/* ==========================================================================
   CCYZ.CLOUD - DESIGN SYSTEM & STYLESHEET
   ========================================================================== */

/* 1. 全局设计标记 (Design Tokens) */
:root {
    /* 颜色体系 (Color System) */
    --primary: #10b981;          /* 炫目薄荷/翡翠绿 */
    --primary-hover: #059669;    /* 深薄荷绿 */
    --primary-light: #ecfdf5;    /* 极浅薄荷背景 */
    --secondary: #047857;
    
    --white: #ffffff;
    --gray-50: #f8fafc;
    --gray-100: #f1f5f9;
    --gray-200: #e2e8f0;
    --gray-300: #cbd5e1;
    --gray-400: #94a3b8;
    --gray-600: #475569;
    --gray-700: #334155;
    --gray-800: #1e293b;
    --gray-900: #0f172a;         /* 深炭黑，高对比文字 */
    
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;

    /* 字体 (Typography) */
    --font-heading: 'Outfit', 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    --font-body: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;

    /* 阴影 (Shadows) */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(16, 185, 129, 0.06), 0 4px 6px -4px rgba(16, 185, 129, 0.04);
    --shadow-xl: 0 20px 25px -5px rgba(16, 185, 129, 0.08), 0 8px 10px -6px rgba(16, 185, 129, 0.06);
    --shadow-glow: 0 0 25px rgba(16, 185, 129, 0.35);

    /* 边框圆角 (Border Radius) */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 24px;
    --radius-full: 9999px;

    /* 转换动画 (Transitions) */
    --transition-fast: 0.15s ease;
    --transition-normal: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 2. 基础重置 (Base Resets) */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font-body);
    font-size: 16px;
    line-height: 1.6;
    color: var(--gray-700);
    background-color: var(--white);
    overflow-x: hidden;
}

img, svg {
    display: block;
    max-width: 100%;
}

a {
    color: inherit;
    text-decoration: none;
    transition: var(--transition-fast);
}

button {
    font: inherit;
    background: none;
    border: none;
    cursor: pointer;
}

/* 3. 通用布局容器 (Containers & General Classes) */
.container {
    width: 100%;
    margin-right: auto;
    margin-left: auto;
    padding-right: 20px;
    padding-left: 20px;
}

@media (min-width: 640px) { .container { max-width: 640px; } }
@media (min-width: 768px) { .container { max-width: 768px; } }
@media (min-width: 1024px) { .container { max-width: 1024px; } }
@media (min-width: 1200px) { .container { max-width: 1200px; } }

/* 渐变文字 */
.text-gradient {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

/* 4. 按钮样式 (Buttons System) */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-weight: 600;
    font-family: var(--font-heading);
    border-radius: var(--radius-md);
    transition: var(--transition-normal);
    white-space: nowrap;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: var(--white);
    box-shadow: 0 4px 14px rgba(16, 185, 129, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(16, 185, 129, 0.45);
    background: linear-gradient(135deg, #10c88b 0%, #048b60 100%);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-outline {
    border: 2px solid var(--gray-200);
    background-color: transparent;
    color: var(--gray-800);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background-color: var(--primary-light);
    transform: translateY(-2px);
}

.btn-outline:active {
    transform: translateY(0);
}

.btn-sm {
    padding: 8px 16px;
    font-size: 14px;
}

.btn-lg {
    padding: 14px 32px;
    font-size: 16px;
    border-radius: var(--radius-lg);
}

.btn-block {
    display: flex;
    width: 100%;
}

/* 按钮呼吸动效 */
@keyframes pulse {
    0% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0.4); }
    70% { box-shadow: 0 0 0 10px rgba(16, 185, 129, 0); }
    100% { box-shadow: 0 0 0 0 rgba(16, 185, 129, 0); }
}

.btn-pulse {
    animation: pulse 2s infinite;
}

/* 5. 导航栏样式 (Main Header) */
.main-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background-color: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(241, 245, 249, 0.8);
    transition: var(--transition-normal);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 8px;
}

.logo-text {
    font-size: 22px;
    font-weight: 800;
    font-family: var(--font-heading);
    color: var(--gray-900);
    letter-spacing: -0.5px;
}

