/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
  color: #1a1a2e; background: #fff; line-height: 1.6; overflow-x: hidden;
}
a { text-decoration: none; color: inherit; transition: color .2s; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }

/* ===== Utility ===== */
.container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
.section { padding: 80px 0; }
.section-title { text-align: center; font-size: 2rem; font-weight: 700; margin-bottom: 16px; color: #1a1a2e; }
.section-subtitle { text-align: center; font-size: 1.1rem; color: #555; margin-bottom: 48px; max-width: 700px; margin-left: auto; margin-right: auto; }
.btn-primary {
  display: inline-block; padding: 14px 36px; background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #fff; border-radius: 50px; font-size: 1.1rem; font-weight: 600;
  transition: transform .2s, box-shadow .2s; border: none; cursor: pointer;
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 25px rgba(37,99,235,.35); color: #fff; }
.btn-outline {
  display: inline-block; padding: 12px 32px; border: 2px solid #2563eb; color: #2563eb;
  border-radius: 50px; font-size: 1rem; font-weight: 600; transition: all .2s;
}
.btn-outline:hover { background: #2563eb; color: #fff; }

/* ===== Navbar ===== */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 1000;
  background: rgba(255,255,255,.92); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(0,0,0,.06); height: 64px;
}
.navbar .container { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.nav-logo { font-size: 1.5rem; font-weight: 800; color: #2563eb; letter-spacing: -0.5px; }
.nav-logo span { color: #7c3aed; }
.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a { font-size: .95rem; color: #444; font-weight: 500; transition: color .2s; }
.nav-links a:hover { color: #2563eb; }
.nav-cta { padding: 8px 22px !important; background: linear-gradient(135deg, #2563eb, #7c3aed); color: #fff !important; border-radius: 50px; font-weight: 600; }
.nav-cta:hover { opacity: .9; color: #fff; }
.nav-toggle { display: none; flex-direction: column; gap: 5px; cursor: pointer; }
.nav-toggle span { width: 24px; height: 2px; background: #333; transition: .3s; }

/* ===== Hero ===== */
.hero {
  min-height: 100vh; display: flex; align-items: center; justify-content: center; text-align: center;
  background: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
  position: relative; overflow: hidden; padding-top: 64px;
}
.hero::before {
  content: ''; position: absolute; top: -50%; left: -50%; width: 200%; height: 200%;
  background: radial-gradient(circle at 30% 50%, rgba(37,99,235,.15) 0%, transparent 50%),
              radial-gradient(circle at 70% 50%, rgba(124,58,237,.15) 0%, transparent 50%);
  animation: heroGlow 8s ease-in-out infinite alternate;
}
@keyframes heroGlow { 0% { transform: translate(0,0); } 100% { transform: translate(-2%,2%); } }
.hero-content { position: relative; z-index: 2; max-width: 800px; padding: 0 20px; }
.hero h1 { font-size: 3.2rem; font-weight: 800; color: #fff; margin-bottom: 20px; line-height: 1.2; }
.hero h1 .highlight { background: linear-gradient(135deg, #60a5fa, #a78bfa); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero p { font-size: 1.25rem; color: rgba(255,255,255,.8); margin-bottom: 36px; line-height: 1.7; }
.hero-badge { display: inline-block; padding: 6px 18px; background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.2); border-radius: 50px; color: rgba(255,255,255,.9); font-size: .9rem; margin-bottom: 24px; }
.hero-buttons { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* ===== Stats ===== */
.stats { background: #f8fafc; padding: 60px 0; }
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px; }
.stat-item { text-align: center; }
.stat-number { font-size: 2.5rem; font-weight: 800; color: #2563eb; margin-bottom: 8px; }
.stat-label { font-size: .95rem; color: #666; }

/* ===== Features ===== */
.features { background: #fff; }
.features-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.feature-card {
  background: #fff; border: 1px solid #e5e7eb; border-radius: 16px; padding: 36px 28px;
  text-align: center; transition: transform .3s, box-shadow .3s;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 20px 40px rgba(0,0,0,.08); }
.feature-icon { font-size: 2.5rem; margin-bottom: 20px; }
.feature-card h3 { font-size: 1.2rem; font-weight: 700; margin-bottom: 12px; color: #1a1a2e; }
.feature-card p { font-size: .95rem; color: #666; line-height: 1.6; }

