/* ==========================================================================
   肯の基 (kfc-jc.lat) - 统一视觉设计与现代样式表
   风格：科技极简风（深色背景、单一黄色/琥珀高质感强调色、轻量动态、数字化利落）
   编码：UTF-8 | 原生 CSS | 响应式 | 无障碍优先 | 尊重减少动态效果设置
   ========================================================================== */

:root {
  --font-main: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --font-heading: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  
  /* 黑白灰深色极简基底 */
  --bg-primary: #090a0d;
  --bg-secondary: #111318;
  --bg-card: rgba(18, 20, 26, 0.82);
  --bg-card-hover: rgba(26, 29, 38, 0.95);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-medium: rgba(255, 255, 255, 0.16);
  
  /* 科技单一强调色：数字琥珀黄 */
  --accent-color: #f59e0b;
  --accent-light: #fbbf24;
  --accent-dark: #d97706;
  --accent-bg: rgba(245, 158, 11, 0.1);
  --accent-border: rgba(245, 158, 11, 0.32);
  --accent-glow: rgba(245, 158, 11, 0.22);

  /* 文字颜色 */
  --text-primary: #f8fafc;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  --text-dim: #64748b;

  /* 弹窗专用 */
  --modal-bg: #ffffff;
  --modal-text-title: #0f172a;
  --modal-text-body: #334155;
  --modal-border: #e2e8f0;

  /* 常用圆角与过渡 */
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-pill: 999px;
  --transition-fast: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-smooth: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

/* 尊重减少动态效果设置 */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

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

html {
  font-family: var(--font-main);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  background: radial-gradient(circle at 50% 0%, #151822 0%, #090a0d 65%);
}

body.modal-open {
  overflow: hidden;
}

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

img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ==========================================================================
   页面顶部导航 (Header & Navbar)
   ========================================================================== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(9, 10, 13, 0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-subtle);
  width: 100%;
}

.header-container {
  max-width: 1160px;
  margin: 0 auto;
  padding: 0.85rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-heading);
  font-size: 1.3rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  color: #ffffff;
  cursor: pointer;
}

.brand-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  background: #181b22;
  border: 1px solid var(--accent-border);
  color: var(--accent-color);
  font-size: 1.1rem;
  font-weight: 900;
  box-shadow: 0 0 12px var(--accent-glow);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  list-style: none;
}

.nav-link {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color var(--transition-fast);
  padding: 0.25rem 0.4rem;
}

.nav-link:hover, .nav-link.active {
  color: #ffffff;
}

.nav-link.highlight {
  color: var(--accent-light);
  font-weight: 600;
}

.header-cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.5rem 1.15rem;
  font-size: 0.86rem;
  font-weight: 700;
  color: #000000;
  background: var(--accent-color);
  border-radius: var(--radius-pill);
  box-shadow: 0 2px 10px var(--accent-glow);
  transition: transform var(--transition-fast), background var(--transition-fast), box-shadow var(--transition-fast);
  cursor: pointer;
  white-space: nowrap;
}

.header-cta:hover {
  background: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(245, 158, 11, 0.4);
}

/* ==========================================================================
   页面主要内容容器
   ========================================================================== */
.main-wrapper {
  flex: 1;
  width: 100%;
  max-width: 1160px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 5rem;
}

/* ==========================================================================
   主视觉英雄区 (Hero Section - 桌面端图文卡片排布，手机端上下排列)
   ========================================================================== */
.hero-section {
  padding: 3.5rem 0 4rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  align-items: center;
  gap: 3rem;
}

.hero-text-content {
  text-align: left;
}

.badge-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-pill);
  background: var(--accent-bg);
  border: 1px solid var(--accent-border);
  color: var(--accent-light);
  font-size: 0.82rem;
  font-weight: 600;
  margin-bottom: 1.25rem;
}

.badge-dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background-color: var(--accent-color);
  box-shadow: 0 0 8px var(--accent-color);
}

.hero-title {
  font-family: var(--font-heading);
  font-size: clamp(2.1rem, 4vw, 3.4rem);
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.02em;
  color: #ffffff;
  margin-bottom: 1.25rem;
}

