/* --- 1. Design System --- */
:root {
    --primary: #0f172a;       
    --accent: #2563eb;        
    --accent-hover: #1d4ed8;
    --text-main: #1e293b;
    --text-muted: #64748b;
    --text-light: #94a3b8;
    --bg-white: #ffffff;
    --bg-light: #f8fafc;
    --max-width: 1200px;
    --radius: 8px;
}

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

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: var(--text-main);
    line-height: 1.6;
    background-color: var(--bg-white);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

a { text-decoration: none; transition: 0.2s; }
img { display: block; width: 100%; height: auto; }
ul { list-style: none; }

.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
}

.section { padding: 100px 0; }
#contact { padding-bottom: 60px; } /* 稍微增加一点底部距离，避免太挤 */
.bg-light { background-color: var(--bg-light); }

/* --- 2. Navigation --- */
header {
    position: fixed;
    top: 0; width: 100%; height: 80px; z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid #e2e8f0;
}
.nav-inner {
    height: 100%;
    display: grid;
    grid-template-columns: 240px 1fr auto; /* 右侧自适应 */
    align-items: center;
    gap: 20px;
}
.logo-wrapper { display: flex; flex-direction: column; justify-content: center; }
.logo { font-size: 1.1rem; font-weight: 800; color: var(--primary); line-height: 1.1; letter-spacing: -0.02em; }
.logo-tag { font-size: 0.65rem; text-transform: uppercase; letter-spacing: 2px; color: var(--text-muted); font-weight: 600; margin-top: 3px; }
/* --- 新增：Logo 图片适配样式 --- */
.logo-wrapper {
    display: flex;
    align-items: center; /* 垂直居中 */
    height: 100%;
    text-decoration: none;
}

.site-logo {
    display: block;
    height: 80px;        /* 限制高度，Header高80px，44px很协调 */
    width: auto;         /* 宽度自动保持比例 */
    object-fit: contain; /* 防止图片变形 */
}

.nav-menu { display: flex; justify-content: center; gap: 40px; }
.nav-menu a { font-size: 0.95rem; font-weight: 500; color: var(--text-main); position: relative; cursor: pointer; white-space: nowrap; }
.nav-menu a:hover { color: var(--accent); }
.nav-menu a::after { content: ''; position: absolute; bottom: -4px; left: 0; width: 0; height: 2px; background: var(--accent); transition: width 0.3s; }
.nav-menu a:hover::after { width: 100%; }

/* --- 右侧按钮组样式修复 --- */
.nav-actions { 
    display: flex; 
    justify-content: flex-end; 
    align-items: center; 
    gap: 12px; /* 按钮之间的间距 */
}

/* 修复开发者按钮：强制不换行，统一高度 */
.btn-nav { 
    background: var(--primary); 
    color: white; 
    padding: 0 20px; /* 左右内边距 */
    height: 40px;    /* 固定高度 */
    line-height: 40px; /* 文字垂直居中 */
    border-radius: 6px; 
    font-size: 0.9rem; 
    font-weight: 600; 
    border: 1px solid var(--primary); 
    white-space: nowrap; /* 核心修复：禁止文字换行 */
    display: inline-flex;
    align-items: center;
    justify-content: center;
}
.btn-nav:hover { background: white; color: var(--primary); }

/* --- Language Dropdown (精致小巧版) --- */
.lang-dropdown { 
    position: relative; 
    display: inline-flex; 
    align-items: center;  
    /* 容器高度跟随内容，靠 flex 居中 */
    z-index: 1100;
}

/* 当前语言显示按钮 */
.current-lang {
    background: transparent;
    border: 1px solid #e2e8f0;
    /* 调整：减小内边距 */
    padding: 0 10px;
    /* 调整：高度减小到 34px (比右边的 40px 按钮小一圈) */
    height: 34px;    
    border-radius: 6px;
    cursor: pointer;
    /* 调整：字体变小 */
    font-size: 0.85rem; 
    font-weight: 600;
    color: var(--text-main);
    display: flex; 
    align-items: center; 
    justify-content: center;
    gap: 6px;
    transition: all 0.2s;
    white-space: nowrap; 
    /* 调整：最小宽度减小 */
    min-width: 100px;
    background-color: #fff;
    margin: 0; 
}
.current-lang:hover { border-color: var(--accent); color: var(--accent); background-color: #f8fafc; }

.arrow-icon { opacity: 0.6; transition: transform 0.2s; flex-shrink: 0; width: 10px; height: 10px; /* 图标也稍微缩小 */ }