/* ===== Nodes ===== */
.nodes { background: #f8fafc; }
.nodes-grid { display: flex; flex-wrap: wrap; justify-content: center; gap: 16px; }
.node-tag {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 24px; background: #fff; border: 1px solid #e5e7eb;
  border-radius: 50px; font-size: .95rem; font-weight: 500; color: #333;
  transition: all .2s;
}
.node-tag:hover { border-color: #2563eb; color: #2563eb; box-shadow: 0 4px 12px rgba(37,99,235,.1); }
.node-flag { font-size: 1.3rem; }

/* ===== Platforms ===== */
.platforms { background: #fff; }
.platforms-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }
.platform-card {
  text-align: center; padding: 40px 24px; background: #f8fafc;
  border-radius: 16px; border: 1px solid #e5e7eb; transition: all .3s;
}
.platform-card:hover { border-color: #2563eb; box-shadow: 0 8px 24px rgba(37,99,235,.1); }
.platform-icon { font-size: 3rem; margin-bottom: 16px; }
.platform-card h3 { font-size: 1.1rem; font-weight: 700; margin-bottom: 16px; }
.platform-card .btn-outline { font-size: .9rem; padding: 8px 24px; }

/* ===== Pricing ===== */
.pricing { background: #f8fafc; }
.pricing-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 28px; max-width: 900px; margin: 0 auto; }
.pricing-card {
  background: #fff; border: 2px solid #e5e7eb; border-radius: 20px; padding: 40px 32px;
  text-align: center; transition: all .3s; position: relative;
}
.pricing-card.featured { border-color: #2563eb; transform: scale(1.03); }
.pricing-badge {
  position: absolute; top: -14px; left: 50%; transform: translateX(-50%);
  padding: 4px 20px; background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #fff; border-radius: 50px; font-size: .85rem; font-weight: 600;
}
.pricing-card h3 { font-size: 1.3rem; font-weight: 700; margin-bottom: 8px; }
.pricing-card .price { font-size: 2.5rem; font-weight: 800; color: #2563eb; margin: 16px 0; }
.pricing-card .price span { font-size: 1rem; color: #999; font-weight: 400; }
.pricing-card .price-period { color: #999; font-size: .9rem; margin-bottom: 24px; }
.pricing-features { text-align: left; margin-bottom: 32px; }
.pricing-features li { padding: 8px 0; color: #555; font-size: .95rem; display: flex; align-items: center; gap: 8px; }
.pricing-features li::before { content: '\2713'; color: #2563eb; font-weight: 700; }
.pricing-table { width: 100%; max-width: 900px; margin: 40px auto 0; border-collapse: collapse; }
.pricing-table th, .pricing-table td { padding: 14px 20px; text-align: center; border-bottom: 1px solid #e5e7eb; }
.pricing-table th { background: #f1f5f9; font-weight: 600; color: #333; }
.pricing-table td { color: #555; }

/* ===== Testimonials ===== */
.testimonials { background: #fff; }
.testimonials-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 28px; }
.testimonial-card {
  background: #f8fafc; border-radius: 16px; padding: 32px; border: 1px solid #e5e7eb;
}
.testimonial-stars { color: #f59e0b; font-size: 1.1rem; margin-bottom: 16px; }
.testimonial-text { font-size: .95rem; color: #555; line-height: 1.7; margin-bottom: 20px; font-style: italic; }
.testimonial-author { display: flex; align-items: center; gap: 12px; }
.testimonial-avatar {
  width: 40px; height: 40px; border-radius: 50%; background: linear-gradient(135deg, #2563eb, #7c3aed);
  display: flex; align-items: center; justify-content: center; color: #fff; font-weight: 700; font-size: .9rem;
}
.testimonial-name { font-weight: 600; font-size: .9rem; }
.testimonial-role { font-size: .8rem; color: #999; }
.trust-badges { display: flex; justify-content: center; gap: 40px; margin-top: 48px; flex-wrap: wrap; }
.trust-badge { text-align: center; color: #666; font-size: .9rem; }
.trust-badge-icon { font-size: 2rem; margin-bottom: 8px; }