.hero-subtitle {
  font-size: clamp(0.95rem, 1.6vw, 1.12rem);
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 1.5rem;
}

.hero-disclaimer-note {
  display: inline-block;
  font-size: 0.82rem;
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.03);
  padding: 0.4rem 0.85rem;
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border-subtle);
  margin-bottom: 2rem;
}

.hero-actions {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.85rem 2.2rem;
  font-size: 1rem;
  font-weight: 700;
  color: #000000;
  background: var(--accent-color);
  border-radius: var(--radius-pill);
  box-shadow: 0 4px 16px var(--accent-glow);
  transition: transform var(--transition-fast), background var(--transition-fast), box-shadow var(--transition-fast);
  cursor: pointer;
  border: none;
  white-space: nowrap;
}

.btn-primary:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(245, 158, 11, 0.45);
}

.btn-secondary {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.85rem 1.6rem;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  background: #181b22;
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-pill);
  transition: background var(--transition-fast), border-color var(--transition-fast);
  white-space: nowrap;
}

.btn-secondary:hover {
  background: #232732;
  border-color: rgba(255, 255, 255, 0.3);
}

/* Hero 右侧动态卡片展示 */
.hero-visual-card {
  background: linear-gradient(145deg, rgba(24, 27, 36, 0.9), rgba(14, 16, 21, 0.95));
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.5);
  position: relative;
  overflow: hidden;
}

.hero-visual-card::before {
  content: "";
  position: absolute;
  top: -40px;
  right: -40px;
  width: 140px;
  height: 140px;
  background: var(--accent-glow);
  filter: blur(40px);
  border-radius: 50%;
  pointer-events: none;
}

.visual-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.5rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

.visual-status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.75rem;
  font-weight: 600;
  color: #10b981;
  background: rgba(16, 185, 129, 0.12);
  padding: 0.25rem 0.65rem;
  border-radius: var(--radius-pill);
}

.visual-status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background-color: #10b981;
  box-shadow: 0 0 6px #10b981;
}

.visual-metric-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.metric-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.88rem;
  color: var(--text-secondary);
  background: rgba(255, 255, 255, 0.02);
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-subtle);
}

.metric-value {
  font-weight: 700;
  color: #ffffff;
}

/* ==========================================================================
   内容分块通用基础样式
   ========================================================================== */
.content-section {
  padding: 4rem 0;
  border-top: 1px solid var(--border-subtle);
}

.section-header {
  text-align: center;
  margin-bottom: 2.75rem;
}

.section-label {
  display: inline-block;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--accent-color);
  margin-bottom: 0.5rem;
}

.section-title {
  font-family: var(--font-heading);
  font-size: clamp(1.6rem, 2.5vw, 2.1rem);
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 0.75rem;
}

.section-desc {
  font-size: 0.95rem;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
}

/* ==========================================================================
   核心优势卡片区 (Features Grid - 3到6个图文卡片)
   ========================================================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.85rem 1.5rem;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-fast), border-color var(--transition-fast), background var(--transition-fast);
}

.feature-card:hover {
  transform: translateY(-3px);
  background: var(--bg-card-hover);
  border-color: var(--border-medium);
}

.feature-icon-wrapper {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--accent-bg);
  border: 1px solid var(--accent-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.35rem;
  color: var(--accent-color);
  margin-bottom: 1.15rem;
}

.feature-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.65rem;
}

.feature-text {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ==========================================================================
   流媒体与 AI 支持模块 (Streaming & AI Support)
   ========================================================================== */
.support-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
}

.support-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  transition: border-color var(--transition-fast);
}

.support-card:hover {
  border-color: var(--border-medium);
}

.support-badge-group {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin-bottom: 0.25rem;
}

.support-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.1rem;
}

.support-name {
  font-size: 1.05rem;
  font-weight: 700;
  color: #ffffff;
}

.support-desc {
  font-size: 0.88rem;
  color: var(--text-secondary);
  line-height: 1.55;
}