/* 下拉菜单容器 */
.lang-menu {
    display: block; 
    opacity: 0;
    visibility: hidden;
    position: absolute; 
    top: 100%; 
    right: 0; 
    margin-top: 8px; /* 间距微调 */
    background: #ffffff; 
    /* 调整：菜单宽度跟随按钮 */
    min-width: 100px;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    border-radius: 8px; 
    border: 1px solid #e2e8f0; 
    transition: all 0.2s ease-in-out; 
    transform: translateY(-10px); 
}

/* --- 隐形桥梁 (保持交互顺滑) --- */
.lang-menu::before {
    content: "";
    position: absolute;
    top: -15px; 
    left: 0;
    width: 100%;
    height: 15px; 
    background: transparent; 
}

.lang-option { 
    /* 调整：选项内边距减小 */
    padding: 10px 14px; 
    /* 调整：字体变小 */
    font-size: 0.85rem; 
    color: var(--text-main); 
    cursor: pointer; 
    transition: background 0.2s; 
    font-weight: 500; 
    text-align: left; 
    white-space: nowrap; 
}

/* 圆角处理 */
.lang-option:first-child { border-top-left-radius: 8px; border-top-right-radius: 8px; }
.lang-option:last-child { border-bottom-left-radius: 8px; border-bottom-right-radius: 8px; }

.lang-option:hover { background-color: #f1f5f9; color: var(--accent); }

/* 鼠标悬停逻辑 */
.lang-dropdown:hover .lang-menu { 
    opacity: 1;
    visibility: visible;
    transform: translateY(0); 
}
.lang-dropdown:hover .arrow-icon { transform: rotate(180deg); }


/* --- 3. Hero --- */
.hero { position: relative; padding-top: 180px; padding-bottom: 120px; background: linear-gradient(180deg, #f0f9ff 0%, #ffffff 100%); overflow: hidden; text-align: center; }
.hero-bg-img { position: absolute; top: 0; left: 0; width: 100%; height: 100%; background-image: url('https://images.unsplash.com/photo-1451187580459-43490279c0fa?ixlib=rb-1.2.1&auto=format&fit=crop&w=1950&q=80'); background-size: cover; background-position: center; opacity: 0.1; z-index: 0; filter: grayscale(100%); }
.hero-content { position: relative; z-index: 2; max-width: 900px; margin: 0 auto; }
.hero-badge { display: inline-flex; align-items: center; gap: 8px; background: #eff6ff; border: 1px solid #dbeafe; color: var(--accent); padding: 8px 16px; border-radius: 50px; font-size: 0.85rem; font-weight: 600; margin-bottom: 32px; text-transform: uppercase; letter-spacing: 0.5px; }
.hero-badge::before { content: ''; width: 6px; height: 6px; background: var(--accent); border-radius: 50%; }
.hero h1 { font-size: 3.5rem; font-weight: 800; line-height: 1.1; margin-bottom: 24px; color: var(--primary); letter-spacing: -0.03em; }
.hero p { font-size: 1.25rem; color: var(--text-muted); margin-bottom: 40px; max-width: 650px; margin-left: auto; margin-right: auto; line-height: 1.6; }
.btn-hero { display: inline-flex; align-items: center; padding: 16px 40px; background: var(--accent); color: white; font-weight: 600; border-radius: 8px; font-size: 1.05rem; box-shadow: 0 10px 25px -5px rgba(37, 99, 235, 0.4); transition: 0.3s; }
.btn-hero:hover { background: var(--accent-hover); transform: translateY(-2px); box-shadow: 0 15px 30px -5px rgba(37, 99, 235, 0.5); }

/* --- 4. Security Bar --- */
.security-bar { background: #ffffff; padding: 20px 0 60px; border-bottom: 1px solid #e2e8f0; }
.sec-flex { display: flex; justify-content: center; gap: 60px; flex-wrap: wrap; }
.sec-item { display: flex; align-items: center; gap: 12px; font-weight: 600; color: var(--text-muted); font-size: 1rem; }
.sec-item svg { width: 22px; height: 22px; fill: var(--primary); opacity: 0.8; }

/* --- 5. Story --- */
.section-header { text-align: center; max-width: 700px; margin: 0 auto 60px; }
.section-header h2 { font-size: 2.25rem; color: var(--primary); margin-bottom: 16px; font-weight: 800; letter-spacing: -0.5px; }
.section-header p { font-size: 1.1rem; color: var(--text-muted); }
.story-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 80px; align-items: center; }
.story-text h3 { color: var(--accent); text-transform: uppercase; font-size: 0.85rem; letter-spacing: 1.2px; font-weight: 700; margin-bottom: 12px; }
.story-text h2 { font-size: 2.25rem; font-weight: 800; color: var(--primary); margin-bottom: 24px; line-height: 1.2; }
.story-text p { margin-bottom: 20px; color: var(--text-muted); font-size: 1.05rem; text-align: justify; }
.story-img { border-radius: 16px; overflow: hidden; box-shadow: 0 20px 40px -10px rgba(0,0,0,0.1); border: 1px solid #e2e8f0; }

