:root {
    --color-primary: #0f172a;
    --color-primary-dark: #020617;
    --color-accent: #3b82f6;
    --color-surface: #f8fafc;
    --color-text: #0b1220;

    --rgb-primary: 15,23,42;
    --rgb-accent: 59,130,246;

    --radius-sm: 8px;
    --radius-md: 14px;
    --radius-lg: 18px;
    --radius-xl: 26px;

    --shadow-sm: 0 1px 0 rgba(2,6,23,.18), 0 6px 18px rgba(15,23,42,.10);
    --shadow-md: 0 2px 0 rgba(2,6,23,.10), 0 10px 26px rgba(15,23,42,.16), 0 0 0 1px rgba(148,163,184,.18) inset;
    --shadow-lg: 0 2px 0 rgba(2,6,23,.12), 0 18px 42px rgba(15,23,42,.22), 0 0 0 1px rgba(148,163,184,.22) inset, 0 0 26px rgba(59,130,246,.14);

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

    --transition: 0.55s cubic-bezier(0.2, 0.9, 0.2, 1);
    --heading-weight: 700;
    --body-line-height: 1.65;

    --card-bg: linear-gradient(180deg, rgba(255,255,255,.92) 0%, rgba(248,250,252,.98) 100%);
    --card-edge: linear-gradient(90deg, rgba(59,130,246,.55) 0%, rgba(148,163,184,.35) 45%, rgba(59,130,246,.20) 100%);
    --focus-ring: 0 0 0 4px rgba(59,130,246,.22), 0 0 0 1px rgba(59,130,246,.45);
}

body {
    color: var(--color-text);
    line-height: var(--body-line-height);
    background:
        radial-gradient(1200px 600px at 12% -10%, rgba(59,130,246,.18) 0%, rgba(59,130,246,0) 60%),
        radial-gradient(900px 520px at 92% 0%, rgba(148,163,184,.20) 0%, rgba(148,163,184,0) 55%),
        linear-gradient(180deg, #0b1220 0%, #0f172a 48%, #0b1220 100%);
    background-attachment: fixed;
}

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);
    background: var(--card-bg);
    box-shadow: var(--shadow-md);
    padding: var(--space-card);
    transition:
        transform var(--transition),
        box-shadow var(--transition),
        background var(--transition),
        border-color var(--transition),
        filter var(--transition),
        opacity var(--transition);
    border-style: solid;
    border-width: 1px;
    border-color: rgba(148,163,184,.26);
    outline: 1px solid rgba(59,130,246,.10);
    outline-offset: -1px;
}

.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition:
        transform var(--transition),
        box-shadow var(--transition),
        background var(--transition),
        border-color var(--transition),
        color var(--transition),
        filter var(--transition);
    box-shadow: 0 10px 24px rgba(2,6,23,.12), 0 0 0 1px rgba(148,163,184,.18) inset;
    border-style: solid;
    border-width: 1px;
    border-color: rgba(148,163,184,.24);
    background:
        linear-gradient(135deg, rgba(255,255,255,.92) 0%, rgba(248,250,252,.96) 45%, rgba(226,232,240,.92) 100%);
    color: #0b1220;
}

a:not([class]) {
    color: #dbeafe;
    transition: var(--transition);
    text-shadow: 0 1px 0 rgba(0,0,0,.18);
}

a:not([class]):hover { color: var(--color-accent); }

.cta-section {
    background:
        radial-gradient(900px 460px at 10% 0%, rgba(59,130,246,.55) 0%, rgba(59,130,246,0) 60%),
        radial-gradient(760px 420px at 90% 20%, rgba(148,163,184,.35) 0%, rgba(148,163,184,0) 62%),
        linear-gradient(180deg, #0b3a7a 0%, #0f172a 100%);
    color: #f8fafc;
    padding: 4rem 2rem;

    border-style: solid;
    border-width: 1px;
    border-color: rgba(148,163,184,.22);
    box-shadow:
        0 1px 0 rgba(255,255,255,.06) inset,
        0 18px 60px rgba(2,6,23,.55),
        0 0 0 1px rgba(59,130,246,.18) inset;
    overflow: hidden;
    position: relative;
}

.news-grid { display: flex; flex-direction: column; gap: var(--space-gap); }
.news-grid .card { display: grid; grid-template-columns: 280px 1fr; }

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

.hero-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 2rem; align-items: center; }

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

.partner-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: calc(var(--space-gap) * 1.5); align-items: center; }

.faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 2rem; }

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

.page-main { max-width: 860px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover,
[class*="card"]:hover {
    transform: translateY(-5px);
    box-shadow:
        0 2px 0 rgba(2,6,23,.12),
        0 26px 60px rgba(2,6,23,.28),
        0 0 0 1px rgba(59,130,246,.30) inset,
        0 0 46px rgba(59,130,246,.20);
    filter: saturate(1.05) contrast(1.02);
    outline: 1px solid rgba(59,130,246,.26);
    outline-offset: -1px;
    opacity: .98;
}

.card { border: 1px solid rgba(59,130,246,.22); }

@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;

        --radius-sm: 7px;
        --radius-md: 12px;
        --radius-lg: 16px;
    }
    .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; }
}