:root {
    --color-primary: #2a3d66;
    --color-primary-dark: #1e2a4f;
    --color-accent: #7a9edc;
    --color-surface: #e6ebf8;
    --color-text: #202940;
    --rgb-primary: 42,61,102;
    --rgb-accent: 122,158,220;
    --radius-sm: 1px;
    --radius-md: 3px;
    --radius-lg: 4px;
    --radius-xl: 4px;
    --shadow-sm: 4px 4px 0 rgba(42,61,102,0.3), -4px -4px 0 rgba(122,158,220,0.2);
    --shadow-md: 6px 6px 0 rgba(42,61,102,0.45), -6px -6px 0 rgba(122,158,220,0.3);
    --shadow-lg: 8px 8px 0 rgba(42,61,102,0.6), -8px -8px 0 rgba(122,158,220,0.4);
    --space-section: 4rem;
    --space-card: 1.5rem;
    --space-gap: 1.25rem;
    --transition: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --heading-weight: 700;
    --body-line-height: 1.65;
}

/* 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: var(--shadow-md);
    padding: var(--space-card);
    transition: box-shadow var(--transition), transform var(--transition);
    border: 3px solid var(--color-primary-dark);
    background: linear-gradient(135deg, var(--color-surface) 0%, #c8d0f2 100%);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: background-color var(--transition), color var(--transition), border-color var(--transition);
    border: 2.5px solid var(--color-primary);
    background-color: var(--color-primary);
    color: var(--color-surface);
    caret-color: var(--color-accent);
    accent-color: var(--color-accent);
}
a:not([class]) {
    color: var(--color-primary);
    text-shadow: 1px 1px 0 rgba(122,158,220,0.7);
    transition: color var(--transition), text-shadow var(--transition);
}

/* ========== 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);
    border-radius: var(--radius-sm);
    box-shadow:
        4px 4px 0 rgba(42,61,102,0.5),
        -4px -4px 0 rgba(122,158,220,0.3);
    border: 2.5px solid var(--color-primary);
    background: radial-gradient(circle at top left, #e2e8ff 0%, var(--color-surface) 90%);
}

/* features: grid-3 */
.feature-list {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-gap);
}

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

/* testimonials: masonry */
.testimonial-list {
    column-count: 2;
    column-gap: var(--space-gap);
}
.testimonial-list > * {
    break-inside: avoid;
    margin-bottom: var(--space-gap);
    border-radius: var(--radius-sm);
    box-shadow:
        4px 4px 0 rgba(42,61,102,0.45),
        -4px -4px 0 rgba(122,158,220,0.25);
    border: 2px solid var(--color-primary-dark);
    background: linear-gradient(90deg, #d0dafd 0%, var(--color-surface) 100%);
}

/* partners: centered */
.partner-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2rem;
}

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

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

/* cta: split */
.cta-inner {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 2rem;
}

/* 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(-4px);
    box-shadow:
        8px 8px 0 rgba(29,43,79,0.8),
        -8px -8px 0 rgba(102,133,210,0.5);
    border-color: var(--color-accent);
    transition: box-shadow 0.15s cubic-bezier(0.4, 0, 0.2, 1), transform 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}
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;
    }
}