/* roulang page: index */
/* ===== CSS Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; font-size: 16px; line-height: 1.7; color: #1F2937; background-color: #F9FAFB; -webkit-font-smoothing: antialiased; }
a { color: #2563EB; text-decoration: none; transition: color 0.2s; }
a:hover { color: #1D4ED8; }
img { max-width: 100%; height: auto; display: block; }
ul, ol { list-style: none; }
button, input, textarea { font-family: inherit; font-size: inherit; border: none; outline: none; }
button { cursor: pointer; }
/* ===== Design Variables ===== */
:root {
  --primary: #2563EB;
  --primary-dark: #1D4ED8;
  --primary-light: #3B82F6;
  --secondary: #F59E0B;
  --secondary-dark: #D97706;
  --secondary-light: #FBBF24;
  --bg-body: #F9FAFB;
  --bg-card: #FFFFFF;
  --bg-dark: #1F2937;
  --bg-dark-light: #374151;
  --text-primary: #1F2937;
  --text-secondary: #6B7280;
  --text-dark: #111827;
  --text-light: #F9FAFB;
  --border: #E5E7EB;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08), 0 1px 2px rgba(0,0,0,0.06);
  --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
  --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --max-width: 1200px;
  --header-height: 72px;
}
/* ===== Container ===== */
.container { width: 100%; max-width: var(--max-width); margin: 0 auto; padding-left: 20px; padding-right: 20px; }
@media (max-width: 768px) { .container { padding-left: 16px; padding-right: 16px; } }
/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 { color: var(--text-dark); font-weight: 700; line-height: 1.25; }
h1 { font-size: 42px; }
h2 { font-size: 32px; margin-bottom: 16px; }
h3 { font-size: 22px; font-weight: 600; margin-bottom: 12px; }
h4 { font-size: 18px; font-weight: 600; margin-bottom: 8px; }
p { margin-bottom: 16px; color: var(--text-primary); }
.text-small { font-size: 14px; color: var(--text-secondary); }
.text-muted { color: var(--text-secondary); }
@media (max-width: 768px) {
  h1 { font-size: 32px; }
  h2 { font-size: 24px; }
  h3 { font-size: 20px; }
  h4 { font-size: 17px; }
  body { font-size: 15px; }
}
/* ===== Buttons ===== */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 12px 28px; border-radius: var(--radius-sm); font-weight: 600; font-size: 16px; line-height: 1.4; transition: var(--transition); border: 2px solid transparent; text-align: center; white-space: nowrap; }
.btn-primary { background: var(--primary); color: #fff; border-color: var(--primary); }
.btn-primary:hover { background: var(--primary-dark); border-color: var(--primary-dark); color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-secondary { background: var(--secondary); color: #fff; border-color: var(--secondary); }
.btn-secondary:hover { background: var(--secondary-dark); border-color: var(--secondary-dark); color: #fff; transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; color: var(--primary); border-color: var(--primary); }
.btn-outline:hover { background: var(--primary); color: #fff; transform: translateY(-1px); }
.btn-ghost { background: transparent; color: var(--text-light); border-color: rgba(255,255,255,0.5); }
.btn-ghost:hover { background: rgba(255,255,255,0.15); color: #fff; border-color: #fff; }
.btn-lg { padding: 16px 36px; font-size: 18px; }
.btn-sm { padding: 8px 18px; font-size: 14px; }
.btn-block { width: 100%; }
.btn .fa-arrow-right { transition: transform 0.2s; }
.btn:hover .fa-arrow-right { transform: translateX(4px); }
@media (max-width: 768px) { .btn { padding: 10px 22px; font-size: 15px; } .btn-lg { padding: 14px 28px; font-size: 16px; } }
/* ===== Badge ===== */
.badge { display: inline-block; padding: 4px 12px; border-radius: 20px; font-size: 12px; font-weight: 600; letter-spacing: 0.3px; }
.badge-primary { background: var(--primary); color: #fff; }
.badge-secondary { background: var(--secondary); color: #fff; }
.badge-light { background: #EFF6FF; color: var(--primary); }
.badge-hot { background: #FEE2E2; color: #DC2626; }
/* ===== Card ===== */
.card { background: var(--bg-card); border-radius: var(--radius-lg); box-shadow: var(--shadow-md); transition: var(--transition); overflow: hidden; }
.card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); }
.card-body { padding: 28px; }
.card-img { width: 100%; height: 200px; object-fit: cover; border-radius: var(--radius-lg) var(--radius-lg) 0 0; }
.card-title { font-size: 20px; font-weight: 600; margin-bottom: 8px; color: var(--text-dark); }
.card-text { font-size: 15px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 16px; }
.card-link { font-weight: 600; font-size: 15px; color: var(--primary); display: inline-flex; align-items: center; gap: 6px; transition: var(--transition); }
.card-link:hover { color: var(--primary-dark); gap: 10px; }
/* ===== Section Spacing ===== */
.section { padding: 100px 0; }
.section-sm { padding: 60px 0; }
.section-lg { padding: 120px 0; }
.section-title { text-align: center; margin-bottom: 48px; }
.section-title h2 { margin-bottom: 12px; }
.section-title p { max-width: 640px; margin: 0 auto; color: var(--text-secondary); font-size: 17px; }
@media (max-width: 768px) { .section { padding: 60px 0; } .section-title { margin-bottom: 32px; } }
/* ===== Grid System ===== */
.grid { display: grid; gap: 28px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 1024px) { .grid-4 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 768px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }
/* ===== Header / Navigation ===== */
.header { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; height: var(--header-height); background: rgba(255,255,255,0.95); backdrop-filter: blur(12px); border-bottom: 1px solid rgba(229,231,235,0.6); transition: var(--transition); }
.header.scrolled { box-shadow: var(--shadow-md); background: rgba(255,255,255,0.98); }
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 100%; max-width: var(--max-width); margin: 0 auto; padding: 0 20px; }
.header-logo { display: flex; align-items: center; gap: 10px; font-size: 22px; font-weight: 700; color: var(--text-dark); }
.header-logo img { height: 36px; width: auto; }
.header-logo .logo-icon { width: 36px; height: 36px; background: linear-gradient(135deg, var(--primary), var(--secondary)); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; color: #fff; font-size: 18px; font-weight: 700; }
.header-logo .logo-text { background: linear-gradient(135deg, var(--primary), var(--secondary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.header-nav { display: flex; align-items: center; gap: 32px; }
.header-nav a { font-size: 16px; font-weight: 500; color: var(--text-primary); position: relative; padding: 4px 0; transition: var(--transition); }
.header-nav a::after { content: ''; position: absolute; bottom: -2px; left: 0; width: 0; height: 2px; background: var(--primary); transition: var(--transition); border-radius: 1px; }
.header-nav a:hover { color: var(--primary); }
.header-nav a:hover::after { width: 100%; }
.header-nav a.active { color: var(--primary); }
.header-nav a.active::after { width: 100%; }
.header-cta { display: flex; align-items: center; gap: 12px; }
.hamburger { display: none; flex-direction: column; gap: 5px; cursor: pointer; padding: 4px; background: none; border: none; }
.hamburger span { width: 26px; height: 3px; background: var(--text-dark); border-radius: 2px; transition: var(--transition); }
.hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 6px); }
.hamburger.active span:nth-child(2) { opacity: 0; }
.hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -6px); }
@media (max-width: 900px) {
  .header-nav { position: fixed; top: var(--header-height); left: 0; right: 0; background: rgba(255,255,255,0.98); backdrop-filter: blur(12px); flex-direction: column; padding: 24px 20px; gap: 16px; box-shadow: var(--shadow-lg); transform: translateY(-120%); opacity: 0; transition: var(--transition); border-bottom: 1px solid var(--border); }
  .header-nav.open { transform: translateY(0); opacity: 1; }
  .header-nav a { font-size: 18px; padding: 8px 0; width: 100%; text-align: center; }
  .hamburger { display: flex; }
  .header-cta .btn { padding: 8px 16px; font-size: 14px; }
}
/* ===== Hero ===== */
.hero { position: relative; min-height: 680px; display: flex; align-items: center; margin-top: var(--header-height); background: linear-gradient(135deg, rgba(37,99,235,0.92), rgba(245,158,11,0.85)), url('/assets/images/backpic/back-1.png') center/cover no-repeat; overflow: hidden; }
.hero::before { content: ''; position: absolute; inset: 0; background: radial-gradient(ellipse at 30% 50%, rgba(255,255,255,0.12) 0%, transparent 70%); pointer-events: none; }
.hero .container { position: relative; z-index: 2; }
.hero-content { max-width: 720px; }
.hero-badge { display: inline-block; padding: 6px 16px; background: rgba(255,255,255,0.18); backdrop-filter: blur(4px); border-radius: 20px; color: #fff; font-size: 14px; font-weight: 500; margin-bottom: 20px; border: 1px solid rgba(255,255,255,0.25); }
.hero-title { font-size: 48px; font-weight: 800; color: #fff; line-height: 1.15; margin-bottom: 16px; text-shadow: 0 2px 20px rgba(0,0,0,0.15); }
.hero-title span { background: linear-gradient(135deg, #FDE68A, #FBBF24); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-subtitle { font-size: 20px; color: rgba(255,255,255,0.9); line-height: 1.6; margin-bottom: 32px; max-width: 580px; font-weight: 400; }
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
.hero-stats { display: flex; gap: 40px; margin-top: 48px; padding-top: 32px; border-top: 1px solid rgba(255,255,255,0.2); }
.hero-stat-item { text-align: left; }
.hero-stat-number { font-size: 32px; font-weight: 800; color: #fff; line-height: 1.2; }
.hero-stat-number .fa { font-size: 22px; margin-right: 4px; color: #FDE68A; }
.hero-stat-label { font-size: 14px; color: rgba(255,255,255,0.75); margin-top: 2px; }
.hero-decor { position: absolute; right: -40px; top: 10%; width: 400px; height: 400px; border-radius: 50%; background: rgba(255,255,255,0.06); pointer-events: none; }
.hero-decor-2 { position: absolute; left: -80px; bottom: -80px; width: 300px; height: 300px; border-radius: 50%; background: rgba(255,255,255,0.04); pointer-events: none; }
@media (max-width: 768px) {
  .hero { min-height: 520px; }
  .hero-title { font-size: 32px; }
  .hero-subtitle { font-size: 17px; }
  .hero-stats { gap: 24px; flex-wrap: wrap; }
  .hero-stat-number { font-size: 26px; }
  .hero-decor, .hero-decor-2 { display: none; }
}
/* ===== Features / Core Modules ===== */
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.feature-card { background: var(--bg-card); border-radius: var(--radius-lg); padding: 36px 28px; box-shadow: var(--shadow-md); transition: var(--transition); position: relative; border: 1px solid var(--border); }
.feature-card:hover { box-shadow: var(--shadow-xl); transform: translateY(-6px); border-color: var(--primary-light); }
.feature-card .badge { position: absolute; top: 16px; right: 16px; }
.feature-icon { width: 56px; height: 56px; background: linear-gradient(135deg, #EFF6FF, #DBEAFE); border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; font-size: 24px; color: var(--primary); margin-bottom: 20px; transition: var(--transition); }
.feature-card:hover .feature-icon { background: linear-gradient(135deg, var(--primary), var(--primary-light)); color: #fff; }
.feature-card h3 { font-size: 20px; margin-bottom: 10px; }
.feature-card p { font-size: 15px; color: var(--text-secondary); line-height: 1.6; margin-bottom: 16px; }
.feature-card .card-link { font-size: 15px; }
@media (max-width: 1024px) { .features-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 768px) { .features-grid { grid-template-columns: 1fr; } .feature-card { padding: 24px 20px; } }
/* ===== Scenarios ===== */
.scenario-grid { display: grid; gap: 40px; }
.scenario-item { display: flex; align-items: center; gap: 48px; background: var(--bg-card); border-radius: var(--radius-lg); padding: 32px; box-shadow: var(--shadow-sm); border: 1px solid var(--border); transition: var(--transition); }
.scenario-item:hover { box-shadow: var(--shadow-md); }
.scenario-item.reverse { flex-direction: row-reverse; }
.scenario-img { flex: 0 0 320px; border-radius: var(--radius-md); overflow: hidden; }
.scenario-img img { width: 100%; height: 220px; object-fit: cover; border-radius: var(--radius-md); transition: var(--transition); }
.scenario-item:hover .scenario-img img { transform: scale(1.03); }
.scenario-text { flex: 1; }
.scenario-text h3 { font-size: 22px; margin-bottom: 10px; }
.scenario-text p { font-size: 16px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 16px; }
.scenario-tags { display: flex; gap: 8px; flex-wrap: wrap; margin-bottom: 16px; }
.scenario-tags span { padding: 4px 12px; background: #EFF6FF; color: var(--primary); border-radius: 20px; font-size: 13px; font-weight: 500; }
@media (max-width: 900px) {
  .scenario-item, .scenario-item.reverse { flex-direction: column; gap: 24px; padding: 24px; }
  .scenario-img { flex: none; width: 100%; }
  .scenario-img img { height: 180px; }
}
/* ===== Stats / Achievements ===== */
.stats-section { background: linear-gradient(135deg, #1E3A5F, #1F2937); color: #fff; }
.stats-section .section-title h2 { color: #fff; }
.stats-section .section-title p { color: rgba(255,255,255,0.7); }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; text-align: center; }
.stat-card { padding: 32px 20px; background: rgba(255,255,255,0.08); border-radius: var(--radius-lg); backdrop-filter: blur(4px); border: 1px solid rgba(255,255,255,0.1); transition: var(--transition); }
.stat-card:hover { background: rgba(255,255,255,0.14); transform: translateY(-3px); }
.stat-card .stat-icon { font-size: 36px; margin-bottom: 12px; color: var(--secondary-light); }
.stat-card .stat-number { font-size: 40px; font-weight: 800; color: #fff; line-height: 1.2; }
.stat-card .stat-label { font-size: 15px; color: rgba(255,255,255,0.7); margin-top: 6px; }
.client-logos { display: flex; justify-content: center; gap: 40px; flex-wrap: wrap; margin-top: 48px; padding-top: 40px; border-top: 1px solid rgba(255,255,255,0.1); }
.client-logo-item { font-size: 20px; color: rgba(255,255,255,0.5); font-weight: 600; letter-spacing: 1px; transition: var(--transition); padding: 8px 20px; background: rgba(255,255,255,0.05); border-radius: var(--radius-sm); }
.client-logo-item:hover { color: rgba(255,255,255,0.9); background: rgba(255,255,255,0.1); }
@media (max-width: 768px) { .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; } .stat-card .stat-number { font-size: 30px; } }
/* ===== News / CMS List ===== */
.news-list-area { background: var(--bg-body); }
.news-card { display: flex; gap: 24px; background: var(--bg-card); border-radius: var(--radius-lg); padding: 24px; box-shadow: var(--shadow-sm); border: 1px solid var(--border); transition: var(--transition); align-items: flex-start; }
.news-card:hover { box-shadow: var(--shadow-md); transform: translateX(4px); }
.news-card-img { flex: 0 0 140px; height: 100px; border-radius: var(--radius-sm); overflow: hidden; }
.news-card-img img { width: 100%; height: 100%; object-fit: cover; }
.news-card-body { flex: 1; min-width: 0; }
.news-card-body h3 { font-size: 17px; font-weight: 600; margin-bottom: 6px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.news-card-body h3 a { color: var(--text-dark); }
.news-card-body h3 a:hover { color: var(--primary); }
.news-card-body p { font-size: 14px; color: var(--text-secondary); line-height: 1.5; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; margin-bottom: 10px; }
.news-card-meta { display: flex; align-items: center; gap: 12px; font-size: 13px; color: var(--text-secondary); }
.news-card-meta .badge { font-size: 11px; padding: 2px 10px; }
.news-empty { text-align: center; padding: 60px 20px; color: var(--text-secondary); }
.news-empty .fa { font-size: 48px; color: var(--border); margin-bottom: 16px; }
@media (max-width: 768px) { .news-card { flex-direction: column; gap: 16px; padding: 18px; } .news-card-img { flex: none; width: 100%; height: 160px; } }
/* ===== FAQ ===== */
.faq-section { background: var(--bg-card); }
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid var(--border); padding: 6px 0; }
.faq-question { display: flex; justify-content: space-between; align-items: center; padding: 18px 4px; cursor: pointer; font-size: 17px; font-weight: 600; color: var(--text-dark); transition: var(--transition); background: none; width: 100%; text-align: left; }
.faq-question:hover { color: var(--primary); }
.faq-question .fa { font-size: 18px; color: var(--text-secondary); transition: var(--transition); }
.faq-item.active .fa-chevron-down { transform: rotate(180deg); color: var(--primary); }
.faq-answer { max-height: 0; overflow: hidden; transition: max-height 0.4s ease, padding 0.3s ease; padding: 0 4px; }
.faq-item.active .faq-answer { max-height: 400px; padding: 0 4px 20px 4px; }
.faq-answer p { font-size: 15px; color: var(--text-secondary); line-height: 1.7; margin-bottom: 0; }
/* ===== CTA Banner ===== */
.cta-banner { background: linear-gradient(135deg, var(--primary), var(--secondary)); padding: 80px 0; text-align: center; position: relative; overflow: hidden; }
.cta-banner::before { content: ''; position: absolute; inset: 0; background: radial-gradient(ellipse at 70% 30%, rgba(255,255,255,0.15) 0%, transparent 60%); pointer-events: none; }
.cta-banner .container { position: relative; z-index: 2; }
.cta-banner h2 { font-size: 36px; color: #fff; margin-bottom: 12px; }
.cta-banner p { font-size: 18px; color: rgba(255,255,255,0.85); max-width: 560px; margin: 0 auto 28px; }
.cta-banner .btn { background: #fff; color: var(--primary); border-color: #fff; }
.cta-banner .btn:hover { background: #F3F4F6; color: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(0,0,0,0.2); }
@media (max-width: 768px) { .cta-banner { padding: 50px 0; } .cta-banner h2 { font-size: 26px; } .cta-banner p { font-size: 16px; } }
/* ===== Footer ===== */
.footer { background: var(--bg-dark); color: rgba(255,255,255,0.7); padding: 60px 0 30px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .footer-logo { font-size: 22px; font-weight: 700; color: #fff; margin-bottom: 12px; display: flex; align-items: center; gap: 10px; }
.footer-brand .footer-logo .logo-icon { width: 32px; height: 32px; background: linear-gradient(135deg, var(--primary), var(--secondary)); border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center; color: #fff; font-size: 16px; font-weight: 700; }
.footer-brand p { font-size: 14px; color: rgba(255,255,255,0.55); line-height: 1.7; max-width: 300px; }
.footer-col h4 { font-size: 16px; color: #fff; margin-bottom: 16px; font-weight: 600; }
.footer-col a { display: block; font-size: 14px; color: rgba(255,255,255,0.55); padding: 5px 0; transition: var(--transition); }
.footer-col a:hover { color: #fff; padding-left: 4px; }
.footer-social { display: flex; gap: 12px; margin-top: 16px; }
.footer-social a { width: 36px; height: 36px; border-radius: 50%; background: rgba(255,255,255,0.08); display: flex; align-items: center; justify-content: center; color: rgba(255,255,255,0.6); font-size: 16px; transition: var(--transition); }
.footer-social a:hover { background: var(--primary); color: #fff; }
.footer-bottom { border-top: 1px solid rgba(255,255,255,0.08); padding-top: 24px; display: flex; justify-content: space-between; flex-wrap: wrap; gap: 12px; font-size: 13px; color: rgba(255,255,255,0.4); }
.footer-bottom a { color: rgba(255,255,255,0.4); }
.footer-bottom a:hover { color: rgba(255,255,255,0.7); }
@media (max-width: 900px) { .footer-grid { grid-template-columns: repeat(2, 1fr); gap: 32px; } }
@media (max-width: 768px) { .footer-grid { grid-template-columns: 1fr; gap: 28px; } .footer-bottom { flex-direction: column; text-align: center; } }
/* ===== Back to Top ===== */
.back-to-top { position: fixed; bottom: 32px; right: 32px; width: 48px; height: 48px; border-radius: 50%; background: var(--primary); color: #fff; font-size: 20px; display: flex; align-items: center; justify-content: center; box-shadow: var(--shadow-lg); transition: var(--transition); opacity: 0; visibility: hidden; transform: translateY(12px); z-index: 999; border: none; }
.back-to-top.visible { opacity: 1; visibility: visible; transform: translateY(0); }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-3px); box-shadow: var(--shadow-xl); }
@media (max-width: 768px) { .back-to-top { bottom: 20px; right: 20px; width: 42px; height: 42px; font-size: 17px; } }
/* ===== Utility ===== */
.text-center { text-align: center; }
.mt-8 { margin-top: 8px; }
.mt-16 { margin-top: 16px; }
.mt-24 { margin-top: 24px; }
.mt-32 { margin-top: 32px; }
.mb-16 { margin-bottom: 16px; }
.mb-24 { margin-bottom: 24px; }
.mb-32 { margin-bottom: 32px; }
/* ===== Animations ===== */
@keyframes fadeInUp { from { opacity: 0; transform: translateY(30px); } to { opacity: 1; transform: translateY(0); } }
.fade-in-up { animation: fadeInUp 0.6s ease forwards; }
.delay-1 { animation-delay: 0.1s; }
.delay-2 { animation-delay: 0.2s; }
.delay-3 { animation-delay: 0.3s; }
.delay-4 { animation-delay: 0.4s; }