.support-condition-note {
  font-size: 0.78rem;
  color: var(--text-muted);
  background: rgba(0, 0, 0, 0.25);
  padding: 0.35rem 0.6rem;
  border-radius: var(--radius-sm);
  border-left: 2px solid var(--accent-color);
}

/* ==========================================================================
   套餐对比区域 (Pricing Comparison)
   ========================================================================== */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.pricing-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.25rem 1.75rem;
  display: flex;
  flex-direction: column;
  position: relative;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.pricing-card.popular {
  border-color: var(--accent-border);
  background: linear-gradient(180deg, rgba(26, 29, 38, 0.95), rgba(18, 20, 26, 0.95));
}

.pricing-card:hover {
  transform: translateY(-4px);
  border-color: var(--border-medium);
}

.pricing-popular-tag {
  position: absolute;
  top: -12px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--accent-color);
  color: #000000;
  font-size: 0.75rem;
  font-weight: 800;
  padding: 0.25rem 0.85rem;
  border-radius: var(--radius-pill);
}

.pricing-plan-name {
  font-size: 1.25rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 0.5rem;
}

.pricing-plan-desc {
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 1.25rem;
}

.pricing-meta-box {
  background: rgba(255, 255, 255, 0.03);
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  margin-bottom: 1.5rem;
  border: 1px solid var(--border-subtle);
}

.pricing-meta-row {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-secondary);
  padding: 0.25rem 0;
}

.pricing-meta-val {
  font-weight: 600;
  color: #ffffff;
}

.pricing-features-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  margin-bottom: 2rem;
  flex: 1;
}

.pricing-feature-item {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.pricing-check-icon {
  color: var(--accent-light);
  font-weight: 900;
}

.pricing-btn {
  display: block;
  width: 100%;
  text-align: center;
  padding: 0.85rem 1.25rem;
  font-size: 0.95rem;
  font-weight: 700;
  color: #000000;
  background: var(--accent-color);
  border-radius: var(--radius-pill);
  transition: background var(--transition-fast), transform var(--transition-fast);
}

.pricing-btn:hover {
  background: var(--accent-light);
  transform: translateY(-2px);
}

.pricing-disclaimer {
  text-align: center;
  font-size: 0.82rem;
  color: var(--text-muted);
  margin-top: 1.5rem;
}

/* ==========================================================================
   常见问题区 (FAQ Section)
   ========================================================================== */
.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
}

.faq-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.5rem;
}

.faq-question {
  font-size: 1.05rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.6rem;
  display: flex;
  align-items: flex-start;
  gap: 0.5rem;
}

.faq-question span.q-badge {
  color: var(--accent-color);
  font-weight: 800;
}

.faq-answer {
  font-size: 0.92rem;
  color: var(--text-secondary);
  line-height: 1.6;
  padding-left: 1.35rem;
}

/* ==========================================================================
   右侧浮动章节导航箭头 (Section Navigator)
   ========================================================================== */
.section-nav {
  position: fixed;
  right: 24px;
  bottom: 80px;
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 8px;
  background: rgba(18, 20, 26, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-pill);
  padding: 6px 4px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
}

.section-nav-btn {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.section-nav-btn:hover:not(:disabled) {
  background: var(--accent-bg);
  color: var(--accent-light);
}

.section-nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.section-nav-btn:focus-visible {
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

/* ==========================================================================
   知识科普文章与列表样式 (Articles & Blog)
   ========================================================================== */
.article-header {
  margin-bottom: 2rem;
}

.article-meta-bar {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-top: 0.75rem;
  flex-wrap: wrap;
}

.breadcrumb-nav {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.88rem;
  color: var(--text-muted);
  margin-bottom: 1.5rem;
}

.breadcrumb-nav a {
  color: var(--text-secondary);
}

.breadcrumb-nav a:hover {
  color: var(--accent-light);
}

.articles-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 1.5rem;
  margin-top: 1.5rem;
}

.article-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem 1.5rem;
  display: flex;
  flex-direction: column;
  transition: transform var(--transition-fast), border-color var(--transition-fast);
}

