:root {
  --bg0: #0b1c2c;
  --bg1: #12324a;
  --bg2: #1a4563;
  --sand: #e8f1f6;
  /* 正文 / 次要字：保证浅底上 ≥ WCAG AA */
  --ink: #0a1f2e;
  --muted: #243b4d;
  --accent: #0f6e60;
  --accent2: #c45f16;
  --line: rgba(15, 40, 55, 0.16);
  --card: #ffffff;
  --radius: 14px;
  --font-display: "Segoe UI", "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --font-body: "Segoe UI", "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --on-dark: #ffffff;
  --on-dark-soft: #e8f2f8;
  --on-dark-muted: #c5d8e6;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  color: var(--ink);
  /* 正文区固定浅底，避免深色标题落在渐变深蓝上 */
  background: #eef4f8;
  min-height: 100vh;
}

a { color: var(--accent); text-decoration: none; font-weight: 600; }
a:hover { text-decoration: underline; color: #0a574c; }

.wrap { width: min(1100px, 92vw); margin: 0 auto; }

.top {
  position: sticky; top: 0; z-index: 40;
  backdrop-filter: blur(10px);
  background: rgba(8, 22, 36, 0.94);
  border-bottom: 1px solid rgba(255,255,255,0.12);
}
.top-inner {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; padding: 0.75rem 0;
}
.brand-link {
  display: flex; align-items: center; gap: 0.65rem;
  color: var(--on-dark); font-weight: 700; text-decoration: none;
}
.brand-link img { width: 36px; height: 36px; border-radius: 8px; }
.brand-link span { font-size: 1.05rem; letter-spacing: 0.02em; }
.nav { display: flex; flex-wrap: wrap; align-items: center; gap: 0.75rem 1rem; }
.nav a { color: var(--on-dark-soft); font-size: 0.92rem; text-decoration: none; font-weight: 600; }
.nav a:hover { color: #fff; }
.nav .cta {
  background: var(--accent2); color: #fff !important;
  padding: 0.4rem 0.85rem; border-radius: 999px; font-weight: 700;
}

/* 顶栏语言框：浅底深字，展开列表系统白底也不会白字看不清 */
.lang-select {
  background: #f4f8fb;
  color: #0a1f2e;
  border: 1px solid rgba(255,255,255,0.55);
  border-radius: 8px;
  padding: 0.4rem 0.55rem;
  max-width: 12rem;
  font-weight: 650;
  font-size: 0.88rem;
  color-scheme: light;
}
.lang-select:focus {
  outline: 2px solid #3db8a6;
  outline-offset: 1px;
}
.lang-select option,
.lang-select optgroup {
  background: #ffffff;
  color: #0a1f2e;
}

.hero {
  padding: 4.5rem 0 3.25rem;
  color: var(--on-dark);
  background:
    radial-gradient(1000px 520px at 12% -20%, #2a6d8f 0%, transparent 55%),
    radial-gradient(800px 420px at 100% 0%, #1f8a7a44 0%, transparent 50%),
    linear-gradient(165deg, #07141f 0%, #0b1c2c 48%, #12324a 100%);
}
.hero-grid {
  display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 2rem; align-items: center;
}
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.7rem);
  line-height: 1.15; margin: 0 0 0.75rem; font-weight: 800;
  color: #fff;
  text-shadow: 0 1px 2px rgba(0,0,0,0.25);
}
.hero .tagline {
  font-size: 1.15rem; margin: 0 0 0.75rem; font-weight: 650;
  color: var(--on-dark-soft);
}
.hero .sub {
  margin: 0 0 1.5rem; line-height: 1.65; max-width: 36rem;
  color: var(--on-dark-muted);
}
.cta-row { display: flex; flex-wrap: wrap; gap: 0.75rem; margin-bottom: 0.75rem; }
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 0.75rem 1.2rem; border-radius: 10px; font-weight: 700;
  text-decoration: none; border: none; cursor: pointer;
}
.btn-primary { background: var(--accent2); color: #fff; }
.btn-secondary {
  /* 实色深底 + 白字，避免半透明落在亮区变成白底白字 */
  background: #0a3048;
  color: #fff;
  border: 1px solid #7eb8d4;
}
.btn:hover { filter: brightness(1.06); text-decoration: none; }
.hero-note {
  font-size: 0.95rem;
  color: #d7e8f2;
  font-weight: 600;
}
.hero-art {
  border-radius: 18px; overflow: hidden;
  box-shadow: 0 20px 50px rgba(0,0,0,0.35);
  border: 1px solid rgba(255,255,255,0.18);
  background: #0a1620;
}
.hero-art img { display: block; width: 100%; height: auto; }

main {
  background: #eef4f8;
  color: var(--ink);
}
.section { padding: 3rem 0; background: #eef4f8; }
.section h2 {
  font-size: 1.65rem; margin: 0 0 1.25rem; color: var(--ink); font-weight: 800;
}
.muted { color: var(--muted); }

