* { margin: 0; padding: 0; box-sizing: border-box; }
body { background: #2a2117; display: flex; justify-content: center; padding: 60px 0; }
.book {
  width: 1440px; background: linear-gradient(180deg, #fbf7ee 0%, #f7f0e2 100%);
  color: #221b14; font-family: Georgia, "Times New Roman", "Songti SC", "STSong", serif;
  padding: 100px 130px 110px; position: relative;
}
.book::after {
  content: ""; position: absolute; top: 0; bottom: 0; left: 72px; width: 1px;
  background: linear-gradient(180deg, transparent, #e3d7bd 20%, #e3d7bd 80%, transparent);
}
.running-head {
  display: flex; justify-content: space-between; font-size: 14px; letter-spacing: 3px;
  color: #8a7a5f; text-transform: uppercase; padding-bottom: 22px;
  border-bottom: 1px solid #d9ccb1;
}
.chapter-open { margin-top: 90px; text-align: center; }
.chapter-label { font-size: 18px; letter-spacing: 8px; color: #b23a2e; text-transform: uppercase; }
.chapter-title { font-size: 64px; margin-top: 18px; letter-spacing: 1px; }
.chapter-zh { font-size: 22px; color: #8a7a5f; letter-spacing: 10px; margin-top: 12px; }
.chapter-rule { width: 120px; height: 2px; background: #b8893b; margin: 34px auto 0; }
.lede {
  margin: 56px auto 0; max-width: 900px; font-size: 21px; line-height: 1.75;
  color: #3f3427; font-style: italic; text-align: center;
}
.content { margin-top: 66px; }
section { margin-bottom: 58px; }
.sec-head {
  display: flex; align-items: baseline; gap: 18px; border-bottom: 1px solid #d9ccb1; padding-bottom: 10px; margin-bottom: 24px;
}
.sec-num { font-size: 20px; color: #b8893b; font-style: italic; }
.sec-title { font-size: 30px; letter-spacing: 0.5px; }
.sec-zh { font-size: 16px; color: #8a7a5f; letter-spacing: 3px; }
p { font-size: 19px; line-height: 1.85; margin-bottom: 18px; color: #2d2519; }
.cn { color: #b23a2e; }
.box {
  border: 1px solid #d9ccb1; border-left: 4px solid #b8893b; background: rgba(184,137,59,0.07);
  border-radius: 6px; padding: 20px 24px; margin: 26px 0; font-size: 17.5px; line-height: 1.75; color: #3f3427;
}
.box.red { border-left-color: #b23a2e; background: rgba(178,58,46,0.05); }
.box b.tag { display: block; font-size: 14px; letter-spacing: 3px; text-transform: uppercase; color: #b8893b; margin-bottom: 8px; }
.box.red b.tag { color: #b23a2e; }
ul.check { list-style: none; margin: 22px 0; display: grid; gap: 12px; }
ul.check li { font-size: 18.5px; display: flex; gap: 14px; align-items: baseline; line-height: 1.6; }
ul.check li::before { content: "☐"; color: #b8893b; font-size: 20px; }
table.guide { width: 100%; border-collapse: collapse; margin: 22px 0; font-size: 17.5px; }
table.guide th {
  text-align: left; font-size: 14px; letter-spacing: 2px; text-transform: uppercase; color: #b23a2e;
  border-bottom: 2px solid #b23a2e; padding: 10px 12px;
}
table.guide td { border-bottom: 1px solid #d9ccb1; padding: 12px; line-height: 1.6; vertical-align: top; }
.endmark { text-align: center; margin-top: 70px; color: #b23a2e; font-size: 24px; letter-spacing: 10px; }
.foot {
  margin-top: 70px; padding-top: 24px; border-top: 1px solid #d9ccb1;
  display: flex; justify-content: space-between; font-size: 14px; letter-spacing: 3px;
  color: #8a7a5f; text-transform: uppercase;
}
.lang-switch {
  position: fixed; top: 18px; right: 24px; z-index: 100;
  background: rgba(251,247,238,0.96); border: 1px solid #c9bda5; border-radius: 999px;
  padding: 7px 18px; font-size: 14px; letter-spacing: 1px; color: #8a7a5f;
  font-family: Georgia, "Times New Roman", "PingFang SC", "Microsoft YaHei", serif;
  box-shadow: 0 4px 14px rgba(34,27,20,0.14);
}
.lang-switch a { color: #b23a2e; text-decoration: none; font-weight: 700; }
.lang-switch .on { color: #221b14; font-weight: 700; }