/* roulang page: category1 */
/* ===== Design Variables ===== */
        :root {
            --primary: #2563EB;
            --primary-dark: #1D4ED8;
            --primary-light: #3B82F6;
            --secondary: #F59E0B;
            --secondary-dark: #D97706;
            --secondary-light: #FBBF24;
            --bg-body: #F9FAFB;
            --bg-card: #FFFFFF;
            --bg-dark: #1F2937;
            --bg-dark-light: #374151;
            --text-primary: #111827;
            --text-body: #1F2937;
            --text-muted: #6B7280;
            --text-light: #9CA3AF;
            --text-white: #FFFFFF;
            --border: #E5E7EB;
            --border-focus: #2563EB;
            --radius-sm: 8px;
            --radius-md: 12px;
            --radius-lg: 16px;
            --radius-xl: 20px;
            --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
            --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
            --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
            --shadow-xl: 0 20px 25px -5px rgba(0,0,0,0.1), 0 8px 10px -6px rgba(0,0,0,0.1);
            --shadow-card-hover: 0 20px 25px -5px rgba(37,99,235,0.12), 0 8px 10px -6px rgba(37,99,235,0.08);
            --font-family: 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --container-max: 1200px;
            --header-height: 64px;
            --spacer-section: 100px;
            --spacer-section-mobile: 60px;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
        body {
            font-family: var(--font-family);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-body);
            background-color: var(--bg-body);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        img { max-width: 100%; height: auto; display: block; }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        ul, ol { list-style: none; }
        button, input, textarea { font-family: inherit; font-size: inherit; outline: none; border: none; }
        button { cursor: pointer; background: none; }
        h1, h2, h3, h4, h5, h6 { color: var(--text-primary); font-weight: 700; line-height: 1.3; }
        h1 { font-size: 42px; }
        h2 { font-size: 32px; }
        h3 { font-size: 24px; font-weight: 600; }
        h4 { font-size: 18px; font-weight: 600; }
        p { color: var(--text-body); margin-bottom: 16px; }
        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 20px;
        }
        .section { padding: var(--spacer-section) 0; }
        .section-title {
            text-align: center;
            margin-bottom: 48px;
        }
        .section-title h2 { margin-bottom: 12px; }
        .section-title p {
            max-width: 640px;
            margin: 0 auto;
            color: var(--text-muted);
            font-size: 18px;
        }
        .text-gradient {
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }

