/* 身体结构健康公益教育 — 共享样式，移动优先 */
:root {
  --ink: #1f2a2e;
  --ink-soft: #4a595e;
  --paper: #fbfaf6;
  --card: #ffffff;
  --line: #e6e2d8;
  --brand: #2f6d5f;      /* 沉静的青绿，传达可信与安宁 */
  --brand-dark: #234f45;
  --brand-soft: #eef4f1;
  --accent: #c08a3e;     /* 暖金，用于强调 */
  --warn-bg: #fbf1e7;
  --warn-line: #e2b483;
  --warn-ink: #8a5320;
  --radius: 14px;
  --maxw: 760px;
  --shadow: 0 1px 2px rgba(31,42,46,.06), 0 6px 20px rgba(31,42,46,.05);
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
    "Microsoft YaHei", "Noto Sans SC", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.75;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--brand-dark); }

/* ---- 布局 ---- */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 20px; }
main { padding: 8px 0 48px; }
section { margin: 40px 0; }
h1, h2, h3 { line-height: 1.35; color: var(--ink); }
h1 { font-size: 1.7rem; margin: .2em 0 .4em; }
h2 { font-size: 1.3rem; margin: 1.6em 0 .5em; }
h3 { font-size: 1.08rem; margin: 1.2em 0 .3em; }
p { margin: .6em 0; color: var(--ink-soft); }
.lead { font-size: 1.12rem; color: var(--ink); }

/* ---- 顶部导航 ---- */
header.site {
  position: sticky; top: 0; z-index: 20;
  background: rgba(251,250,246,.92);
  backdrop-filter: saturate(1.2) blur(8px);
  border-bottom: 1px solid var(--line);
}
.nav { max-width: var(--maxw); margin: 0 auto; padding: 12px 20px; }
.nav-top { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.brand { font-weight: 700; color: var(--brand-dark); text-decoration: none; font-size: 1.05rem; letter-spacing: .5px; }
.brand small { display: block; font-weight: 400; font-size: .72rem; color: var(--ink-soft); letter-spacing: 0; }
.menu-toggle {
  display: inline-flex; border: 1px solid var(--line); background: var(--card);
  border-radius: 10px; padding: 8px 12px; font-size: .9rem; color: var(--ink); cursor: pointer;
}
.menu { list-style: none; margin: 10px 0 0; padding: 0; display: none; }
.menu.open { display: block; }
.menu li { border-top: 1px solid var(--line); }
.menu a { display: block; padding: 12px 4px; text-decoration: none; color: var(--ink); }
.menu a.active { color: var(--brand-dark); font-weight: 600; }

@media (min-width: 720px) {
  .menu-toggle { display: none; }
  .menu { display: flex !important; gap: 20px; margin: 0; }
  .menu li { border: 0; }
  .menu a { padding: 4px 0; }
}

/* ---- 首屏 ---- */
.hero { background: linear-gradient(180deg, var(--brand-soft), var(--paper)); border-bottom: 1px solid var(--line); }
.hero .wrap { padding-top: 40px; padding-bottom: 40px; }
.hero h1 { font-size: 2rem; }
.hero .sub { font-size: 1.15rem; color: var(--ink-soft); max-width: 34em; }
.trust { margin-top: 18px; font-weight: 600; color: var(--brand-dark); border-left: 3px solid var(--brand); padding-left: 12px; }

/* ---- 按钮 ---- */
.btns { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 22px; }
.btn {
  display: inline-block; text-decoration: none; padding: 13px 20px; border-radius: 12px;
  font-weight: 600; font-size: 1rem; text-align: center;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:active { background: var(--brand-dark); }
.btn-ghost { background: var(--card); color: var(--brand-dark); border: 1px solid var(--line); }

/* ---- 卡片 ---- */
.cards { display: grid; grid-template-columns: 1fr; gap: 14px; margin-top: 18px; }
@media (min-width: 640px) { .cards { grid-template-columns: 1fr 1fr; } }
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 18px; box-shadow: var(--shadow);
}
.card h3 { margin-top: 0; color: var(--brand-dark); }
.card p { margin-bottom: 0; }
.card a.more { display: inline-block; margin-top: 10px; font-weight: 600; text-decoration: none; }

/* ---- 提示框 ---- */
.note {
  background: var(--warn-bg); border: 1px solid var(--warn-line); color: var(--warn-ink);
  border-radius: var(--radius); padding: 14px 16px; margin: 20px 0;
}
.note strong { color: var(--warn-ink); }
.info { background: var(--brand-soft); border: 1px solid #cfe0d9; border-radius: var(--radius); padding: 14px 16px; margin: 20px 0; color: var(--ink); }

/* ---- 步骤 / 列表 ---- */
.steps { list-style: none; padding: 0; margin: 18px 0; counter-reset: s; }
.steps li {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 16px 16px 16px 56px; margin-bottom: 12px; position: relative; box-shadow: var(--shadow);
}
.steps li::before {
  counter-increment: s; content: counter(s);
  position: absolute; left: 14px; top: 16px; width: 28px; height: 28px;
  background: var(--brand); color: #fff; border-radius: 50%;
  display: flex; align-items: center; justify-content: center; font-weight: 700; font-size: .9rem;
}
.steps li strong { display: block; color: var(--ink); margin-bottom: 2px; }

ul.check { list-style: none; padding: 0; }
ul.check li { padding: 6px 0 6px 26px; position: relative; color: var(--ink-soft); }
ul.check li::before { content: "✓"; position: absolute; left: 0; color: var(--brand); font-weight: 700; }
ul.red li::before { content: "⚑"; color: var(--accent); }
ul.no li::before { content: "✕"; color: #b05a4a; }

/* ---- 折叠文章 ---- */
details.qa {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 4px 16px; margin: 12px 0; box-shadow: var(--shadow);
}
details.qa summary {
  cursor: pointer; font-weight: 600; color: var(--ink); padding: 14px 0; list-style: none;
  display: flex; justify-content: space-between; align-items: center; gap: 10px;
}
details.qa summary::-webkit-details-marker { display: none; }
details.qa summary::after { content: "＋"; color: var(--brand); font-weight: 700; }
details.qa[open] summary::after { content: "－"; }
details.qa .body { padding-bottom: 14px; border-top: 1px solid var(--line); margin-top: -1px; padding-top: 12px; }
details.qa .body p:first-child { margin-top: 0; }

.tag { display: inline-block; font-size: .78rem; color: var(--brand-dark); background: var(--brand-soft); border-radius: 999px; padding: 3px 10px; margin: 0 6px 6px 0; }

.price {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  padding: 20px; box-shadow: var(--shadow); margin: 18px 0;
}
.price .amount { font-size: 1.6rem; font-weight: 700; color: var(--brand-dark); }
.price .amount small { font-size: .95rem; font-weight: 400; color: var(--ink-soft); }

/* ---- 页脚 ---- */
footer.site { border-top: 1px solid var(--line); background: #f4f2ea; margin-top: 40px; }
footer.site .wrap { padding: 28px 20px 40px; }
footer.site p { font-size: .85rem; color: #6b7378; margin: .5em 0; }
footer.site a { color: #4a595e; }
.foot-nav { display: flex; flex-wrap: wrap; gap: 14px; margin-bottom: 14px; }
.foot-nav a { text-decoration: none; font-weight: 600; color: var(--brand-dark); font-size: .9rem; }
.disclaimer { border-top: 1px solid var(--line); padding-top: 14px; margin-top: 14px; }