:root {
  --primary: #2563eb;
  --primary-2: #0ea5e9;
  --accent: #14b8a6;
  --dark: #0f172a;
  --text: #334155;
  --muted: #64748b;
  --line: #e2e8f0;
  --bg: #f8fafc;
  --card: #ffffff;
  --grad: linear-gradient(135deg, #2563eb 0%, #0ea5e9 55%, #14b8a6 100%);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
img { max-width: 100%; display: block; }

.container { width: 100%; max-width: 1200px; margin: 0 auto; padding: 0 24px; }

/* Header */
.header {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 68px; }
.brand { display: flex; align-items: center; gap: 12px; font-weight: 700; font-size: 22px; color: var(--dark); }
.brand img { width: 36px; height: 36px; border-radius: 9px; }
.brand span em { font-style: normal; color: var(--primary); }
.nav { display: flex; align-items: center; gap: 6px; }
.nav a {
  padding: 8px 16px; border-radius: 10px; font-size: 15px; font-weight: 500; color: var(--text);
  transition: all .2s ease;
}
.nav a:hover, .nav a.active { color: var(--primary); background: rgba(37, 99, 235, 0.08); }
.nav .nav-download {
  margin-left: 10px; padding: 10px 20px; color: #fff; background: var(--grad);
  border-radius: 10px; font-weight: 600; box-shadow: 0 8px 20px rgba(37, 99, 235, 0.28);
}
.nav .nav-download:hover { color: #fff; transform: translateY(-2px); box-shadow: 0 12px 26px rgba(37, 99, 235, 0.34); }
.nav-toggle { display: none; background: none; border: 0; font-size: 26px; color: var(--dark); cursor: pointer; }

/* Hero */
.hero {
  position: relative; overflow: hidden;
  background: var(--grad);
  color: #fff; padding: 88px 0 96px;
}
.hero::before {
  content: ""; position: absolute; inset: 0;
  background: radial-gradient(circle at 85% 20%, rgba(255,255,255,0.18), transparent 45%),
              radial-gradient(circle at 10% 90%, rgba(255,255,255,0.10), transparent 40%);
}
.hero-inner { position: relative; display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.hero-badge {
  display: inline-flex; align-items: center; gap: 8px; padding: 7px 16px; border-radius: 999px;
  background: rgba(255,255,255,0.16); border: 1px solid rgba(255,255,255,0.25); font-size: 13px; font-weight: 500;
}
.hero h1 { font-size: 46px; line-height: 1.2; margin: 22px 0 18px; font-weight: 800; letter-spacing: -0.5px; }
.hero h1 .hl { background: linear-gradient(90deg, #fef08a, #fde047); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero-desc { font-size: 18px; color: rgba(255,255,255,0.92); max-width: 520px; }
.hero-actions { display: flex; align-items: center; gap: 16px; margin-top: 32px; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 14px 30px; border-radius: 12px; font-size: 16px; font-weight: 600; cursor: pointer;
  transition: all .2s ease; border: 0;
}
.btn-primary { background: #fff; color: var(--primary); box-shadow: 0 12px 30px rgba(0,0,0,0.18); }
.btn-primary:hover { transform: translateY(-3px); box-shadow: 0 16px 36px rgba(0,0,0,0.24); }
.btn-ghost { background: rgba(255,255,255,0.14); color: #fff; border: 1px solid rgba(255,255,255,0.35); }
.btn-ghost:hover { background: rgba(255,255,255,0.24); }
.hero-stats { display: flex; gap: 40px; margin-top: 40px; flex-wrap: wrap; }
.hero-stats .stat b { display: block; font-size: 30px; font-weight: 800; }
.hero-stats .stat span { font-size: 14px; color: rgba(255,255,255,0.85); }

