/* ========== Reset & Base ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei",
                 "Segoe UI", "Helvetica Neue", Arial, sans-serif;
    font-size: 15px;
    line-height: 1.7;
    color: #0f172a;
    background: #ffffff;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    text-rendering: optimizeLegibility;
}
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }

/* ========== Variables ========== */
:root {
    --color-text: #0f172a;
    --color-text-sub: #475569;
    --color-text-muted: #94a3b8;
    --color-border: #e2e8f0;
    --color-border-strong: #cbd5e1;
    --color-bg: #ffffff;
    --color-bg-soft: #f8fafc;
    --color-bg-dark: #0f172a;
    --color-accent: #1e3a5f;
    --color-accent-hover: #2a4f7c;
    --max-width: 1180px;
    --gutter: 24px;
}

/* ========== Layout ========== */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--gutter);
}

/* ========== Navbar ========== */
.nav {
    border-bottom: 1px solid var(--color-border);
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: saturate(180%) blur(8px);
    position: sticky;
    top: 0;
    z-index: 50;
}
.nav-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 18px var(--gutter);
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.nav-brand {
    font-size: 18px;
    font-weight: 600;
    letter-spacing: 1px;
    color: var(--color-text);
}
.nav-brand .brand-en {
    font-size: 11px;
    font-weight: 500;
    letter-spacing: 2.5px;
    color: var(--color-text-muted);
    margin-left: 8px;
    text-transform: uppercase;
}
.nav-links {
    display: flex;
    gap: 32px;
    list-style: none;
}
.nav-links a {
    font-size: 14px;
    color: var(--color-text-sub);
    transition: color 0.15s;
    padding: 6px 0;
    border-bottom: 2px solid transparent;
}
.nav-links a:hover, .nav-links a.active {
    color: var(--color-text);
    border-bottom-color: var(--color-accent);
}

@media (max-width: 720px) {
    .nav-inner { padding: 14px 20px; }
    .nav-brand { font-size: 16px; }
    .nav-brand .brand-en { display: none; }
    .nav-links { gap: 18px; }
    .nav-links a { font-size: 13px; }
}

/* ========== Hero ========== */
.hero {
    padding: 100px 0 80px;
    border-bottom: 1px solid var(--color-border);
    background: linear-gradient(180deg, #fafbfd 0%, #ffffff 100%);
}
.hero h1 {
    font-size: 44px;
    line-height: 1.2;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin-bottom: 22px;
    color: var(--color-text);
}
.hero .lead {
    font-size: 18px;
    line-height: 1.7;
    color: var(--color-text-sub);
    max-width: 680px;
}
.hero .tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 500;
    letter-spacing: 1.5px;
    color: var(--color-accent);
    background: rgba(30, 58, 95, 0.08);
    padding: 6px 14px;
    border-radius: 100px;
    margin-bottom: 28px;
    text-transform: uppercase;
}
@media (max-width: 720px) {
    .hero { padding: 60px 0 50px; }
    .hero h1 { font-size: 30px; }
    .hero .lead { font-size: 16px; }
}

/* ========== Section ========== */
.section {
    padding: 80px 0;
    border-bottom: 1px solid var(--color-border);
}
.section:last-of-type {
    border-bottom: none;
}
.section-label {
    font-size: 12px;
    letter-spacing: 2px;
    color: var(--color-accent);
    text-transform: uppercase;
    font-weight: 600;
    margin-bottom: 16px;
}
.section h2 {
    font-size: 32px;
    line-height: 1.3;
    font-weight: 700;
    letter-spacing: -0.3px;
    margin-bottom: 24px;
    color: var(--color-text);
}
.section .section-lead {
    font-size: 17px;
    line-height: 1.7;
    color: var(--color-text-sub);
    max-width: 720px;
    margin-bottom: 40px;
}
@media (max-width: 720px) {
    .section { padding: 50px 0; }
    .section h2 { font-size: 24px; }
    .section .section-lead { font-size: 15px; }
}