        /* ===== Buttons ===== */
        .btn {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 12px 28px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 16px;
            transition: var(--transition);
            border: 2px solid transparent;
            white-space: nowrap;
        }
        .btn-primary {
            background: var(--primary);
            color: var(--text-white);
            border-color: var(--primary);
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            border-color: var(--primary-dark);
            color: var(--text-white);
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(37,99,235,0.35);
        }
        .btn-secondary {
            background: var(--secondary);
            color: var(--text-white);
            border-color: var(--secondary);
        }
        .btn-secondary:hover {
            background: var(--secondary-dark);
            border-color: var(--secondary-dark);
            color: var(--text-white);
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(245,158,11,0.35);
        }
        .btn-outline {
            background: transparent;
            color: var(--text-white);
            border-color: var(--text-white);
        }
        .btn-outline:hover {
            background: var(--text-white);
            color: var(--primary);
            transform: translateY(-2px);
        }
        .btn-white {
            background: var(--text-white);
            color: var(--primary);
            border-color: var(--text-white);
        }
        .btn-white:hover {
            background: var(--bg-body);
            color: var(--primary-dark);
            transform: translateY(-2px);
            box-shadow: 0 8px 20px rgba(255,255,255,0.3);
        }
        .btn-lg { padding: 16px 36px; font-size: 18px; border-radius: var(--radius-md); }
        .btn-sm { padding: 8px 20px; font-size: 14px; }

