/* ========== RESET & BASE ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; color: #333; background: #fff; line-height: 1.7; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; }
.container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

/* ========== NAV ========== */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.97); backdrop-filter: blur(12px);
  border-bottom: 1px solid #eee; height: 64px;
}
.nav-inner {
  max-width: 1140px; margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.nav-brand { font-size: 20px; font-weight: 800; color: #1E88E5; display: flex; align-items: center; gap: 6px; }
.nav-brand span { font-size: 24px; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a { font-size: 14px; font-weight: 500; color: #555; transition: color 0.2s; }
.nav-links a:hover, .nav-links a.active { color: #1E88E5; }
.nav-cta {
  background: #1E88E5; color: #fff; border: none; padding: 8px 20px;
  border-radius: 6px; font-size: 14px; font-weight: 600; cursor: pointer;
  transition: background 0.2s;
}
.nav-cta:hover { background: #1565C0; }
.menu-toggle { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: #333; }

/* ========== HERO BANNER ========== */
.hero {
  margin-top: 64px; padding: 60px 0 50px;
  background: linear-gradient(135deg, #E3F2FD 0%, #BBDEFB 50%, #E3F2FD 100%);
  position: relative; overflow: hidden;
}
.hero::after {
  content: ''; position: absolute; right: -60px; top: -40px;
  width: 400px; height: 400px; border-radius: 50%;
  background: radial-gradient(circle, rgba(30,136,229,0.08), transparent 70%);
}
.hero-inner {
  display: flex; align-items: center; gap: 48px; position: relative; z-index: 1;
}
.hero-text { flex: 1; }
.hero-badge {
  display: inline-block; background: #1E88E5; color: #fff;
  font-size: 12px; font-weight: 700; padding: 4px 12px;
  border-radius: 20px; margin-bottom: 16px; letter-spacing: 0.5px;
}
.hero h1 { font-size: 36px; font-weight: 800; line-height: 1.3; color: #1a1a1a; margin-bottom: 16px; }
.hero-sub { font-size: 16px; color: #555; margin-bottom: 8px; }
.hero-features { list-style: none; margin: 16px 0 28px; }
.hero-features li { font-size: 15px; color: #444; padding: 4px 0; display: flex; align-items: center; gap: 8px; }
.hero-features li::before { content: '✅'; font-size: 14px; }
.hero-buttons { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-primary {
  background: #1E88E5; color: #fff; padding: 14px 32px;
  border-radius: 8px; font-size: 16px; font-weight: 700;
  border: none; cursor: pointer; transition: all 0.2s;
  box-shadow: 0 4px 14px rgba(30,136,229,0.3);
}
.btn-primary:hover { background: #1565C0; transform: translateY(-1px); box-shadow: 0 6px 20px rgba(30,136,229,0.4); }
.btn-secondary {
  background: #fff; color: #1E88E5; padding: 14px 28px;
  border-radius: 8px; font-size: 16px; font-weight: 600;
  border: 2px solid #1E88E5; cursor: pointer; transition: all 0.2s;
}
.btn-secondary:hover { background: #E3F2FD; }
.hero-img { flex: 0 0 420px; position: relative; }
.hero-img img {
  width: 100%; border-radius: 12px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.12);
}

/* ========== ADVANTAGES ========== */
.advantages { padding: 60px 0; background: #fff; }
.section-title { text-align: center; font-size: 28px; font-weight: 800; color: #1a1a1a; margin-bottom: 8px; }
.section-subtitle { text-align: center; font-size: 15px; color: #888; margin-bottom: 40px; }
.adv-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 24px; }
.adv-card {
  background: #F8FBFF; border: 1px solid #E8F0FE; border-radius: 12px;
  padding: 28px 22px; text-align: center; transition: all 0.3s;
}
.adv-card:hover { transform: translateY(-4px); box-shadow: 0 8px 30px rgba(30,136,229,0.1); border-color: #1E88E5; }
.adv-icon { font-size: 36px; margin-bottom: 14px; }
.adv-card h3 { font-size: 17px; font-weight: 700; color: #1a1a1a; margin-bottom: 8px; }
.adv-card p { font-size: 13px; color: #777; line-height: 1.6; }

