/* ===== 基础变量与重置 ===== */
:root {
    --primary: #10b981;
    --primary-dark: #059669;
    --primary-soft: #d1fae5;
    --primary-light: #ecfdf5;
    --slate-900: #0f172a;
    --slate-800: #1e293b;
    --slate-700: #334155;
    --slate-500: #64748b;
    --slate-300: #cbd5e1;
    --slate-100: #f1f5f9;
    --white: #ffffff;
    --radius-lg: 16px;
    --radius-md: 12px;
    --radius-sm: 8px;
    --shadow-card: 0 4px 6px -1px rgba(0,0,0,0.05), 0 2px 4px -2px rgba(0,0,0,0.05);
    --shadow-hover: 0 10px 15px -3px rgba(5,150,105,0.08), 0 4px 6px -4px rgba(5,150,105,0.04);
    --transition: 0.2s ease;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'Noto Sans', sans-serif;
    color: var(--slate-800);
    line-height: 1.6;
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
}

/* ===== 头部导航 ===== */
header {
    position: sticky;
    top: 0;
    background: rgba(255,255,255,0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--slate-300);
    z-index: 1000;
}

.header-box {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 24px;
    gap: 20px;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    text-decoration: none;
    color: var(--slate-900);
    font-weight: 700;
    font-size: 1.35rem;
    letter-spacing: -0.3px;
    white-space: nowrap;
}

.brand-logo img {
    width: 36px;
    height: 36px;
}

nav {
    display: flex;
    align-items: center;
    gap: 28px;
    flex-wrap: wrap;
}

nav a {
    text-decoration: none;
    color: var(--slate-700);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color var(--transition);
    white-space: nowrap;
}

nav a:hover {
    color: var(--primary-dark);
}

nav a.current-tab {
    color: var(--primary);
    font-weight: 600;
    border-bottom: 2px solid var(--primary);
    padding-bottom: 4px;
}

.nav-accent {
    background-color: var(--primary);
    color: white !important;
    padding: 8px 18px;
    border-radius: 20px;
    font-size: 0.9rem;
    transition: background-color var(--transition);
}

.nav-accent:hover {
    background-color: var(--primary-dark);
    color: white !important;
}

/* ===== Hero 区域 ===== */
.hero-section {
    padding: 70px 24px 60px;
    text-align: center;
    background: linear-gradient(180deg, #f8fafc 0%, #ffffff 100%);
}

.hero-wrapper {
    max-width: 880px;
    margin: 0 auto;
}

.hero-badge {
    display: inline-block;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 6px 18px;
    border-radius: 20px;
    margin-bottom: 24px;
    letter-spacing: 0.3px;
}

.hero-wrapper h1 {
    font-size: clamp(2rem, 5vw, 2.8rem);
    color: var(--slate-900);
    line-height: 1.3;
    margin-bottom: 20px;
    letter-spacing: -0.6px;
}

.hero-desc {
    font-size: 1.15rem;
    color: var(--slate-500);
    max-width: 700px;
    margin: 0 auto 36px;
    line-height: 1.7;
}

.hero-actions {
    display: flex;
    gap: 16px;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 48px;
}

.btn-primary {
    background: var(--primary);
    color: white;
    padding: 14px 32px;
    border-radius: 40px;
    font-weight: 600;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    transition: background var(--transition), transform 0.15s ease;
    box-shadow: 0 4px 6px rgba(16,185,129,0.25);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: var(--slate-800);
    padding: 14px 32px;
    border-radius: 40px;
    font-weight: 600;
    text-decoration: none;
    border: 1.5px solid var(--slate-300);
    transition: border-color var(--transition), color var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary-dark);
}

.hero-stats {
    display: flex;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.stat-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.stat-item strong {
    font-size: 1.8rem;
    color: var(--primary);
    font-weight: 800;
    line-height: 1.2;
}

.stat-item span {
    font-size: 0.9rem;
    color: var(--slate-500);
    margin-top: 4px;
}

/* ===== 通用区块容器 ===== */
.section-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

section {
    padding: 80px 0;
}

section h2 {
    font-size: 2rem;
    color: var(--slate-900);
    margin-bottom: 16px;
    letter-spacing: -0.4px;
    text-align: center;
    position: relative;
}

section h2::after {
    content: '';
    display: block;
    width: 50px;
    height: 4px;
    background: var(--primary);
    margin: 16px auto 0;
    border-radius: 2px;
}

.section-lead {
    text-align: center;
    color: var(--slate-500);
    font-size: 1.1rem;
    max-width: 650px;
    margin: 0 auto 48px;
    line-height: 1.6;
}

/* ===== 多平台下载矩阵 ===== */
.section-download-matrix {
    background: var(--slate-100);
    padding: 80px 0;
}

.platform-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 24px;
}

.platform-card {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 28px 20px;
    text-align: center;
    transition: box-shadow var(--transition), transform var(--transition);
}

.platform-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
}

.platform-icon {
    font-size: 2.4rem;
    margin-bottom: 12px;
}

.platform-card h3 {
    font-size: 1.2rem;
    color: var(--slate-800);
    margin-bottom: 8px;
}

.platform-card p {
    font-size: 0.9rem;
    color: var(--slate-500);
    margin-bottom: 16px;
    line-height: 1.5;
}

