/* ==========================================
   xxyun 机场 - 主样式表
   深空暗色主题 + 玻璃态 + 微动效
   ========================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&family=Noto+Sans+SC:wght@300;400;500;700;900&display=swap');

:root {
  --bg-primary: #070b18;
  --bg-secondary: #0d1428;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-card-hover: rgba(255, 255, 255, 0.08);
  --border: rgba(255, 255, 255, 0.08);
  --border-glow: rgba(99, 102, 241, 0.3);

  --brand-purple: #6366f1;
  --brand-blue: #3b82f6;
  --brand-cyan: #06b6d4;
  --brand-gradient: linear-gradient(135deg, #6366f1 0%, #3b82f6 50%, #06b6d4 100%);
  --brand-gradient-text: linear-gradient(135deg, #818cf8, #60a5fa, #22d3ee);

  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;

  --shadow-glow: 0 0 40px rgba(99, 102, 241, 0.15);
  --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4);

  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Reset & Base */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: 'Noto Sans SC', 'Inter', -apple-system, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}
a { color: var(--brand-purple); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--brand-cyan); }
img { max-width: 100%; display: block; }

/* Scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-secondary); }
::-webkit-scrollbar-thumb { background: var(--brand-purple); border-radius: 3px; }

/* ==========================================
   背景粒子 & 网格
   ========================================== */
.bg-grid {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  background-image:
    linear-gradient(rgba(99,102,241,0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(99,102,241,0.03) 1px, transparent 1px);
  background-size: 50px 50px;
}
.bg-orb {
  position: fixed; border-radius: 50%; filter: blur(80px); pointer-events: none; z-index: 0;
}
.bg-orb-1 {
  width: 600px; height: 600px;
  background: radial-gradient(circle, rgba(99,102,241,0.12) 0%, transparent 70%);
  top: -200px; left: -200px;
}
.bg-orb-2 {
  width: 500px; height: 500px;
  background: radial-gradient(circle, rgba(6,182,212,0.08) 0%, transparent 70%);
  bottom: -100px; right: -100px;
}

/* ==========================================
   导航栏
   ========================================== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  padding: 0 24px;
  height: 64px;
  display: flex; align-items: center;
  background: rgba(7, 11, 24, 0.8);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
  transition: all var(--transition);
}
.navbar.scrolled {
  background: rgba(7, 11, 24, 0.95);
  box-shadow: 0 4px 24px rgba(0,0,0,0.5);
}
.nav-container { max-width: 1200px; width: 100%; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; }
.nav-logo {
  display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 1.4rem;
}
.nav-logo .logo-icon {
  width: 36px; height: 36px; border-radius: 8px;
  background: var(--brand-gradient);
  display: flex; align-items: center; justify-content: center;
  font-size: 1rem; font-weight: 900; color: #fff;
  box-shadow: 0 0 16px rgba(99,102,241,0.4);
}
.nav-logo .logo-text {
  background: var(--brand-gradient-text); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.nav-menu { display: flex; align-items: center; gap: 8px; list-style: none; }
.nav-menu a {
  padding: 6px 14px; border-radius: var(--radius-sm);
  color: var(--text-secondary); font-size: 0.9rem; font-weight: 500;
  transition: all var(--transition);
}
.nav-menu a:hover { color: var(--text-primary); background: var(--bg-card); }
.nav-cta {
  padding: 8px 20px !important;
  background: var(--brand-gradient) !important;
  color: #fff !important;
  border-radius: var(--radius-sm) !important;
  font-weight: 600 !important;
  box-shadow: 0 0 20px rgba(99,102,241,0.3);
}
.nav-cta:hover { box-shadow: 0 0 30px rgba(99,102,241,0.5) !important; transform: translateY(-1px); }
.nav-toggle { display: none; background: none; border: none; color: var(--text-primary); cursor: pointer; font-size: 1.4rem; }