/* --- 6. Features (Clickable Grid Layout) --- */
.features-section {
    padding: 0;
}

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

/* 卡片变成链接后的样式 */
.feature-card {
    display: block; /* 让 a 标签变成块级元素 */
    background: white;
    padding: 40px 32px;
    border-radius: 16px;
    border: 1px solid #e2e8f0;
    transition: all 0.3s ease;
    text-decoration: none; /* 去掉下划线 */
    height: 100%; /* 保证高度一致 */
    position: relative;
    top: 0;
}

/* 悬停效果：上浮 + 阴影加深 + 边框变蓝 */
.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 20px 40px -5px rgba(0, 0, 0, 0.1);
    border-color: var(--accent);
}

/* 图标容器 */
.icon-box {
    width: 56px;
    height: 56px;
    background: #eff6ff;
    color: var(--accent);
    border-radius: 14px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    transition: 0.3s;
}

/* 悬停时图标背景变深 */
.feature-card:hover .icon-box {
    background: var(--accent);
    color: white;
}

.icon-box svg {
    width: 28px;
    height: 28px;
    fill: currentColor;
}

/* 标题和文字 */
.feature-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    margin-bottom: 12px;
    color: var(--primary);
}

.feature-card p {
    font-size: 1rem;
    color: var(--text-muted);
    line-height: 1.6;
}

/* “了解更多” 箭头提示 */
.learn-more {
    margin-top: 20px;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--accent);
    display: flex;
    align-items: center;
    gap: 5px;
    opacity: 0; /* 默认隐藏 */
    transform: translateX(-10px);
    transition: all 0.3s ease;
}

.feature-card:hover .learn-more {
    opacity: 1;
    transform: translateX(0);
}

/* 响应式 */
@media (max-width: 1024px) {
    .features-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 600px) {
    .features-grid { grid-template-columns: 1fr; }
}

/* --- 7. Contact --- */
.contact-box { display: grid; grid-template-columns: 380px 1fr; background: white; border-radius: 20px; overflow: hidden; border: 1px solid #e2e8f0; box-shadow: 0 20px 25px -5px rgba(0,0,0,0.1); }
.contact-info { padding: 60px; background: #f8fafc; border-right: 1px solid #e2e8f0; }
.contact-info h3 { font-size: 1.5rem; font-weight: 800; color: var(--primary); margin-bottom: 32px; }
.info-row { margin-bottom: 28px; }
.info-row label { display: block; font-size: 0.75rem; text-transform: uppercase; font-weight: 700; letter-spacing: 0.5px; color: #94a3b8; margin-bottom: 6px; }
.info-row p, .info-row a { font-size: 1.05rem; font-weight: 600; color: var(--primary); }
.info-row a { color: var(--accent); }
.contact-map iframe { width: 100%; height: 100%; min-height: 450px; border: 0; }

/* --- 8. Footer (Compact) --- */
footer { background-color: var(--bg-white); border-top: 1px solid #e2e8f0; padding: 24px 0; margin-top: auto; }
.footer-flex { display: flex; justify-content: space-between; align-items: center; }
.copyright { font-size: 0.85rem; color: var(--text-light); font-weight: 500; }
.footer-links { display: flex; gap: 24px; }
.footer-links a { font-size: 0.85rem; color: var(--text-muted); font-weight: 500; }
.footer-links a:hover { color: var(--primary); }

/* --- Privacy Page Specifics --- */
.back-link { color: #64748b; text-decoration: none; font-size: 0.95rem; font-weight: 500; transition: 0.2s; }
.back-link:hover { color: #2563eb; }
.page-header { border-bottom: 1px solid #e2e8f0; padding-bottom: 20px; margin-bottom: 40px; }
.page-header h2 { margin-top: 0; font-size: 2.2rem; color: #0f172a; font-weight: 800; letter-spacing: -0.02em; }
.last-updated { color: #64748b; font-size: 1rem; margin-top: 10px; }
main { padding: 60px 24px; max-width: 900px; margin: 0 auto; }
main p { margin-bottom: 24px; font-size: 16px; line-height: 1.6; color: #334155; text-align: justify; }
main strong { color: #0f172a; font-weight: 700; font-size: 16px; display: block; margin-bottom: 8px; margin-top: 32px; }
main p:first-of-type strong { margin-top: 0; }
main a { color: #2563eb; text-decoration: none; }
main a:hover { text-decoration: underline; }
.contact-box-privacy { background: #f8fafc; border: 1px solid #e2e8f0; padding: 35px; border-radius: 12px; margin-top: 40px; }
.contact-box-privacy p { margin-bottom: 10px; font-size: 16px; margin-top: 0; }
.contact-box-privacy strong { margin-top: 0; margin-bottom: 15px; font-size: 18px; color: #2563eb; display: block; }

