:root {
    --color-primary: #1a4f63;
    --color-primary-dark: #103d4f;
    --color-accent: #33a1c9;
    --color-surface: #e9f4f8;
    --color-text: #0b2e3d;
    --rgb-primary: 26,79,99;
    --rgb-accent: 51,161,201;
    --radius-sm: 10px;
    --radius-md: 14px;
    --radius-lg: 18px;
    --radius-xl: 28px;
    --shadow-sm: 0 2px 6px rgba(51,161,201,0.15);
    --shadow-md: 0 4px 10px rgba(51,161,201,0.25), 0 0 12px rgba(51,161,201,0.18);
    --shadow-lg: 0 8px 20px rgba(16,61,79,0.3), 0 0 24px rgba(51,161,201,0.25);
    --space-section: 3.5rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --heading-weight: 800;
    --body-line-height: 1.6;
}

/* 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 0 8px rgba(var(--rgb-accent), 0.35),
        0 4px 16px rgba(16,61,79,0.3),
        inset 0 0 6px rgba(51,161,201,0.2);
    padding: var(--space-card);
    transition: box-shadow var(--transition), background-color var(--transition);
    background: var(--color-surface);
    border: 1px solid rgba(var(--rgb-primary), 0.12);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: background-color var(--transition), color var(--transition);
    caret-color: var(--color-accent);
    accent-color: var(--color-accent);
}
a:not([class]) {
    color: var(--color-primary);
    transition: color 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: grid-3 */
.feature-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-gap);
}

/* 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: 2rem;
    overflow: hidden;
    animation: partnerScroll 20s linear infinite;
}
@keyframes partnerScroll {
    0% { transform: translateX(0); }
    100% { transform: translateX(-50%); }
}

/* faq: two-column */
.faq-list {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-gap);
}

/* stats: grid-4 */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-gap);
    text-align: center;
}

/* cta: centered */
.cta-inner {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

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

/* 条件性装饰 */
.hero, [class*="hero"], section:first-of-type {
    background: linear-gradient(135deg, #1a4f63, #103d4f);
}
.card {
    border: 1px solid rgba(var(--rgb-primary), 0.12);
    box-shadow:
        0 0 24px rgba(var(--rgb-accent), 0.4),
        0 4px 12px rgba(16,61,79,0.35),
        inset 0 0 8px rgba(51,161,201,0.25);
    border-radius: var(--radius-lg);
    transition: box-shadow 0.35s cubic-bezier(0.4,0,0.2,1);
}
.card:hover, .card:focus-within {
    box-shadow:
        0 0 32px rgba(var(--rgb-accent), 0.6),
        0 8px 20px rgba(16,61,79,0.4),
        inset 0 0 12px rgba(51,161,201,0.35);
    outline: 2px solid rgba(var(--rgb-accent), 0.6);
    outline-offset: 2px;
}
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: 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; }
}