/* Simulator */
.simulator {
  background: #fff; border-radius: 20px; box-shadow: 0 30px 70px rgba(2, 6, 23, 0.35);
  overflow: hidden; color: var(--text); transform: rotate(0deg);
}
.sim-head { display: flex; align-items: center; gap: 8px; padding: 14px 18px; background: #f1f5f9; border-bottom: 1px solid var(--line); }
.sim-dot { width: 12px; height: 12px; border-radius: 50%; }
.sim-dot.r { background: #f87171; } .sim-dot.y { background: #fbbf24; } .sim-dot.g { background: #34d399; }
.sim-title { margin-left: 8px; font-size: 13px; font-weight: 600; color: var(--muted); }
.sim-body { padding: 20px; }
.lang-row { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.lang-select {
  flex: 1; padding: 10px 12px; border: 1px solid var(--line); border-radius: 10px;
  font-size: 14px; background: #fff; cursor: pointer; color: var(--dark); font-weight: 500;
}
.lang-swap {
  width: 40px; height: 40px; border-radius: 10px; border: 1px solid var(--line);
  background: #fff; cursor: pointer; font-size: 16px; color: var(--primary);
  transition: all .2s ease; display: flex; align-items: center; justify-content: center;
}
.lang-swap:hover { background: rgba(37,99,235,0.08); transform: rotate(180deg); }
.sim-textarea {
  width: 100%; min-height: 110px; resize: vertical; padding: 14px; border-radius: 12px;
  border: 1px solid var(--line); font-size: 15px; font-family: inherit; color: var(--dark); background: #fbfdff;
}
.sim-textarea:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(37,99,235,0.12); }
.sim-toolbar { display: flex; align-items: center; justify-content: space-between; margin: 10px 0 16px; }
.sim-count { font-size: 12px; color: var(--muted); }
.sim-actions { display: flex; gap: 8px; }
.icon-btn {
  width: 32px; height: 32px; border-radius: 8px; border: 1px solid var(--line); background: #fff;
  cursor: pointer; font-size: 14px; color: var(--muted); transition: all .2s ease;
}
.icon-btn:hover { color: var(--primary); border-color: var(--primary); }
.btn-translate {
  width: 100%; padding: 13px; border: 0; border-radius: 12px; background: var(--grad);
  color: #fff; font-size: 16px; font-weight: 700; cursor: pointer; transition: all .2s ease;
  box-shadow: 0 10px 24px rgba(37,99,235,0.3);
}
.btn-translate:hover { transform: translateY(-2px); box-shadow: 0 14px 30px rgba(37,99,235,0.38); }
.sim-output {
  margin-top: 16px; padding: 16px; border-radius: 12px; background: #f0fdf4; border: 1px solid #bbf7d0;
  min-height: 92px; font-size: 15px; color: #14532d; white-space: pre-wrap;
}
.sim-output .loading { color: var(--muted); font-style: italic; }

/* Sections */
.section { padding: 84px 0; }
.section-alt { background: #fff; }
.section-head { text-align: center; max-width: 680px; margin: 0 auto 52px; }
.section-tag {
  display: inline-block; padding: 6px 16px; border-radius: 999px; background: rgba(37,99,235,0.08);
  color: var(--primary); font-size: 13px; font-weight: 600; margin-bottom: 16px;
}
.section-head h2 { font-size: 36px; color: var(--dark); font-weight: 800; letter-spacing: -0.5px; }
.section-head p { margin-top: 14px; font-size: 16px; color: var(--muted); }

/* Feature grid */
.feature-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 30px 26px;
  transition: all .25s ease; position: relative; overflow: hidden;
}
.feature-card:hover { transform: translateY(-6px); box-shadow: 0 20px 40px rgba(15,23,42,0.08); border-color: rgba(37,99,235,0.25); }
.feature-icon {
  width: 56px; height: 56px; border-radius: 14px; display: flex; align-items: center; justify-content: center;
  font-size: 26px; background: linear-gradient(135deg, rgba(37,99,235,0.1), rgba(20,184,166,0.1)); margin-bottom: 18px;
}
.feature-card h3 { font-size: 20px; color: var(--dark); font-weight: 700; margin-bottom: 10px; }
.feature-card p { font-size: 15px; color: var(--muted); }

/* Download cards */
.dl-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 22px; }
.dl-card {
  background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 32px 24px; text-align: center;
  transition: all .25s ease;
}
.dl-card:hover { transform: translateY(-6px); box-shadow: 0 20px 40px rgba(15,23,42,0.1); }
.dl-card .dl-icon { font-size: 40px; margin-bottom: 16px; }
.dl-card h3 { font-size: 20px; color: var(--dark); margin-bottom: 8px; }
.dl-card .ver { font-size: 13px; color: var(--muted); margin-bottom: 18px; }
.dl-card .btn-download {
  display: inline-block; padding: 12px 26px; border-radius: 10px; background: var(--grad); color: #fff;
  font-weight: 600; font-size: 15px; transition: all .2s ease; box-shadow: 0 8px 18px rgba(37,99,235,0.25);
}
.dl-card .btn-download:hover { transform: translateY(-2px); box-shadow: 0 12px 24px rgba(37,99,235,0.34); }

/* News */
.news-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 20px; }
.news-item {
  display: flex; gap: 18px; background: var(--card); border: 1px solid var(--line); border-radius: 14px;
  padding: 22px; transition: all .2s ease;
}
.news-item:hover { border-color: rgba(37,99,235,0.3); box-shadow: 0 12px 28px rgba(15,23,42,0.07); }
.news-date {
  flex: 0 0 64px; height: 64px; border-radius: 12px; background: rgba(37,99,235,0.08); color: var(--primary);
  display: flex; flex-direction: column; align-items: center; justify-content: center; font-weight: 700;
}
.news-date b { font-size: 24px; line-height: 1; }
.news-date span { font-size: 12px; }
.news-item h4 { font-size: 17px; color: var(--dark); margin-bottom: 6px; }
.news-item p { font-size: 14px; color: var(--muted); }