.logo-dot {
    color: var(--primary);
}

.nav-menu {
    display: none; /* 移动端优先隐藏，后续在媒体查询中打开 */
    gap: 32px;
}

.nav-link {
    font-weight: 500;
    font-size: 15px;
    color: var(--gray-600);
    position: relative;
    padding: 8px 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--primary);
    transition: var(--transition-fast);
}

.nav-link:hover {
    color: var(--primary);
}

.nav-link:hover::after {
    width: 100%;
}

/* 6. 主视觉区样式 (Hero Section) */
.hero-section {
    position: relative;
    padding-top: 120px;
    padding-bottom: 60px;
    background: radial-gradient(100% 100% at 50% 0%, rgba(236, 253, 245, 0.5) 0%, rgba(255, 255, 255, 1) 100%);
    overflow: hidden;
}

.hero-bg-glow {
    position: absolute;
    top: -100px;
    right: -100px;
    width: 400px;
    height: 400px;
    background: radial-gradient(circle, rgba(16, 185, 129, 0.08) 0%, rgba(16, 185, 129, 0) 70%);
    pointer-events: none;
    z-index: 1;
}

.hero-container {
    position: relative;
    z-index: 2;
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
    align-items: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background-color: var(--primary-light);
    color: var(--primary-hover);
    padding: 6px 14px;
    border-radius: var(--radius-full);
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 24px;
    border: 1px solid rgba(16, 185, 129, 0.15);
    font-family: var(--font-heading);
}

.pulse-dot {
    width: 8px;
    height: 8px;
    background-color: var(--primary);
    border-radius: var(--radius-full);
    position: relative;
}

.pulse-dot::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border-radius: var(--radius-full);
    background-color: var(--primary);
    animation: pulse-ring 1.5s infinite;
}

@keyframes pulse-ring {
    0% { transform: scale(0.95); opacity: 0.8; }
    50% { transform: scale(1.8); opacity: 0; }
    100% { transform: scale(0.95); opacity: 0; }
}

.hero-title {
    font-family: var(--font-heading);
    font-size: 38px;
    line-height: 1.2;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 16px;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: 16px;
    line-height: 1.7;
    color: var(--gray-600);
    margin-bottom: 32px;
    max-width: 540px;
}

.hero-actions {
    display: flex;
    flex-direction: column;
    gap: 16px;
    margin-bottom: 40px;
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: 24px;
}

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

.stat-num {
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 800;
    color: var(--gray-900);
    line-height: 1.1;
}

.stat-label {
    font-size: 12px;
    color: var(--gray-400);
    font-weight: 500;
}

.stat-divider {
    width: 1px;
    height: 32px;
    background-color: var(--gray-200);
}

/* 7. 主视觉卡片与连接网络动画 (Hero Visual Component) */
.hero-visual {
    width: 100%;
    display: flex;
    justify-content: center;
}

.visual-card {
    background-color: var(--white);
    border-radius: var(--radius-xl);
    border: 1px solid rgba(226, 232, 240, 0.8);
    box-shadow: var(--shadow-xl);
    width: 100%;
    max-width: 460px;
    overflow: hidden;
    position: relative;
}

.card-header {
    background-color: var(--gray-50);
    padding: 14px 20px;
    display: flex;
    align-items: center;
    border-bottom: 1px solid var(--gray-100);
}

.header-dots {
    display: flex;
    gap: 6px;
    margin-right: 16px;
}

.header-dots .dot {
    width: 10px;
    height: 10px;
    border-radius: var(--radius-full);
}

.header-dots .dot.red { background-color: #ef4444; }
.header-dots .dot.yellow { background-color: #f59e0b; }
.header-dots .dot.green { background-color: #10b981; }

.header-url {
    font-size: 12px;
    font-family: var(--font-heading);
    color: var(--gray-400);
    font-weight: 500;
}

.card-body {
    padding: 30px;
    background-color: var(--white);
}

.node-network {
    width: 220px;
    height: 220px;
    margin: 0 auto 30px auto;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}

.network-circle {
    position: absolute;
    border: 1.5px dashed rgba(16, 185, 129, 0.12);
    border-radius: var(--radius-full);
}

.network-circle.outer {
    width: 200px;
    height: 200px;
    animation: rotate 40s linear infinite;
}

.network-circle.middle {
    width: 140px;
    height: 140px;
    animation: rotate-reverse 25s linear infinite;
}

