:root {
    --color-primary: #334155;
    --color-primary-dark: #1e293b;
    --color-accent: #3b82f6;
    --color-surface: #f8fafc;
    --color-text: #0f172a;
    --rgb-primary: 51,65,85;
    --rgb-accent: 59,130,246;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 18px;
    --shadow-sm: 0 1px 2px rgba(15,23,42,.06), 0 1px 3px rgba(15,23,42,.1);
    --shadow-md: 0 2px 4px rgba(15,23,42,.06), 0 4px 12px rgba(51,65,85,.1), 0 1px 2px rgba(59,130,246,.08);
    --shadow-lg: 0 4px 8px rgba(15,23,42,.08), 0 12px 28px rgba(51,65,85,.14), 0 2px 6px rgba(59,130,246,.1);
    --space-section: 4.5rem;
    --space-card: 1.75rem;
    --space-gap: 1.25rem;
    --transition: 0.5s cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 600;
    --body-line-height: 1.65;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: linear-gradient(180deg, #f8fafc 0%, #f1f5f9 50%, #e2e8f0 100%); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); background: linear-gradient(135deg, #1e293b 0%, #334155 60%, #3b82f6 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); background: linear-gradient(180deg, rgba(248,250,252,0) 0%, rgba(226,232,240,.35) 100%); }
.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%); }
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); background: linear-gradient(135deg, #3b82f6 0%, #2563eb 50%, #1d4ed8 100%); color: #ffffff; box-shadow: 0 2px 6px rgba(59,130,246,.28), 0 8px 20px rgba(37,99,235,.18); }
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: centered */
/* 居中大卡片 */
                .feature-list { display: flex; flex-direction: column; align-items: center; gap: calc(var(--space-gap) * 2); max-width: 720px; margin: 0 auto; }

/* 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 45%, #1d4ed8 100%); }
                .hero-content { position: relative; z-index: 1; }

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

/* 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-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, #eff6ff 0%, #dbeafe 45%, #bfdbfe 100%); border-radius: var(--radius-xl); padding: 3rem; text-align: center; box-shadow: var(--shadow-lg); border: 1px solid rgba(59,130,246,.18); }

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

/* 条件性装饰 */
a:not([class]):hover { color: var(--color-accent); }
.card { border: 1px solid rgba(var(--rgb-primary), .08); }
header, .header, .navbar { box-shadow: 0 2px 8px rgba(30,41,59,.08), 0 1px 3px rgba(59,130,246,.1); background: linear-gradient(180deg, #ffffff 0%, #f8fafc 100%); }

/* 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; }
}