:root {
    --color-primary: #1d4ed8;
    --color-primary-dark: #1e3a8a;
    --color-accent: #38bdf8;
    --color-surface: #f8fafc;
    --color-text: #0f172a;
    --rgb-primary: 29,78,216;
    --rgb-accent: 56,189,248;

    --radius-sm: 2px;
    --radius-md: 3px;
    --radius-lg: 5px;
    --radius-xl: 7px;

    --shadow-sm: 0 0 0 rgba(0,0,0,0);
    --shadow-md: 0 1px 0 rgba(15, 23, 42, 0.06), 0 10px 24px rgba(2, 6, 23, 0.08);
    --shadow-lg: 0 2px 0 rgba(15, 23, 42, 0.08), 0 14px 32px rgba(2, 6, 23, 0.12), 0 0 0 1px rgba(59, 130, 246, 0.08);

    --space-section: 4rem;
    --space-card: 1.15rem;
    --space-gap: 0.95rem;

    --transition: 220ms cubic-bezier(0.2, 0.8, 0.2, 1);
    --heading-weight: 700;
    --body-line-height: 1.75;

    --outline-focus: rgba(56, 189, 248, 0.55);
    --card-bg: #ffffff;
    --card-stroke: rgba(51, 65, 85, 0.18);
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: radial-gradient(900px 500px at 20% -10%, rgba(59, 130, 246, 0.18), rgba(59, 130, 246, 0) 60%), radial-gradient(700px 450px at 95% 0%, rgba(56, 189, 248, 0.14), rgba(56, 189, 248, 0) 55%), linear-gradient(180deg, #0b1220 0%, #0f172a 45%, #0b1220 100%); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); color: rgba(255,255,255,0.92); }
section, .section { padding-top: var(--space-section); padding-bottom: var(--space-section); }
.card, [class*="card"] {
    border-radius: var(--radius-lg);
    box-shadow: 0 1px 0 rgba(2, 6, 23, 0.06), 0 10px 22px rgba(2, 6, 23, 0.14);
    padding: var(--space-card);
    transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition), background-color var(--transition);
    background: linear-gradient(180deg, rgba(255,255,255,0.98) 0%, rgba(248,250,252,0.96) 100%);
    border: 1px solid rgba(148, 163, 184, 0.22);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: background-color var(--transition), color var(--transition), box-shadow var(--transition), border-color var(--transition), transform var(--transition);
    border: 1px solid rgba(56, 189, 248, 0.25);
}
a:not([class]) { color: #60a5fa; transition: color var(--transition), text-shadow var(--transition), opacity var(--transition); }
a:not([class]):hover { color: var(--color-accent); text-shadow: 0 0 18px rgba(56, 189, 248, 0.35); }

.hero, [class*="hero"], section:first-of-type {
    background: radial-gradient(900px 520px at 15% 10%, rgba(56, 189, 248, 0.28), rgba(56, 189, 248, 0) 60%),
                radial-gradient(700px 420px at 85% 20%, rgba(59, 130, 246, 0.26), rgba(59, 130, 246, 0) 55%),
                linear-gradient(135deg, #0b2a6f 0%, #0f172a 45%, #0b1220 100%);
    color: rgba(255,255,255,0.92);
}
section, .section { color: rgba(226, 232, 240, 0.92); }

/* ========== Section Layout Variants ========== */

/* news: list-view */
/* 列表模式 (图左文右) */
                .news-grid { display: flex; flex-direction: column; gap: var(--space-gap); }
                .news-grid .card {
                    display: grid;
                    grid-template-columns: 280px 1fr;
                    border-radius: calc(var(--radius-lg) + 1px);
                    box-shadow: 0 1px 0 rgba(2, 6, 23, 0.06), 0 10px 24px rgba(2, 6, 23, 0.12);
                    border-color: rgba(148, 163, 184, 0.2);
                }