.network-circle.inner {
    width: 80px;
    height: 80px;
}

@keyframes rotate {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

@keyframes rotate-reverse {
    from { transform: rotate(360deg); }
    to { transform: rotate(0deg); }
}

.center-node {
    z-index: 5;
    position: relative;
}

.satellite-node {
    position: absolute;
    width: 12px;
    height: 12px;
    background-color: var(--white);
    border: 3px solid var(--primary);
    border-radius: var(--radius-full);
    z-index: 6;
    cursor: pointer;
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.4);
}

.satellite-node::after {
    content: attr(data-label);
    position: absolute;
    top: 18px;
    left: 50%;
    transform: translateX(-50%);
    font-size: 10px;
    font-weight: 700;
    color: var(--gray-600);
    white-space: nowrap;
    background-color: var(--gray-50);
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--gray-200);
}

/* 定义环绕卫星节点的位置 */
.satellite-node.s1 { top: 38px; left: 38px; }
.satellite-node.s2 { top: 28px; right: 48px; }
.satellite-node.s3 { bottom: 38px; right: 38px; }
.satellite-node.s4 { bottom: 28px; left: 48px; }

.network-lines {
    position: absolute;
    top: 10px;
    left: 10px;
    width: 200px;
    height: 200px;
    pointer-events: none;
    z-index: 3;
}

.speedometer-panel {
    background-color: var(--gray-50);
    border-radius: var(--radius-md);
    padding: 16px 20px;
    border: 1px solid var(--gray-100);
}

.speed-indicator {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 10px;
}

.speed-indicator .label {
    font-size: 12px;
    color: var(--gray-400);
    font-weight: 600;
}

.speed-indicator .value {
    font-family: var(--font-heading);
    font-size: 18px;
    font-weight: 800;
    color: var(--gray-900);
}

.speed-indicator .unit {
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
}

.speed-bar {
    width: 100%;
    height: 6px;
    background-color: var(--gray-200);
    border-radius: var(--radius-full);
    overflow: hidden;
}

.speed-bar .fill {
    width: 88%;
    height: 100%;
    background: linear-gradient(90deg, var(--primary) 0%, #34d399 100%);
    border-radius: var(--radius-full);
    animation: speed-glow 2.5s ease-in-out infinite alternate;
}

@keyframes speed-glow {
    0% { width: 75%; }
    50% { width: 92%; }
    100% { width: 85%; }
}

/* 8. 段落标题统一样式 (Section Headers) */
.section-header {
    text-align: center;
    margin-bottom: 48px;
}

.section-tag {
    font-family: var(--font-heading);
    font-size: 13px;
    font-weight: 800;
    color: var(--primary);
    letter-spacing: 2px;
    display: inline-block;
    margin-bottom: 12px;
}

.section-title {
    font-family: var(--font-heading);
    font-size: 28px;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 14px;
    letter-spacing: -0.5px;
}

.section-subtitle {
    font-size: 15px;
    color: var(--gray-600);
    max-width: 600px;
    margin-right: auto;
    margin-left: auto;
}

/* 9. 核心优势部分样式 (Core Features) */
.features-section {
    padding: 80px 0;
    background-color: var(--gray-50);
}

.features-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

.feature-card {
    background-color: var(--white);
    padding: 32px;
    border-radius: var(--radius-lg);
    border: 1px solid rgba(226, 232, 240, 0.6);
    transition: var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(16, 185, 129, 0.2);
}

.card-icon-container {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    background-color: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 24px;
    color: var(--primary);
    transition: var(--transition-normal);
}

.feature-card:hover .card-icon-container {
    background-color: var(--primary);
    color: var(--white);
}

.feature-card:hover .card-icon-container svg path,
.feature-card:hover .card-icon-container svg rect {
    stroke: var(--white);
}
.feature-card:hover .card-icon-container svg path[fill] {
    fill: var(--white);
}

.feature-card .card-title {
    font-size: 18px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 12px;
}

.feature-card .card-desc {
    font-size: 14px;
    line-height: 1.6;
    color: var(--gray-600);
}

/* 10. 套餐价格资费卡片样式 (Pricing Grid) */
.pricing-section {
    padding: 80px 0;
    background-color: var(--white);
}

.pricing-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 32px;
    align-items: flex-start;
}

.price-card {
    background-color: var(--white);
    border-radius: var(--radius-xl);
    border: 2px solid var(--gray-100);
    padding: 40px 30px;
    position: relative;
    transition: var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.price-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: rgba(16, 185, 129, 0.15);
}

