:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #1d4ed8;
    --color-accent: #60a5fa;
    --color-surface: #0b1220;
    --color-text: #e5eaf3;

    --rgb-primary: 59,130,246;
    --rgb-accent: 96,165,250;

    --radius-sm: 3px;
    --radius-md: 4px;
    --radius-lg: 6px;
    --radius-xl: 8px;

    --shadow-sm: 0 1px 0 rgba(148,163,184,.12);
    --shadow-md: 0 10px 22px rgba(2,6,23,.38), 0 2px 6px rgba(2,6,23,.22), inset 0 1px 0 rgba(255,255,255,.04);
    --shadow-lg: 0 16px 34px rgba(2,6,23,.48), 0 4px 10px rgba(2,6,23,.28), inset 0 1px 0 rgba(255,255,255,.05);

    --space-section: 4rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;

    --transition: 160ms cubic-bezier(.2,.8,.2,1);
    --heading-weight: 700;
    --body-line-height: 1.6;
}

/* 基础覆盖 */
body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background:
        radial-gradient(1200px 420px at 10% -10%, rgba(59,130,246,.18), rgba(59,130,246,0) 60%),
        radial-gradient(900px 360px at 90% 0%, rgba(96,165,250,.14), rgba(96,165,250,0) 55%),
        linear-gradient(180deg, #0f172a 0%, #0b1220 55%, #0a1020 100%);
    caret-color: var(--color-accent);
}
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(255,255,255,.05),
        0 14px 30px rgba(2,6,23,.35),
        0 2px 8px rgba(2,6,23,.22);
    padding: var(--space-card);
    transition:
        box-shadow var(--transition),
        transform var(--transition),
        border-color var(--transition),
        background-color var(--transition),
        filter var(--transition);
    background:
        linear-gradient(180deg, rgba(30,41,59,.92) 0%, rgba(15,23,42,.92) 100%);
    border: 1px solid rgba(148,163,184,.14);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition:
        background-color var(--transition),
        box-shadow var(--transition),
        transform var(--transition),
        color var(--transition),
        border-color var(--transition);
    border: 1px solid rgba(148,163,184,.18);
    box-shadow: 0 6px 18px rgba(2,6,23,.25), inset 0 1px 0 rgba(255,255,255,.05);
}
a:not([class]) {
    color: var(--color-primary);
    transition: var(--transition);
    text-shadow: 0 1px 0 rgba(0,0,0,.25);
}
a:not([class]):focus {
    outline: 2px solid rgba(96,165,250,.45);
    outline-offset: 3px;
}

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

/* hero: minimal */
.hero { padding: 2rem 0; } .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: grid-6 */
.partner-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: var(--space-gap); align-items: center; }

/* faq: two-column */
.faq-list { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-gap); }

/* 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 28px rgba(2,6,23,.55); }

/* cta: centered */
.cta-inner { text-align: center; max-width: 700px; margin: 0 auto; }

/* 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(-3px);
    box-shadow:
        0 1px 0 rgba(255,255,255,.06),
        0 20px 44px rgba(2,6,23,.55),
        0 6px 16px rgba(2,6,23,.30),
        inset 0 1px 0 rgba(255,255,255,.07);
    filter: saturate(1.02) contrast(1.02);
    border-color: rgba(96,165,250,.28);
}
a:not([class]):hover { color: var(--color-accent); text-shadow: 0 8px 22px rgba(59,130,246,.25); }
.hero, [class*="hero"], section:first-of-type {
    background:
        radial-gradient(900px 420px at 20% 0%, rgba(59,130,246,.20), rgba(59,130,246,0) 60%),
        radial-gradient(840px 360px at 88% 18%, rgba(96,165,250,.16), rgba(96,165,250,0) 55%),
        linear-gradient(135deg, #1e293b 0%, #334155 60%, #0b1220 100%);
    border-bottom: 1px solid rgba(148,163,184,.10);
}
.card { border-left: 3px solid var(--color-primary); border-left-color: var(--color-primary); }

/* 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;
        --radius-lg: 6px;
        --transition: 140ms cubic-bezier(.25,.9,.2,1);
    }
    .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; }
}