:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1d4ed8;
    --color-accent: #60a5fa;
    --color-surface: #f8fafc;
    --color-text: #0f172a;
    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 18px;
    --shadow-sm: 0 1px 0 rgba(15, 23, 42, .06), 0 10px 22px rgba(2, 6, 23, .06);
    --shadow-md: 0 1px 0 rgba(2, 6, 23, .05), 0 10px 30px rgba(2, 6, 23, .10), 0 2px 8px rgba(59, 130, 246, .12);
    --shadow-lg: 0 2px 0 rgba(2, 6, 23, .06), 0 18px 45px rgba(2, 6, 23, .14), 0 6px 18px rgba(59, 130, 246, .18);
    --space-section: 2rem;
    --space-card: 1rem;
    --space-gap: 0.75rem;
    --transition: 0.52s cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 600;
    --body-line-height: 1.65;
    --backdrop-glow: rgba(59, 130, 246, .14);
    --card-border: rgba(148, 163, 184, .28);
    --card-border-strong: rgba(59, 130, 246, .30);
    --focus-ring: rgba(59, 130, 246, .45);
}

/* 基础覆盖 */
body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background:
        radial-gradient(1200px 700px at 10% -10%, rgba(59, 130, 246, .20), transparent 55%),
        radial-gradient(900px 600px at 95% 0%, rgba(96, 165, 250, .16), transparent 50%),
        linear-gradient(180deg, #0b1224 0%, #0f172a 40%, #0b1224 100%);
    accent-color: var(--color-primary);
}
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:
        0 1px 0 rgba(248, 250, 252, .10),
        0 0 0 1px rgba(59, 130, 246, .10),
        0 18px 40px rgba(2, 6, 23, .28),
        0 2px 10px rgba(59, 130, 246, .12);
    padding: var(--space-card);
    transition: var(--transition);
    background:
        linear-gradient(180deg, rgba(255,255,255,.92) 0%, rgba(248,250,252,.84) 100%);
    color: var(--color-text);
    border: 1px solid transparent;
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: 0.48s cubic-bezier(0.22, 1, 0.36, 1);
    box-shadow:
        0 1px 0 rgba(255,255,255,.35),
        0 14px 30px rgba(2, 6, 23, .18),
        0 0 0 1px rgba(59, 130, 246, .25);
}
a:not([class]) { color: var(--color-primary); transition: var(--transition); }
a:not([class]):focus { outline: 2px solid var(--focus-ring); outline-offset: 2px; }

/* ========== 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) * 0.8); }

/* features: horizontal */
/* 水平滚动 */
                .feature-list { display: flex; gap: var(--space-gap); overflow-x: auto; scroll-snap-type: x mandatory; }
                .feature-list > * { flex: 0 0 300px; scroll-snap-align: start; }

/* 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: 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: narrow-centered */
/* 窄版居中 */
            .page-main { max-width: 860px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover, [class*="card"]:hover {
    transform: translateY(-4px);
    box-shadow:
        0 1px 0 rgba(255,255,255,.35),
        0 0 0 1px rgba(59, 130, 246, .22),
        0 30px 70px rgba(2, 6, 23, .32),
        0 10px 26px rgba(59, 130, 246, .22);
}
.card { border: 1px solid rgba(var(--rgb-primary), .14); }

header, .header, .navbar {
    background: linear-gradient(180deg, rgba(15, 23, 42, .72) 0%, rgba(15, 23, 42, .25) 100%);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(148, 163, 184, .16);
    box-shadow:
        0 8px 26px rgba(2, 6, 23, .35),
        0 0 0 1px rgba(59, 130, 246, .10);
}

/* 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; }
}