:root {
    --color-primary: #0e7490;
    --color-primary-dark: #155e75;
    --color-accent: #22d3ee;
    --color-surface: #f8fafc;
    --color-text: #1e293b;
    --rgb-primary: 14, 116, 144;
    --rgb-accent: 34, 211, 238;
    --radius-sm: 0px;
    --radius-md: 2px;
    --radius-lg: 4px;
    --radius-xl: 4px;
    --shadow-sm: 3px 3px 0 0 rgba(37, 46, 58, 0.12), 0 0 0 1px #252e3a;
    --shadow-md: 4px 4px 0 0 rgba(37, 46, 58, 0.2), 0 0 0 2px #252e3a;
    --shadow-lg: 6px 6px 0 0 rgba(37, 46, 58, 0.28), 0 0 0 2px #252e3a;
    --space-section: 3.5rem;
    --space-card: 1.375rem;
    --space-gap: 1.125rem;
    --transition: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --heading-weight: 600;
    --body-line-height: 1.75;
}

/* 基础覆盖 */
body {
    background-color: var(--color-surface);
    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: var(--transition);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-sm);
    box-shadow: 3px 3px 0 0 rgba(37, 46, 58, 0.18);
    transition: var(--transition);
}
a:not([class]) {
    color: var(--color-primary);
    transition: var(--transition);
}

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

/* news: featured-left */
/* 左大右小 (1大+2小) */
.news-grid {
    display: grid;
    grid-template-columns: 2fr 1fr;
    grid-template-rows: auto auto;
    gap: var(--space-gap);
}
.news-grid > *:first-child { grid-row: span 2; }

/* features: centered */
/* 居中大卡片 */
.feature-list {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: calc(var(--space-gap) * 2);
    max-width: 720px;
    margin: 0 auto;
}

/* hero: left-aligned */
.hero-content { text-align: left; max-width: 600px; }

/* testimonials: stacked */
/* 垂直堆叠 */
.testimonial-list {
    display: flex;
    flex-direction: column;
    gap: var(--space-gap);
    max-width: 720px;
    margin: 0 auto;
}

/* partners: centered */
.partner-grid {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 2.25rem;
}

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

/* stats: inline */
/* 水平排列 */
.stats-grid {
    display: flex;
    justify-content: center;
    gap: 3.5rem;
}

/* cta: split */
.cta-inner {
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 2.25rem;
}

/* 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: var(--shadow-lg);
}
header, .header, .navbar {
    box-shadow: 4px 4px 0 0 rgba(37, 46, 58, 0.2), 0 0 0 1px #252e3a;
}

/* 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: 2.25rem;
        --space-card: 1.125rem;
        --space-gap: 0.875rem;
    }
    .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; }
}