        /* ===== Badge / Tag ===== */
        .badge {
            display: inline-block;
            padding: 4px 14px;
            border-radius: 20px;
            font-size: 13px;
            font-weight: 600;
            background: var(--primary);
            color: var(--text-white);
            letter-spacing: 0.3px;
        }
        .badge-secondary { background: var(--secondary); }
        .badge-soft {
            background: rgba(37,99,235,0.1);
            color: var(--primary);
        }
        .badge-hot {
            background: #EF4444;
            color: #fff;
        }
        .badge-new {
            background: #10B981;
            color: #fff;
        }

        /* ===== Header / Nav ===== */
        .header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            height: var(--header-height);
            background: rgba(255,255,255,0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid rgba(229,231,235,0.6);
            transition: var(--transition);
        }
        .header.scrolled { box-shadow: 0 4px 20px rgba(0,0,0,0.06); }
        .header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 100%;
        }
        .logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 22px;
            font-weight: 700;
            color: var(--text-primary);
            text-decoration: none;
        }
        .logo:hover { color: var(--text-primary); }
        .logo-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            border-radius: var(--radius-sm);
            color: #fff;
            font-weight: 800;
            font-size: 18px;
        }
        .logo-text { background: linear-gradient(135deg, var(--primary), var(--secondary)); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
        .header-nav { display: flex; align-items: center; gap: 32px; }
        .header-nav a {
            color: var(--text-muted);
            font-weight: 500;
            font-size: 15px;
            position: relative;
            padding: 4px 0;
            transition: var(--transition);
        }
        .header-nav a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--primary);
            border-radius: 2px;
            transition: var(--transition);
        }
        .header-nav a:hover { color: var(--text-primary); }
        .header-nav a:hover::after { width: 100%; }
        .header-nav a.active { color: var(--primary); }
        .header-nav a.active::after { width: 100%; }
        .header-cta { margin-left: 8px; }
        .header-cta .btn { padding: 10px 24px; font-size: 14px; }

        /* Hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 5px;
            cursor: pointer;
            padding: 8px;
            background: none;
            border: none;
        }
        .hamburger span {
            width: 26px;
            height: 2.5px;
            background: var(--text-primary);
            border-radius: 4px;
            transition: var(--transition);
        }
        .hamburger.active span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
        .hamburger.active span:nth-child(2) { opacity: 0; }
        .hamburger.active span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