/* ==========================================
   Hero 区块
   ========================================== */
.hero {
  position: relative; z-index: 1;
  min-height: 100vh;
  display: flex; align-items: center; justify-content: center;
  padding: 120px 24px 80px;
  text-align: center;
}
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 16px; border-radius: 100px;
  background: rgba(99,102,241,0.1); border: 1px solid rgba(99,102,241,0.3);
  font-size: 0.82rem; color: var(--brand-purple); font-weight: 600;
  margin-bottom: 28px;
  animation: fadeInUp 0.6s ease both;
}
.hero-badge::before { content: ''; width: 8px; height: 8px; border-radius: 50%; background: var(--brand-purple); animation: pulse-dot 2s infinite; }
.hero-title {
  font-size: clamp(2.4rem, 6vw, 4.2rem);
  font-weight: 900; line-height: 1.15;
  margin-bottom: 24px;
  animation: fadeInUp 0.6s 0.1s ease both;
}
.hero-title .highlight {
  background: var(--brand-gradient-text); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.hero-desc {
  font-size: 1.15rem; color: var(--text-secondary); max-width: 640px; margin: 0 auto 40px;
  animation: fadeInUp 0.6s 0.2s ease both;
}
.hero-actions {
  display: flex; gap: 16px; justify-content: center; flex-wrap: wrap;
  animation: fadeInUp 0.6s 0.3s ease both;
}
.btn-primary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px; border-radius: var(--radius-md);
  background: var(--brand-gradient); color: #fff;
  font-weight: 700; font-size: 1rem;
  box-shadow: 0 0 30px rgba(99,102,241,0.35);
  transition: all var(--transition); border: none; cursor: pointer;
}
.btn-primary:hover { color: #fff; transform: translateY(-2px); box-shadow: 0 0 50px rgba(99,102,241,0.5); }
.btn-secondary {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 14px 32px; border-radius: var(--radius-md);
  background: var(--bg-card); color: var(--text-primary);
  font-weight: 600; font-size: 1rem;
  border: 1px solid var(--border);
  transition: all var(--transition); cursor: pointer;
}
.btn-secondary:hover { color: var(--text-primary); background: var(--bg-card-hover); border-color: var(--border-glow); }

.hero-stats {
  display: flex; justify-content: center; gap: 48px; margin-top: 60px; flex-wrap: wrap;
  animation: fadeInUp 0.6s 0.4s ease both;
}
.stat-item { text-align: center; }
.stat-num {
  font-size: 2.2rem; font-weight: 900;
  background: var(--brand-gradient-text); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text;
}
.stat-label { font-size: 0.85rem; color: var(--text-muted); margin-top: 4px; }

/* 信任徽章 */
.trust-bar {
  position: relative; z-index: 1;
  padding: 24px;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  background: rgba(255,255,255,0.02);
}
.trust-bar-inner {
  max-width: 1200px; margin: 0 auto;
  display: flex; align-items: center; justify-content: center; gap: 40px; flex-wrap: wrap;
}
.trust-item {
  display: flex; align-items: center; gap: 10px;
  font-size: 0.9rem; color: var(--text-secondary);
}
.trust-item .icon { font-size: 1.2rem; }

/* ==========================================
   通用 Section
   ========================================== */
.section { position: relative; z-index: 1; padding: 100px 24px; }
.section-sm { padding: 60px 24px; }
.container { max-width: 1200px; margin: 0 auto; }
.section-label {
  display: inline-block;
  font-size: 0.78rem; font-weight: 700; letter-spacing: 2px; text-transform: uppercase;
  color: var(--brand-purple); margin-bottom: 16px;
}
.section-title {
  font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 800; line-height: 1.2;
  margin-bottom: 16px;
}
.section-desc { font-size: 1.05rem; color: var(--text-secondary); max-width: 560px; }
.section-header-center { text-align: center; }
.section-header-center .section-desc { margin: 0 auto; }

/* ==========================================
   特性卡片
   ========================================== */
.features-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); gap: 24px; margin-top: 60px; }
.feature-card {
  padding: 32px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  backdrop-filter: blur(10px);
  transition: all var(--transition);
  position: relative; overflow: hidden;
}
.feature-card::before {
  content: ''; position: absolute; inset: 0;
  background: var(--brand-gradient); opacity: 0;
  transition: opacity var(--transition);
}
.feature-card:hover { border-color: var(--border-glow); transform: translateY(-4px); box-shadow: var(--shadow-glow); }
.feature-card:hover::before { opacity: 0.04; }
.feature-icon {
  width: 52px; height: 52px; border-radius: var(--radius-sm);
  background: rgba(99,102,241,0.15); border: 1px solid rgba(99,102,241,0.2);
  display: flex; align-items: center; justify-content: center;
  font-size: 1.5rem; margin-bottom: 20px;
}
.feature-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 10px; }
.feature-card p { font-size: 0.93rem; color: var(--text-secondary); line-height: 1.6; }
.feature-tag {
  display: inline-block; margin-top: 16px;
  padding: 4px 10px; border-radius: 100px;
  background: rgba(16,185,129,0.1); border: 1px solid rgba(16,185,129,0.2);
  font-size: 0.75rem; color: var(--success); font-weight: 600;
}