/* 重点主力推荐卡片专属样式 */
.price-card.popular {
    border-color: var(--primary);
    box-shadow: var(--shadow-xl);
    background: radial-gradient(100% 100% at 50% 0%, rgba(236, 253, 245, 0.3) 0%, rgba(255, 255, 255, 1) 100%);
}

.popular-badge {
    position: absolute;
    top: -16px;
    left: 50%;
    transform: translateX(-50%);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: var(--white);
    font-size: 11px;
    font-weight: 800;
    padding: 6px 16px;
    border-radius: var(--radius-full);
    letter-spacing: 1px;
    box-shadow: 0 4px 10px rgba(16, 185, 129, 0.35);
    white-space: nowrap;
}

.price-header {
    text-align: center;
    border-bottom: 1px solid var(--gray-100);
    padding-bottom: 24px;
    margin-bottom: 28px;
}

.price-card.popular .price-header {
    border-bottom-color: rgba(16, 185, 129, 0.1);
}

.plan-name {
    font-size: 20px;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 8px;
}

.plan-target {
    font-size: 13px;
    color: var(--gray-400);
    font-weight: 500;
    margin-bottom: 20px;
}

.plan-price {
    display: flex;
    align-items: baseline;
    justify-content: center;
    font-family: var(--font-heading);
}

.plan-price .currency {
    font-size: 20px;
    font-weight: 700;
    color: var(--gray-900);
    margin-right: 4px;
}

.plan-price .amount {
    font-size: 48px;
    font-weight: 800;
    color: var(--gray-900);
    line-height: 1;
}

.plan-price .period {
    font-size: 14px;
    color: var(--gray-400);
    font-weight: 600;
    margin-left: 6px;
}

.price-features {
    margin-bottom: 32px;
}

.price-features ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.price-features li {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--gray-600);
    font-weight: 500;
}

.price-features li svg {
    flex-shrink: 0;
    color: var(--primary);
}

.price-features li svg.cross-icon {
    color: var(--gray-300);
}

.price-features li.muted {
    color: var(--gray-400);
    text-decoration: line-through;
}

.highlight-text {
    color: var(--gray-900);
    font-weight: 700;
}

.price-footer .btn {
    font-size: 15px;
    padding: 12px 24px;
}

.pricing-guarantee {
    text-align: center;
    margin-top: 40px;
    font-size: 13px;
    color: var(--gray-600);
    max-width: 600px;
    margin-right: auto;
    margin-left: auto;
    background-color: var(--gray-50);
    padding: 14px 24px;
    border-radius: var(--radius-md);
    border: 1px dashed var(--gray-200);
}

/* 11. FAQ 常见问题手风琴组件 (FAQ Accordion Details) */
.faq-section {
    padding: 80px 0;
    background-color: var(--gray-50);
}

.faq-accordion-container {
    max-width: 760px;
    margin-right: auto;
    margin-left: auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

/* 现代化 details/summary 手风琴 */
.faq-item {
    background-color: var(--white);
    border-radius: var(--radius-md);
    border: 1px solid rgba(226, 232, 240, 0.8);
    overflow: hidden;
    transition: var(--transition-normal);
}

.faq-item[open] {
    border-color: rgba(16, 185, 129, 0.25);
    box-shadow: var(--shadow-md);
}

.faq-question {
    padding: 20px 24px;
    font-weight: 700;
    font-size: 15px;
    color: var(--gray-900);
    display: flex;
    align-items: center;
    justify-content: space-between;
    list-style: none; /* 去除原生三角 */
    cursor: pointer;
    user-select: none;
    transition: var(--transition-fast);
}

/* 去除 Safari 浏览器默认箭头 */
.faq-question::-webkit-details-marker {
    display: none;
}

.faq-question:hover {
    color: var(--primary);
    background-color: rgba(16, 185, 129, 0.02);
}

.faq-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-400);
    transition: transform var(--transition-normal);
}

.faq-item[open] .faq-icon {
    transform: rotate(180deg);
    color: var(--primary);
}

.faq-answer {
    padding: 0 24px 20px 24px;
    font-size: 14px;
    line-height: 1.7;
    color: var(--gray-600);
    border-top: 1px solid transparent;
    /* 配合简单的展开动画 */
    animation: slide-down 0.25s ease-out;
}

