:root {
    /* 主色系 */
    --primary: #2563eb;
    --primary-light: #3b82f6;
    --primary-dark: #1d4ed8;
    
    /* 中性色 */
    --neutral-50: #f9fafb;
    --neutral-100: #f3f4f6;
    --neutral-200: #e5e7eb;
    --neutral-300: #d1d5db;
    --neutral-400: #9ca3af;
    --neutral-500: #6b7280;
    --neutral-600: #4b5563;
    --neutral-700: #374151;
    --neutral-800: #1f2937;
    --neutral-900: #111827;
    
    /* 其他 */
    --container-width: min(1280px, calc(100% - 48px));
    --transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    --shadow-sm: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -1px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    
    /* 特定颜色 */
    --feature-bg: #f0f9ff;
    --feature-text: #0ea5e9;
    --fix-bg: #fff7ed;
    --fix-text: #ea580c;
    --optimize-bg: #fffbeb;
    --optimize-text: #d97706;
    --security-bg: #fef2f2;
    --security-text: #ef4444;
}

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

:root {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, 
                 Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--neutral-700);
    background-color: var(--neutral-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

/* 页眉样式 - 现代化设计 */
.site-header {
    background-color: white;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 100;
    padding: 16px 0;
    transition: var(--transition);
}

.site-header.scrolled {
    box-shadow: 0 4px 20px -2px rgba(0, 0, 0, 0.1);
    padding: 12px 0;
}

.site-header .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0;
}

.logo {
    display: flex;
    align-items: center;
    height: 40px;
}

.logo a {
    display: flex;
    align-items: center;
    height: 100%;
}

.logo img {
    height: 25px;
    width: 140px;
}

.main-nav {
    display: flex;
    align-items: center;
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 28px;
}

/* 修复下拉菜单定位问题 */
.has-dropdown {
    position: relative; /* 必须添加，使下拉菜单能相对于此元素定位 */
}

.main-nav li a {
    font-weight: 500;
    position: relative;
    padding: 4px 0;
    color: var(--neutral-600);
    display: flex;
    align-items: center;
    transition: var(--transition);
    height: 100%;
}

.main-nav li a.active,
.main-nav li a:hover {
    color: var(--primary);
}

.main-nav li a.active::after,
.main-nav li a:hover::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 2px;
    background-color: var(--primary);
    border-radius: 1px;
}

.dropdown-icon {
    font-size: 0.65rem;
    margin-left: 6px;
    color: var(--neutral-500);
    transition: transform 0.3s;
}

/* 下拉菜单样式 - 修复居中问题 */
.dropdown-menu {
    position: absolute;
    top: 100%; /* 确保下拉菜单在导航项下方 */
    left: 50%; /* 关键修复：从左侧50%开始 */
    transform: translateX(-50%); /* 关键修复：向左移动自身宽度的50% */
    width: max-content;
    max-width: calc(100vw - 40px);
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    transform: translateX(-50%) translateY(10px);
    visibility: hidden;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    z-index: 1000;
    min-width: 320px;
    margin-top: 8px;
}

.has-dropdown:hover .dropdown-menu {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
    visibility: visible;
}

/* 解决方案下拉菜单 - 修复宽度问题 */
.solution-dropdown {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
    padding: 16px;
    min-width: 640px; /* 固定宽度确保内容居中 */
    max-width: 640px;
}

/* 帮助中心和关于我们下拉菜单 */
.help-dropdown,
.about-dropdown {
    padding: 8px 0;
    min-width: 320px;
    max-width: 320px;
}

.dropdown-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.dropdown-item {
    display: flex;
    align-items: flex-start;
    padding: 16px;
    border-radius: var(--radius-md);
    transition: var(--transition);
    text-decoration: none;
    color: var(--neutral-800);
    width: 100%;
}

.dropdown-item:hover {
    background-color: var(--neutral-50);
    transform: translateX(4px);
}

.icon-container {
    width: 40px;
    height: 40px;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 10px;
    background-color: var(--neutral-50);
    margin-right: 16px;
    flex-shrink: 0;
}

.icon-container svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: var(--primary);
}

.item-content {
    flex: 1;
}

.item-title {
    font-weight: 600;
    color: var(--neutral-800);
    margin-bottom: 4px;
    font-size: 1.05rem;
}

.item-desc {
    color: var(--neutral-500);
    font-size: 0.85rem;
    margin-bottom: 8px;
}

.item-features {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
    margin-top: 8px;
}

.item-features span {
    background: var(--neutral-50);
    color: var(--neutral-600);
    padding: 2px 8px;
    border-radius: 20px;
    font-size: 0.75rem;
}

/* 按钮样式 */
.btn {
    padding: 8px 20px;
    border-radius: var(--radius-md);
    font-weight: 500;
    font-size: 0.95rem;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    text-decoration: none;
    border: none;
    height: 40px;
}

.btn-outline {
    background-color: transparent;
    color: var(--neutral-700);
    border: 1px solid var(--neutral-300);
}

.btn-outline:hover {
    background-color: var(--neutral-100);
    color: var(--neutral-800);
    border-color: var(--neutral-400);
}

.btn-primary {
    background-color: var(--primary);
    color: white;
    margin-left: 12px;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.25);
}