.article-card:hover {
  transform: translateY(-3px);
  border-color: var(--accent-border);
}

.article-card-tag {
  font-size: 0.78rem;
  font-weight: 700;
  color: var(--accent-light);
  margin-bottom: 0.6rem;
}

.article-card-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: #ffffff;
  margin-bottom: 0.75rem;
  line-height: 1.4;
}

.article-card-summary {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin-bottom: 1.25rem;
  flex: 1;
}

.article-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.82rem;
  color: var(--text-muted);
  padding-top: 0.75rem;
  border-top: 1px solid var(--border-subtle);
}

.article-body {
  font-size: 1rem;
  line-height: 1.85;
  color: var(--text-secondary);
}

.article-body h2 {
  font-size: 1.4rem;
  font-weight: 800;
  color: #ffffff;
  margin: 2.25rem 0 0.85rem;
  padding-bottom: 0.4rem;
  border-bottom: 1px solid var(--border-subtle);
}

.article-body h3 {
  font-size: 1.15rem;
  font-weight: 700;
  color: #e2e8f0;
  margin: 1.5rem 0 0.65rem;
}

.article-body p {
  margin-bottom: 1.25rem;
}

.article-body ul, .article-body ol {
  padding-left: 1.5rem;
  margin-bottom: 1.25rem;
}

.article-body li {
  margin-bottom: 0.45rem;
}

.article-cta-box {
  background: linear-gradient(145deg, rgba(26, 29, 38, 0.95), rgba(18, 20, 26, 0.95));
  border: 1px solid var(--accent-border);
  border-radius: var(--radius-lg);
  padding: 2rem;
  margin: 2.5rem 0;
  text-align: center;
}

.article-cta-box h3 {
  font-size: 1.35rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 0.75rem;
}

.article-cta-box p {
  font-size: 0.95rem;
  color: var(--text-secondary);
  max-width: 620px;
  margin: 0 auto 1.5rem;
}

/* ==========================================================================
   静态内容页通用样式 (About / Terms / Privacy / Sitemap)
   ========================================================================== */
.content-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2.5rem 2rem;
  margin-top: 1rem;
  line-height: 1.75;
}

.content-card h1 {
  font-family: var(--font-heading);
  font-size: 1.85rem;
  font-weight: 800;
  color: #ffffff;
  margin-bottom: 0.4rem;
}

.content-card .page-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 2rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border-subtle);
}

.content-card h2 {
  font-size: 1.25rem;
  font-weight: 700;
  color: #f1f5f9;
  margin: 1.75rem 0 0.65rem;
}

.content-card p {
  color: var(--text-secondary);
  margin-bottom: 1.15rem;
  font-size: 0.95rem;
}

.content-card ul {
  padding-left: 1.5rem;
  margin-bottom: 1.15rem;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.content-card li {
  margin-bottom: 0.45rem;
}

.sitemap-list {
  list-style: none;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}

.sitemap-item-link {
  display: block;
  padding: 1.25rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.sitemap-item-link:hover {
  background: rgba(245, 158, 11, 0.06);
  border-color: var(--accent-border);
  transform: translateY(-2px);
}

.sitemap-item-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: #ffffff;
  margin-bottom: 0.35rem;
}

.sitemap-item-url {
  font-size: 0.82rem;
  color: var(--accent-light);
  word-break: break-all;
}

/* ==========================================================================
   页面页脚 (Footer - 仅保留4个入口并在新标签页打开)
   ========================================================================== */
.site-footer {
  background: #07080a;
  border-top: 1px solid var(--border-subtle);
  padding: 3.5rem 1.5rem 2.25rem;
  color: var(--text-muted);
  font-size: 0.88rem;
}

.footer-container {
  max-width: 1160px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.footer-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-heading);
  font-size: 1.2rem;
  font-weight: 800;
  color: #ffffff;
}

.footer-nav {
  display: flex;
  align-items: center;
  gap: 1.75rem;
  list-style: none;
  flex-wrap: wrap;
}

