:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1e40af;
    --color-accent: #60a5fa;
    --color-surface: #f8fafc;
    --color-text: #1e293b;
    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --shadow-sm: 0 1px 2px rgba(0,0,0,.05), 0 1px 3px rgba(59,130,246,.08);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(59,130,246,0.05), 0 0 0 1px rgba(59,130,246,.03);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(59,130,246,0.1), 0 0 0 1px rgba(59,130,246,.05);
    --space-section: 3rem;
    --space-card: 1.25rem;
    --space-gap: 1rem;
    --transition: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
    --heading-weight: 600;
    --body-line-height: 1.65;
}

body { color: var(--color-text); line-height: var(--body-line-height); background: linear-gradient(180deg, #f1f5f9 0%, #e2e8f0 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: var(--shadow-md); padding: var(--space-card); transition: var(--transition); background: linear-gradient(135deg, #ffffff, #f8fafc); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); background: linear-gradient(135deg, var(--color-primary), var(--color-accent)); color: #fff; border: none; box-shadow: 0 2px 4px rgba(59,130,246,0.3); }
a:not([class]) { color: var(--color-primary); transition: var(--transition); text-decoration: none; border-bottom: 1px solid transparent; background-image: linear-gradient(135deg, var(--color-primary), var(--color-accent)); background-repeat: no-repeat; background-size: 100% 2px; background-position: 0 100%; }

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

/* news: featured-left */
.news-grid { display: grid; grid-template-columns: 2fr 1fr; grid-template-rows: auto auto; gap: var(--space-gap); }
.news-grid > *:first-child { grid-row: span 2; }

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

/* hero: minimal */
.hero { padding: 2rem 0; background: linear-gradient(135deg, #1e293b, #334155); color: #f8fafc; } .hero-content { max-width: 560px; }

/* testimonials: masonry */
.testimonial-list { column-count: 2; column-gap: var(--space-gap); }
.testimonial-list > * { break-inside: avoid; margin-bottom: var(--space-gap); }

/* partners: scroll */
.partner-grid { display: flex; gap: 2rem; overflow: hidden; animation: partnerScroll 20s linear infinite; }
@keyframes partnerScroll { 0% { transform: translateX(0); } 100% { transform: translateX(-50%); } }

/* faq: with-sidebar */
.faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 2rem; }

/* stats: grid-3 */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); text-align: center; }

/* cta: card-style */
.cta-inner { background: linear-gradient(135deg, #3b82f6, #60a5fa); border-radius: var(--radius-xl); padding: 3rem; text-align: center; color: #fff; }

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

/* 条件性装饰 */
a:not([class]):hover { color: var(--color-accent); border-bottom-color: var(--color-accent); }
.card { border: 1px solid transparent; border-image: linear-gradient(135deg, #3b82f6, #60a5fa) 1; border-image-slice: 1; }
header, .header, .navbar { background: linear-gradient(135deg, #1e293b, #334155); box-shadow: 0 2px 8px rgba(0,0,0,0.2); color: #f8fafc; }

/* 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; }
}