/* ==========================================
   套餐价格
   ========================================== */
.plans-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 24px; margin-top: 60px; }
.plan-card {
  padding: 36px 28px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  backdrop-filter: blur(10px);
  transition: all var(--transition);
  position: relative;
}
.plan-card.popular {
  border-color: var(--brand-purple);
  background: rgba(99,102,241,0.06);
  box-shadow: var(--shadow-glow);
}
.plan-badge {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  padding: 5px 18px; border-radius: 100px;
  background: var(--brand-gradient); color: #fff;
  font-size: 0.78rem; font-weight: 700; white-space: nowrap;
}
.plan-name { font-size: 1.1rem; font-weight: 700; color: var(--text-secondary); margin-bottom: 20px; }
.plan-price { margin-bottom: 8px; }
.plan-price .amount { font-size: 3rem; font-weight: 900; color: var(--text-primary); }
.plan-price .currency { font-size: 1.2rem; font-weight: 600; color: var(--text-secondary); vertical-align: super; }
.plan-price .period { font-size: 0.9rem; color: var(--text-muted); }
.plan-desc { font-size: 0.88rem; color: var(--text-muted); margin-bottom: 28px; }
.plan-features { list-style: none; margin-bottom: 32px; display: flex; flex-direction: column; gap: 12px; }
.plan-features li { display: flex; align-items: center; gap: 10px; font-size: 0.92rem; }
.plan-features li::before { content: '✓'; width: 20px; height: 20px; border-radius: 50%; background: rgba(16,185,129,0.15); color: var(--success); display: flex; align-items: center; justify-content: center; font-size: 0.7rem; font-weight: 700; flex-shrink: 0; }
.plan-features li.disabled { color: var(--text-muted); }
.plan-features li.disabled::before { content: '×'; background: rgba(100,116,139,0.1); color: var(--text-muted); }
.plan-btn {
  width: 100%; padding: 13px;
  border-radius: var(--radius-md); border: none; cursor: pointer;
  font-weight: 700; font-size: 1rem; transition: all var(--transition);
}
.plan-btn-outline {
  background: transparent; color: var(--brand-purple);
  border: 1.5px solid var(--brand-purple);
}
.plan-btn-outline:hover { background: rgba(99,102,241,0.1); }
.plan-btn-filled {
  background: var(--brand-gradient); color: #fff;
  box-shadow: 0 0 20px rgba(99,102,241,0.3);
}
.plan-btn-filled:hover { box-shadow: 0 0 35px rgba(99,102,241,0.5); transform: translateY(-1px); }

/* ==========================================
   节点地图 & 覆盖
   ========================================== */
.nodes-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(180px, 1fr)); gap: 16px; margin-top: 48px; }
.node-card {
  padding: 20px 16px; border-radius: var(--radius-md);
  background: var(--bg-card); border: 1px solid var(--border);
  display: flex; flex-direction: column; align-items: center; gap: 10px;
  transition: all var(--transition); text-align: center;
}
.node-card:hover { border-color: var(--border-glow); background: var(--bg-card-hover); }
.node-flag { font-size: 2rem; }
.node-name { font-size: 0.9rem; font-weight: 600; }
.node-speed { font-size: 0.8rem; color: var(--success); display: flex; align-items: center; gap: 4px; }
.node-speed::before { content: ''; width: 6px; height: 6px; border-radius: 50%; background: var(--success); animation: pulse-dot 2s infinite; }