/* ========== VERSION INFO ========== */
.version { padding: 50px 0; background: #FAFCFF; }
.version-card {
  max-width: 700px; margin: 0 auto;
  background: #fff; border-radius: 12px; padding: 36px;
  border: 1px solid #E8F0FE;
}
.version-header { display: flex; align-items: center; gap: 14px; margin-bottom: 24px; }
.version-header h3 { font-size: 20px; font-weight: 700; }
.version-badge { background: #E8F5E9; color: #2E7D32; font-size: 12px; font-weight: 700; padding: 3px 10px; border-radius: 12px; }
.version-list { list-style: none; }
.version-list li {
  display: flex; justify-content: space-between;
  padding: 10px 0; border-bottom: 1px solid #f0f0f0; font-size: 14px;
}
.version-list li:last-child { border-bottom: none; }
.version-list .label { color: #888; }
.version-list .value { color: #333; font-weight: 600; }
.version-desc { margin-top: 20px; font-size: 14px; color: #666; line-height: 1.8; }

/* ========== TUTORIALS ========== */
.tutorials { padding: 60px 0; background: #fff; }
.tut-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.tut-card {
  background: #fff; border-radius: 12px; overflow: hidden;
  border: 1px solid #eee; transition: all 0.3s;
}
.tut-card:hover { transform: translateY(-4px); box-shadow: 0 12px 36px rgba(0,0,0,0.08); }
.tut-thumb { height: 140px; display: flex; align-items: center; justify-content: center; }
.tut-thumb { height: 160px; background: linear-gradient(135deg, #1E88E5, #42A5F5); display: flex; align-items: center; justify-content: center; }
.tut-thumb span { font-size: 48px; }
.tut-body { padding: 20px; }
.tut-tag { display: inline-block; background: #E3F2FD; color: #1E88E5; font-size: 11px; font-weight: 700; padding: 3px 10px; border-radius: 4px; margin-bottom: 10px; }
.tut-body h3 { font-size: 16px; font-weight: 700; color: #1a1a1a; margin-bottom: 8px; line-height: 1.4; }
.tut-body p { font-size: 13px; color: #777; line-height: 1.6; }
.tut-link { display: inline-block; margin-top: 12px; font-size: 13px; color: #1E88E5; font-weight: 600; }

/* ========== FAQ ========== */
.faq { padding: 60px 0; background: #FAFCFF; }
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-item { background: #fff; border: 1px solid #eee; border-radius: 10px; margin-bottom: 12px; overflow: hidden; }
.faq-q {
  padding: 18px 22px; font-size: 15px; font-weight: 600; color: #333;
  cursor: pointer; display: flex; justify-content: space-between; align-items: center;
  transition: background 0.2s;
}
.faq-q:hover { background: #F8FBFF; }
.faq-q::after { content: '▸'; color: #1E88E5; font-size: 14px; transition: transform 0.2s; }
.faq-item.open .faq-q::after { transform: rotate(90deg); }
.faq-a { padding: 0 22px; max-height: 0; overflow: hidden; transition: all 0.3s; }
.faq-item.open .faq-a { max-height: 200px; padding: 0 22px 18px; }
.faq-a p { font-size: 14px; color: #666; line-height: 1.7; }

