:root {
    --color-primary: #0f172a;
    --color-primary-dark: #0b1222;
    --color-accent: #3b82f6;
    --color-surface: #ffffff;
    --color-text: #cbd5e1;
    --rgb-primary: 15,23,42;
    --rgb-accent: 59,130,246;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 14px;
    --radius-xl: 18px;

    --shadow-sm:
        0 1px 0 rgba(2,6,23,.25),
        0 6px 16px rgba(2,6,23,.10);
    --shadow-md:
        0 8px 24px rgba(2,6,23,.22),
        0 2px 0 rgba(255,255,255,.25) inset;
    --shadow-lg:
        0 18px 50px rgba(2,6,23,.35),
        0 2px 0 rgba(255,255,255,.30) inset,
        0 0 0 1px rgba(59,130,246,.20);

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

    --transition: 0.52s cubic-bezier(0.2, 0.9, 0.2, 1);
    --heading-weight: 800;
    --body-line-height: 1.7;

    --color-ink: #0b1222;
    --color-muted: rgba(203,213,225,.78);
    --color-border: rgba(148,163,184,.35);

    --shadow-frost:
        0 0 0 1px rgba(148,163,184,.22) inset,
        0 10px 30px rgba(2,6,23,.22);
}

/* 基础覆盖 */
body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background:
        radial-gradient(900px 500px at 15% 10%, rgba(59,130,246,.22) 0%, rgba(59,130,246,0) 55%),
        radial-gradient(700px 420px at 85% 5%, rgba(99,102,241,.18) 0%, rgba(99,102,241,0) 60%),
        linear-gradient(180deg, #0b1222 0%, #0f172a 55%, #0a1020 100%);
    accent-color: var(--color-accent);
}
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(255,255,255,.35) inset,
        0 -1px 0 rgba(2,6,23,.22) inset,
        0 14px 34px rgba(2,6,23,.32);
    padding: var(--space-card);
    transition:
        transform calc(var(--transition) * 1) ease,
        box-shadow calc(var(--transition) * 1) ease,
        border-color calc(var(--transition) * 1) ease,
        background calc(var(--transition) * 1) ease,
        filter calc(var(--transition) * 1) ease;
    background:
        linear-gradient(180deg, rgba(255,255,255,.98) 0%, rgba(255,255,255,.90) 100%);
    outline: 1px solid rgba(148,163,184,.18);
    outline-offset: -1px;
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition:
        transform calc(var(--transition) * 0.9) ease,
        background calc(var(--transition) * 0.9) ease,
        box-shadow calc(var(--transition) * 0.9) ease,
        color calc(var(--transition) * 0.9) ease,
        border-color calc(var(--transition) * 0.9) ease;
    border-color: rgba(59,130,246,.35);
    border-style: solid;
    border-width: 0;
}
a:not([class]) {
    color: #60a5fa;
    transition: color calc(var(--transition) * 0.9) ease, text-shadow calc(var(--transition) * 0.9) ease;
    text-shadow: 0 0 0 rgba(0,0,0,0);
}
a:not([class]):focus { outline: 2px solid rgba(59,130,246,.55); outline-offset: 3px; }

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

/* news: grid-3 */
/* 三列等宽网格 */
                .news-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 0.875rem; }

/* features: grid-2 */
.feature-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 0.75rem; }

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

/* testimonials: carousel */
/* 单条轮播 */
                .testimonial-list { display: flex; overflow: hidden; }
                .testimonial-list > * { flex: 0 0 100%; }

/* partners: centered */
.partner-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 1.25rem; }

/* faq: with-sidebar */
/* FAQ 左 + 联系信息右 */
                .faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 1.25rem; }

/* stats: grid-3 */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0.875rem; text-align: center; }

/* cta: full-bg */
.cta-section {
    color: #f8fafc;
    padding: 4rem 2rem;
    background:
        radial-gradient(1200px 500px at 10% 30%, rgba(59,130,246,.55) 0%, rgba(59,130,246,0) 60%),
        radial-gradient(900px 450px at 80% 10%, rgba(99,102,241,.35) 0%, rgba(99,102,241,0) 55%),
        linear-gradient(180deg, rgba(15,23,42,1) 0%, rgba(17,24,39,1) 55%, rgba(11,18,34,1) 100%);
    box-shadow:
        0 20px 60px rgba(2,6,23,.45),
        0 0 0 1px rgba(59,130,246,.25) inset;
}

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

/* 条件性装饰 */
.card:hover, [class*="card"]:hover {
    transform: translateY(-5px);
    box-shadow:
        0 22px 70px rgba(2,6,23,.45),
        0 2px 0 rgba(255,255,255,.42) inset,
        0 0 0 1px rgba(59,130,246,.35);
    filter: saturate(1.05) contrast(1.02);
    outline: 1px solid rgba(59,130,246,.40);
    outline-offset: -1px;
}
header, .header, .navbar {
    background: transparent;
    backdrop-filter: blur(0px);
}

/* Responsive */
@media (max-width: 1024px) {
    .news-grid { grid-template-columns: repeat(3, 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; }
}