/* ==========================================
   FAQ
   ========================================== */
.faq-list { margin-top: 60px; display: flex; flex-direction: column; gap: 16px; max-width: 860px; margin-left: auto; margin-right: auto; }
.faq-item {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-md); overflow: hidden;
  transition: border-color var(--transition);
}
.faq-item.active { border-color: var(--border-glow); }
.faq-question {
  width: 100%; padding: 22px 24px; background: none; border: none; cursor: pointer;
  display: flex; align-items: center; justify-content: space-between; gap: 16px;
  text-align: left; color: var(--text-primary); font-size: 1rem; font-weight: 600;
  transition: color var(--transition);
}
.faq-question:hover { color: var(--brand-purple); }
.faq-icon {
  width: 28px; height: 28px; border-radius: 50%;
  background: rgba(99,102,241,0.1); border: 1px solid rgba(99,102,241,0.2);
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0; font-size: 1.2rem; color: var(--brand-purple);
  transition: transform var(--transition);
}
.faq-item.active .faq-icon { transform: rotate(45deg); }
.faq-answer {
  max-height: 0; overflow: hidden; transition: max-height 0.4s ease, padding 0.3s ease;
  padding: 0 24px;
}
.faq-answer-inner { padding-bottom: 22px; color: var(--text-secondary); font-size: 0.95rem; line-height: 1.8; }
.faq-item.active .faq-answer { max-height: 500px; }

/* ==========================================
   文章/博客
   ========================================== */
.articles-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr)); gap: 28px; margin-top: 56px; }
.article-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); overflow: hidden;
  transition: all var(--transition); display: flex; flex-direction: column;
}
.article-card:hover { border-color: var(--border-glow); transform: translateY(-4px); box-shadow: var(--shadow-card); }
.article-cover {
  height: 200px; background: var(--brand-gradient); position: relative; overflow: hidden;
  display: flex; align-items: center; justify-content: center; font-size: 3rem;
}
.article-cover-2 { background: linear-gradient(135deg, #1e3a5f 0%, #0d2137 100%); }
.article-cover-3 { background: linear-gradient(135deg, #1a1f3a 0%, #2d1b5a 100%); }
.article-cover-4 { background: linear-gradient(135deg, #0f2a1e 0%, #1a3a2f 100%); }
.article-cover-5 { background: linear-gradient(135deg, #2a1a0f 0%, #3a2a1a 100%); }
.article-cover-6 { background: linear-gradient(135deg, #2a0f1a 0%, #1a0a0f 100%); }
.article-body { padding: 24px; flex: 1; display: flex; flex-direction: column; }
.article-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 14px; }
.article-tag {
  padding: 3px 10px; border-radius: 100px; font-size: 0.75rem; font-weight: 600;
  background: rgba(99,102,241,0.1); color: var(--brand-purple); border: 1px solid rgba(99,102,241,0.2);
}
.article-title { font-size: 1.05rem; font-weight: 700; margin-bottom: 10px; line-height: 1.4; }
.article-excerpt { font-size: 0.88rem; color: var(--text-secondary); line-height: 1.7; flex: 1; margin-bottom: 20px; }
.article-meta { display: flex; align-items: center; justify-content: space-between; }
.article-date { font-size: 0.8rem; color: var(--text-muted); }
.article-read-more {
  font-size: 0.85rem; font-weight: 600; color: var(--brand-purple);
  display: flex; align-items: center; gap: 4px;
}
.article-read-more:hover { color: var(--brand-cyan); }

/* ==========================================
   CTA Banner
   ========================================== */
.cta-section {
  position: relative; z-index: 1; padding: 100px 24px;
}
.cta-box {
  max-width: 800px; margin: 0 auto;
  padding: 64px 48px; border-radius: var(--radius-xl);
  background: linear-gradient(135deg, rgba(99,102,241,0.15), rgba(6,182,212,0.08));
  border: 1px solid rgba(99,102,241,0.25);
  text-align: center; position: relative; overflow: hidden;
}
.cta-box::before {
  content: ''; position: absolute;
  top: -60px; right: -60px; width: 250px; height: 250px;
  background: radial-gradient(circle, rgba(99,102,241,0.2) 0%, transparent 70%);
  border-radius: 50%;
}
.cta-box h2 { font-size: clamp(1.6rem, 4vw, 2.4rem); font-weight: 800; margin-bottom: 16px; }
.cta-box p { font-size: 1.05rem; color: var(--text-secondary); margin-bottom: 36px; }

