:root {
    --color-primary: #0ea5e9;
    --color-primary-dark: #075985;
    --color-accent: #22c55e;
    --color-surface: #f0fdf4;
    --color-text: #0b1b14;
    --rgb-primary: 14,165,233;
    --rgb-accent: 34,197,94;

    --radius-sm: 4px;
    --radius-md: 5px;
    --radius-lg: 6px;
    --radius-xl: 10px;

    --shadow-sm: 0 1px 0 rgba(2, 6, 23, .06);
    --shadow-md:
        0 1px 0 rgba(2, 6, 23, .05),
        0 6px 14px rgba(2, 6, 23, .08);
    --shadow-lg:
        0 1px 0 rgba(2, 6, 23, .06),
        0 10px 22px rgba(2, 6, 23, .12),
        0 2px 6px rgba(14, 165, 233, .12);

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

    --transition: 240ms cubic-bezier(.2,.9,.2,1);
    --heading-weight: 600;
    --body-line-height: 1.7;
}

/* 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 1px 0 rgba(2, 6, 23, .05),
        0 4px 10px rgba(2, 6, 23, .07);
    padding: var(--space-card);
    transition:
        transform var(--transition),
        box-shadow var(--transition),
        border-color var(--transition),
        background-color var(--transition),
        color var(--transition);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition:
        background-color var(--transition),
        border-color var(--transition),
        color var(--transition),
        box-shadow var(--transition),
        transform var(--transition);
}
a:not([class]) {
    color: var(--color-primary);
    transition: var(--transition);
    text-shadow: 0 1px 0 rgba(255,255,255,.5);
}

/* ========== 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-6 */
.partner-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: var(--space-gap); align-items: center; }

/* 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: full-bg */
.cta-section {
    background:
        radial-gradient(1200px 260px at 20% 10%, rgba(34,197,94,.25) 0%, rgba(34,197,94,0) 55%),
        radial-gradient(900px 240px at 90% 20%, rgba(14,165,233,.28) 0%, rgba(14,165,233,0) 60%),
        linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: #f7feff;
    padding: 4rem 2rem;
    box-shadow:
        0 1px 0 rgba(2, 6, 23, .12),
        0 18px 44px rgba(2, 6, 23, .22);
}

/* 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(2, 6, 23, .07),
        0 10px 26px rgba(2, 6, 23, .14),
        0 2px 10px rgba(14, 165, 233, .15);
}
a:not([class]):hover {
    color: var(--color-accent);
    text-shadow: 0 1px 0 rgba(255,255,255,.45);
}

/* 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-sm: 3px;
        --radius-md: 4px;
        --radius-lg: 5px;

        --transition: 200ms cubic-bezier(.2,.85,.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; }
}