/* ===== FAQ ===== */
.faq { background: #f8fafc; }
.faq-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; max-width: 1000px; margin: 0 auto; }
.faq-item {
  background: #fff; border: 1px solid #e5e7eb; border-radius: 12px; padding: 28px;
}
.faq-item h3 { font-size: 1.05rem; font-weight: 700; color: #1a1a2e; margin-bottom: 16px; display: flex; align-items: flex-start; gap: 10px; }
.faq-item h3 .faq-num {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 28px; height: 28px; background: linear-gradient(135deg, #2563eb, #7c3aed);
  color: #fff; border-radius: 50%; font-size: .8rem; font-weight: 700; flex-shrink: 0;
}
.faq-steps { padding-left: 0; }
.faq-steps li {
  padding: 6px 0; font-size: .93rem; color: #555; line-height: 1.7;
  display: flex; gap: 10px; align-items: flex-start;
}
.faq-steps li .step-label {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 22px; height: 22px; background: #eff6ff; color: #2563eb;
  border-radius: 50%; font-size: .75rem; font-weight: 700; flex-shrink: 0; margin-top: 2px;
}

/* ===== Footer ===== */
.footer {
  background: #0f0c29; color: rgba(255,255,255,.7); padding: 60px 0 0;
}
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1fr 1.5fr; gap: 40px; margin-bottom: 40px; }
.footer-brand .nav-logo { margin-bottom: 16px; display: inline-block; }
.footer-brand p { font-size: .9rem; line-height: 1.7; color: rgba(255,255,255,.5); }
.footer h4 { color: #fff; font-size: 1rem; font-weight: 600; margin-bottom: 20px; }
.footer ul li { margin-bottom: 10px; }
.footer ul li a { color: rgba(255,255,255,.6); font-size: .9rem; transition: color .2s; }
.footer ul li a:hover { color: #60a5fa; }
.footer-contact p { font-size: .9rem; margin-bottom: 8px; }
.footer-warning {
  background: rgba(245,158,11,.1); border: 1px solid rgba(245,158,11,.3);
  border-radius: 8px; padding: 16px 20px; margin-bottom: 32px;
  color: #f59e0b; font-size: .9rem; text-align: center;
}
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,.1); padding: 20px 0;
  text-align: center; font-size: .85rem; color: rgba(255,255,255,.4);
}

/* ===== Sub-page Hero ===== */
.page-hero {
  padding: 140px 0 60px; text-align: center;
  background: linear-gradient(135deg, #0f0c29 0%, #302b63 50%, #24243e 100%);
}
.page-hero h1 { font-size: 2.5rem; font-weight: 800; color: #fff; margin-bottom: 16px; }
.page-hero p { font-size: 1.15rem; color: rgba(255,255,255,.7); max-width: 600px; margin: 0 auto; }

/* ===== Help Page ===== */
.help-category {
  background: #fff; border: 1px solid #e5e7eb; border-radius: 16px; padding: 36px; margin-bottom: 28px;
}
.help-category h2 { font-size: 1.4rem; font-weight: 700; color: #1a1a2e; margin-bottom: 24px; display: flex; align-items: center; gap: 12px; }
.help-category h2 .cat-icon { font-size: 1.6rem; }
.help-qa { margin-bottom: 28px; padding-bottom: 28px; border-bottom: 1px solid #f1f5f9; }
.help-qa:last-child { margin-bottom: 0; padding-bottom: 0; border-bottom: none; }
.help-qa h3 { font-size: 1.05rem; font-weight: 600; color: #2563eb; margin-bottom: 14px; }

/* ===== Privacy Page ===== */
.privacy-content { max-width: 800px; margin: 0 auto; }
.privacy-content h2 { font-size: 1.4rem; font-weight: 700; margin: 32px 0 16px; color: #1a1a2e; }
.privacy-content p { font-size: .95rem; color: #555; line-height: 1.8; margin-bottom: 16px; }
.privacy-content ul { padding-left: 20px; margin-bottom: 16px; }
.privacy-content ul li { font-size: .95rem; color: #555; line-height: 1.8; margin-bottom: 6px; position: relative; padding-left: 16px; }
.privacy-content ul li::before { content: '\2022'; color: #2563eb; position: absolute; left: 0; }

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .features-grid, .platforms-grid { grid-template-columns: repeat(2, 1fr); }
  .stats-grid { grid-template-columns: repeat(2, 1fr); gap: 24px; }
  .testimonials-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 768px) {
  .nav-links { display: none; }
  .nav-toggle { display: flex; }
  .hero h1 { font-size: 2rem; }
  .hero p { font-size: 1rem; }
  .section { padding: 50px 0; }
  .section-title { font-size: 1.6rem; }
  .features-grid, .platforms-grid, .pricing-grid, .faq-grid { grid-template-columns: 1fr; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-card.featured { transform: none; }
  .footer-grid { grid-template-columns: 1fr; }
  .page-hero h1 { font-size: 1.8rem; }
  .hero-buttons { flex-direction: column; align-items: center; }
}