/* ==========================================
   Footer
   ========================================== */
.footer {
  position: relative; z-index: 1;
  padding: 60px 24px 32px;
  border-top: 1px solid var(--border);
}
.footer-grid {
  max-width: 1200px; margin: 0 auto;
  display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 48px;
  margin-bottom: 48px;
}
.footer-brand p { font-size: 0.9rem; color: var(--text-secondary); margin-top: 12px; max-width: 280px; line-height: 1.7; }
.footer-col h4 { font-size: 0.88rem; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; color: var(--text-muted); margin-bottom: 20px; }
.footer-col ul { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-col a { font-size: 0.9rem; color: var(--text-secondary); transition: color var(--transition); }
.footer-col a:hover { color: var(--brand-purple); }
.footer-bottom {
  max-width: 1200px; margin: 0 auto;
  padding-top: 32px; border-top: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between; flex-wrap: gap;
  font-size: 0.85rem; color: var(--text-muted);
}
.footer-disclaimer { font-size: 0.78rem; color: var(--text-muted); margin-top: 8px; }

/* ==========================================
   文章详情页
   ========================================== */
.article-hero {
  position: relative; z-index: 1;
  padding: 140px 24px 80px;
  text-align: center;
}
.article-hero .article-tags { justify-content: center; margin-bottom: 24px; }
.article-hero h1 { font-size: clamp(1.8rem, 4vw, 2.8rem); font-weight: 900; line-height: 1.25; margin-bottom: 20px; }
.article-hero .meta { font-size: 0.88rem; color: var(--text-muted); display: flex; align-items: center; justify-content: center; gap: 16px; flex-wrap: wrap; }
.article-hero .meta span { display: flex; align-items: center; gap: 6px; }

.article-content-wrap { max-width: 780px; margin: 0 auto; padding: 0 24px 100px; position: relative; z-index: 1; }
.article-content { font-size: 1.02rem; line-height: 1.9; color: var(--text-secondary); }
.article-content h2 { font-size: 1.55rem; font-weight: 800; color: var(--text-primary); margin: 52px 0 20px; padding-bottom: 12px; border-bottom: 1px solid var(--border); }
.article-content h3 { font-size: 1.2rem; font-weight: 700; color: var(--text-primary); margin: 36px 0 14px; }
.article-content p { margin-bottom: 20px; }
.article-content ul, .article-content ol { padding-left: 24px; margin-bottom: 20px; display: flex; flex-direction: column; gap: 8px; }
.article-content li { line-height: 1.7; }
.article-content strong { color: var(--text-primary); font-weight: 700; }
.article-content .highlight-box {
  padding: 20px 24px; border-radius: var(--radius-md);
  background: rgba(99,102,241,0.08); border-left: 3px solid var(--brand-purple);
  margin: 28px 0;
}
.article-content .highlight-box p { margin: 0; }
.article-content table { width: 100%; border-collapse: collapse; margin: 28px 0; font-size: 0.93rem; }
.article-content th { padding: 12px 16px; background: rgba(99,102,241,0.1); text-align: left; font-weight: 700; color: var(--text-primary); border: 1px solid var(--border); }
.article-content td { padding: 12px 16px; border: 1px solid var(--border); color: var(--text-secondary); }
.article-content td strong { color: var(--success); }
.article-cta {
  margin-top: 60px; padding: 40px;
  background: linear-gradient(135deg, rgba(99,102,241,0.12), rgba(6,182,212,0.06));
  border: 1px solid rgba(99,102,241,0.2); border-radius: var(--radius-lg);
  text-align: center;
}
.article-cta h3 { font-size: 1.4rem; font-weight: 800; margin-bottom: 12px; }
.article-cta p { color: var(--text-secondary); margin-bottom: 24px; }

/* ==========================================
   动画
   ========================================== */
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}
@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}
.fade-in { opacity: 0; transform: translateY(30px); transition: opacity 0.7s ease, transform 0.7s ease; }
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* ==========================================
   响应式
   ========================================== */
@media (max-width: 1024px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-menu { display: none; flex-direction: column; position: fixed; top: 64px; left: 0; right: 0; background: var(--bg-secondary); padding: 20px; border-bottom: 1px solid var(--border); }
  .nav-menu.open { display: flex; }
  .nav-toggle { display: block; }
  .hero-stats { gap: 32px; }
  .footer-grid { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; gap: 8px; text-align: center; }
  .cta-box { padding: 40px 24px; }
  .plans-grid { grid-template-columns: 1fr; max-width: 420px; margin-left: auto; margin-right: auto; }
  .articles-grid { grid-template-columns: 1fr; }
  .faq-list { margin-top: 40px; }
}
@media (max-width: 480px) {
  .hero-actions { flex-direction: column; align-items: center; }
  .btn-primary, .btn-secondary { width: 100%; justify-content: center; }
}