.faq-item[open] .faq-answer {
    border-top-color: var(--gray-100);
}

@keyframes slide-down {
    from { opacity: 0; transform: translateY(-5px); }
    to { opacity: 1; transform: translateY(0); }
}

/* 12. 底部行动呼唤 (Bottom CTA Block) */
.bottom-cta-section {
    padding: 80px 20px;
    position: relative;
    background-color: var(--white);
    overflow: hidden;
}

.bottom-cta-container {
    background: linear-gradient(135deg, var(--gray-900) 0%, #064e3b 100%);
    border-radius: var(--radius-xl);
    padding: 48px 30px;
    text-align: center;
    color: var(--white);
    position: relative;
    z-index: 2;
    box-shadow: var(--shadow-xl);
}

.bottom-cta-glow {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 300px;
    height: 300px;
    background: radial-gradient(circle, rgba(16, 185, 129, 0.15) 0%, rgba(16, 185, 129, 0) 70%);
    pointer-events: none;
    z-index: 1;
}

.bottom-cta-title {
    font-family: var(--font-heading);
    font-size: 26px;
    font-weight: 800;
    margin-bottom: 14px;
    letter-spacing: -0.5px;
}

.bottom-cta-desc {
    font-size: 14px;
    line-height: 1.6;
    color: var(--gray-300);
    max-width: 620px;
    margin-right: auto;
    margin-left: auto;
    margin-bottom: 32px;
}

/* 13. 底部版权信息 (Main Footer) */
.main-footer {
    background-color: var(--gray-900);
    color: var(--gray-400);
    padding: 60px 0 30px 0;
    border-top: 1px solid var(--gray-800);
}

.footer-container {
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
    margin-bottom: 40px;
}

.footer-info .logo {
    margin-bottom: 16px;
}

.footer-info .logo-text {
    color: var(--white);
}

.footer-desc {
    font-size: 14px;
    line-height: 1.6;
    max-width: 360px;
    color: var(--gray-400);
}

.footer-links-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.links-group h4 {
    font-family: var(--font-heading);
    color: var(--white);
    font-size: 15px;
    font-weight: 700;
    margin-bottom: 16px;
    letter-spacing: 0.5px;
}

.links-group a {
    display: block;
    font-size: 13px;
    color: var(--gray-400);
    margin-bottom: 12px;
    transition: var(--transition-fast);
}

.links-group a:hover {
    color: var(--primary);
}

.footer-bottom {
    padding-top: 30px;
    border-top: 1px solid var(--gray-800);
    text-align: center;
}

.copyright {
    font-size: 12px;
    font-weight: 600;
    color: var(--gray-400);
    margin-bottom: 10px;
}

.disclaimer {
    font-size: 11px;
    line-height: 1.5;
    color: var(--gray-600);
}

/* ==========================================================================
   14. 媒体查询与高级自适应 (Responsive Design) - 平板及桌面级
   ========================================================================== */

@media (min-width: 768px) {
    /* 核心字体放大 */
    .hero-title {
        font-size: 52px;
    }
    
    .section-title {
        font-size: 36px;
    }

    /* 优势卡片并排 */
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 28px;
    }

    /* 常见问题提问栏字体略微放大 */
    .faq-question {
        font-size: 16px;
    }

    /* 底部署名版式 */
    .footer-container {
        grid-template-columns: 1.5fr 1fr;
    }
    
    .footer-links-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 40px;
    }
    
    .bottom-cta-container {
        padding: 64px 48px;
    }
    
    .bottom-cta-title {
        font-size: 34px;
    }
    
    .bottom-cta-desc {
        font-size: 16px;
    }
}

@media (min-width: 1024px) {
    /* 导航栏并排显示 */
    .nav-menu {
        display: flex;
    }

    /* 按钮在PC端排列 */
    .hero-actions {
        flex-direction: row;
        gap: 20px;
    }

    /* 主视觉版式左右排版 */
    .hero-container {
        grid-template-columns: 1.1fr 0.9fr;
        gap: 60px;
        padding-top: 40px;
        padding-bottom: 80px;
    }

    .hero-title {
        font-size: 56px;
    }

    .hero-subtitle {
        font-size: 17px;
    }

    /* 优势4卡片全并排 */
    .features-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 24px;
    }

