/* ============================================================
   号码盾 · 深色科技风 · 公共样式（全站共享）
   来源：sms2/index.html 的 :root / reset / nav / footer / 通用组件
   页面私有样式（hero/demo/app/coverage 等）在各页 {block page_styles}
   ============================================================ */

/* ===== 设计 Token ===== */
:root {
  /* 中性层 — 深色科技底 */
  --bg:        oklch(15% 0.02 250);
  --surface:   oklch(19% 0.022 250);
  --surface-2: oklch(23% 0.024 250);
  --fg:        oklch(96% 0.005 250);
  --muted:     oklch(62% 0.015 250);
  --border:    oklch(30% 0.018 250);

  /* 强调色 — 单一电光青 */
  --accent:     oklch(78% 0.15 195);
  --accent-dim: oklch(78% 0.15 195 / 0.14);

  /* 语义色 */
  --success: oklch(72% 0.15 150);
  --warn:    oklch(75% 0.15 70);
  --danger:  oklch(65% 0.18 25);

  /* 正文层级色（长文用） */
  --fg-strong: oklch(88% 0.005 250);
  --fg-body:   oklch(84% 0.005 250);

  --font-display: -apple-system, BlinkMacSystemFont, 'SF Pro Display', system-ui, sans-serif;
  --font-body:    -apple-system, BlinkMacSystemFont, 'SF Pro Text', system-ui, sans-serif;
  --font-mono:    ui-monospace, 'SF Mono', 'JetBrains Mono', Menlo, monospace;
}

/* ===== Reset & Base ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 var(--font-body);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
img { max-width: 100%; height: auto; }
::selection { background: var(--accent); color: var(--bg); }

/* ===== 容器 ===== */
.wrap { max-width: 1180px; margin: 0 auto; padding: 0 28px; }

/* ===== NAV ===== */
nav {
  position: sticky; top: 0; z-index: 100;
  background: color-mix(in oklch, var(--bg) 82%, transparent);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  height: 64px;
}
.logo {
  display: flex; align-items: center; gap: 9px;
  font-weight: 600; font-size: 17px; letter-spacing: -0.01em;
  color: var(--fg);
}
.logo-mark {
  width: 26px; height: 26px; border-radius: 7px;
  background: var(--accent);
  display: grid; place-items: center;
  color: var(--bg);
}
.logo-mark svg { width: 15px; height: 15px; }
.nav-links { display: flex; gap: 30px; align-items: center; }
.nav-links a {
  color: var(--muted); font-size: 14px; transition: color .15s;
  letter-spacing: 0.01em;
}
.nav-links a:hover, .nav-links a.active { color: var(--fg); }

/* 产品下拉菜单 */
.has-dropdown { position: relative; }
.nav-trigger {
  display: inline-flex; align-items: center; gap: 5px;
  color: var(--muted); font-size: 14px; cursor: pointer;
  background: none; border: 0; font-family: var(--font-body); padding: 0;
}
.nav-trigger:hover, .has-dropdown:hover .nav-trigger { color: var(--fg); }
.nav-trigger .caret { width: 12px; height: 12px; transition: transform .2s; }
.has-dropdown:hover .nav-trigger .caret { transform: rotate(180deg); }
.dropdown {
  position: absolute; top: calc(100% + 10px); left: 50%;
  transform: translateX(-50%) translateY(6px);
  min-width: 220px; background: var(--surface);
  border: 1px solid var(--border); border-radius: 12px; padding: 8px;
  box-shadow: 0 20px 50px -12px rgba(0,0,0,.6);
  opacity: 0; visibility: hidden;
  transition: opacity .15s, transform .15s, visibility .15s; z-index: 200;
}
.has-dropdown:hover .dropdown {
  opacity: 1; visibility: visible; transform: translateX(-50%) translateY(0);
}
.dropdown a {
  display: flex; align-items: center; gap: 11px; padding: 10px 12px;
  border-radius: 8px; color: var(--fg); font-size: 14px; transition: background .12s;
}
.dropdown a:hover { background: color-mix(in oklch, var(--fg) 8%, transparent); color: var(--fg); }
.dropdown a .d-ico {
  width: 28px; height: 28px; border-radius: 7px; display: grid; place-items: center;
  color: #fff; flex-shrink: 0; font: 700 13px/1 var(--font-display);
}
.dropdown a .d-txt strong { display: block; font-weight: 550; font-size: 14px; }
.dropdown a .d-txt span { display: block; font-size: 12px; color: var(--muted); }
.dropdown-head {
  font: 600 10px/1 var(--font-mono); letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted); padding: 8px 12px 6px;
}
.dropdown-sep { height: 1px; background: var(--border); margin: 4px 0; }

/* ===== 按钮 ===== */
.btn {
  display: inline-flex; align-items: center; gap: 7px;
  padding: 9px 16px; border-radius: 8px;
  font-size: 14px; font-weight: 550; letter-spacing: 0.01em;
  border: 1px solid transparent; cursor: pointer;
  transition: all .15s; font-family: var(--font-body);
}
.btn-primary { background: var(--accent); color: var(--bg); }
.btn-primary:hover { filter: brightness(1.08); transform: translateY(-1px); }
.btn-ghost { background: transparent; color: var(--fg); border-color: var(--border); }
.btn-ghost:hover { border-color: var(--muted); }
.btn-lg { padding: 13px 22px; font-size: 15px; }