/* ========== DOWNLOAD CTA ========== */
.dl-section {
  padding: 60px 0;
  background: linear-gradient(135deg, #1E88E5 0%, #1565C0 100%);
  color: #fff; text-align: center;
}
.dl-section h2 { font-size: 28px; font-weight: 800; margin-bottom: 12px; }
.dl-section p { font-size: 15px; opacity: 0.9; max-width: 600px; margin: 0 auto 28px; line-height: 1.7; }
.btn-dl {
  background: #fff; color: #1E88E5; padding: 16px 40px;
  border-radius: 8px; font-size: 18px; font-weight: 800;
  border: none; cursor: pointer; transition: all 0.2s;
  box-shadow: 0 4px 20px rgba(0,0,0,0.15);
}
.btn-dl:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(0,0,0,0.2); }

/* ========== SAFETY ========== */
.safety { padding: 50px 0; background: #fff; }
.safety-card {
  max-width: 700px; margin: 0 auto; background: #FFF8E1;
  border: 1px solid #FFE082; border-radius: 12px; padding: 28px 32px;
}
.safety-card h3 { font-size: 18px; font-weight: 700; color: #F57F17; margin-bottom: 16px; display: flex; align-items: center; gap: 8px; }
.safety-list { list-style: none; }
.safety-list li { font-size: 14px; color: #555; padding: 6px 0; display: flex; align-items: flex-start; gap: 8px; line-height: 1.6; }
.safety-list li::before { content: '⚠️'; flex-shrink: 0; }

/* ========== FOOTER ========== */
.footer { background: #1a1a2e; color: #ccc; padding: 40px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 32px; }
.footer-brand { font-size: 18px; font-weight: 800; color: #fff; margin-bottom: 10px; }
.footer-desc { font-size: 13px; line-height: 1.7; opacity: 0.7; }
.footer-col h4 { font-size: 14px; font-weight: 700; color: #fff; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 13px; color: #aaa; padding: 3px 0; transition: color 0.2s; }
.footer-col a:hover { color: #1E88E5; }
.footer-bottom { border-top: 1px solid #2a2a3e; padding-top: 20px; text-align: center; font-size: 12px; opacity: 0.5; }

/* ========== MOBILE ========== */
.mobile-menu { display: none; position: fixed; top: 64px; left: 0; right: 0; bottom: 0; background: #fff; z-index: 99; padding: 24px; flex-direction: column; gap: 20px; }
.mobile-menu.active { display: flex; }
.mobile-menu a { font-size: 16px; color: #333; font-weight: 500; padding: 8px 0; }
.menu-overlay { display: none; position: fixed; top: 64px; left: 0; right: 0; bottom: 0; background: rgba(0,0,0,0.3); z-index: 98; }
.menu-overlay.active { display: block; }

@media (max-width: 768px) {
  .nav-links, .nav-cta { display: none; }
  .menu-toggle { display: block; }
  .hero-inner { flex-direction: column; text-align: center; }
  .hero h1 { font-size: 26px; }
  .hero-img { flex: none; width: 100%; max-width: 360px; }
  .hero-buttons { justify-content: center; }
  .adv-grid { grid-template-columns: repeat(2, 1fr); }
  .tut-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 480px) {
  .adv-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 22px; }
  .footer-grid { grid-template-columns: 1fr; }
}

/* ========== ARTICLE PAGE ========== */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif; color: #333; background: #fff; line-height: 1.7; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; }
.container { max-width: 1140px; margin: 0 auto; padding: 0 24px; }

/* NAV - same as index */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255,255,255,0.97); backdrop-filter: blur(12px);
  border-bottom: 1px solid #eee; height: 64px;
}
.nav-inner {
  max-width: 1140px; margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; justify-content: space-between; height: 100%;
}
.nav-brand { font-size: 20px; font-weight: 800; color: #1E88E5; display: flex; align-items: center; gap: 6px; }
.nav-brand span { font-size: 24px; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a { font-size: 14px; font-weight: 500; color: #555; transition: color 0.2s; }
.nav-links a:hover { color: #1E88E5; }
.nav-cta {
  background: #1E88E5; color: #fff; border: none; padding: 8px 20px;
  border-radius: 6px; font-size: 14px; font-weight: 600; cursor: pointer; transition: background 0.2s;
}
.nav-cta:hover { background: #1565C0; }
.menu-toggle { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: #333; }