    /* 价格方案 3 栏并排 */
    .pricing-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 30px;
    }

    /* 推荐价格卡片微放大以作视觉强调 */
    .price-card.popular {
        transform: scale(1.03);
        z-index: 10;
    }

    .price-card.popular:hover {
        transform: scale(1.05) translateY(-5px);
    }

    /* 底部落款 */
    .footer-container {
        grid-template-columns: 2fr 1fr;
        gap: 120px;
    }
}

/* ==========================================================================
   15. 丰富页面拓展组件 (Use Cases, Node Matrix, Client Guides, Testimonials)
   ========================================================================== */

/* 15.1 多场景加速支持 (Use Cases Grid) */
.use-cases-section {
    padding: 80px 0;
    background-color: var(--white);
}

.use-cases-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

@media (min-width: 768px) {
    .use-cases-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .use-cases-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.use-case-card {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: 32px;
    transition: var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.use-case-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
    background: var(--white);
}

.use-case-icon {
    width: 52px;
    height: 52px;
    border-radius: var(--radius-md);
    background: var(--primary-light);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
    color: var(--primary);
}

.use-case-title {
    font-size: 19px;
    font-weight: 700;
    font-family: var(--font-heading);
    color: var(--gray-900);
    margin-bottom: 12px;
}

.use-case-desc {
    font-size: 14px;
    line-height: 1.65;
    color: var(--gray-600);
    margin-bottom: 16px;
    flex-grow: 1;
}

.use-case-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.use-case-tag {
    font-size: 12px;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: var(--radius-full);
    background-color: rgba(16, 185, 129, 0.1);
    color: var(--primary-hover);
}

/* 15.2 全球节点延迟与在线状态看板 (Node Status Matrix) */
.nodes-section {
    padding: 80px 0;
    background-color: var(--gray-50);
}

.table-responsive {
    width: 100%;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    background: var(--white);
    border-radius: var(--radius-lg);
    border: 1px solid var(--gray-200);
    box-shadow: var(--shadow-sm);
}

.custom-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
    text-align: left;
    min-width: 650px;
}

.custom-table th {
    background-color: var(--gray-100);
    color: var(--gray-700);
    font-family: var(--font-heading);
    font-weight: 700;
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-200);
    white-space: nowrap;
}

.custom-table td {
    padding: 16px 20px;
    border-bottom: 1px solid var(--gray-100);
    color: var(--gray-700);
    vertical-align: middle;
}

.custom-table tr:last-child td {
    border-bottom: none;
}

.custom-table tr:hover td {
    background-color: var(--primary-light);
}

.region-cell {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 600;
    color: var(--gray-900);
}

.flag-icon {
    font-size: 18px;
    display: inline-block;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 12px;
    font-weight: 600;
    padding: 4px 10px;
    border-radius: var(--radius-full);
}

.badge-success {
    background-color: #dcfce7;
    color: #15803d;
}

.badge-primary {
    background-color: var(--primary-light);
    color: var(--secondary);
}

.badge-outline {
    border: 1px solid var(--gray-300);
    color: var(--gray-600);
}

/* 15.3 全平台客户端生态 (Clients Grid) */
.clients-section {
    padding: 80px 0;
    background-color: var(--white);
}

.clients-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

@media (min-width: 640px) {
    .clients-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .clients-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

.client-card {
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: 28px 24px;
    text-align: center;
    background: var(--white);
    transition: var(--transition-normal);
}

.client-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
}

.client-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto 16px;
    background: var(--gray-100);
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--gray-800);
}

.client-card:hover .client-icon {
    background: var(--primary-light);
    color: var(--primary);
}

.client-name {
    font-size: 18px;
    font-weight: 700;
    font-family: var(--font-heading);
    color: var(--gray-900);
    margin-bottom: 8px;
}

.client-software {
    font-size: 13px;
    color: var(--gray-500);
    margin-bottom: 16px;
    line-height: 1.5;
}

.client-link {
    font-size: 13px;
    font-weight: 600;
    color: var(--primary);
    display: inline-flex;
    align-items: center;
    gap: 4px;
}

.client-link:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* 15.4 用户口碑真实评测 (Testimonials Grid) */
.testimonials-section {
    padding: 80px 0;
    background-color: var(--gray-50);
}