.footer-nav a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  font-weight: 500;
  transition: color var(--transition-fast);
}

.footer-nav a:hover {
  color: var(--accent-light);
}

.footer-bottom {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.82rem;
  color: var(--text-dim);
}

/* ==========================================================================
   弹窗与遮罩层规范 (Modal & Backdrop)
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1.25rem;
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}

.modal-overlay.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}

.modal-container {
  position: relative;
  width: 100%;
  max-width: 440px;
  background: var(--modal-bg);
  border-radius: 16px;
  box-shadow: 0 20px 45px rgba(0, 0, 0, 0.45);
  border: 1px solid var(--modal-border);
  padding: 2.25rem 2rem 1.75rem;
  text-align: center;
  color: var(--modal-text-body);
  transform: scale(0.96);
  transition: transform 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-overlay.active .modal-container {
  transform: scale(1);
}

.modal-close-btn {
  position: absolute;
  top: 14px;
  right: 14px;
  width: 32px;
  height: 32px;
  background: transparent;
  border: none;
  font-size: 1.25rem;
  line-height: 1;
  color: #64748b;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: background var(--transition-fast), color var(--transition-fast);
}

.modal-close-btn:hover {
  background: #f1f5f9;
  color: #0f172a;
}

.modal-close-btn:focus-visible {
  outline: 2px solid var(--accent-dark);
  outline-offset: 2px;
}

.modal-header {
  margin-bottom: 1.25rem;
}

.modal-icon-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: #fef3c7;
  color: #d97706;
  font-size: 1.5rem;
  margin-bottom: 0.85rem;
}

.modal-title {
  font-size: 1.35rem;
  font-weight: 800;
  color: var(--modal-text-title);
  line-height: 1.3;
}

.modal-body {
  margin-bottom: 1.75rem;
}

.modal-text {
  font-size: 0.95rem;
  line-height: 1.7;
  color: var(--modal-text-body);
  text-align: left;
}

.modal-actions {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.modal-cta-btn {
  display: block;
  width: 100%;
  padding: 0.9rem 1.5rem;
  font-size: 1rem;
  font-weight: 700;
  color: #000000;
  background: var(--accent-color);
  border-radius: 999px;
  text-align: center;
  box-shadow: 0 4px 14px var(--accent-glow);
  transition: transform var(--transition-fast), background var(--transition-fast), box-shadow var(--transition-fast);
  cursor: pointer;
  border: none;
}

.modal-cta-btn:hover {
  background: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 6px 18px rgba(245, 158, 11, 0.4);
}

.modal-cta-btn:focus-visible {
  outline: 2px solid #000000;
  outline-offset: 2px;
}

.modal-sub-dismiss {
  font-size: 0.88rem;
  font-weight: 500;
  color: #64748b;
  cursor: pointer;
  background: none;
  border: none;
  padding: 0.5rem;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast);
}

.modal-sub-dismiss:hover {
  color: #1e293b;
  text-decoration: underline;
}

.modal-sub-dismiss:focus-visible {
  outline: 2px solid var(--accent-dark);
  outline-offset: 1px;
}

/* ==========================================================================
   响应式断点适配 (Responsive Design)
   ========================================================================== */
@media (max-width: 960px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .features-grid, .pricing-grid {
    grid-template-columns: 1fr;
    gap: 1.25rem;
  }
  .faq-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .site-nav .nav-links {
    display: none;
  }

  .main-wrapper {
    padding: 1.5rem 1.15rem 3.5rem;
  }

  .hero-section {
    padding: 2rem 0;
  }

  .hero-actions {
    flex-direction: column;
    width: 100%;
  }

  .btn-primary, .btn-secondary {
    width: 100%;
    text-align: center;
  }

  .footer-top {
    flex-direction: column;
    align-items: flex-start;
  }

  .modal-container {
    padding: 1.85rem 1.35rem 1.5rem;
    max-width: 92%;
  }

  .section-nav {
    right: 12px;
    bottom: 24px;
    transform: scale(0.9);
  }
}