/* Responsive */
@media (max-width: 1024px) {
    .nav-inner { grid-template-columns: 1fr auto; }
    .nav-menu { display: none; }
    .hero h1 { font-size: 2.8rem; }
    .story-grid, .features-grid, .contact-box { grid-template-columns: 1fr; }
    .footer-flex { flex-direction: column; gap: 15px; text-align: center; }
}



/* --- 新增：登录按钮样式 (放在 Developer Access 旁边) --- */
.btn-login {
    background: transparent;
    color: var(--text-main);
    padding: 10px 24px;
    border-radius: 6px;
    font-size: 0.9rem;
    font-weight: 600;
    border: 1px solid #e2e8f0;
    transition: 0.2s;
    text-decoration: none;
    white-space: nowrap;
}
.btn-login:hover {
    border-color: var(--primary);
    color: var(--primary);
    background-color: #f8fafc;
}

/* --- Login Page Layout Fix --- */
.login-section {
    display: flex;
    /* 修改 1：改为顶部对齐，不再自动居中，这样我们可以控制它离顶部多远 */
    align-items: flex-start; 
    justify-content: center;
    
    /* 修改 2：确保背景铺满全屏 */
    min-height: 100vh; 
    
    /* 修改 3：大幅增加顶部间距 
       计算公式：Header高度(80px) + 想要的视觉空隙(约100px) = 180px */
    padding-top: 180px; 
    
    padding-bottom: 80px; /* 底部也留点空间 */
    padding-left: 20px;
    padding-right: 20px;
    
    background-color: var(--bg-light);
}

.login-card {
    background: white;
    width: 100%;
    max-width: 420px;
    padding: 40px;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -2px rgba(0, 0, 0, 0.06);
    border: 1px solid #e2e8f0;
    text-align: center;
}

.login-header h2 {
    font-size: 1.75rem;
    color: var(--primary);
    margin-bottom: 10px;
    font-weight: 700;
}

.login-header p {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 30px;
}

.login-form .form-group {
    margin-bottom: 20px;
    text-align: left;
}

.login-form label {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--text-main);
    margin-bottom: 8px;
}

.login-form input {
    width: 100%;
    padding: 12px;
    border: 1px solid #cbd5e1;
    border-radius: 8px;
    font-size: 1rem;
    transition: 0.2s;
    font-family: inherit;
}

.login-form input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.btn-submit {
    width: 100%;
    background-color: var(--accent);
    color: white;
    padding: 12px;
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: 0.2s;
    margin-top: 10px;
}

.btn-submit:hover {
    background-color: var(--accent-hover);
}

.login-footer {
    margin-top: 24px;
    font-size: 0.9rem;
    color: var(--text-muted);
}

.login-footer a {
    color: var(--accent);
    font-weight: 500;
}

/* --- Products Page Specific Styles (Left Text / Right Image) --- */

/* 页面头部 */
.page-hero {
    text-align: center;
    padding-top: 160px;
    padding-bottom: 80px;
    background: linear-gradient(180deg, #f0f9ff 0%, #fff 100%);
}
.page-hero h1 { font-size: 3rem; color: var(--primary); margin-bottom: 20px; font-weight: 800; }
.page-hero p { font-size: 1.2rem; color: var(--text-muted); max-width: 700px; margin: 0 auto; }

/* 详细功能行 */
.product-row {
    padding: 80px 0;
    border-bottom: 1px solid #f1f5f9;
}
/* 偶数行背景微灰，增加层次 */
.product-row:nth-child(even) { background-color: #f8fafc; }

.product-split {
    display: flex;
    align-items: center;
    gap: 60px;
}

/* 文本区域 */
.prod-text { flex: 1; }
.prod-text h3 {
    font-size: 2rem;
    color: var(--primary);
    margin-bottom: 20px;
    font-weight: 700;
}
.prod-text p {
    font-size: 1.05rem;
    color: var(--text-muted);
    line-height: 1.7;
    margin-bottom: 24px;
}

