:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1e40af;
    --color-accent: #60a5fa;
    --color-surface: #ffffff;
    --color-text: #0f172a;
    --rgb-primary: 37,99,235;
    --rgb-accent: 96,165,250;
    --radius-sm: 3px;
    --radius-md: 10px;
    --radius-lg: 18px;
    --radius-xl: 26px;
    --shadow-sm:
        0 1px 0 rgba(15, 23, 42, .06),
        0 6px 18px rgba(2, 6, 23, .08);
    --shadow-md:
        0 1px 0 rgba(15, 23, 42, .06),
        0 10px 26px rgba(2, 6, 23, .12),
        0 0 0 1px rgba(148, 163, 184, .22) inset;
    --shadow-lg:
        0 2px 0 rgba(15, 23, 42, .07),
        0 22px 54px rgba(2, 6, 23, .18),
        0 0 0 1px rgba(148, 163, 184, .28) inset;
    --space-section: 3.75rem;
    --space-card: 2.15rem;
    --space-gap: 2.2rem;
    --transition: 520ms cubic-bezier(0.16, 1, 0.3, 1);
    --heading-weight: 650;
    --body-line-height: 1.65;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: linear-gradient(180deg, #0b1220 0%, #0f172a 55%, #0b1220 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-xl);
    box-shadow:
        0 1px 0 rgba(255,255,255,.06),
        0 18px 48px rgba(2, 6, 23, .28),
        0 0 0 1px rgba(148, 163, 184, .18) inset;
    padding: var(--space-card);
    transition: box-shadow var(--transition), transform var(--transition), background-color var(--transition), border-color var(--transition), filter var(--transition);
    background: linear-gradient(180deg, rgba(255,255,255,.98) 0%, rgba(248,250,252,.96) 100%);
    filter: saturate(1.02);
}
.btn, button[class*="btn"], a[class*="btn"] { border-radius: var(--radius-md); transition: var(--transition); }
a:not([class]) { color: var(--color-accent); transition: var(--transition); text-shadow: 0 1px 0 rgba(2, 6, 23, .18); }

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

/* news: grid-4 */
/* 四列紧凑网格 */
                .news-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: calc(var(--space-gap) * 0.6); }

/* features: grid-2 */
.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: calc(var(--space-gap) * 1.25); }

/* hero: split */
/* 左文右图 */
                .hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: center; }

/* testimonials: grid-3 */
.testimonial-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); }

/* partners: centered */
.partner-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 2rem; }

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

/* stats: big-number */
/* 大数字居中 */
                .stats-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 2rem; }
                .stats-grid .stat-value { font-size: 3rem; text-shadow: 0 10px 30px rgba(2, 6, 23, .35); }

/* 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 */
.card:hover, [class*="card"]:hover {
    transform: translateY(-6px);
    box-shadow:
        0 2px 0 rgba(255,255,255,.07),
        0 28px 74px rgba(2, 6, 23, .35),
        0 0 0 1px rgba(59, 130, 246, .38) inset,
        0 0 0 6px rgba(59, 130, 246, .10);
    background: linear-gradient(180deg, rgba(255,255,255,1) 0%, rgba(241,245,249,.98) 100%);
    filter: saturate(1.05) contrast(1.02);
}
a:not([class]):hover { color: #93c5fd; text-shadow: 0 0 18px rgba(59, 130, 246, .35); }
.hero, [class*="hero"], section:first-of-type {
    background:
        radial-gradient(900px 360px at 15% 10%, rgba(59, 130, 246, .35) 0%, rgba(59, 130, 246, 0) 60%),
        radial-gradient(780px 340px at 85% 20%, rgba(96, 165, 250, .22) 0%, rgba(96, 165, 250, 0) 65%),
        linear-gradient(135deg, #1e293b, #334155);
    box-shadow: 0 18px 60px rgba(2, 6, 23, .25) inset;
    border-radius: var(--radius-xl);
}
.card { border-left: 4px solid var(--color-accent); }
header, .header, .navbar {
    box-shadow:
        0 1px 0 rgba(255,255,255,.06),
        0 12px 30px rgba(2, 6, 23, .25);
    background: linear-gradient(180deg, rgba(15, 23, 42, .86) 0%, rgba(17, 24, 39, .76) 100%);
    border-bottom: 1px solid rgba(148, 163, 184, .18);
}

/* 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: 2.2rem; --space-card: 1.35rem; --space-gap: 1.05rem; }
    .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; }
}