/* features: horizontal */
/* 水平滚动 */
                .feature-list { display: flex; gap: var(--space-gap); overflow-x: auto; scroll-snap-type: x mandatory; }
                .feature-list > * { flex: 0 0 300px; scroll-snap-align: start; }
                .feature-list .card { border-radius: var(--radius-md); border-color: rgba(59, 130, 246, 0.16); box-shadow: 0 1px 0 rgba(2,6,23,0.05), 0 12px 24px rgba(2,6,23,0.10); }

/* hero: centered */
.hero-content { text-align: center; max-width: 800px; margin: 0 auto; }
.hero-content h1, .hero-content h2 { text-shadow: 0 1px 0 rgba(0,0,0,0.35), 0 10px 30px rgba(59, 130, 246, 0.25); }

/* testimonials: masonry */
.testimonial-list { column-count: 2; column-gap: var(--space-gap); }
                .testimonial-list > * { break-inside: avoid; margin-bottom: var(--space-gap); }
                .testimonial-list .card { background: linear-gradient(180deg, rgba(255,255,255,0.98) 0%, rgba(241,245,249,0.96) 100%); border-radius: var(--radius-sm); border-color: rgba(148, 163, 184, 0.18); box-shadow: 0 1px 0 rgba(2,6,23,0.06), 0 10px 18px rgba(2,6,23,0.10); }

/* partners: scroll */
/* 自动滚动 */
                .partner-grid { display: flex; gap: 2rem; overflow: hidden; animation: partnerScroll 20s linear infinite; }
                @keyframes partnerScroll { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }
                .partner-grid .card, .partner-grid [class*="card"] { border-radius: var(--radius-md); border-color: rgba(56, 189, 248, 0.18); box-shadow: 0 1px 0 rgba(2,6,23,0.05), 0 10px 20px rgba(2,6,23,0.10); }

/* faq: two-column */
.faq-list { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-gap); }
.faq-list .card { border-radius: var(--radius-md); border-color: rgba(148, 163, 184, 0.2); box-shadow: 0 1px 0 rgba(2,6,23,0.05), 0 12px 24px rgba(2,6,23,0.10); }

/* stats: big-number */
/* 大数字居中 */
                .stats-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 2rem; }
                .stats-grid .stat-value { font-size: 3rem; color: rgba(255,255,255,0.95); text-shadow: 0 1px 0 rgba(0,0,0,0.35), 0 18px 40px rgba(59, 130, 246, 0.22); }
                .stats-grid .card { border-radius: var(--radius-sm); border-color: rgba(59,130,246,0.20); box-shadow: 0 1px 0 rgba(2,6,23,0.06), 0 14px 26px rgba(2,6,23,0.12); }

/* cta: full-bg */
.cta-section { background: linear-gradient(135deg, rgba(29,78,216,0.98) 0%, rgba(15,23,42,0.96) 55%, rgba(56,189,248,0.92) 100%); color: #ffffff; padding: 4rem 2rem; }
.cta-section .card { border-color: rgba(255,255,255,0.18); box-shadow: 0 2px 0 rgba(0,0,0,0.10), 0 18px 34px rgba(0,0,0,0.25); }
.cta-section a:not([class]) { color: #cfe9ff; }
.cta-section a:not([class]):hover { color: #ffffff; text-shadow: 0 0 22px rgba(255,255,255,0.25); }

/* Page Layout: narrow-centered */
/* 窄版居中 */
            .page-main { max-width: 860px; margin: 0 auto; }

/* Responsive */
@media (max-width: 1024px) {
    .news-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .feature-list { grid-template-columns: repeat(2, 1fr) !important; }
    .partner-grid { grid-template-columns: repeat(3, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .hero-inner { grid-template-columns: 1fr !important; }
}
@media (max-width: 640px) {
    :root { --space-section: 2rem; --space-card: 0.95rem; --space-gap: 0.75rem; --radius-lg: 6px; --transition: 190ms cubic-bezier(0.2, 0.9, 0.2, 1); }
    .news-grid { grid-template-columns: 1fr !important; }
    .feature-list { grid-template-columns: 1fr !important; }
    .faq-list { grid-template-columns: 1fr !important; }
    .testimonial-list { column-count: 1 !important; }
    .partner-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .cta-inner { grid-template-columns: 1fr !important; }
}