/* 联系信息 */
.contact-info {
    display: none;
    flex-direction: column;
    align-items: flex-end;
    margin-right: 24px;
    text-decoration: none;
}

.contact-info .phone-number {
    font-weight: 600;
    color: var(--neutral-800);
    font-size: 1.1rem;
}

.contact-info .working-hours {
    color: var(--neutral-500);
    font-size: 0.85rem;
    margin-top: 2px;
}

/* 更新日志标签 */
.update-badge {
    background-color: var(--primary);
    color: white;
    font-size: 0.65rem;
    padding: 2px 6px;
    border-radius: 10px;
    margin-left: 8px;
    font-weight: 600;
}

/* 移动菜单按钮 */
.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    justify-content: space-between;
    width: 28px;
    height: 22px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0;
}

.mobile-menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--neutral-700);
    border-radius: 1px;
    transition: var(--transition);
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: translateY(9px) rotate(45deg);
}
.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}
.mobile-menu-toggle.active span:nth-child(3) {
    transform: translateY(-9px) rotate(-45deg);
}

/* 响应式设计 */
@media (max-width: 992px) {
    .main-nav {
        position: fixed;
        top: 72px;
        right: -100%;
        width: 80%;
        max-width: 360px;
        height: calc(100vh - 72px);
        background: white;
        box-shadow: -5px 0 15px rgba(0, 0, 0, 0.05);
        z-index: 99;
        transition: var(--transition);
        padding: 20px;
        overflow-y: auto;
    }
    
    .main-nav.active {
        right: 0;
    }
    
    .main-nav ul {
        flex-direction: column;
        gap: 16px;
    }
    
    /* 移动端下拉菜单样式 */
    .dropdown-menu {
        position: static;
        left: auto;
        transform: none;
        box-shadow: none;
        opacity: 1;
        visibility: visible;
        display: none;
        width: 100%;
        padding: 0;
        margin-top: 8px;
        z-index: auto;
        max-width: none;
    }
    
    .has-dropdown.open .dropdown-menu {
        display: block;
    }
    
    .solution-dropdown {
        grid-template-columns: 1fr;
        padding: 0;
        min-width: auto;
        max-width: none;
    }
    
    .dropdown-grid {
        grid-template-columns: 1fr;
    }
    
    .contact-info {
        display: flex;
    }
}

@media (max-width: 768px) {
    .mobile-menu-toggle {
        display: flex;
    }
    
    .contact-info {
        display: none;
    }
    
    .btn-primary {
        margin-left: 0;
    }
    
    .update-badge {
        display: none;
    }
}

@media (max-width: 480px) {
    .logo img {
        height: 32px;
    }
    
    .btn {
        padding: 8px 16px;
        font-size: 0.85rem;
    }
    
    .main-nav {
        width: 90%;
    }
}

/* footer底部信息 */
.site-footer {
    background: #1a2b4d;
    color: #e0e6f2;
    padding: 40px 0 20px;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 响应式网格布局 */
.footer-top {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 30px 20px;
    margin-bottom: 35px;
}

.footer-column {
    min-width: 180px;
}

.footer-title {
    color: #fff;
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: #4da6ff;
}

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

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

.footer-links a {
    color: #a0b0d0;
    text-decoration: none;
    transition: color 0.3s;
    display: inline-block;
}

.footer-links a:hover {
    color: #4da6ff;
}

/* 联系方式优化 */
.contact-link {
    display: flex;
    align-items: center;
    color: #a0b0d0;
    text-decoration: none;
}

.contact-icon {
    margin-right: 10px;
    width: 20px;
    height: 20px;
    filter: brightness(0) invert(1);
}

/* 二维码区域 */
.qr-code {
    text-align: center;
}

.qr-image {
    width: 120px;
    height: 120px;
    border-radius: 8px;
    object-fit: cover;
    background: #fff;
    padding: 5px;
}

.qr-label {
    margin-top: 10px;
    color: #c0d0e0;
    font-size: 14px;
}

/* 企业信息 */
.company-info {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.footer-logo {
    height: 40px;
    width: auto;
}

.tech-cert {
    display: flex;
    align-items: flex-start;
    gap: 10px;
}

.tech-icon {
    width: 32px;
    height: 32px;
    margin-top: 3px;
}

.cert-text {
    font-size: 13px;
    line-height: 1.4;
}

.cert-id {
    color: #4da6ff;
    font-weight: 500;
}

/* 软件列表 */
.footer-software {
    border-top: 1px solid #2a3c5d;
    padding: 20px 0;
    margin-bottom: 25px;
}

.software-list {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 15px;
    list-style: none;
    padding: 0;
    margin: 0;
    color: #b0c0e0;
    font-size: 14px;
    line-height: 1.6;
}

/* 版权信息 */
.footer-bottom {
    text-align: center;
    padding-top: 20px;
    border-top: 1px solid #2a3c5d;
    color: #7a8ab0;
    font-size: 13px;
}

.legal-links {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-top: 10px;
}

.legal-link {
    color: #9ab0d0;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 5px;
}

.beian-icon {
    width: 16px;
    height: 16px;
    vertical-align: middle;
}

/* 移动端优化 */
@media (max-width: 768px) {
    .footer-top {
        grid-template-columns: 1fr 1fr;
    }
    
    .software-list {
        grid-template-columns: 1fr;
    }
    
    .copyright {
        line-height: 1.5;
    }
}