/* 粒序云官网公开页共享样式（关于我们/联系我们/隐私政策/用户服务协议/迭代日志）
   与 landing.html 同一设计体系；非经营性备案页面：无价格、无付费入口 */
:root {
  --primary: #6366F1;
  --primary-dark: #4F46E5;
  --bg: #F8FAFF;
  --surface: #FFFFFF;
  --text: #1E293B;
  --text-light: #64748B;
  --border: #E2E8F0;
  --gradient: linear-gradient(135deg, #6366F1, #A78BFA);
  --shadow-sm: 0 1px 3px rgba(0,0,0,.06);
  --shadow-md: 0 8px 24px rgba(99,102,241,.1);
  --radius: 16px;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body { font-family: -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif; background: var(--bg); color: var(--text); line-height: 1.8; }
a { text-decoration: none; color: inherit; }

/* ===== Nav ===== */
.nav { position: sticky; top: 0; z-index: 50; background: rgba(248,250,255,.85); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); }
.nav-inner { max-width: 1180px; margin: 0 auto; padding: 14px 24px; display: flex; align-items: center; justify-content: space-between; }
.nav-logo { display: flex; align-items: center; gap: 10px; font-size: 20px; font-weight: 800; color: var(--primary); }
.nav-logo span { font-size: 28px; }
.nav-actions { display: flex; gap: 16px; align-items: center; flex-wrap: wrap; }
.nav-link { font-size: 14px; color: var(--text-light); font-weight: 500; transition: color .2s; }
.nav-link:hover { color: var(--primary); }
.btn-nav { background: var(--gradient); color: #fff; border: none; padding: 9px 22px; border-radius: 999px; font-size: 14px; font-weight: 600; cursor: pointer; transition: all .25s; display: inline-block; }
.btn-nav:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }

/* ===== 页面主体 ===== */
.page { max-width: 860px; margin: 0 auto; padding: 56px 24px 80px; }
.page-header { text-align: center; margin-bottom: 40px; }
.page-header h1 { font-size: 34px; font-weight: 800; letter-spacing: -.5px; margin-bottom: 10px; }
.page-header .sub { font-size: 14px; color: var(--text-light); }
.card { background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius); padding: 32px 36px; margin-bottom: 20px; box-shadow: var(--shadow-sm); }
.card h2 { font-size: 20px; font-weight: 700; margin: 26px 0 10px; color: var(--text); }
.card h2:first-child { margin-top: 0; }
.card p, .card li { font-size: 14.5px; color: var(--text-light); line-height: 1.9; }
.card ul, .card ol { padding-left: 22px; margin: 8px 0; }
.card strong { color: var(--text); }
.notice { background: #EEF2FF; border: 1px solid #C7D2FE; border-radius: 12px; padding: 16px 20px; font-size: 14px; color: var(--primary-dark); margin: 16px 0; }

/* ===== 按钮 ===== */
.btn-primary { background: var(--gradient); color: #fff; border: none; padding: 13px 30px; border-radius: 999px; font-size: 15px; font-weight: 600; cursor: pointer; transition: all .25s; display: inline-block; }
.btn-primary:hover { transform: translateY(-2px); box-shadow: var(--shadow-md); }
.btn-outline { background: transparent; color: var(--text); border: 1.5px solid var(--border); padding: 13px 30px; border-radius: 999px; font-size: 15px; font-weight: 600; cursor: pointer; transition: all .25s; display: inline-block; }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }

/* ===== 表单（联系我们：仅后台接收，页面不展示留言内容）===== */
.form-row { margin-bottom: 16px; }
.form-row label { display: block; font-size: 14px; font-weight: 600; margin-bottom: 6px; }
.form-row input, .form-row textarea { width: 100%; padding: 12px 14px; border: 1px solid var(--border); border-radius: 10px; font-size: 14px; font-family: inherit; background: var(--bg); color: var(--text); }
.form-row input:focus, .form-row textarea:focus { outline: none; border-color: var(--primary); background: #fff; }
.form-tip { font-size: 13px; color: var(--text-light); margin-top: 12px; }
.form-result { margin-top: 14px; font-size: 14px; font-weight: 600; }
.form-result.ok { color: #059669; }
.form-result.err { color: #DC2626; }

/* ===== Footer（与 landing.html 完全一致：备案展示位 + 主体信息）===== */
.footer { border-top: 1px solid var(--border); padding: 32px 24px; background: var(--surface); }
.footer-inner { max-width: 1180px; margin: 0 auto; display: flex; flex-direction: column; align-items: center; text-align: center; gap: 14px; }
.footer-logo { font-size: 18px; font-weight: 700; color: var(--primary); }
.footer-links { display: flex; gap: 20px; flex-wrap: wrap; justify-content: center; }
.footer-links a { font-size: 14px; color: var(--text-light); transition: color .2s; }
.footer-links a:hover { color: var(--primary); }
.footer-copy { font-size: 13px; color: var(--text-light); line-height: 1.9; }

/* ===== 迭代日志 ===== */
.post { padding: 24px 0; border-bottom: 1px solid var(--border); }
.post:last-child { border-bottom: none; }
.post .date { font-size: 13px; color: var(--primary); font-weight: 700; margin-bottom: 6px; }
.post h3 { font-size: 17px; font-weight: 700; margin-bottom: 8px; }
.post p { font-size: 14.5px; color: var(--text-light); }

@media (max-width: 640px) {
  .page { padding: 36px 16px 60px; }
  .page-header h1 { font-size: 26px; }
  .card { padding: 24px 20px; }
  .nav-actions .nav-link { display: none; }
}