:root {
    --color-primary: #0ea5e9;
    --color-primary-dark: #0369a1;
    --color-accent: #22c55e;
    --color-surface: #f6fbff;
    --color-text: #0b1220;
    --rgb-primary: 14,165,233;
    --rgb-accent: 34,197,94;
    --radius-sm: 4px;
    --radius-md: 6px;
    --radius-lg: 10px;
    --radius-xl: 14px;
    --shadow-sm: 0 1px 0 rgba(3,105,161,.10), 0 4px 10px rgba(2,132,199,.10);
    --shadow-md: 0 6px 14px rgba(2,132,199,.14), 0 2px 6px rgba(2,132,199,.10);
    --shadow-lg: 0 16px 34px rgba(2,132,199,.18), 0 6px 16px rgba(3,105,161,.12);
    --space-section: 4rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;
    --transition: 280ms cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 600;
    --body-line-height: 1.6;
}

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 1px 0 rgba(11,18,32,.06),
        0 10px 24px rgba(3,105,161,.10),
        0 2px 10px rgba(14,165,233,.08);
    padding: var(--space-card);
    transition: var(--transition);
}
.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); }

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

/* news: featured-left */
/* 左大右小 (1大+2小) */
                .news-grid { display: grid; grid-template-columns: 2fr 1fr; grid-template-rows: auto auto; gap: var(--space-gap); }
                .news-grid > *:first-child { grid-row: span 2; }

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

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

/* testimonials: grid-3 */
.testimonial-list { display: grid; grid-template-columns: repeat(3, 1fr); gap: 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: single-column */
.faq-list { max-width: 800px; margin: 0 auto; }

/* stats: grid-3 */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); text-align: center; }

/* cta: full-bg */
.cta-section {
    background:
        radial-gradient(1200px 420px at 20% 10%, rgba(34,197,94,.35) 0%, rgba(34,197,94,0) 52%),
        radial-gradient(1000px 360px at 85% 20%, rgba(14,165,233,.40) 0%, rgba(14,165,233,0) 55%),
        linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: #f8fbff;
    padding: 4rem 2rem;
}

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

/* 条件性装饰 */
.card { border: 1px solid rgba(var(--rgb-primary), .12); }
header, .header, .navbar {
    box-shadow:
        0 1px 0 rgba(255,255,255,.55) inset,
        0 10px 24px rgba(2,132,199,.10),
        0 2px 10px rgba(3,105,161,.08);
}

/* 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; }
}