:root {
    --color-primary: #4f46e5;
    --color-primary-dark: #312e81;
    --color-accent: #0d9488;
    --color-surface: #f8fafc;
    --color-text: #1f2937;
    --rgb-primary: 79,70,229;
    --rgb-accent: 13,148,136;
    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 18px;
    --radius-xl: 24px;
    --shadow-sm: 0 1px 2px rgba(15,23,42,0.04), 0 4px 8px -2px rgba(15,23,42,0.05);
    --shadow-md: 0 4px 8px rgba(15,23,42,0.05), 0 12px 24px -8px rgba(15,23,42,0.12);
    --shadow-lg: 0 8px 16px rgba(15,23,42,0.08), 0 20px 40px -10px rgba(15,23,42,0.15);
    --space-section: 2.25rem;
    --space-card: 1.125rem;
    --space-gap: 0.875rem;
    --transition: 0.45s cubic-bezier(0.25, 1, 0.5, 1);
    --heading-weight: 700;
    --body-line-height: 1.75;
}

/* 基础覆盖 */
body { background-color: var(--color-surface); color: var(--color-text); line-height: var(--body-line-height); }
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: var(--shadow-md); padding: var(--space-card); transition: var(--transition); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); }
a:not([class]) { color: var(--color-primary); transition: var(--transition); }

/* ========== 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; }

/* 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; }

/* hero: minimal */
.hero { padding: 2.25rem 0; } .hero-content { max-width: 560px; }

/* testimonials: stacked */
/* 垂直堆叠 */
                .testimonial-list { display: flex; flex-direction: column; gap: var(--space-gap); max-width: 720px; margin: 0 auto; }

/* partners: scroll */
/* 自动滚动 */
                .partner-grid { display: flex; gap: 1.75rem; overflow: hidden; animation: partnerScroll 24s linear infinite; }
                @keyframes partnerScroll { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }

/* faq: two-column */
.faq-list { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-gap); }

/* stats: inline */
/* 水平排列 */
                .stats-grid { display: flex; justify-content: center; gap: 2.5rem; }

/* cta: split */
.cta-inner { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 1.75rem; }

/* Page Layout: full-width */
/* 无侧边栏, 全宽 */
            .page-main { max-width: 1200px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover, [class*="card"]:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-left-color: var(--color-accent); }
a:not([class]):hover { color: var(--color-accent); }
.card { background-color: #ffffff; border-left: 3px solid var(--color-primary); }
header, .header, .navbar { box-shadow: 0 1px 2px rgba(15,23,42,0.04), 0 6px 16px -4px rgba(15,23,42,0.08); }

/* 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: 2.25rem; --space-card: 1.125rem; --space-gap: 0.875rem; }
    .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; }
}