        /* ===== Hero ===== */
        .hero {
            position: relative;
            min-height: 620px;
            display: flex;
            align-items: center;
            margin-top: var(--header-height);
            background: linear-gradient(135deg, rgba(37,99,235,0.92), rgba(245,158,11,0.85)), url('/assets/images/backpic/back-1.png') center center / cover no-repeat;
            overflow: hidden;
        }
        .hero::before {
            content: '';
            position: absolute;
            top: -50%;
            right: -20%;
            width: 600px;
            height: 600px;
            background: radial-gradient(circle, rgba(255,255,255,0.08) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .hero::after {
            content: '';
            position: absolute;
            bottom: -30%;
            left: -10%;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(255,255,255,0.05) 0%, transparent 70%);
            border-radius: 50%;
            pointer-events: none;
        }
        .hero .container { position: relative; z-index: 2; width: 100%; }
        .hero-content { max-width: 720px; }
        .hero-badge {
            display: inline-block;
            padding: 6px 18px;
            border-radius: 20px;
            background: rgba(255,255,255,0.15);
            color: #fff;
            font-size: 14px;
            font-weight: 500;
            backdrop-filter: blur(4px);
            margin-bottom: 20px;
            border: 1px solid rgba(255,255,255,0.2);
        }
        .hero h1 {
            font-size: 48px;
            color: var(--text-white);
            line-height: 1.2;
            margin-bottom: 20px;
            font-weight: 800;
        }
        .hero h1 .highlight { background: linear-gradient(135deg, #FCD34D, #F59E0B); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
        .hero p {
            font-size: 18px;
            color: rgba(255,255,255,0.9);
            max-width: 600px;
            margin-bottom: 32px;
            line-height: 1.8;
        }
        .hero-actions { display: flex; gap: 16px; flex-wrap: wrap; }
        .hero-stats {
            display: flex;
            gap: 40px;
            margin-top: 48px;
            padding-top: 32px;
            border-top: 1px solid rgba(255,255,255,0.15);
        }
        .hero-stat { text-align: left; }
        .hero-stat .num {
            font-size: 32px;
            font-weight: 800;
            color: var(--text-white);
            line-height: 1.2;
        }
        .hero-stat .label {
            font-size: 14px;
            color: rgba(255,255,255,0.7);
            margin-top: 4px;
        }

        /* ===== Core Capabilities ===== */
        .capabilities { background: var(--bg-card); }
        .caps-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }
        .cap-card {
            background: var(--bg-card);
            border: 1px solid var(--border);
            border-radius: var(--radius-lg);
            padding: 32px 24px 28px;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }
        .cap-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 4px;
            background: linear-gradient(90deg, var(--primary), var(--secondary));
            opacity: 0;
            transition: var(--transition);
        }
        .cap-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-card-hover);
            border-color: transparent;
        }
        .cap-card:hover::before { opacity: 1; }
        .cap-icon {
            width: 56px;
            height: 56px;
            border-radius: var(--radius-md);
            background: rgba(37,99,235,0.08);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 26px;
            color: var(--primary);
            margin-bottom: 18px;
            transition: var(--transition);
        }
        .cap-card:hover .cap-icon { background: var(--primary); color: #fff; }
        .cap-card h3 { font-size: 20px; margin-bottom: 10px; }
        .cap-card p { font-size: 14px; color: var(--text-muted); margin-bottom: 0; line-height: 1.7; }
        .cap-card .badge-float {
            position: absolute;
            top: 16px;
            right: 16px;
        }

        /* ===== Scenarios ===== */
        .scenarios { background: var(--bg-body); }
        .scenario-block {
            display: flex;
            align-items: center;
            gap: 60px;
            margin-bottom: 80px;
        }
        .scenario-block:last-child { margin-bottom: 0; }
        .scenario-block.reverse { flex-direction: row-reverse; }
        .scenario-img {
            flex: 0 0 48%;
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow-lg);
        }
        .scenario-img img {
            width: 100%;
            height: 320px;
            object-fit: cover;
            transition: var(--transition);
        }
        .scenario-img:hover img { transform: scale(1.03); }
        .scenario-text { flex: 1; }
        .scenario-text .badge { margin-bottom: 12px; }
        .scenario-text h3 { font-size: 26px; margin-bottom: 12px; }
        .scenario-text p { color: var(--text-muted); font-size: 16px; line-height: 1.8; margin-bottom: 20px; }
        .scenario-text .features { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 16px; }
        .scenario-text .features li {
            display: flex;
            align-items: center;
            gap: 6px;
            font-size: 14px;
            color: var(--text-body);
            background: rgba(37,99,235,0.06);
            padding: 6px 14px;
            border-radius: 20px;
        }
        .scenario-text .features li i { color: var(--primary); font-size: 12px; }

        /* ===== Process / Timeline ===== */
        .process {
            background: linear-gradient(135deg, #1E293B, #1F2937);
            color: var(--text-white);
        }
        .process .section-title h2 { color: var(--text-white); }
        .process .section-title p { color: rgba(255,255,255,0.7); }
        .timeline {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
            position: relative;
        }
        .timeline::before {
            content: '';
            position: absolute;
            top: 40px;
            left: 10%;
            right: 10%;
            height: 2px;
            background: linear-gradient(90deg, var(--primary), var(--secondary), var(--primary));
            opacity: 0.4;
        }
        .step {
            text-align: center;
            position: relative;
            padding-top: 20px;
        }
        .step-number {
            width: 56px;
            height: 56px;
            border-radius: 50%;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            color: #fff;
            font-size: 22px;
            font-weight: 700;
            display: flex;
            align-items: center;
            justify-content: center;
            margin: 0 auto 20px;
            position: relative;
            z-index: 2;
            box-shadow: 0 0 0 6px rgba(37,99,235,0.2);
        }
        .step h4 { color: var(--text-white); font-size: 18px; margin-bottom: 8px; }
        .step p { color: rgba(255,255,255,0.65); font-size: 14px; margin-bottom: 0; line-height: 1.7; }

        /* ===== Data Stats ===== */
        .stats-section {
            background: var(--bg-card);
            border-top: 1px solid var(--border);
            border-bottom: 1px solid var(--border);
        }
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 32px;
            text-align: center;
        }
        .stat-item { padding: 20px 0; }
        .stat-item .num {
            font-size: 40px;
            font-weight: 800;
            background: linear-gradient(135deg, var(--primary), var(--secondary));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            line-height: 1.2;
        }
        .stat-item .label { font-size: 15px; color: var(--text-muted); margin-top: 6px; }
        .stat-item .badge { margin-top: 8px; }

        /* ===== FAQ ===== */
        .faq-section { background: var(--bg-body); }
        .faq-list { max-width: 800px; margin: 0 auto; }
        .faq-item {
            background: var(--bg-card);
            border: 1px solid var(--border);
            border-radius: var(--radius-md);
            margin-bottom: 12px;
            overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover { border-color: var(--primary-light); }
        .faq-question {
            width: 100%;
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 20px 24px;
            font-size: 16px;
            font-weight: 600;
            color: var(--text-primary);
            background: none;
            text-align: left;
            transition: var(--transition);
            gap: 16px;
        }
        .faq-question:hover { color: var(--primary); }
        .faq-question .icon {
            font-size: 18px;
            color: var(--primary);
            flex-shrink: 0;
            transition: var(--transition);
        }
        .faq-item.active .faq-question .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-item.active .faq-answer {
            max-height: 300px;
            padding: 0 24px 20px;
        }
        .faq-answer p { font-size: 15px; color: var(--text-muted); line-height: 1.8; margin-bottom: 0; }