.testimonials-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 24px;
}

@media (min-width: 768px) {
    .testimonials-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.testimonial-card {
    background: var(--white);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: 28px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.testimonial-stars {
    color: #f59e0b;
    margin-bottom: 12px;
    display: flex;
    gap: 3px;
}

.testimonial-quote {
    font-size: 14px;
    line-height: 1.7;
    color: var(--gray-700);
    margin-bottom: 20px;
    flex-grow: 1;
}

.testimonial-author {
    display: flex;
    align-items: center;
    gap: 12px;
}

.author-avatar {
    width: 42px;
    height: 42px;
    border-radius: var(--radius-full);
    background: var(--primary-light);
    color: var(--primary-hover);
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 15px;
}

.author-info h4 {
    font-size: 14px;
    font-weight: 700;
    color: var(--gray-900);
}

.author-info p {
    font-size: 12px;
    color: var(--gray-400);
}

/* 15.5 首页技术博客与指南专区 (Blog Preview Grid) */
.blog-section {
    padding: 80px 0;
    background-color: var(--white);
}

.blog-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: 28px;
}

@media (min-width: 768px) {
    .blog-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    .blog-grid {
        grid-template-columns: repeat(3, 1fr);
    }
}

.blog-card {
    background: var(--white);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    overflow: hidden;
    transition: var(--transition-normal);
    display: flex;
    flex-direction: column;
}

.blog-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary);
}

.blog-card-body {
    padding: 24px;
    display: flex;
    flex-direction: column;
    flex-grow: 1;
}

.blog-card-meta {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 12px;
    color: var(--gray-400);
    margin-bottom: 12px;
}

.blog-card-tag {
    color: var(--primary-hover);
    background-color: var(--primary-light);
    font-weight: 600;
    padding: 2px 8px;
    border-radius: var(--radius-sm);
}

.blog-card-title {
    font-family: var(--font-heading);
    font-size: 18px;
    font-weight: 700;
    color: var(--gray-900);
    line-height: 1.4;
    margin-bottom: 10px;
    transition: var(--transition-fast);
}

.blog-card:hover .blog-card-title {
    color: var(--primary);
}

.blog-card-excerpt {
    font-size: 14px;
    line-height: 1.6;
    color: var(--gray-600);
    margin-bottom: 16px;
    flex-grow: 1;
}

.blog-card-link {
    font-size: 14px;
    font-weight: 600;
    color: var(--primary);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: auto;
}

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

/* ==========================================================================
   16. 文章与教程专用排版系统 (Articles & SEO Long-form Typography)
   ========================================================================== */

.page-header-gap {
    height: 72px;
}

.article-hero {
    background: radial-gradient(100% 100% at 50% 0%, rgba(236, 253, 245, 0.6) 0%, rgba(255, 255, 255, 1) 100%);
    padding: 48px 0 32px 0;
    border-bottom: 1px solid var(--gray-200);
}

.breadcrumb-nav {
    margin-bottom: 20px;
}

.breadcrumb-list {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
    list-style: none;
    font-size: 13px;
    color: var(--gray-500);
}

.breadcrumb-list a {
    color: var(--gray-600);
}

.breadcrumb-list a:hover {
    color: var(--primary);
}

.breadcrumb-separator {
    color: var(--gray-400);
}

.article-title-main {
    font-family: var(--font-heading);
    font-size: 28px;
    line-height: 1.3;
    font-weight: 800;
    color: var(--gray-900);
    margin-bottom: 16px;
    letter-spacing: -0.5px;
}

@media (min-width: 768px) {
    .article-title-main {
        font-size: 38px;
    }
}

.article-meta-bar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 16px;
    font-size: 13px;
    color: var(--gray-500);
}

.article-meta-item {
    display: flex;
    align-items: center;
    gap: 6px;
}

.article-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 40px;
    padding: 48px 0 80px 0;
}

@media (min-width: 1024px) {
    .article-layout {
        grid-template-columns: 1fr 300px;
        align-items: start;
    }
}

.article-main {
    background: var(--white);
    max-width: 100%;
}

.article-body {
    font-size: 16px;
    line-height: 1.85;
    color: var(--gray-800);
}

.article-body h2 {
    font-family: var(--font-heading);
    font-size: 24px;
    font-weight: 800;
    color: var(--gray-900);
    margin-top: 40px;
    margin-bottom: 18px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--gray-100);
    letter-spacing: -0.3px;
    scroll-margin-top: 90px;
}