/* ===== 页头（page-head / crumb / page-title / page-sub）===== */
.page-head { padding: 64px 0 36px; border-bottom: 1px solid var(--border); }
.crumb {
  font: 500 12px/1 var(--font-mono); letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 18px;
  display: flex; align-items: center; gap: 8px;
}
.crumb a { color: var(--muted); }
.crumb a:hover { color: var(--fg); }
h1.page-title {
  font-family: var(--font-display);
  font-size: clamp(32px, 4.4vw, 46px); line-height: 1.08;
  letter-spacing: -0.025em; font-weight: 600; margin-bottom: 14px;
}
.page-sub { font-size: 17px; color: var(--muted); max-width: 46em; line-height: 1.6; }
.page-meta { color: var(--muted); font-size: 13px; font-family: var(--font-mono); letter-spacing: 0.04em; }

/* ===== SECTION 共用 ===== */
section.block { padding: 88px 0; border-top: 1px solid var(--border); }
.sec-head { max-width: 640px; margin-bottom: 52px; }
.sec-kicker {
  font: 600 12px/1 var(--font-mono); letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 16px;
}
h2.sec-title {
  font-family: var(--font-display);
  font-size: clamp(30px, 3.4vw, 42px); line-height: 1.1;
  letter-spacing: -0.02em; font-weight: 600; margin-bottom: 16px;
}
.sec-sub { font-size: 17px; color: var(--muted); line-height: 1.6; }

/* ===== FAQ（通用折叠）===== */
.faq { max-width: 760px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid var(--border); }
.faq-q {
  width: 100%; background: none; border: 0; color: var(--fg);
  text-align: left; padding: 22px 0; font: 600 16px/1.4 var(--font-body);
  cursor: pointer; display: flex; justify-content: space-between;
  align-items: center; gap: 16px;
}
.faq-q .chev { flex-shrink: 0; width: 18px; height: 18px; transition: transform .25s; color: var(--muted); }
.faq-item.open .faq-q .chev { transform: rotate(45deg); color: var(--accent); }
.faq-a {
  max-height: 0; overflow: hidden; transition: max-height .3s ease;
  color: var(--muted); font-size: 15px; line-height: 1.7;
}
.faq-item.open .faq-a { max-height: 320px; padding-bottom: 22px; }

/* ===== 最终 CTA ===== */
.cta-band {
  margin: 0 28px 60px; padding: 64px 48px;
  background:
    radial-gradient(circle at 80% 20%, var(--accent-dim), transparent 50%),
    var(--surface);
  border: 1px solid var(--border); border-radius: 18px;
  text-align: center; max-width: 1124px; margin-left: auto; margin-right: auto;
}
.cta-band h2 {
  font-family: var(--font-display); font-size: clamp(28px, 3.2vw, 38px);
  font-weight: 600; letter-spacing: -0.02em; margin-bottom: 14px;
}
.cta-band p { color: var(--muted); margin-bottom: 28px; font-size: 16px; }

/* ===== FOOTER ===== */
footer { border-top: 1px solid var(--border); padding: 40px 0; margin-top: 20px; }
.foot-inner {
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 16px;
}
.foot-inner small { color: var(--muted); font-size: 13px; }
.foot-links { display: flex; gap: 22px; flex-wrap: wrap; }
.foot-links a { color: var(--muted); font-size: 13px; }
.foot-links a:hover { color: var(--fg); }
/* 友链区 */
.foot-friends {
  display: flex; align-items: center; gap: 16px;
  padding: 18px 0 0; margin-top: 18px;
  border-top: 1px solid var(--border); flex-wrap: wrap;
}
.foot-friends .ff-label {
  font: 600 11px/1 var(--font-mono); letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--muted);
}
.footer-links { display: flex; gap: 18px; list-style: none; flex-wrap: wrap; }
.footer-links li { display: flex; align-items: center; gap: 18px; }
.footer-links li:not(:last-child)::after {
  content: ''; width: 3px; height: 3px; border-radius: 50%; background: var(--border);
}
.footer-links a { font-size: 13px; color: var(--muted); transition: color .15s; }
.footer-links a:hover { color: var(--accent); }

/* ===== 长文 prose（隐私/条款/关于/博客 共用）===== */
article { padding: 44px 0 64px; }
.lead {
  font-size: 17px; line-height: 1.7; color: var(--fg-strong); margin-bottom: 30px;
  padding: 20px 22px; background: var(--surface);
  border: 1px solid var(--border); border-left: 2px solid var(--accent);
  border-radius: 0 10px 10px 0;
}
.lead strong { color: var(--fg); }
h2.sec {
  font-family: var(--font-display); font-size: 21px; font-weight: 600;
  letter-spacing: -0.015em; margin: 36px 0 12px;
  display: flex; align-items: baseline; gap: 12px;
}
h2.sec .n { font: 600 13px/1 var(--font-mono); color: var(--accent); letter-spacing: 0.06em; }
article p { font-size: 15.5px; line-height: 1.75; color: var(--fg-body); margin-bottom: 14px; }
article strong { color: var(--fg); font-weight: 600; }
article ul { margin: 0 0 16px 4px; }
article ul li {
  font-size: 15.5px; line-height: 1.75; color: var(--fg-body); margin-bottom: 8px;
  list-style: none; padding-left: 20px; position: relative;
}
article ul li::before {
  content: ''; position: absolute; left: 4px; top: 11px;
  width: 5px; height: 5px; border-radius: 50%; background: var(--accent);
}
article a { color: var(--accent); }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
  .nav-links { display: none; }
  section.block { padding: 60px 0; }
}