        /* ===== CTA Banner ===== */
        .cta-banner {
            background: linear-gradient(135deg, #2563EB, #F59E0B);
            padding: 80px 0;
            text-align: center;
            position: relative;
            overflow: hidden;
        }
        .cta-banner::before {
            content: '';
            position: absolute;
            top: -40%;
            left: -20%;
            width: 500px;
            height: 500px;
            background: radial-gradient(circle, rgba(255,255,255,0.1) 0%, transparent 70%);
            border-radius: 50%;
        }
        .cta-banner::after {
            content: '';
            position: absolute;
            bottom: -30%;
            right: -10%;
            width: 400px;
            height: 400px;
            background: radial-gradient(circle, rgba(255,255,255,0.06) 0%, transparent 70%);
            border-radius: 50%;
        }
        .cta-banner .container { position: relative; z-index: 2; }
        .cta-banner h2 {
            color: var(--text-white);
            font-size: 36px;
            margin-bottom: 16px;
        }
        .cta-banner p {
            color: rgba(255,255,255,0.85);
            font-size: 18px;
            max-width: 600px;
            margin: 0 auto 32px;
        }
        .cta-banner .btn-white:hover { box-shadow: 0 8px 30px rgba(0,0,0,0.2); }

        /* ===== Footer ===== */
        .footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.7);
            padding: 60px 0 0;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr 1fr;
            gap: 40px;
            padding-bottom: 40px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .footer-brand .footer-logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 22px;
            font-weight: 700;
            color: var(--text-white);
            margin-bottom: 16px;
        }
        .footer-brand .footer-logo .logo-icon { width: 36px; height: 36px; font-size: 18px; }
        .footer-brand p { font-size: 14px; color: rgba(255,255,255,0.6); line-height: 1.8; margin-bottom: 20px; max-width: 380px; }
        .footer-social { display: flex; gap: 12px; }
        .footer-social a {
            width: 38px;
            height: 38px;
            border-radius: 50%;
            background: rgba(255,255,255,0.08);
            display: flex;
            align-items: center;
            justify-content: center;
            color: rgba(255,255,255,0.6);
            font-size: 16px;
            transition: var(--transition);
        }
        .footer-social a:hover { background: var(--primary); color: #fff; transform: translateY(-2px); }
        .footer-col h4 {
            color: var(--text-white);
            font-size: 16px;
            font-weight: 600;
            margin-bottom: 16px;
        }
        .footer-col a {
            display: block;
            color: rgba(255,255,255,0.55);
            font-size: 14px;
            padding: 4px 0;
            transition: var(--transition);
        }
        .footer-col a:hover { color: var(--secondary); padding-left: 4px; }
        .footer-bottom {
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: 24px 0;
            font-size: 13px;
            color: rgba(255,255,255,0.4);
            flex-wrap: wrap;
            gap: 12px;
        }
        .footer-bottom a { color: rgba(255,255,255,0.5); }
        .footer-bottom a:hover { color: var(--secondary); }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .caps-grid { grid-template-columns: repeat(2, 1fr); }
            .timeline { grid-template-columns: repeat(2, 1fr); }
            .timeline::before { display: none; }
            .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
            .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
            .scenario-block { gap: 40px; }
            .scenario-img { flex: 0 0 45%; }
        }

        @media (max-width: 768px) {
            :root { --spacer-section: var(--spacer-section-mobile); }
            h1 { font-size: 32px; }
            h2 { font-size: 26px; }
            h3 { font-size: 20px; }
            .section-title { margin-bottom: 32px; }

            .hamburger { display: flex; }
            .header-nav {
                position: fixed;
                top: var(--header-height);
                left: 0;
                right: 0;
                background: var(--bg-card);
                flex-direction: column;
                padding: 24px 20px;
                box-shadow: var(--shadow-lg);
                gap: 16px;
                transform: translateY(-120%);
                opacity: 0;
                transition: var(--transition);
                border-bottom: 2px solid var(--border);
                align-items: stretch;
            }
            .header-nav.open {
                transform: translateY(0);
                opacity: 1;
            }
            .header-nav a { font-size: 16px; padding: 10px 0; }
            .header-nav a::after { display: none; }
            .header-cta { margin-left: 0; }
            .header-cta .btn { width: 100%; justify-content: center; }

            .hero { min-height: 480px; }
            .hero h1 { font-size: 34px; }
            .hero p { font-size: 16px; }
            .hero-stats { gap: 24px; flex-wrap: wrap; }
            .hero-stat .num { font-size: 26px; }

            .caps-grid { grid-template-columns: 1fr; gap: 16px; }

            .scenario-block {
                flex-direction: column !important;
                gap: 24px;
                margin-bottom: 48px;
            }
            .scenario-img { flex: none; width: 100%; }
            .scenario-img img { height: 220px; }
            .scenario-text h3 { font-size: 22px; }

            .timeline { grid-template-columns: 1fr; gap: 32px; }
            .step { padding-top: 0; }
            .step-number { width: 48px; height: 48px; font-size: 18px; }

            .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 16px; }
            .stat-item .num { font-size: 32px; }

            .faq-question { padding: 16px 18px; font-size: 15px; }
            .faq-answer { padding: 0 18px; }
            .faq-item.active .faq-answer { padding: 0 18px 16px; }

            .cta-banner { padding: 60px 0; }
            .cta-banner h2 { font-size: 28px; }
            .cta-banner p { font-size: 16px; }

            .footer-grid { grid-template-columns: 1fr; gap: 24px; }
            .footer-bottom { flex-direction: column; text-align: center; }
        }

        @media (max-width: 520px) {
            .container { padding: 0 16px; }
            .hero h1 { font-size: 28px; }
            .hero-actions { flex-direction: column; }
            .hero-actions .btn { width: 100%; justify-content: center; }
            .hero-stats { flex-direction: column; gap: 16px; }
            .scenario-text .features li { font-size: 13px; padding: 4px 12px; }
            .stats-grid { grid-template-columns: 1fr 1fr; }
        }

        /* ===== Animations ===== */
        @keyframes fadeInUp {
            from { opacity: 0; transform: translateY(30px); }
            to { opacity: 1; transform: translateY(0); }
        }
        .animate-in {
            animation: fadeInUp 0.6s ease forwards;
        }
        .delay-1 { animation-delay: 0.1s; }
        .delay-2 { animation-delay: 0.2s; }
        .delay-3 { animation-delay: 0.3s; }
        .delay-4 { animation-delay: 0.4s; }

/* roulang page: article */
/* ===== 设计变量 ===== */
        :root {
            --primary: #2563EB;
            --primary-dark: #1D4ED8;
            --primary-light: #60A5FA;
            --accent: #F59E0B;
            --accent-dark: #D97706;
            --accent-light: #FCD34D;
            --bg-page: #F9FAFB;
            --bg-card: #FFFFFF;
            --bg-dark: #1F2937;
            --bg-dark-light: #374151;
            --text-dark: #111827;
            --text-body: #1F2937;
            --text-secondary: #6B7280;
            --text-light: #9CA3AF;
            --border: #E5E7EB;
            --border-focus: #2563EB;
            --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
            --shadow: 0 4px 6px -1px rgba(0,0,0,0.1), 0 2px 4px -2px rgba(0,0,0,0.1);
            --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1), 0 4px 6px -4px rgba(0,0,0,0.1);
            --shadow-hover: 0 12px 24px -8px rgba(0,0,0,0.15);
            --radius-sm: 8px;
            --radius: 12px;
            --radius-lg: 16px;
            --radius-xl: 20px;
            --font-family: 'PingFang SC', 'Microsoft YaHei', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
            --max-width: 1200px;
            --header-height: 64px;
            --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
        }

