:root {
    --color-primary: #2c3e50;
    --color-primary-dark: #0b1220;
    --color-accent: #2dd4bf;
    --color-surface: #f7fafc;
    --color-text: #0f172a;
    --rgb-primary: 44,62,80;
    --rgb-accent: 45,212,191;
    --rgb-surface: 247,250,252;

    --radius-sm: 5px;
    --radius-md: 10px;
    --radius-lg: 18px;
    --radius-xl: 22px;

    --shadow-sm:
        0 2px 10px rgba(9, 14, 26, 0.06),
        0 10px 22px -14px rgba(9, 14, 26, 0.20);
    --shadow-md:
        0 4px 12px rgba(9, 14, 26, 0.08),
        0 18px 36px -18px rgba(9, 14, 26, 0.24),
        0 1px 0 rgba(255,255,255,0.55) inset;
    --shadow-lg:
        0 10px 28px rgba(9, 14, 26, 0.10),
        0 30px 60px -28px rgba(9, 14, 26, 0.28),
        0 1px 0 rgba(255,255,255,0.52) inset;

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

    --transition: 420ms ease-in-out;
    --transition-fast: 300ms cubic-bezier(0.2, 0.8, 0.2, 1);

    --heading-weight: 650;
    --body-line-height: 1.65;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); }
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 4px 14px rgba(9, 14, 26, 0.08),
        0 18px 40px -22px rgba(9, 14, 26, 0.28),
        0 1px 0 rgba(255,255,255,0.60) inset;
    padding: var(--space-card);
    transition: var(--transition);
    background: linear-gradient(180deg, rgba(var(--rgb-surface),0.98), rgba(var(--rgb-surface),0.92));
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: var(--transition);
}
a:not([class]) { color: var(--color-primary); transition: var(--transition); }
a:not([class]):hover { color: var(--color-accent); }

.rail-accent {
    outline-color: var(--color-accent);
    caret-color: var(--color-accent);
    accent-color: var(--color-accent);
}

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

/* news: featured-top */
/* 首篇横跨全宽 */
                .news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); }
                .news-grid > *:first-child { grid-column: span 3; }

/* features: grid-2 */
.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: calc(var(--space-gap) * 1.5); }

/* hero: centered */
.hero-content { text-align: center; max-width: 800px; margin: 0 auto; }

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

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

/* faq: with-sidebar */
/* FAQ 左 + 联系信息右 */
                .faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 2rem; }

/* 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; }

/* cta: card-style */
.cta-inner {
    background:
        radial-gradient(1200px 420px at 20% 0%, rgba(45, 212, 191, 0.16), rgba(45, 212, 191, 0) 55%),
        linear-gradient(180deg, rgba(255,255,255,0.96), rgba(247,250,252,0.92));
    border-radius: var(--radius-xl);
    padding: 3rem;
    text-align: center;
    box-shadow:
        0 10px 30px rgba(9, 14, 26, 0.10),
        0 30px 70px -38px rgba(9, 14, 26, 0.28);
}

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

/* 条件性装饰 */
.hero, [class*="hero"], section:first-of-type {
    background:
        radial-gradient(900px 360px at 10% 15%, rgba(45, 212, 191, 0.22), rgba(45, 212, 191, 0) 55%),
        radial-gradient(700px 300px at 85% 5%, rgba(99, 102, 241, 0.18), rgba(99, 102, 241, 0) 60%),
        linear-gradient(135deg, #233246, #0b1220);
    box-shadow:
        0 14px 40px -22px rgba(9, 14, 26, 0.40),
        0 1px 0 rgba(255,255,255,0.10) inset;
}
.card { border-left: 3px solid var(--color-accent); }

/* 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; }
}