/* 小白沚鹿官网 — 共用样式
   深蓝主题 #16213e / 青色强调 #00d4ff
   纯静态、零依赖、响应式 */

:root {
  --bg: #16213e;
  --bg-2: #1b2a4a;
  --bg-3: #0f1830;
  --accent: #00d4ff;
  --accent-soft: rgba(0, 212, 255, 0.15);
  --text: #e8eef7;
  --text-dim: #9fb0c8;
  --border: rgba(0, 212, 255, 0.22);
  --radius: 14px;
  --maxw: 1080px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

img { max-width: 100%; }

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }

/* ---------- 顶部导航 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(15, 24, 48, 0.85);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  height: 64px;
}
.brand {
  font-weight: 800;
  font-size: 1.15rem;
  letter-spacing: 0.5px;
  color: var(--text);
  white-space: nowrap;
}
.brand span { color: var(--accent); }
.nav-links { display: flex; gap: 18px; flex-wrap: wrap; }
.nav-links a { color: var(--text-dim); font-size: 0.95rem; }
.nav-links a:hover, .nav-links a.active { color: var(--accent); text-decoration: none; }

/* ---------- 通用区块 ---------- */
main { display: block; }
section { padding: 56px 0; border-bottom: 1px solid rgba(255,255,255,0.05); }
section:last-of-type { border-bottom: none; }
.section-title {
  font-size: 1.6rem;
  margin: 0 0 8px;
  color: var(--text);
}
.section-sub { color: var(--text-dim); margin: 0 0 28px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-block;
  padding: 12px 26px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 1rem;
  cursor: pointer;
  border: 1px solid var(--accent);
  transition: transform 0.12s ease, box-shadow 0.12s ease;
}
.btn:hover { text-decoration: none; transform: translateY(-1px); }
.btn-primary {
  background: var(--accent);
  color: #06243a;
  box-shadow: 0 6px 22px rgba(0, 212, 255, 0.35);
}
.btn-ghost {
  background: transparent;
  color: var(--accent);
}
.btn-block { display: block; text-align: center; }

/* ---------- Hero ---------- */
.hero {
  text-align: center;
  padding: 88px 0 72px;
  background:
    radial-gradient(900px 420px at 50% -10%, rgba(0,212,255,0.18), transparent 60%),
    var(--bg);
}
.hero h1 {
  font-size: clamp(1.9rem, 5vw, 3rem);
  line-height: 1.2;
  margin: 0 0 18px;
}
.hero h1 .hl { color: var(--accent); }
.hero p.sub {
  font-size: 1.15rem;
  color: var(--text-dim);
  max-width: 720px;
  margin: 0 auto 32px;
}
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

/* ---------- 卡片网格 ---------- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
}
.card {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card .ico { font-size: 1.8rem; }
.card h3 { margin: 10px 0 6px; font-size: 1.2rem; }
.card p { color: var(--text-dim); margin: 0 0 14px; }

/* ---------- 价格表 ---------- */
.price-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px; }
.price {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 22px;
  display: flex;
  flex-direction: column;
}
.price.recommend { border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.price .tag {
  align-self: flex-start;
  font-size: 0.75rem;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 3px 10px;
  border-radius: 999px;
  margin-bottom: 10px;
}
.price h3 { margin: 0 0 4px; font-size: 1.15rem; }
.price .amount { font-size: 1.9rem; font-weight: 800; color: var(--accent); }
.price .amount small { font-size: 0.9rem; color: var(--text-dim); font-weight: 400; }
.price ul { list-style: none; padding: 0; margin: 14px 0 18px; color: var(--text-dim); flex: 1; }
.price ul li { padding: 4px 0 4px 20px; position: relative; }
.price ul li::before { content: "✓"; color: var(--accent); position: absolute; left: 0; }
.price .note { font-size: 0.82rem; color: var(--text-dim); margin-top: 6px; }

/* ---------- 下载区 ---------- */
.download-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 18px; }
.dl-card { background: var(--bg-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; }
.dl-card h3 { margin: 0 0 6px; }
.dl-card .meta { color: var(--text-dim); font-size: 0.9rem; margin-bottom: 16px; }
.badge {
  display: inline-block; font-size: 0.78rem; padding: 3px 10px;
  border-radius: 999px; margin-left: 8px;
}
.badge-ok { background: var(--accent-soft); color: var(--accent); }
.badge-soon { background: rgba(255,255,255,0.08); color: var(--text-dim); }

/* ---------- 步骤 ---------- */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 18px; }
.step { background: var(--bg-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; }
.step .num {
  width: 38px; height: 38px; border-radius: 50%;
  display: grid; place-items: center;
  background: var(--accent-soft); color: var(--accent); font-weight: 800; margin-bottom: 12px;
}

/* ---------- 许可旅程 ---------- */
.flow { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 14px; }
.flow .node { background: var(--bg-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 18px; text-align: center; }
.flow .node b { color: var(--accent); }

/* ---------- FAQ ---------- */
details {
  background: var(--bg-2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 4px 18px;
  margin-bottom: 12px;
}
details summary {
  cursor: pointer;
  font-weight: 700;
  padding: 14px 0;
  list-style: none;
}
details summary::-webkit-details-marker { display: none; }
details summary::before { content: "▸ "; color: var(--accent); }
details[open] summary::before { content: "▾ "; }
details .answer { color: var(--text-dim); padding: 0 0 14px; }

/* ---------- 文章列表 ---------- */
.article-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 18px; }
.article-card { background: var(--bg-2); border: 1px solid var(--border); border-radius: var(--radius); padding: 22px; display: flex; flex-direction: column; }
.article-card h3 { margin: 0 0 8px; font-size: 1.1rem; }
.article-card p { color: var(--text-dim); flex: 1; margin: 0 0 12px; }
.article-card .date { font-size: 0.8rem; color: var(--text-dim); }

/* ---------- 页脚 ---------- */
.site-footer { background: var(--bg-3); padding: 36px 0; color: var(--text-dim); font-size: 0.9rem; }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; align-items: center; }
.site-footer a { color: var(--text-dim); }

/* ---------- 响应式 ---------- */
@media (max-width: 640px) {
  .nav { height: auto; padding: 10px 0; gap: 8px; }
  .nav-links { gap: 12px; }
  section { padding: 40px 0; }
  .hero { padding: 64px 0 52px; }
}

/* ── 导航下拉：桌面 hover 展开，移动端点击展开（JS 切 .open）── */
.brand em { font-style: normal; font-weight: 400; font-size: 12px; color: var(--text-dim); margin-left: 8px; }
.nav-item { position: relative; }
.nav-item > a { cursor: default; }
.dropdown-menu {
  display: none; position: absolute; top: 100%; left: -8px; z-index: 60;
  background: var(--bg-2); border: 1px solid var(--border); border-radius: 10px;
  padding: 6px 0; min-width: 200px; box-shadow: 0 10px 30px rgba(0,0,0,.4);
}
@media (min-width: 821px) {
  .nav-item:hover .dropdown-menu,
  .nav-item:focus-within .dropdown-menu { display: block; }
}
.dropdown-menu a { display: block; padding: 8px 16px; white-space: nowrap; font-size: .92rem; color: var(--text-dim); }
.dropdown-menu a:hover { background: var(--accent-soft); color: var(--accent); text-decoration: none; }
@media (max-width: 820px) {
  .dropdown-menu { position: static; box-shadow: none; border: 0; background: transparent; padding: 0 0 0 14px; min-width: 0; }
  .nav-item.open .dropdown-menu { display: block; }
  .nav-item > a { cursor: pointer; }
  .brand em { display: none; }
}