        /* ===== 基础重置 ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

        html { scroll-behavior: smooth; -webkit-font-smoothing: antialiased; }

        body {
            font-family: var(--font-family);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-body);
            background: var(--bg-page);
            padding-top: var(--header-height);
        }

        a { color: var(--primary); text-decoration: none; transition: color var(--transition); }
        a:hover { color: var(--primary-dark); }
        a:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; border-radius: 4px; }

        img { max-width: 100%; height: auto; display: block; border-radius: var(--radius); }
        button, input, textarea { font-family: inherit; font-size: inherit; }
        ul, ol { padding-left: 1.5em; }
        h1, h2, h3, h4, h5, h6 { color: var(--text-dark); line-height: 1.25; font-weight: 700; }

        /* ===== 容器 ===== */
        .container {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 20px;
        }

        /* ===== Header / 导航 ===== */
        .header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            height: var(--header-height);
            background: rgba(255,255,255,0.96);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border);
            z-index: 1000;
            transition: box-shadow var(--transition);
        }
        .header.scrolled { box-shadow: var(--shadow); }
        .header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 100%;
        }

        .header-logo {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 22px;
            font-weight: 700;
            color: var(--text-dark);
            letter-spacing: -0.3px;
            flex-shrink: 0;
        }
        .header-logo .logo-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: #fff;
            border-radius: var(--radius-sm);
            font-size: 18px;
            font-weight: 700;
        }
        .header-logo:hover { color: var(--text-dark); opacity: 0.9; }

        .header-nav {
            display: flex;
            align-items: center;
            gap: 32px;
        }
        .header-nav a {
            font-size: 15px;
            font-weight: 500;
            color: var(--text-secondary);
            padding: 6px 0;
            border-bottom: 2px solid transparent;
            transition: color var(--transition), border-color var(--transition);
            position: relative;
        }
        .header-nav a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            right: 0;
            height: 2px;
            background: var(--primary);
            transform: scaleX(0);
            transition: transform var(--transition);
        }
        .header-nav a:hover { color: var(--text-dark); }
        .header-nav a:hover::after { transform: scaleX(1); }
        .header-nav a.active { color: var(--primary); font-weight: 600; }
        .header-nav a.active::after { transform: scaleX(1); background: var(--primary); }

        .header-cta {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: linear-gradient(135deg, var(--primary), var(--primary-dark));
            color: #fff;
            padding: 10px 24px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            font-size: 14px;
            border: none;
            cursor: pointer;
            transition: background var(--transition), transform var(--transition), box-shadow var(--transition);
            box-shadow: 0 2px 8px rgba(37,99,235,0.3);
            white-space: nowrap;
        }
        .header-cta:hover {
            background: linear-gradient(135deg, var(--primary-dark), #1E40AF);
            transform: translateY(-1px);
            box-shadow: 0 6px 16px rgba(37,99,235,0.4);
            color: #fff;
        }
        .header-cta i { font-size: 14px; }

        /* 汉堡菜单 */
        .menu-toggle {
            display: none;
            flex-direction: column;
            gap: 5px;
            background: none;
            border: none;
            cursor: pointer;
            padding: 8px;
            border-radius: var(--radius-sm);
            transition: background var(--transition);
        }
        .menu-toggle:hover { background: var(--border); }
        .menu-toggle span {
            width: 24px;
            height: 2px;
            background: var(--text-dark);
            border-radius: 2px;
            transition: all var(--transition);
        }
        .menu-toggle.open span:nth-child(1) { transform: rotate(45deg) translate(5px, 5px); }
        .menu-toggle.open span:nth-child(2) { opacity: 0; }
        .menu-toggle.open span:nth-child(3) { transform: rotate(-45deg) translate(5px, -5px); }

        /* ===== 面包屑 ===== */
        .breadcrumb {
            background: var(--bg-card);
            border-bottom: 1px solid var(--border);
            padding: 12px 0;
            font-size: 13px;
            color: var(--text-secondary);
        }
        .breadcrumb .container { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
        .breadcrumb a { color: var(--text-secondary); }
        .breadcrumb a:hover { color: var(--primary); }
        .breadcrumb .sep { color: var(--text-light); user-select: none; }
        .breadcrumb .current { color: var(--text-body); font-weight: 500; }

        /* ===== 文章主体 ===== */
        .article-main {
            padding: 48px 0 64px;
        }
        .article-wrapper {
            max-width: 860px;
            margin: 0 auto;
            background: var(--bg-card);
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow);
            padding: 48px 56px;
        }
        .article-header {
            margin-bottom: 36px;
            padding-bottom: 28px;
            border-bottom: 1px solid var(--border);
        }
        .article-header h1 {
            font-size: 36px;
            line-height: 1.3;
            margin-bottom: 16px;
            color: var(--text-dark);
            letter-spacing: -0.5px;
        }
        .article-meta {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 12px 20px;
            font-size: 14px;
            color: var(--text-secondary);
        }
        .article-meta .tag {
            display: inline-block;
            background: rgba(37,99,235,0.1);
            color: var(--primary);
            padding: 4px 14px;
            border-radius: 20px;
            font-size: 12px;
            font-weight: 600;
            letter-spacing: 0.3px;
        }
        .article-meta .date {
            display: flex;
            align-items: center;
            gap: 6px;
        }
        .article-meta .date i { font-size: 13px; }

        .article-feature-img {
            margin-bottom: 32px;
            border-radius: var(--radius);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
        }
        .article-feature-img img {
            width: 100%;
            aspect-ratio: 16 / 9;
            object-fit: cover;
        }

        .article-content {
            font-size: 17px;
            line-height: 1.9;
            color: var(--text-body);
        }
        .article-content h2 { font-size: 26px; margin: 36px 0 16px; padding-bottom: 8px; border-bottom: 1px solid var(--border); }
        .article-content h3 { font-size: 21px; margin: 28px 0 12px; }
        .article-content h4 { font-size: 18px; margin: 24px 0 10px; font-weight: 600; }
        .article-content p { margin-bottom: 18px; }
        .article-content ul, .article-content ol { margin-bottom: 18px; }
        .article-content li { margin-bottom: 8px; }
        .article-content blockquote {
            border-left: 4px solid var(--primary);
            background: rgba(37,99,235,0.04);
            padding: 16px 24px;
            margin: 24px 0;
            border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
            color: var(--text-secondary);
            font-style: normal;
        }
        .article-content blockquote p:last-child { margin-bottom: 0; }
        .article-content img {
            margin: 24px auto;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            max-width: 100%;
        }
        .article-content figure { margin: 28px 0; text-align: center; }
        .article-content figure figcaption { font-size: 13px; color: var(--text-light); margin-top: 8px; }
        .article-content a { color: var(--primary); text-decoration: underline; text-underline-offset: 2px; }
        .article-content a:hover { color: var(--primary-dark); }