.article-body h3 {
    font-family: var(--font-heading);
    font-size: 19px;
    font-weight: 700;
    color: var(--gray-900);
    margin-top: 28px;
    margin-bottom: 14px;
    padding-left: 12px;
    border-left: 4px solid var(--primary);
    scroll-margin-top: 90px;
}

.article-body p {
    margin-bottom: 20px;
}

.article-body ul, .article-body ol {
    margin-bottom: 22px;
    padding-left: 24px;
}

.article-body li {
    margin-bottom: 8px;
    line-height: 1.75;
}

.article-body strong {
    color: var(--gray-900);
    font-weight: 700;
}

.article-body a {
    color: var(--primary);
    text-decoration: underline;
    text-underline-offset: 3px;
    transition: color 0.2s;
}

.article-body a:hover {
    color: var(--primary-hover);
}

/* 提示警示框 (Callout Box) */
.callout-box {
    padding: 20px 24px;
    border-radius: var(--radius-md);
    margin: 24px 0;
    display: flex;
    gap: 16px;
    background-color: var(--gray-50);
    border-left: 4px solid var(--primary);
}

.callout-box.info {
    background-color: #f0fdf4;
    border-left-color: var(--primary);
}

.callout-box.warning {
    background-color: #fffbeb;
    border-left-color: var(--warning);
}

.callout-box.tip {
    background-color: #eff6ff;
    border-left-color: #3b82f6;
}

.callout-icon {
    font-size: 22px;
    flex-shrink: 0;
}

.callout-content {
    font-size: 14px;
    line-height: 1.65;
    color: var(--gray-700);
}

.callout-content strong {
    display: block;
    font-size: 15px;
    color: var(--gray-900);
    margin-bottom: 4px;
}

/* 侧边栏及文章目录 (Sidebar & TOC) */
.article-sidebar {
    position: sticky;
    top: 90px;
    display: flex;
    flex-direction: column;
    gap: 28px;
}

.sidebar-widget {
    background: var(--gray-50);
    border: 1px solid var(--gray-200);
    border-radius: var(--radius-lg);
    padding: 24px;
}

.widget-title {
    font-family: var(--font-heading);
    font-size: 16px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 14px;
    padding-bottom: 8px;
    border-bottom: 1px solid var(--gray-200);
}

.toc-list {
    list-style: none;
    padding-left: 0;
    display: flex;
    flex-direction: column;
    gap: 10px;
    font-size: 13px;
}

.toc-list a {
    color: var(--gray-600);
    line-height: 1.4;
    transition: color 0.2s;
    display: block;
}

.toc-list a:hover {
    color: var(--primary);
    padding-left: 4px;
}

.toc-list .toc-sub {
    padding-left: 14px;
    color: var(--gray-500);
}

/* 侧边栏转化卡片 */
.sidebar-cta-widget {
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    border-radius: var(--radius-lg);
    padding: 24px;
    color: var(--white);
    text-align: center;
}

.sidebar-cta-title {
    font-family: var(--font-heading);
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

.sidebar-cta-desc {
    font-size: 13px;
    color: var(--gray-400);
    margin-bottom: 18px;
    line-height: 1.5;
}

/* 标签与相关推荐 */
.article-footer-tags {
    margin-top: 40px;
    padding-top: 24px;
    border-top: 1px solid var(--gray-200);
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 8px;
}

.tag-label {
    font-size: 13px;
    font-weight: 600;
    color: var(--gray-600);
}

.article-tag {
    font-size: 12px;
    color: var(--primary-hover);
    background-color: var(--primary-light);
    padding: 4px 10px;
    border-radius: var(--radius-full);
}

.article-author-card {
    margin-top: 32px;
    padding: 24px;
    background: var(--gray-50);
    border-radius: var(--radius-lg);
    border: 1px solid var(--gray-200);
    display: flex;
    align-items: center;
    gap: 16px;
}

.author-large-avatar {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-full);
    background: var(--primary);
    color: var(--white);
    font-weight: 800;
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.author-large-info h4 {
    font-size: 16px;
    font-weight: 700;
    color: var(--gray-900);
    margin-bottom: 4px;
}

.author-large-info p {
    font-size: 13px;
    color: var(--gray-600);
    margin-bottom: 0;
}