/* ===== 基础重置 ===== */
* { box-sizing: border-box; }
html { font-size: var(--fs-base, 16px); }
body {
    margin: 0;
    font-family: var(--font-family);
    line-height: var(--lh, 1.7);
    color: var(--c-text, #0f172a);
    background: var(--c-bg, #fff);
    -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; height: auto; display: block; }
a { color: var(--c-primary, #1d4ed8); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ===== 布局容器 ===== */
.container {
    width: 100%;
    max-width: var(--container, 1200px);
    margin: 0 auto;
    padding: 0 20px;
}
.section { padding: var(--spacing, 64px) 0; }
.section-alt { background: var(--c-surface, #f8fafc); }

/* ===== 标题 ===== */
h1, h2, h3, h4 { font-weight: var(--fw-heading, 700); line-height: 1.25; margin: 0 0 .5em; }
h1 { font-size: clamp(28px, 4vw, 44px); }
h2.section-title { font-size: clamp(22px, 3vw, 32px); text-align: center; margin-bottom: 1.2em; }
h3 { font-size: 1.25rem; }

/* ===== 按钮 ===== */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: var(--radius, 10px);
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    border: 1px solid transparent;
    transition: opacity .2s ease;
}
.btn:hover { text-decoration: none; opacity: .9; }
.btn-primary { background: var(--c-primary, #1d4ed8); color: #fff; }
.btn-accent { background: var(--c-accent, #f59e0b); color: #fff; }

/* ===== 顶栏导航 ===== */
.site-header { position: sticky; top: 0; z-index: 50; background: rgba(255,255,255,.92); backdrop-filter: blur(8px); border-bottom: 1px solid var(--c-border); }
.nav-inner { display: flex; align-items: center; justify-content: space-between; height: var(--header-h, 64px); }
.brand { font-size: 1.25rem; font-weight: 700; color: var(--c-secondary); }
.nav-links { display: flex; gap: 24px; list-style: none; margin: 0; padding: 0; }
.nav-links a { color: var(--c-text); font-weight: 500; }
.nav-links a:hover { color: var(--c-primary); }

/* ===== Hero ===== */
.hero {
    background-size: cover; background-position: center; color: #fff;
    padding: calc(var(--spacing) * 1.4) 0; text-align: center;
}
.hero-inner { max-width: 760px; margin: 0 auto; }
.hero h1 { color: #fff; }
.hero-sub { font-size: 1.2rem; opacity: .92; margin: 1em 0 1.8em; }

/* ===== 网格与卡片 ===== */
.grid { display: grid; gap: 24px; }
.card {
    background: #fff; border: 1px solid var(--c-border); border-radius: var(--radius);
    overflow: hidden; transition: box-shadow .2s ease, transform .2s ease;
}
.card:hover { box-shadow: 0 8px 24px rgba(15,23,42,.12); transform: translateY(-3px); }
.card-img { width: 100%; aspect-ratio: 3/2; object-fit: cover; }
.card-body { padding: 18px 20px; }
.card-title { margin: 0 0 .4em; font-size: 1.1rem; }
.card-text { color: var(--c-muted); margin: 0; }

/* ===== 资讯 / 文章 ===== */
.grid-news { gap: 18px; }
.news-item { background: #fff; border: 1px solid var(--c-border); border-radius: var(--radius); padding: 20px; }
.news-title { margin: 0 0 .4em; font-size: 1.1rem; }
.news-summary { color: var(--c-muted); margin: 0 0 .6em; }
.news-date, .news-keywords { color: var(--c-muted); font-size: .85rem; }

/* ===== 关于 ===== */
.about { max-width: 860px; margin: 0 auto; }
.about-title { margin-top: 0; }

/* ===== FAQ ===== */
.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item { background: #fff; border: 1px solid var(--c-border); border-radius: var(--radius); padding: 0 20px; margin-bottom: 12px; }
.faq-item summary { cursor: pointer; padding: 16px 0; font-weight: 600; }
.faq-answer { padding: 0 0 16px; color: var(--c-text); }

/* ===== 联系 ===== */
.contact-grid { display: grid; grid-template-columns: 1.4fr 1fr; gap: 32px; }
.contact-form { display: flex; flex-direction: column; gap: 14px; }
.contact-form label { display: flex; flex-direction: column; gap: 6px; font-weight: 600; color: var(--c-muted); }
.contact-form input, .contact-form textarea {
    padding: 12px 14px; border: 1px solid var(--c-border); border-radius: var(--radius);
    font: inherit; color: var(--c-text); background: #fff;
}
.contact-form textarea { min-height: 120px; resize: vertical; }
.contact-info p { margin: .4em 0; color: var(--c-muted); }

/* ===== CTA ===== */
.cta { background: var(--c-primary); color: #fff; text-align: center; }
.cta-inner .btn-accent { font-size: 1.1rem; padding: 14px 40px; }

/* ===== 页脚 ===== */
.footer { background: var(--c-secondary); color: #cbd5e1; padding: 48px 0 28px; }
.footer-cols { display: flex; flex-wrap: wrap; gap: 40px; margin-bottom: 28px; }
.footer-col h4 { color: #fff; margin-bottom: 12px; }
.footer-col ul { list-style: none; padding: 0; margin: 0; }
.footer-col li { margin-bottom: 8px; }
.footer-col a { color: #cbd5e1; }
.footer-meta { border-top: 1px solid rgba(255,255,255,.12); padding-top: 18px; display: flex; flex-wrap: wrap; gap: 18px; }
.footer-meta .copyright { width: 100%; margin: 8px 0 0; color: #94a3b8; }

/* ===== 响应式（单 URL 适配 PC + H5） ===== */
@media (max-width: 768px) {
    .container { padding: 0 14px; }
    .grid { grid-template-columns: 1fr !important; }
    .grid-news { grid-template-columns: 1fr !important; }
    .nav-links { gap: 14px; font-size: .9rem; }
    .contact-grid { grid-template-columns: 1fr; }
    .footer-cols { gap: 24px; }
    .hero { padding: 48px 0; }
}