        /* ===== 内容未找到 ===== */
        .not-found-box {
            text-align: center;
            padding: 80px 40px;
            background: var(--bg-card);
            border-radius: var(--radius-lg);
            box-shadow: var(--shadow);
        }
        .not-found-box .nf-icon {
            font-size: 64px;
            color: var(--text-light);
            margin-bottom: 20px;
        }
        .not-found-box h2 {
            font-size: 28px;
            margin-bottom: 12px;
        }
        .not-found-box p {
            color: var(--text-secondary);
            margin-bottom: 28px;
        }

        /* ===== 相关推荐 ===== */
        .related-section {
            padding: 64px 0 80px;
            background: var(--bg-page);
        }
        .related-section .section-title {
            font-size: 28px;
            text-align: center;
            margin-bottom: 40px;
            color: var(--text-dark);
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }
        .related-card {
            background: var(--bg-card);
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            overflow: hidden;
            transition: transform var(--transition), box-shadow var(--transition);
        }
        .related-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-hover);
        }
        .related-card .rc-img {
            width: 100%;
            aspect-ratio: 16 / 9;
            object-fit: cover;
        }
        .related-card .rc-body {
            padding: 20px 22px 24px;
        }
        .related-card .rc-body h3 {
            font-size: 17px;
            font-weight: 600;
            margin-bottom: 8px;
            color: var(--text-dark);
            line-height: 1.4;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }
        .related-card .rc-body p {
            font-size: 14px;
            color: var(--text-secondary);
            line-height: 1.6;
            display: -webkit-box;
            -webkit-line-clamp: 2;
            -webkit-box-orient: vertical;
            overflow: hidden;
            margin-bottom: 12px;
        }
        .related-card .rc-meta {
            display: flex;
            align-items: center;
            justify-content: space-between;
            font-size: 12px;
            color: var(--text-light);
        }
        .related-card .rc-meta .rc-tag {
            background: rgba(37,99,235,0.08);
            color: var(--primary);
            padding: 2px 12px;
            border-radius: 12px;
            font-weight: 500;
        }
        .related-cta {
            text-align: center;
            margin-top: 40px;
        }
        .related-cta .btn-back {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: var(--bg-card);
            color: var(--text-body);
            border: 1px solid var(--border);
            padding: 12px 32px;
            border-radius: var(--radius-sm);
            font-weight: 500;
            transition: all var(--transition);
        }
        .related-cta .btn-back:hover {
            border-color: var(--primary);
            color: var(--primary);
            background: rgba(37,99,235,0.02);
            transform: translateY(-2px);
            box-shadow: var(--shadow);
        }

        /* ===== Footer ===== */
        .footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.85);
            padding: 64px 0 32px;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.6fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer-brand .footer-logo {
            display: flex;
            align-items: center;
            gap: 8px;
            font-size: 22px;
            font-weight: 700;
            color: #fff;
            margin-bottom: 16px;
        }
        .footer-brand .footer-logo .logo-icon {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 36px;
            height: 36px;
            background: linear-gradient(135deg, var(--primary), var(--accent));
            color: #fff;
            border-radius: var(--radius-sm);
            font-size: 18px;
            font-weight: 700;
        }
        .footer-brand p {
            font-size: 14px;
            line-height: 1.7;
            color: rgba(255,255,255,0.6);
            margin-bottom: 20px;
            max-width: 360px;
        }
        .footer-social {
            display: flex;
            gap: 12px;
        }
        .footer-social a {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 38px;
            height: 38px;
            background: rgba(255,255,255,0.08);
            color: rgba(255,255,255,0.7);
            border-radius: var(--radius-sm);
            font-size: 16px;
            transition: background var(--transition), color var(--transition), transform var(--transition);
        }
        .footer-social a:hover {
            background: var(--primary);
            color: #fff;
            transform: translateY(-2px);
        }

        .footer-col h4 {
            font-size: 15px;
            font-weight: 600;
            color: #fff;
            margin-bottom: 18px;
            letter-spacing: 0.5px;
        }
        .footer-col a {
            display: block;
            font-size: 14px;
            color: rgba(255,255,255,0.55);
            padding: 5px 0;
            transition: color var(--transition), padding-left var(--transition);
        }
        .footer-col a:hover { color: #fff; padding-left: 4px; }

        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.08);
            padding-top: 24px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 12px;
            font-size: 13px;
            color: rgba(255,255,255,0.4);
        }
        .footer-bottom a { color: rgba(255,255,255,0.5); }
        .footer-bottom a:hover { color: #fff; }

        /* ===== 响应式 ===== */
        @media (max-width: 1024px) {
            .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
            .related-grid { gap: 20px; }
            .article-wrapper { padding: 36px 32px; }
        }

        @media (max-width: 768px) {
            .header-nav { display: none; }
            .header-nav.mobile-open {
                display: flex;
                flex-direction: column;
                position: fixed;
                top: var(--header-height);
                left: 0;
                right: 0;
                background: var(--bg-card);
                padding: 24px 20px 32px;
                gap: 6px;
                box-shadow: var(--shadow-lg);
                border-bottom: 1px solid var(--border);
                z-index: 999;
                align-items: stretch;
            }
            .header-nav.mobile-open a {
                padding: 12px 16px;
                border-radius: var(--radius-sm);
                border-bottom: none;
                font-size: 16px;
            }
            .header-nav.mobile-open a::after { display: none; }
            .header-nav.mobile-open a:hover { background: var(--bg-page); }
            .header-nav.mobile-open a.active { background: rgba(37,99,235,0.06); color: var(--primary); }
            .header-cta { display: none; }
            .header-cta.mobile-show {
                display: inline-flex;
                margin-top: 12px;
                justify-content: center;
                width: 100%;
            }
            .menu-toggle { display: flex; }

            .article-wrapper { padding: 28px 20px; }
            .article-header h1 { font-size: 26px; }
            .article-content { font-size: 16px; line-height: 1.8; }
            .article-content h2 { font-size: 22px; }
            .article-content h3 { font-size: 18px; }

            .related-grid { grid-template-columns: 1fr; }
            .related-section .section-title { font-size: 22px; }

            .footer-grid { grid-template-columns: 1fr; gap: 28px; }
            .footer-bottom { flex-direction: column; text-align: center; }
            .container { padding: 0 16px; }
            .breadcrumb { font-size: 12px; }
        }

        @media (max-width: 520px) {
            .article-wrapper { padding: 20px 16px; border-radius: var(--radius); }
            .article-header h1 { font-size: 22px; }
            .article-content { font-size: 15px; }
            .not-found-box { padding: 48px 20px; }
            .related-card .rc-body { padding: 16px; }
        }

        /* ===== 工具类 ===== */
        .text-center { text-align: center; }
        .mt-16 { margin-top: 16px; }
        .mb-16 { margin-bottom: 16px; }
        .gap-8 { gap: 8px; }