/* BREADCRUMB */
.breadcrumb { margin-top: 80px; padding: 12px 0; font-size: 13px; color: #999; }
.breadcrumb a { color: #1E88E5; }
.breadcrumb span { margin: 0 6px; }

/* ARTICLE LAYOUT */
.article-layout { display: grid; grid-template-columns: 1fr 320px; gap: 40px; padding-bottom: 60px; }

/* MAIN CONTENT */
.article-main {}
.article-header { margin-bottom: 28px; padding-bottom: 20px; border-bottom: 1px solid #eee; }
.article-meta { display: flex; gap: 16px; font-size: 13px; color: #999; margin-bottom: 12px; flex-wrap: wrap; }
.article-meta .tag { background: #E3F2FD; color: #1E88E5; padding: 2px 10px; border-radius: 4px; font-weight: 600; }
.article-title { font-size: 28px; font-weight: 800; color: #1a1a1a; line-height: 1.4; margin-bottom: 10px; }
.article-desc { font-size: 15px; color: #777; line-height: 1.7; }

/* CPA Banner inside article */
.article-cta {
  background: linear-gradient(135deg, #1E88E5, #1565C0);
  color: #fff; border-radius: 10px; padding: 20px 24px;
  margin: 24px 0; display: flex; align-items: center; justify-content: space-between; gap: 16px;
}
.article-cta-text h3 { font-size: 16px; font-weight: 700; margin-bottom: 4px; }
.article-cta-text p { font-size: 13px; opacity: 0.9; }
.btn-cta-sm {
  background: #fff; color: #1E88E5; border: none; padding: 10px 24px;
  border-radius: 6px; font-size: 14px; font-weight: 700; cursor: pointer;
  white-space: nowrap; transition: all 0.2s;
}
.btn-cta-sm:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(0,0,0,0.2); }

/* Article Body */
.article-body { font-size: 16px; line-height: 1.9; color: #333; }
.article-body h2 {
  font-size: 22px; font-weight: 800; color: #1a1a1a; margin: 36px 0 16px;
  padding-left: 14px; border-left: 4px solid #1E88E5;
}
.article-body h3 {
  font-size: 18px; font-weight: 700; color: #1a1a1a; margin: 24px 0 12px;
}
.article-body p { margin-bottom: 16px; }
.article-body ul, .article-body ol { margin: 12px 0 16px 24px; }
.article-body li { margin-bottom: 6px; }
.article-body img {
  border-radius: 8px; margin: 16px 0; display: block;
  box-shadow: 0 4px 16px rgba(0,0,0,0.06);
}
.article-body blockquote {
  border-left: 4px solid #1E88E5; background: #F8FBFF; padding: 16px 20px;
  margin: 20px 0; border-radius: 0 8px 8px 0; color: #555; font-size: 15px;
}
.article-body table {
  width: 100%; border-collapse: collapse; margin: 20px 0; font-size: 14px;
}
.article-body th {
  background: #1E88E5; color: #fff; padding: 10px 14px; text-align: left; font-weight: 600;
}
.article-body td { padding: 10px 14px; border-bottom: 1px solid #eee; }
.article-body tr:nth-child(even) { background: #F8FBFF; }

/* FAQ Section */
.faq-section { margin: 40px 0; }
.faq-section h2 { border-left-color: #FB8C00 !important; }
.faq-item { background: #FAFCFF; border: 1px solid #E8F0FE; border-radius: 8px; margin-bottom: 10px; overflow: hidden; }
.faq-q {
  padding: 14px 18px; font-size: 15px; font-weight: 600; color: #333;
  cursor: pointer; display: flex; justify-content: space-between; align-items: center;
}
.faq-q::after { content: '▸'; color: #1E88E5; font-size: 14px; transition: transform 0.2s; }
.faq-item.open .faq-q::after { transform: rotate(90deg); }
.faq-a { padding: 0 18px; max-height: 0; overflow: hidden; transition: all 0.3s; }
.faq-item.open .faq-a { max-height: 200px; padding: 0 18px 14px; }
.faq-a p { font-size: 14px; color: #666; line-height: 1.7; }

