:root {
    --color-primary: #1f6feb;
    --color-primary-dark: #1450b3;
    --color-accent: #38bdf8;
    --color-surface: #eaf4ff;
    --color-text: #1c2a3a;
    --rgb-primary: 31,111,235;
    --rgb-accent: 56,189,248;
    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 20px;
    --radius-xl: 28px;
    --shadow-sm: 0 1px 3px rgba(31,111,235,.14), 0 0 12px rgba(56,189,248,.10);
    --shadow-md: 0 6px 18px rgba(20,80,179,.16), 0 0 24px rgba(56,189,248,.22);
    --shadow-lg: 0 16px 36px rgba(20,80,179,.20), 0 0 36px rgba(56,189,248,.30);
    --space-section: 4rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;
    --transition: 0.35s cubic-bezier(0.22, 0.61, 0.36, 1);
    --heading-weight: 700;
    --body-line-height: 1.6;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: linear-gradient(180deg, #f6fbff 0%, #eaf4ff 100%); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); color: #16202e; }
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: #ffffff; border: 1px solid rgba(56,189,248,.18); }
.card:hover, [class*="card"]:hover { box-shadow: 0 0 32px rgba(56,189,248,.6), 0 12px 28px rgba(20,80,179,.20); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); box-shadow: 0 0 24px rgba(56,189,248,.35); }
.btn:hover, button[class*="btn"]:hover, a[class*="btn"]:hover { box-shadow: 0 0 32px rgba(56,189,248,.6); }
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: minimal */
.hero { padding: 2rem 0; } .hero-content { max-width: 560px; }

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

/* 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%); } }

/* 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; }

/* cta: split */
.cta-inner { display: grid; grid-template-columns: 1fr auto; align-items: center; gap: 2rem; }

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

/* 条件性装饰 */
header, .header, .navbar { box-shadow: 0 2px 10px rgba(20,80,179,.14), 0 0 18px rgba(56,189,248,.20); background: #252e3a; }

/* 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; }
}