:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-accent: #7c3aed;
    --color-surface: #f3f4f6;
    --color-text: #111827;
    --rgb-primary: 37,99,235;
    --rgb-accent: 124,58,237;

    --radius-sm: 6px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 22px;

    --shadow-sm: 0 2px 6px rgba(17,24,39,0.07), 0 1px 0 rgba(255,255,255,0.55) inset;
    --shadow-md: 0 6px 16px rgba(17,24,39,0.10), 0 2px 0 rgba(255,255,255,0.7) inset;
    --shadow-lg: 0 10px 26px rgba(17,24,39,0.14), 0 26px 60px -18px rgba(17,24,39,0.28);

    --space-section: 3rem;
    --space-card: 1.25rem;
    --space-gap: 1rem;

    --transition: 0.35s cubic-bezier(0.2, 0.8, 0.2, 1);
    --heading-weight: 800;
    --body-line-height: 1.75;
}

body { color: var(--color-text); line-height: var(--body-line-height); background: var(--color-surface); }

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 10px rgba(17,24,39,0.06),
        0 20px 46px -14px rgba(17,24,39,0.18),
        0 1px 0 rgba(255,255,255,0.75) inset;
    padding: var(--space-card);
    transition: var(--transition);
    background: #ffffff;
}

.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: var(--transition);
    box-shadow:
        0 4px 12px rgba(37,99,235,0.12),
        0 1px 0 rgba(255,255,255,0.85) inset;
}

a:not([class]) {
    color: var(--color-primary);
    transition: var(--transition);
    text-decoration-thickness: 1px;
    text-underline-offset: 3px;
}

a:not([class]):focus { outline: 2px solid rgba(var(--rgb-accent), 0.35); outline-offset: 2px; }

:where(.card, [class*="card"]) { border: 1px solid rgba(var(--rgb-primary), 0.10); }
.card { border: 1px solid rgba(var(--rgb-primary), .10); }

section.hero,
.hero,
[class*="hero"] {
    border-radius: var(--radius-xl);
}

.card:hover, [class*="card"]:hover {
    transform: translateY(-5px);
    box-shadow:
        0 10px 24px rgba(17,24,39,0.10),
        0 40px 90px -34px rgba(17,24,39,0.26),
        0 1px 0 rgba(255,255,255,0.85) inset;
}

a:not([class]):hover { color: var(--color-accent); }

.hero, [class*="hero"], section:first-of-type {
    background:
        radial-gradient(900px 220px at 15% 10%, rgba(124,58,237,0.22), transparent 55%),
        radial-gradient(700px 240px at 85% 10%, rgba(37,99,235,0.18), transparent 58%),
        linear-gradient(135deg, #1d4ed8 0%, #2563eb 38%, #3730a3 100%);
}

header, .header, .navbar {
    box-shadow:
        0 2px 10px rgba(17,24,39,0.06),
        0 10px 26px -16px rgba(17,24,39,0.20);
    border-bottom: 1px solid rgba(17,24,39,0.06);
}

/* ========== 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: centered */
/* 居中大卡片 */
                .feature-list { display: flex; flex-direction: column; align-items: center; gap: calc(var(--space-gap) * 2); max-width: 720px; margin: 0 auto; }

/* hero: minimal */
.hero { padding: 2rem 0; } .hero-content { max-width: 560px; }

/* testimonials: stacked */
/* 垂直堆叠 */
                .testimonial-list { display: flex; flex-direction: column; gap: var(--space-gap); max-width: 720px; margin: 0 auto; }

/* 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: 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 1px 0 rgba(255,255,255,0.9), 0 12px 30px rgba(29,78,216,0.10); }

/* cta: full-bg */
.cta-section { background: linear-gradient(135deg, #2563eb 0%, #4f46e5 55%, #7c3aed 100%); color: #ffffff; padding: 4rem 2rem; }
.cta-section :where(a:not([class])) { color: #ffffff; }
.cta-section :where(a:not([class]):hover) { color: rgba(255,255,255,0.92); }

/* Page Layout: wide */
/* 超宽 */
            .page-main { max-width: 1400px; margin: 0 auto; }

/* 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; }
}