.card-link {
    display: inline-block;
    color: var(--primary);
    font-weight: 600;
    text-decoration: none;
    font-size: 0.9rem;
    border-bottom: 1px solid transparent;
    transition: border-color var(--transition);
}

.card-link:hover {
    border-bottom-color: var(--primary);
}

/* ===== 三步部署 ===== */
.steps-row {
    display: flex;
    gap: 24px;
    justify-content: center;
    flex-wrap: wrap;
}

.step-block {
    flex: 1 1 250px;
    max-width: 330px;
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 32px 24px;
    position: relative;
}

.step-num {
    display: inline-block;
    background: var(--primary-soft);
    color: var(--primary-dark);
    font-weight: 800;
    font-size: 1rem;
    padding: 6px 14px;
    border-radius: 20px;
    margin-bottom: 16px;
}

.step-block h3 {
    font-size: 1.2rem;
    color: var(--slate-800);
    margin-bottom: 10px;
}

.step-block p {
    font-size: 0.95rem;
    color: var(--slate-500);
    line-height: 1.6;
}

.step-block a {
    color: var(--primary);
    font-weight: 600;
    text-decoration: none;
}

.step-block a:hover {
    text-decoration: underline;
}

/* ===== 规则分流预览 ===== */
.rules-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    margin-bottom: 40px;
}

.rule-item {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 24px;
    transition: box-shadow var(--transition);
}

.rule-item:hover {
    box-shadow: var(--shadow-hover);
}

.rule-item h3 {
    font-size: 1.1rem;
    color: var(--slate-800);
    margin-bottom: 8px;
}

.rule-item p {
    font-size: 0.95rem;
    color: var(--slate-500);
    line-height: 1.6;
}

code {
    background: var(--slate-100);
    padding: 2px 8px;
    border-radius: 4px;
    font-family: 'Fira Code', monospace;
    font-size: 0.85rem;
}

.center-btn {
    display: table;
    margin: 0 auto;
}

/* ===== 配置指南亮点 ===== */
.guide-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}

.guide-card {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 28px 20px;
    text-decoration: none;
    color: inherit;
    transition: box-shadow var(--transition), transform var(--transition);
    display: block;
}

.guide-card:hover {
    box-shadow: var(--shadow-hover);
    transform: translateY(-3px);
}

.guide-card h3 {
    font-size: 1.15rem;
    color: var(--slate-800);
    margin-bottom: 8px;
}

.guide-card p {
    font-size: 0.9rem;
    color: var(--slate-500);
    line-height: 1.5;
}

/* ===== 适用场景 ===== */
.scenario-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
}

.scenario-card {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 28px 20px;
}

.scenario-card h3 {
    font-size: 1.2rem;
    margin-bottom: 10px;
    color: var(--slate-800);
}

.scenario-card p {
    font-size: 0.95rem;
    color: var(--slate-500);
    line-height: 1.6;
}

/* ===== 信任指标 ===== */
.section-trust {
    background: var(--slate-100);
}

.trust-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
}

.trust-item {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: var(--radius-lg);
    padding: 24px;
    text-align: center;
}

.trust-item strong {
    display: block;
    font-size: 1.1rem;
    color: var(--slate-800);
    margin-bottom: 8px;
}

.trust-item p {
    font-size: 0.9rem;
    color: var(--slate-500);
}

/* ===== 常见问题快捷入口 ===== */
.faq-quick-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 16px;
    margin-bottom: 36px;
}

.faq-quick-item {
    background: var(--white);
    border: 1px solid var(--slate-300);
    border-radius: 30px;
    padding: 14px 22px;
    text-decoration: none;
    color: var(--slate-700);
    font-weight: 500;
    transition: background var(--transition), border-color var(--transition);
    text-align: center;
}

.faq-quick-item:hover {
    background: var(--primary-light);
    border-color: var(--primary);
    color: var(--primary-dark);
}

/* ===== 底部 ===== */
footer {
    background: var(--slate-900);
    color: #94a3b8;
    padding: 60px 24px 30px;
    border-top: 4px solid var(--primary);
}

.footer-wrapper {
    max-width: 1100px;
    margin: 0 auto;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 36px;
    border-bottom: 1px solid var(--slate-700);
    padding-bottom: 36px;
    margin-bottom: 28px;
}

.footer-section h5 {
    color: white;
    font-size: 1rem;
    margin-bottom: 20px;
    font-weight: 600;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 12px;
}

.footer-section ul li a {
    color: #94a3b8;
    text-decoration: none;
    font-size: 0.9rem;
    transition: color var(--transition);
}

.footer-section ul li a:hover {
    color: var(--primary);
}

.footer-legal {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
    font-size: 0.85rem;
    color: #64748b;
}

/* ===== 响应式调整 ===== */
@media (max-width: 800px) {
    .header-box {
        flex-direction: column;
        gap: 16px;
    }
    nav {
        justify-content: center;
        gap: 20px;
    }
    .hero-stats {
        gap: 24px;
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-legal {
        flex-direction: column;
        text-align: center;
    }
}

@media (max-width: 500px) {
    .hero-actions {
        flex-direction: column;
        align-items: center;
    }
    .footer-grid {
        grid-template-columns: 1fr;
    }
    section {
        padding: 60px 0;
    }
    section h2 {
        font-size: 1.6rem;
    }
}