/* FAQ */
.faq-list { max-width: 860px; margin: 0 auto; }
.faq-item {
  background: var(--card); border: 1px solid var(--line); border-radius: 14px; margin-bottom: 16px; overflow: hidden;
}
.faq-q {
  display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 20px 24px;
  cursor: pointer; font-size: 17px; font-weight: 600; color: var(--dark);
}
.faq-q .faq-arrow { font-size: 18px; color: var(--muted); transition: transform .2s ease; flex: 0 0 auto; }
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-a { display: none; padding: 0 24px 22px; color: var(--text); font-size: 15px; }
.faq-item.open .faq-a { display: block; }
.faq-a ol { list-style: decimal; padding-left: 20px; margin-top: 8px; }
.faq-a ol li { margin-bottom: 8px; }

/* About */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: center; }
.about-text h3 { font-size: 26px; color: var(--dark); margin-bottom: 18px; font-weight: 700; }
.about-text p { margin-bottom: 14px; color: var(--text); }
.about-values { display: grid; grid-template-columns: repeat(2, 1fr); gap: 14px; margin-top: 24px; }
.value-item { display: flex; align-items: center; gap: 10px; font-size: 15px; font-weight: 500; color: var(--dark); }
.value-item .vi { color: var(--primary); font-size: 18px; }
.about-visual {
  border-radius: 20px; overflow: hidden; background: var(--grad); padding: 48px 40px; color: #fff;
}
.about-visual b { display: block; font-size: 52px; font-weight: 800; margin-bottom: 8px; }
.about-visual p { color: rgba(255,255,255,0.9); }

/* Page hero (inner pages) */
.page-hero { background: var(--grad); color: #fff; padding: 64px 0; position: relative; overflow: hidden; }
.page-hero::before { content: ""; position: absolute; inset: 0; background: radial-gradient(circle at 80% 20%, rgba(255,255,255,0.16), transparent 45%); }
.page-hero .container { position: relative; }
.page-hero h1 { font-size: 38px; font-weight: 800; }
.page-hero p { margin-top: 12px; font-size: 17px; color: rgba(255,255,255,0.92); max-width: 640px; }

/* Breadcrumb */
.crumb { padding: 18px 0; font-size: 14px; color: var(--muted); }
.crumb a:hover { color: var(--primary); }

/* Footer */
.footer { background: var(--dark); color: #cbd5e1; padding: 60px 0 0; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr 1fr; gap: 40px; padding-bottom: 40px; }
.footer-brand p { margin-top: 14px; font-size: 14px; color: #94a3b8; max-width: 300px; }
.footer-col h4 { color: #fff; font-size: 16px; font-weight: 700; margin-bottom: 18px; }
.footer-col a { display: block; margin-bottom: 12px; font-size: 14px; color: #94a3b8; transition: color .2s ease; }
.footer-col a:hover { color: #fff; }
.footer-links { padding: 24px 0; border-top: 1px solid rgba(255,255,255,0.08); }
.friend-links { text-align: center; }
.friend-links h4 { color: #fff; font-size: 15px; margin-bottom: 14px; }
#my-friend-links { display: flex; flex-wrap: wrap; gap: 12px; justify-content: center; }
#my-friend-links a { color: #94a3b8; font-size: 14px; padding: 6px 14px; border: 1px solid rgba(255,255,255,0.12); border-radius: 999px; transition: all .2s ease; }
#my-friend-links a:hover { color: #fff; border-color: rgba(255,255,255,0.35); }
.footer-bottom { text-align: center; padding: 22px 0; border-top: 1px solid rgba(255,255,255,0.08); font-size: 13px; color: #64748b; }
.footer-bottom a { color: #94a3b8; }
.footer-bottom a:hover { color: #fff; }

/* Sitemap page */
.sitemap-group { margin-bottom: 40px; }
.sitemap-group h3 { font-size: 22px; color: var(--dark); margin-bottom: 16px; font-weight: 700; border-left: 4px solid var(--primary); padding-left: 14px; }
.sitemap-group ul li { margin-bottom: 10px; }
.sitemap-group ul li a { color: var(--text); font-size: 16px; transition: color .2s ease; }
.sitemap-group ul li a:hover { color: var(--primary); }

/* Responsive */
@media (max-width: 992px) {
  .hero-inner { grid-template-columns: 1fr; }
  .hero h1 { font-size: 36px; }
  .feature-grid { grid-template-columns: repeat(2, 1fr); }
  .dl-grid { grid-template-columns: repeat(2, 1fr); }
  .news-list { grid-template-columns: 1fr; }
  .about-grid { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 640px) {
  .nav { display: none; position: absolute; top: 68px; left: 0; right: 0; background: #fff; flex-direction: column; padding: 12px; border-bottom: 1px solid var(--line); box-shadow: 0 20px 30px rgba(0,0,0,0.08); }
  .nav.open { display: flex; }
  .nav-toggle { display: block; }
  .feature-grid { grid-template-columns: 1fr; }
  .dl-grid { grid-template-columns: 1fr; }
  .hero { padding: 60px 0 70px; }
  .hero-stats { gap: 24px; }
  .footer-grid { grid-template-columns: 1fr; }
  .about-values { grid-template-columns: 1fr; }
}