/* SIDEBAR */
.sidebar {}
.sidebar-widget {
  background: #fff; border: 1px solid #eee; border-radius: 10px;
  padding: 20px; margin-bottom: 20px;
}
.sidebar-widget h3 { font-size: 16px; font-weight: 700; color: #1a1a1a; margin-bottom: 14px; padding-bottom: 10px; border-bottom: 2px solid #1E88E5; }

/* Download Card */
.dl-card { text-align: center; }
.dl-card .dl-icon { font-size: 40px; margin-bottom: 10px; }
.dl-card p { font-size: 13px; color: #777; margin-bottom: 14px; line-height: 1.6; }
.btn-dl-side {
  display: block; width: 100%; background: #1E88E5; color: #fff;
  padding: 12px; border-radius: 6px; font-size: 15px; font-weight: 700;
  border: none; cursor: pointer; transition: background 0.2s;
}
.btn-dl-side:hover { background: #1565C0; }

/* Related Articles */
.related-list { list-style: none; }
.related-list li { margin-bottom: 10px; }
.related-list a { font-size: 14px; color: #444; display: flex; align-items: flex-start; gap: 8px; line-height: 1.5; }
.related-list a::before { content: '→'; color: #1E88E5; font-weight: 700; flex-shrink: 0; margin-top: 2px; }
.related-list a:hover { color: #1E88E5; }

/* TOC */
.toc-list { list-style: none; }
.toc-list li { margin-bottom: 6px; }
.toc-list a { font-size: 13px; color: #666; line-height: 1.5; display: block; padding: 4px 0 4px 12px; border-left: 2px solid transparent; transition: all 0.2s; }
.toc-list a:hover { color: #1E88E5; border-left-color: #1E88E5; }

/* FOOTER - same as index */
.footer { background: #1a1a2e; color: #ccc; padding: 40px 0 24px; }
.footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1fr 1fr; gap: 32px; margin-bottom: 32px; }
.footer-brand { font-size: 18px; font-weight: 800; color: #fff; margin-bottom: 10px; }
.footer-desc { font-size: 13px; line-height: 1.7; opacity: 0.7; }
.footer-col h4 { font-size: 14px; font-weight: 700; color: #fff; margin-bottom: 14px; }
.footer-col a { display: block; font-size: 13px; color: #aaa; padding: 3px 0; }
.footer-col a:hover { color: #1E88E5; }
.footer-bottom { border-top: 1px solid #2a2a3e; padding-top: 20px; text-align: center; font-size: 12px; opacity: 0.5; }

/* MOBILE */
.mobile-menu { display: none; position: fixed; top: 64px; left: 0; right: 0; bottom: 0; background: #fff; z-index: 99; padding: 24px; flex-direction: column; gap: 20px; }
.mobile-menu.active { display: flex; }
.mobile-menu a { font-size: 16px; color: #333; font-weight: 500; padding: 8px 0; }
.menu-overlay { display: none; position: fixed; top: 64px; left: 0; right: 0; bottom: 0; background: rgba(0,0,0,0.3); z-index: 98; }
.menu-overlay.active { display: block; }

@media (max-width: 768px) {
  .nav-links, .nav-cta { display: none; }
  .menu-toggle { display: block; }
  .article-layout { grid-template-columns: 1fr; }
  .sidebar { order: 2; }
  .article-title { font-size: 22px; }
  .article-cta { flex-direction: column; text-align: center; }
  .footer-grid { grid-template-columns: 1fr; }
}