: hidden; /* 完全隐藏，不占空间，不可交互 */
    opacity: 0; /* 透明度为0 */
    position: absolute; /* 绝对定位，相对于.hover-qr-container */
    bottom: 100%; /* 定位到容器的顶部 */
    left: 50%; /* 水平居中第一步 */
    transform: translateX(-50%); /* 水平居中第二步 */
    margin-bottom: 10px; /* 在链接和弹出框之间留出一些间距 */
    
    /* 弹出框外观 */
    width: 160px; /* 固定宽度 */
    background-color: #ffffff;
    padding: 15px;
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.15);
    text-align: center;
    z-index: 10; /* 确保在其他元素之上 */
    
    /* 平滑过渡效果 */
    transition: opacity 0.3s ease, visibility 0.3s ease;
    pointer-events: none; /* 隐藏时不可点击 */
}

/* 3. 弹出框内部的图片和文字样式 */
.qr-popover img {
    width: 100%; /* 图片宽度撑满弹出框 */
    display: block; /* 避免图片下方有空隙 */
    border-radius: 4px;
}

.qr-popover p {
    margin: 10px 0 0 0; /* 图片和文字之间的间距 */
    font-size: 12px;
    color: #333;
    font-weight: bold;
}

/* 4. 鼠标悬浮在容器上时，显示弹出框 */
.hover-qr-container:hover .qr-popover {
    visibility: visible; /* 使其可见 */
    opacity: 1; /* 完全不透明 */
    pointer-events: auto; /* 可见时恢复交互 */
}
/* ===== CSS样式结束 ===== */