:root {
    --color-primary: #6d28d9;
    --color-primary-dark: #4c1d95;
    --color-accent: #d97706;
    --color-surface: #faf5ff;
    --color-text: #1e1b4b;
    --rgb-primary: 109,40,217;
    --rgb-accent: 217,119,6;
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --shadow-sm: 0 2px 10px rgba(15,23,42,.04), 0 8px 24px -8px rgba(15,23,42,.08);
    --shadow-md: 0 6px 18px -6px rgba(15,23,42,.08), 0 24px 48px -12px rgba(15,23,42,.18);
    --shadow-lg: 0 10px 30px -8px rgba(15,23,42,.12), 0 40px 80px -16px rgba(15,23,42,.22);
    --space-section: 3.6rem;
    --space-card: 1.5rem;
    --space-gap: 1.2rem;
    --transition: 0.6s cubic-bezier(0.22, 1, 0.36, 1);
    --heading-weight: 600;
    --body-line-height: 1.75;
}

/* 基础覆盖 */
body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background-color: var(--color-surface);
    background-image: radial-gradient(circle at 20% 15%, rgba(255,255,255,.5), transparent 50%), radial-gradient(circle at 85% 80%, rgba(109,40,217,.06), transparent 45%);
}

h1, h2, h3, h4 {
    font-weight: var(--heading-weight);
    text-shadow: 0 2px 16px rgba(15,23,42,.08);
}

section, .section {
    padding-top: var(--space-section);
    padding-bottom: var(--space-section);
    background-color: var(--color-surface);
}

section:nth-of-type(4n+1), .section:nth-of-type(4n+1) { background-color: #ffffff; }
section:nth-of-type(4n+2), .section:nth-of-type(4n+2) { background-color: var(--color-surface); }
section:nth-of-type(4n+3), .section:nth-of-type(4n+3) { background-color: var(--color-primary-dark); color: #f8fafc; --color-primary: #a78bfa; --color-accent: #fbbf24; }
section:nth-of-type(4n+4), .section:nth-of-type(4n+4) { background-color: #ffffff; }

.card, [class*="card"] {
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md), inset 0 0 0 1px rgba(255,255,255,.4);
    padding: var(--space-card);
    transition: var(--transition);
    background-color: rgba(255,255,255,.9);
    backdrop-filter: blur(8px);
}

.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: var(--transition);
    box-shadow: 0 12px 28px -12px rgba(var(--rgb-primary), .7);
}

a:not([class]) {
    color: var(--color-primary);
    transition: var(--transition);
}

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

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

/* features: horizontal */
/* 水平滚动 */
.feature-list {
    display: flex;
    gap: var(--space-gap);
    overflow-x: auto;
    scroll-snap-type: x mandatory;
}

.feature-list > * {
    flex: 0 0 300px;
    scroll-snap-align: start;
}

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

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

.testimonial-list > * {
    flex: 0 0 100%;
}

/* partners: scroll */
/* 自动滚动 */
.partner-grid {
    display: flex;
    gap: 2.4rem;
    overflow: hidden;
    animation: partnerScroll 28s linear infinite;
}

@keyframes partnerScroll {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* faq: single-column */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

/* stats: inline */
/* 水平排列 */
.stats-grid {
    display: flex;
    justify-content: center;
    gap: 3.6rem;
}

/* cta: split */
.cta-inner {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 2.4rem;
}

/* Page Layout: full-width */
/* 无侧边栏, 全宽 */
.page-main {
    max-width: 1200px;
    margin: 0 auto;
}

/* 条件性装饰 */
a:not([class]):hover {
    color: var(--color-accent);
}

.card {
    border-left: 3px solid var(--color-primary);
}

header, .header, .navbar {
    box-shadow: 0 6px 24px -10px rgba(15,23,42,.12), inset 0 -1px 0 rgba(15,23,42,.04);
    background-color: rgba(255,255,255,.72);
    backdrop-filter: blur(16px);
}

/* 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: 2.4rem;
        --space-card: 1.2rem;
        --space-gap: 0.9rem;
    }
    .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; }
}