/* 列表样式 */
.prod-features { list-style: none; margin-bottom: 30px; }
.prod-features li {
    position: relative;
    padding-left: 28px;
    margin-bottom: 12px;
    font-size: 1rem;
    color: var(--text-main);
    font-weight: 500;
}
/* 蓝色勾选图标 */
.prod-features li::before {
    content: '✔';
    position: absolute;
    left: 0; top: 0;
    color: var(--accent);
    font-weight: bold;
    font-size: 1.1rem;
}

/* 图片区域 */
.prod-img {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}
/* 图片占位符样式 (如果没有图片，显示灰色方块) */
.img-placeholder {
    width: 100%;
    max-width: 550px;
    height: 320px;
    background-color: #e2e8f0;
    border: 2px dashed #cbd5e1;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    font-weight: 600;
    font-size: 1.2rem;
}
/* 真实图片样式 */
.prod-img img {
    width: 100%;
    max-width: 550px;
    border-radius: 12px;
    box-shadow: 0 20px 50px -10px rgba(15, 23, 42, 0.1);
    border: 1px solid #e2e8f0;
}

/* 响应式：手机端垂直排列 */
@media (max-width: 900px) {
    .product-split { flex-direction: column; }
    .img-placeholder { height: 200px; }
}

/* --- 修复：从其他页面跳转回主页锚点时的遮挡问题 --- */
html {
    /* 核心修复：告诉浏览器，滚动到锚点时，上方要预留多少空间 */
    /* Header高度(80px) + 额外留白(40px) = 120px */
    scroll-padding-top: 120px; 
    
    /* 保持平滑滚动 */
    scroll-behavior: smooth;
}

/* 针对旧版浏览器的兼容性处理 (以防万一) */
:target {
    scroll-margin-top: 120px;
}







/* --- Pricing Page Styles (Comparison Layout) --- */
.pricing-section {
    padding: 60px 0 100px;
    background-color: var(--bg-white);
}

/* 网格改为两列，且卡片更宽 */
.pricing-grid {
    display: grid;
    grid-template-columns: 1fr 1fr; /* 1:1 等宽 */
    gap: 40px;
    max-width: 1000px; /* 限制最大宽度 */
    margin: 0 auto;
    align-items: stretch; /* 高度拉伸一致 */
}

.pricing-card {
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 16px;
    padding: 0; /* 内部 padding 由子元素控制 */
    display: flex;
    flex-direction: column;
    transition: 0.3s;
    position: relative;
    overflow: hidden;
}

/* 头部区域 */
.price-head {
    padding: 40px 40px 20px;
    border-bottom: 1px solid #f1f5f9;
    text-align: center;
}

.price-head h3 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: 10px;
}

.price-desc {
    color: var(--text-muted);
    font-size: 0.95rem;
    margin-bottom: 20px;
    min-height: 48px; /* 保证两边描述对齐 */
}

.price-num {
    font-size: 3.5rem;
    font-weight: 800;
    color: var(--primary);
    font-family: 'Inter', sans-serif;
    line-height: 1;
}

.price-period {
    font-size: 1rem;
    color: var(--text-muted);
    font-weight: 500;
}

/* 列表区域 */
.price-body {
    padding: 40px;
    flex: 1; /* 撑满剩余空间 */
    background: #fafafa; /* 淡淡的灰色背景 */
}

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

.price-features li {
    margin-bottom: 16px;
    color: var(--text-main);
    font-size: 1rem;
    position: relative;
    padding-left: 30px;
    line-height: 1.5;
}

/* 绿色对勾 */
.price-features li::before {
    content: '✔';
    position: absolute;
    left: 0;
    top: 2px;
    color: #10b981;
    font-weight: bold;
    font-size: 1.1rem;
}

/* 专业版特殊样式 */
.pricing-card.popular {
    border-color: var(--accent);
    box-shadow: 0 20px 50px -10px rgba(37, 99, 235, 0.15);
    transform: scale(1.02); /* 微微放大，突出C位 */
    z-index: 2;
}

/* 头部背景变蓝 */
.pricing-card.popular .price-head {
    background: #eff6ff;
    border-bottom: 1px solid #dbeafe;
}

.pricing-card.popular .price-body {
    background: #fff;
}

.popular-badge {
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    background: var(--accent);
    color: white;
    padding: 6px 20px;
    border-radius: 0 0 12px 12px; /* 下方圆角 */
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* 按钮区域 */
.price-footer {
    padding: 30px 40px;
    background: #fff;
    border-top: 1px solid #f1f5f9;
}

/* 响应式 */
@media (max-width: 800px) {
    .pricing-grid { grid-template-columns: 1fr; }
    .pricing-card.popular { transform: none; }
}