:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1d4ed8;
    --color-accent: #60a5fa;
    --color-surface: #f8fafc;
    --color-text: #0f172a;
    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;
    --radius-sm: 3px;
    --radius-md: 10px;
    --radius-lg: 18px;
    --radius-xl: 24px;
    --shadow-sm: 0 1px 0 rgba(15, 23, 42, .06), 0 10px 22px rgba(2, 6, 23, .06);
    --shadow-md: 0 2px 0 rgba(15, 23, 42, .05), 0 18px 40px rgba(2, 6, 23, .10), 0 2px 10px rgba(59, 130, 246, .14);
    --shadow-lg: 0 3px 0 rgba(15, 23, 42, .04), 0 30px 70px rgba(2, 6, 23, .14), 0 6px 24px rgba(59, 130, 246, .18);
    --space-section: 3.5rem;
    --space-card: 1.5rem;
    --space-gap: 1.2rem;
    --transition: 420ms cubic-bezier(0.16, 1, 0.3, 1);
    --heading-weight: 650;
    --body-line-height: 1.7;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: radial-gradient(1200px 600px at 20% 0%, rgba(59,130,246,.10), transparent 60%), radial-gradient(900px 480px at 90% 10%, rgba(96,165,250,.10), transparent 55%), linear-gradient(180deg, #0b1220 0%, #0f172a 70%, #0b1220 100%); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); }
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(255,255,255,.08), 0 18px 50px rgba(0,0,0,.35), 0 0 0 1px rgba(148,163,184,.18), 0 10px 28px rgba(59,130,246,.14); padding: var(--space-card); transition: var(--transition); background: linear-gradient(180deg, rgba(248,250,252,.96), rgba(226,232,240,.92)); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); box-shadow: 0 10px 26px rgba(59,130,246,.22), 0 0 0 1px rgba(59,130,246,.20); }
a:not([class]) { color: #93c5fd; transition: var(--transition); text-shadow: 0 1px 0 rgba(2,6,23,.35); }

.card { border-left: 4px solid #60a5fa; }

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

/* news: masonry-2 */
/* 两列瀑布流 */
                .news-grid { column-count: 2; column-gap: var(--space-gap); }
                .news-grid .card { break-inside: avoid; margin-bottom: var(--space-gap); background: linear-gradient(180deg, rgba(248,250,252,.98), rgba(226,232,240,.90)); box-shadow: 0 1px 0 rgba(255,255,255,.09), 0 16px 42px rgba(0,0,0,.30), 0 0 0 1px rgba(148,163,184,.18), 0 10px 26px rgba(59,130,246,.16); }

/* features: horizontal */
/* 水平滚动 */
                .feature-list { display: flex; gap: var(--space-gap); overflow-x: auto; scroll-snap-type: x mandatory; padding: 6px 4px; }
                .feature-list > * { flex: 0 0 300px; scroll-snap-align: start; }

/* hero: split */
/* 左文右图 */
                .hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: center; }
.hero, [class*="hero"], section:first-of-type { background: radial-gradient(1100px 520px at 10% 20%, rgba(59,130,246,.35), transparent 58%), radial-gradient(900px 420px at 90% 0%, rgba(96,165,250,.28), transparent 55%), linear-gradient(135deg, #0b1220 0%, #0f172a 45%, #0b1220 100%); }

/* 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,
.testimonial-list .card { background: linear-gradient(180deg, rgba(248,250,252,.96), rgba(226,232,240,.90)); box-shadow: 0 1px 0 rgba(255,255,255,.08), 0 22px 60px rgba(0,0,0,.28), 0 0 0 1px rgba(148,163,184,.16), 0 12px 30px rgba(59,130,246,.12); }

/* partners: grid-4 */
.partner-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: calc(var(--space-gap) * 1.5); align-items: center; }
.partner-grid .card,
.partner-grid [class*="card"] { background: linear-gradient(180deg, rgba(248,250,252,.96), rgba(226,232,240,.90)); box-shadow: 0 1px 0 rgba(255,255,255,.07), 0 14px 36px rgba(0,0,0,.26), 0 0 0 1px rgba(148,163,184,.14), 0 10px 24px rgba(59,130,246,.10); }

/* faq: single-column */
.faq-list { max-width: 800px; margin: 0 auto; }

/* stats: inline */
/* 水平排列 */
                .stats-grid { display: flex; justify-content: center; gap: 3rem; }
.stats-grid .card,
.stats-grid [class*="card"] { background: linear-gradient(180deg, rgba(248,250,252,.95), rgba(226,232,240,.88)); box-shadow: 0 1px 0 rgba(255,255,255,.07), 0 18px 46px rgba(0,0,0,.26), 0 0 0 1px rgba(148,163,184,.14); }

/* cta: centered */
.cta-inner { text-align: center; max-width: 700px; margin: 0 auto; }
.cta-inner .card,
.cta-inner [class*="card"] { background: linear-gradient(180deg, rgba(248,250,252,.98), rgba(226,232,240,.90)); box-shadow: 0 1px 0 rgba(255,255,255,.09), 0 26px 70px rgba(0,0,0,.28), 0 0 0 1px rgba(148,163,184,.18), 0 12px 32px rgba(59,130,246,.18); }

/* 条件性装饰 */
a:not([class]):hover { color: #93c5fd; text-shadow: 0 0 22px rgba(59,130,246,.35), 0 1px 0 rgba(2,6,23,.35); }
a:not([class]):focus-visible { outline: 3px solid rgba(59,130,246,.35); outline-offset: 3px; border-radius: 10px; }

/* 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: 2.2rem; --space-card: 1.05rem; --space-gap: 0.95rem; }
    .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; }
}