.pillars {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 1rem;
}
.pillar {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.25rem 1.2rem;
  box-shadow: 0 1px 2px rgba(10, 30, 45, 0.04);
}
.pillar h3 { margin: 0 0 0.5rem; font-size: 1.1rem; color: var(--ink); }
.pillar p { margin: 0; color: var(--muted); line-height: 1.6; font-size: 0.96rem; }

.feature-block {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.5rem; margin-bottom: 1rem;
  box-shadow: 0 1px 2px rgba(10, 30, 45, 0.04);
}
.feature-block h3 { margin: 0 0 0.5rem; color: var(--ink); }
.feature-block p, .feature-block li { color: var(--muted); line-height: 1.65; }
.feature-block ul { margin: 0.5rem 0 0; padding-left: 1.2rem; }
.two-col { display: grid; grid-template-columns: 1fr 1fr; gap: 1rem; }
.shot {
  margin-top: 1rem; border-radius: 12px; overflow: hidden;
  border: 1px solid var(--line);
}
.shot img { width: 100%; display: block; }

.plans { display: grid; gap: 0.75rem; }
.plan-line {
  background: #fff; border-left: 4px solid var(--accent);
  padding: 0.85rem 1rem; border-radius: 0 10px 10px 0;
  border: 1px solid var(--line); border-left-width: 4px;
  color: var(--ink); line-height: 1.55;
}

.dl-grid {
  display: grid; grid-template-columns: 1fr 1fr; gap: 1rem;
}
.dl-card {
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 1.25rem;
}
.dl-card h3 { margin: 0 0 0.35rem; color: var(--ink); }
.dl-card .ver { font-size: 0.9rem; color: var(--muted); margin-bottom: 0.75rem; }
.dl-actions { display: flex; flex-wrap: wrap; gap: 0.5rem; }
.dl-actions a {
  background: var(--bg1); color: #fff; padding: 0.5rem 0.85rem;
  border-radius: 8px; font-size: 0.9rem; text-decoration: none; font-weight: 700;
}
.dl-actions a.ghost {
  background: #fff; color: var(--bg1); border: 1.5px solid #9eb4c4;
}
.dl-actions a.ghost:hover { border-color: var(--bg1); }

.faq details {
  background: #fff; border: 1px solid var(--line);
  border-radius: 10px; padding: 0.85rem 1rem; margin-bottom: 0.6rem;
}
.faq summary { cursor: pointer; font-weight: 700; color: var(--ink); }
.faq p { margin: 0.6rem 0 0; color: var(--muted); line-height: 1.6; }

.footer {
  margin-top: 2rem; padding: 2rem 0 3rem;
  background: #07141f; color: var(--on-dark-soft);
}
.footer h3 { color: #fff; text-align: center; font-size: 1rem; margin: 0 0 1rem; }
.lang-grid {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 0.5rem 0.65rem;
  margin-bottom: 1.5rem;
}
.lang-grid a {
  color: #eef6fb; background: rgba(255,255,255,0.1);
  border: 1px solid rgba(255,255,255,0.22);
  padding: 0.35rem 0.7rem; border-radius: 6px; font-size: 0.82rem;
  text-decoration: none; font-weight: 600;
}
.lang-grid a:hover { background: rgba(255,255,255,0.18); color: #fff; }
.lang-grid a.active {
  background: linear-gradient(135deg, #1a9a88, #0f6e60);
  color: #fff; border-color: transparent; font-weight: 700;
}
.footer-legal {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 0.65rem 1.1rem;
  margin-bottom: 1.5rem; font-size: 0.92rem;
}
.footer-legal a { color: #b8efe4; text-decoration: none; font-weight: 650; }
.footer-legal a:hover { color: #fff; text-decoration: underline; }
.footer-meta {
  text-align: center; font-size: 0.88rem; line-height: 1.75;
  color: var(--on-dark-muted);
}
.footer-meta a { color: #b8efe4; font-weight: 650; }
.footer-contact-line { margin-top: 0.4rem; color: var(--on-dark-soft); }

.legal-page { padding: 2rem 0 3rem; max-width: 760px; }
.legal-page h1 { font-size: 1.75rem; margin: 0 0 0.5rem; color: var(--ink); }
.legal-page h2 { font-size: 1.15rem; margin: 1.5rem 0 0.5rem; color: var(--ink); }
.legal-page p { color: var(--muted); line-height: 1.75; margin: 0.65rem 0; }
.legal-updated { font-size: 0.9rem; color: var(--muted); }
.legal-back { margin-bottom: 1rem; }
.legal-back a { color: var(--accent); text-decoration: none; font-weight: 700; }
.legal-back a:hover { text-decoration: underline; }
.contact-list { list-style: none; padding: 0; margin: 1rem 0; line-height: 1.9; color: var(--ink); }
.contact-list a { color: var(--accent); }

[dir="rtl"] .hero-grid { direction: rtl; }
[dir="rtl"] .nav { flex-direction: row-reverse; }

@media (max-width: 860px) {
  .hero-grid, .pillars, .two-col, .dl-grid { grid-template-columns: 1fr; }
  .hero { padding-top: 3rem; }
  .top-inner { flex-direction: column; align-items: flex-start; }
  .nav { width: 100%; }
}