/* ========== Cards Grid ========== */
.grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-top: 32px;
}
.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
    margin-top: 32px;
}
.card {
    padding: 32px 28px;
    border: 1px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-bg);
    transition: border-color 0.15s, transform 0.15s;
}
.card:hover {
    border-color: var(--color-border-strong);
    transform: translateY(-2px);
}
.card-num {
    font-size: 13px;
    font-weight: 600;
    color: var(--color-accent);
    margin-bottom: 12px;
    letter-spacing: 1px;
}
.card h3 {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--color-text);
}
.card p {
    font-size: 14px;
    line-height: 1.65;
    color: var(--color-text-sub);
}
@media (max-width: 920px) {
    .grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 620px) {
    .grid, .grid-2 { grid-template-columns: 1fr; }
}

/* ========== Article (for privacy/terms/about) ========== */
.article {
    max-width: 760px;
    padding: 80px 0 100px;
}
.article h1 {
    font-size: 36px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 12px;
    letter-spacing: -0.3px;
}
.article .updated {
    font-size: 13px;
    color: var(--color-text-muted);
    margin-bottom: 40px;
}
.article h2 {
    font-size: 22px;
    font-weight: 600;
    margin-top: 48px;
    margin-bottom: 16px;
    color: var(--color-text);
}
.article h3 {
    font-size: 17px;
    font-weight: 600;
    margin-top: 28px;
    margin-bottom: 12px;
    color: var(--color-text);
}
.article p, .article li {
    font-size: 15px;
    line-height: 1.85;
    color: var(--color-text-sub);
    margin-bottom: 14px;
}
.article ul, .article ol {
    padding-left: 24px;
    margin-bottom: 18px;
}
.article li { margin-bottom: 8px; }
.article strong { color: var(--color-text); }
@media (max-width: 720px) {
    .article { padding: 50px 0 60px; }
    .article h1 { font-size: 26px; }
    .article h2 { font-size: 19px; }
}

/* ========== About / Contact Info ========== */
.entity-box {
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: 32px;
    background: var(--color-bg-soft);
}
.entity-box .entity-name {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 4px;
    color: var(--color-text);
}
.entity-box .entity-name-en {
    font-size: 12px;
    color: var(--color-text-muted);
    letter-spacing: 0.8px;
    margin-bottom: 18px;
    text-transform: uppercase;
}
.entity-box .entity-row {
    display: flex;
    margin-bottom: 12px;
    font-size: 14px;
    line-height: 1.6;
}
.entity-box .entity-row .label {
    width: 90px;
    color: var(--color-text-muted);
    flex-shrink: 0;
}
.entity-box .entity-row .value {
    color: var(--color-text-sub);
    flex: 1;
}

/* ========== Footer ========== */
.footer {
    background: var(--color-bg-dark);
    color: #cbd5e1;
    padding: 60px 0 28px;
}
.footer-inner {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--gutter);
}
.footer-grid {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: 60px;
    margin-bottom: 40px;
}
.footer-col h4 {
    font-size: 12px;
    font-weight: 600;
    letter-spacing: 2px;
    color: #94a3b8;
    text-transform: uppercase;
    margin-bottom: 18px;
}
.footer-col .brand-name {
    font-size: 17px;
    font-weight: 600;
    color: #f1f5f9;
    margin-bottom: 6px;
    letter-spacing: 1px;
}
.footer-col .brand-desc {
    font-size: 13px;
    color: #94a3b8;
    line-height: 1.7;
    margin-bottom: 18px;
}
.footer-col ul { list-style: none; }
.footer-col li { margin-bottom: 10px; }
.footer-col a {
    font-size: 13px;
    color: #cbd5e1;
    transition: color 0.15s;
}
.footer-col a:hover { color: #fff; }
.footer-col p {
    font-size: 13px;
    color: #94a3b8;
    line-height: 1.7;
    margin-bottom: 6px;
}

.footer-meta {
    border-top: 1px solid #1e293b;
    padding-top: 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
}
.footer-meta .entities {
    font-size: 12px;
    color: #94a3b8;
    line-height: 1.8;
}
.footer-meta .entities strong {
    color: #cbd5e1;
}
.footer-meta .beian {
    font-size: 12px;
    color: #94a3b8;
}
.footer-meta .beian a {
    color: #94a3b8;
    transition: color 0.15s;
}
.footer-meta .beian a:hover { color: #cbd5e1; }
.footer-copyright {
    margin-top: 16px;
    font-size: 11px;
    color: #64748b;
    text-align: center;
}

@media (max-width: 720px) {
    .footer-grid { grid-template-columns: 1fr; gap: 32px; }
    .footer-meta { flex-direction: column; align-items: flex-start; }
}