:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1d4ed8;
    --color-accent: #60a5fa;
    --color-surface: #f1f5f9;
    --color-text: #1e293b;
    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --shadow-sm: 0 2px 4px rgba(15,23,42,.04), 0 6px 12px -2px rgba(15,23,42,.06);
    --shadow-md: 0 4px 8px rgba(15,23,42,.05), 0 20px 40px -10px rgba(15,23,42,.12);
    --shadow-lg: 0 8px 16px rgba(15,23,42,.06), 0 32px 64px -12px rgba(15,23,42,.18);
    --space-section: 3rem;
    --space-card: 1.25rem;
    --space-gap: 1rem;
    --transition: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
    --heading-weight: 700;
    --body-line-height: 1.7;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background-color: #f8fafc; }
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: featured-top */
/* 首篇横跨全宽 */
                .news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); }
                .news-grid > *:first-child { grid-column: span 3; }

/* features: grid-2 */
.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: calc(var(--space-gap) * 1.5); }

/* hero: overlay */
/* 全屏背景+文字覆盖 */
                .hero { position: relative; min-height: 70vh; display: flex; align-items: center; background: linear-gradient(135deg, #1e293b 0%, #334155 100%); }
                .hero-content { position: relative; z-index: 1; }

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

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

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

/* stats: grid-4 */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-gap); text-align: center; }

/* cta: card-style */
.cta-inner { background: linear-gradient(135deg, #f1f5f9 0%, #e2e8f0 100%); border-radius: var(--radius-xl); padding: 3rem; text-align: center; box-shadow: var(--shadow-md); }

/* Page Layout: wide */
/* 超宽 */
            .page-main { max-width: 1400px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover, [class*="card"]:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.card { border: 1px solid rgba(59,130,246,.10); background-color: #ffffff; }
header, .header, .navbar { box-shadow: 0 2px 6px rgba(15,23,42,.05), 0 8px 16px -4px rgba(15,23,42,.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: 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; }
}