/* 企业单页模板样式 */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    color: #333;
    line-height: 1.6;
    background: #fff;
}

a { color: inherit; text-decoration: none; }
ul { list-style: none; }
img { max-width: 100%; display: block; }

.container {
    max-width: 1140px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 12px 32px;
    border-radius: 6px;
    font-size: 15px;
    font-weight: 500;
    cursor: pointer;
    border: 2px solid transparent;
    transition: all 0.3s ease;
}

.btn-primary {
    background: #2563eb;
    color: #fff;
    border-color: #2563eb;
}

.btn-primary:hover {
    background: #1d4ed8;
    border-color: #1d4ed8;
}

.btn-outline {
    background: transparent;
    color: #fff;
    border-color: rgba(255,255,255,0.8);
}

.btn-outline:hover {
    background: rgba(255,255,255,0.15);
}

.btn-block { width: 100%; text-align: center; }

/* 顶部导航 */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: transparent;
    transition: background 0.3s, box-shadow 0.3s;
}

.header.scrolled {
    background: rgba(255,255,255,0.97);
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    font-size: 20px;
    font-weight: 700;
    color: #fff;
    transition: color 0.3s;
}

.header.scrolled .logo { color: #1e293b; }

.nav ul {
    display: flex;
    gap: 32px;
}

.nav-link {
    font-size: 15px;
    color: rgba(255,255,255,0.9);
    transition: color 0.3s;
    position: relative;
}

.nav-link:hover { color: #fff; }
.header.scrolled .nav-link { color: #475569; }
.header.scrolled .nav-link:hover { color: #2563eb; }

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: #fff;
    transition: all 0.3s;
}

.header.scrolled .nav-toggle span { background: #333; }

/* 首页横幅 */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #1e3a5f 0%, #2563eb 50%, #3b82f6 100%);
    overflow: hidden;
}

.hero-overlay {
    position: absolute;
    inset: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.04'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    position: relative;
    z-index: 1;
    padding: 120px 20px 80px;
    text-align: center;
    color: #fff;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    margin-bottom: 20px;
    letter-spacing: 2px;
}

.hero-subtitle {
    font-size: 18px;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto 40px;
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
}

/* 通用区块 */
.section {
    padding: 80px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-header h2 {
    font-size: 32px;
    color: #1e293b;
    margin-bottom: 12px;
}

.section-header p {
    font-size: 16px;
    color: #64748b;
}

/* 关于我们 */
.about { background: #f8fafc; }

.about-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
    align-items: center;
}

.about-text p {
    margin-bottom: 16px;
    color: #475569;
    font-size: 15px;
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    margin-top: 32px;
}

.about-stats li {
    text-align: center;
    padding: 16px;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
}

.about-stats strong {
    display: block;
    font-size: 28px;
    color: #2563eb;
    margin-bottom: 4px;
}

.about-stats span {
    font-size: 13px;
    color: #94a3b8;
}

.about-placeholder {
    background: linear-gradient(135deg, #e2e8f0, #cbd5e1);
    border-radius: 12px;
    height: 320px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    font-size: 16px;
}

/* 服务项目 */
.services-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.service-card {
    padding: 32px 24px;
    background: #fff;
    border: 1px solid #e2e8f0;
    border-radius: 12px;
    text-align: center;
    transition: transform 0.3s, box-shadow 0.3s;
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(37,99,235,0.12);
}

.service-icon {
    font-size: 36px;
    margin-bottom: 16px;
    color: #2563eb;
}

.service-card h3 {
    font-size: 18px;
    margin-bottom: 10px;
    color: #1e293b;
}

.service-card p {
    font-size: 14px;
    color: #64748b;
    line-height: 1.7;
}

/* 产品中心 */
.products { background: #f8fafc; }

.products-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.product-card {
    position: relative;
    padding: 32px;
    background: #fff;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.06);
    transition: box-shadow 0.3s;
}

.product-card:hover {
    box-shadow: 0 8px 24px rgba(0,0,0,0.1);
}

.product-tag {
    position: absolute;
    top: 16px;
    right: 16px;
    background: #ef4444;
    color: #fff;
    font-size: 12px;
    padding: 2px 10px;
    border-radius: 20px;
}

.product-card h3 {
    font-size: 20px;
    margin-bottom: 12px;
    color: #1e293b;
}

.product-card p {
    font-size: 14px;
    color: #64748b;
    margin-bottom: 20px;
}

.product-link {
    color: #2563eb;
    font-size: 14px;
    font-weight: 500;
}

.product-link:hover { text-decoration: underline; }

/* 联系我们 */
.contact-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
}

.contact-item {
    margin-bottom: 24px;
}

.contact-item strong {
    display: block;
    font-size: 14px;
    color: #94a3b8;
    margin-bottom: 6px;
}

.contact-item p {
    font-size: 16px;
    color: #1e293b;
}

.contact-item a { color: #2563eb; }

.contact-form .form-group {
    margin-bottom: 16px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    font-size: 15px;
    font-family: inherit;
    transition: border-color 0.3s;
    outline: none;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: #2563eb;
}

.contact-form textarea { resize: vertical; }

/* 页脚 */
.footer {
    background: #1e293b;
    color: #94a3b8;
    text-align: center;
    padding: 32px 20px;
    font-size: 14px;
}

.footer p { margin-bottom: 6px; }
.footer a { color: #94a3b8; }
.footer a:hover { color: #fff; }

/* 返回顶部 */
.back-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    background: #2563eb;
    color: #fff;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s;
    z-index: 999;
    box-shadow: 0 4px 12px rgba(37,99,235,0.4);
}

.back-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-top:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}

/* 响应式 */
@media (max-width: 992px) {
    .services-grid { grid-template-columns: repeat(2, 1fr); }
    .about-grid { grid-template-columns: 1fr; }
    .about-stats { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    .hero-title { font-size: 32px; }
    .hero-subtitle { font-size: 16px; }

    .nav-toggle { display: flex; }

    .nav {
        position: fixed;
        top: 64px;
        left: 0;
        right: 0;
        background: #fff;
        box-shadow: 0 4px 12px rgba(0,0,0,0.1);
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s;
    }

    .nav.open { max-height: 300px; }

    .nav ul {
        flex-direction: column;
        gap: 0;
        padding: 12px 0;
    }

    .nav-link {
        display: block;
        padding: 12px 24px;
        color: #475569 !important;
    }

    .products-grid { grid-template-columns: 1fr; }
    .contact-grid { grid-template-columns: 1fr; }
    .services-grid { grid-template-columns: 1fr; }
}