:root {
    --color-primary: #0ea5e9;
    --color-primary-dark: #0369a1;
    --color-accent: #22c55e;
    --color-surface: #f0fdf4;
    --color-text: #052e2b;

    --rgb-primary: 14,165,233;
    --rgb-accent: 34,197,94;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 20px;

    --shadow-sm: 0 4px 10px rgba(0,0,0,.06), 0 1px 0 rgba(255,255,255,.35) inset;
    --shadow-md: 0 8px 22px rgba(2, 132, 199, .14), 0 3px 10px rgba(0,0,0,.06);
    --shadow-lg: 0 14px 40px -12px rgba(2, 132, 199, .26), 0 22px 60px -28px rgba(0,0,0,.24);

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

    --transition: 0.38s cubic-bezier(.2,.8,.2,1);
    --heading-weight: 650;
    --body-line-height: 1.75;
}

/* 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 10px rgba(2, 132, 199, .10),
        0 20px 50px -18px rgba(0,0,0,.28),
        0 1px 0 rgba(255,255,255,.55) inset;
    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); }

.card { border: 1px solid rgba(var(--rgb-primary), .18); }

:focus-visible, :focus { outline: 2px solid rgba(var(--rgb-primary), .35); outline-offset: 3px; }
::selection { background: rgba(var(--rgb-primary), .22); color: inherit; }
body { caret-color: var(--color-primary); }

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

/* news: masonry-2 */
/* 两列瀑布流 */
                .news-grid { column-count: 2; column-gap: var(--space-gap); }
                .news-grid .card {
                    break-inside: avoid;
                    margin-bottom: var(--space-gap);
                    background: rgba(255,255,255,.72);
                    backdrop-filter: blur(8px);
                }

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

/* hero: split */
/* 左文右图 */
                .hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: center; }

/* 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: 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 22px rgba(2,132,199,.20); }

/* cta: card-style */
.cta-inner {
    background:
        radial-gradient(1200px 500px at 20% 0%, rgba(34,197,94,.18), transparent 55%),
        radial-gradient(900px 420px at 90% 20%, rgba(14,165,233,.20), transparent 52%),
        linear-gradient(180deg, rgba(255,255,255,.60), rgba(255,255,255,.35)),
        var(--color-surface);
    border-radius: var(--radius-xl);
    padding: 3rem;
    text-align: center;
    box-shadow:
        0 18px 55px -28px rgba(0,0,0,.30),
        0 10px 24px rgba(2,132,199,.16),
        0 1px 0 rgba(255,255,255,.7) inset;
    transition: var(--transition);
}

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

/* 条件性装饰 */
a:not([class]):hover { color: var(--color-accent); text-shadow: 0 10px 24px rgba(34,197,94,.20); }
.hero, [class*="hero"], section:first-of-type {
    background:
        radial-gradient(900px 520px at 15% 15%, rgba(34,197,94,.22), transparent 55%),
        radial-gradient(780px 520px at 90% 20%, rgba(14,165,233,.30), transparent 60%),
        linear-gradient(135deg, #0ea5e9, #0369a1);
    border-radius: var(--radius-xl);
    box-shadow:
        0 10px 34px -18px rgba(0,0,0,.35),
        0 18px 70px -35px rgba(2,132,199,.35);
}
header, .header, .navbar { background: transparent; }

/* 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; }
}