:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1e40af;
    --color-accent: #60a5fa;
    --color-surface: #f1f5f9;
    --color-text: #1e293b;
    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;
    --radius-sm: 3px;
    --radius-md: 6px;
    --radius-lg: 10px;
    --radius-xl: 14px;
    --shadow-sm: 0 1px 3px rgba(30,41,59,.08), 0 1px 2px rgba(30,41,59,.06);
    --shadow-md: 0 4px 12px rgba(30,41,59,.10), 0 2px 4px rgba(30,41,59,.06);
    --shadow-lg: 0 10px 28px rgba(30,41,59,.14), 0 4px 10px rgba(30,41,59,.08);
    --space-section: 4rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;
    --transition: 0.5s cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 700;
    --body-line-height: 1.75;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: linear-gradient(160deg, #f8fafc 0%, #e2e8f0 50%, #f1f5f9 100%); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); background: linear-gradient(135deg, #1e293b 0%, #334155 60%, #1e40af 100%); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
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); background: linear-gradient(145deg, #ffffff 0%, #f8fafc 55%, #eff6ff 100%); border: 1px solid rgba(59,130,246,.12); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); background: linear-gradient(135deg, #3b82f6 0%, #2563eb 50%, #1e40af 100%); color: #ffffff; border: 1px solid rgba(59,130,246,.3); box-shadow: 0 2px 8px rgba(59,130,246,.25), 0 1px 3px rgba(30,41,59,.10); }
a:not([class]) { color: var(--color-primary); transition: var(--transition); }

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

/* news: grid-3 */
/* 三列等宽网格 */
                .news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); }

/* features: grid-4 */
.feature-list { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-gap); }

/* hero: centered */
.hero-content { text-align: center; max-width: 800px; margin: 0 auto; background: radial-gradient(ellipse at 50% 0%, rgba(59,130,246,.08) 0%, rgba(96,165,250,.04) 40%, transparent 70%); border-radius: var(--radius-xl); }

/* testimonials: carousel */
/* 单条轮播 */
                .testimonial-list { display: flex; overflow: hidden; } 
                .testimonial-list > * { flex: 0 0 100%; }

/* partners: grid-4 */
.partner-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: calc(var(--space-gap) * 1.5); align-items: center; }

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

/* stats: grid-3 */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); text-align: center; background: linear-gradient(180deg, rgba(59,130,246,.06) 0%, rgba(96,165,250,.03) 50%, transparent 100%); border-radius: var(--radius-lg); }

/* cta: centered */
.cta-inner { text-align: center; max-width: 700px; margin: 0 auto; background: linear-gradient(135deg, rgba(59,130,246,.07) 0%, rgba(30,64,175,.04) 50%, rgba(96,165,250,.06) 100%); border-radius: var(--radius-xl); }

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

/* 条件性装饰 */
header, .header, .navbar { box-shadow: 0 2px 12px rgba(30,41,59,.10), 0 1px 4px rgba(59,130,246,.08); background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%); border-bottom: 1px solid rgba(59,130,246,.10); }

/* 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: 1rem; --space-gap: 0.75rem; }
    .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; }
}