:root {
  color-scheme: light;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: #17231d;
  background: #f4f7f2;
  line-height: 1.7;
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; }
a { color: inherit; }
img { max-width: 100%; }
.shell { width: min(1080px, calc(100% - 32px)); margin: 0 auto; padding: 48px 0 72px; }
.site-header { width: min(1080px, calc(100% - 32px)); margin: 0 auto; padding: 22px 0; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.site-header nav { display: flex; gap: 20px; }
.site-header a { text-decoration: none; }
.brand { font-weight: 800; }
.hero { padding: clamp(32px, 7vw, 72px); border-radius: 28px; background: #173f2c; color: #f7fbf4; }
.eyebrow { margin: 0 0 14px; font-size: 12px; letter-spacing: .14em; color: #52705c; }
.hero .eyebrow { color: #a9d6b8; }
h1 { margin: 0; font-size: clamp(36px, 7vw, 64px); line-height: 1.12; }
h2, h3 { line-height: 1.35; }
.lead { margin: 24px 0 0; font-size: clamp(18px, 3vw, 24px); color: #dceade; }
.lead-text { max-width: 760px; color: #53665a; font-size: 19px; }
.actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 32px; }
.button { display: inline-flex; align-items: center; justify-content: center; min-height: 44px; padding: 10px 18px; border: 1px solid transparent; border-radius: 10px; background: #d8f36a; color: #17231d; font-weight: 700; text-decoration: none; cursor: pointer; }
.button.secondary { border-color: #74927e; background: transparent; color: #f7fbf4; }
.button.secondary-light { border-color: #aab8ad; background: transparent; color: #173f2c; }
.search-panel, .content-panel, .download-panel { margin: 24px 0; padding: clamp(22px, 4vw, 34px); border: 1px solid #d6dfd4; border-radius: 18px; background: #fff; }
.search-panel label { display: block; margin-bottom: 10px; font-weight: 700; }
.search-panel input { width: 100%; min-height: 48px; padding: 10px 14px; border: 1px solid #aab8ad; border-radius: 10px; font: inherit; }
.search-result-list { display: grid; gap: 8px; margin-top: 16px; }
.search-result-list a { display: grid; padding: 12px 14px; border-radius: 10px; background: #f4f7f2; text-decoration: none; }
.search-result-list small { color: #607066; }
.section-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 16px; margin: 36px 0 16px; }
.section-heading h2 { margin: 0; }
.section-heading span { color: #607066; font-size: 13px; overflow-wrap: anywhere; text-align: right; }
.card-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.resource-card { padding: 26px; border: 1px solid #d6dfd4; border-radius: 18px; background: #fff; }
.resource-card h2, .resource-card h3 { margin: 4px 0 12px; }
.resource-card a { text-decoration: none; }
.text-link { color: #1d5b3b; font-weight: 700; }
.page-heading { padding: 24px 0; }
.resource-detail { display: grid; grid-template-columns: 1fr 240px; align-items: center; gap: 40px; }
.cover { width: 100%; border-radius: 18px; box-shadow: 0 16px 40px #173f2c24; }
.content-panel h2 { margin-top: 0; }
.prewrap { white-space: pre-wrap; }
dl { display: grid; grid-template-columns: 110px 1fr; gap: 8px 16px; }
dt { color: #607066; }
dd { margin: 0; }
.file-list { padding: 0; list-style: none; }
.file-list li { display: flex; justify-content: space-between; gap: 16px; padding: 12px 0; border-bottom: 1px solid #e4e9e3; }
.file-list small { color: #607066; }
.attribution { color: #53665a; font-size: 14px; }
.keyword { display: inline-block; margin: 12px 0; padding: 8px 22px; border-radius: 10px; background: #173f2c; color: #d8f36a; font-size: 32px; font-weight: 800; }
.delivery-status { padding: 14px; border-radius: 10px; background: #f4f7f2; }
.delivery-choices { display: flex; flex-wrap: wrap; gap: 10px; margin: 20px 0; }
.delivery-choice.active { border-color: #173f2c; background: #d8f36a; }
.pairing-panel { margin: 22px 0; padding: 20px; border: 1px solid #d6dfd4; border-radius: 14px; }
.wechat-qr { display: block; width: min(220px, 100%); height: auto; margin: 16px 0; }
.wechat-avatar { display: block; width: 96px; height: 96px; margin: 16px 0; border-radius: 50%; }
.manual-login { margin: 20px 0; }
.manual-login form { display: grid; gap: 12px; margin-top: 16px; }
.manual-login input { width: min(320px, 100%); min-height: 46px; padding: 10px 12px; border: 1px solid #aab8ad; border-radius: 10px; font: inherit; }
button.button { border: 0; font: inherit; }
.chapter-list { padding: 0; list-style: none; counter-reset: chapters; }
.chapter-list li { display: flex; justify-content: space-between; gap: 18px; padding: 16px 4px; border-bottom: 1px solid #d6dfd4; }
.chapter-list a { color: #173f2c; font-weight: 700; text-decoration: none; }
.chapter-list span { white-space: nowrap; color: #607066; }
.breadcrumb { margin-bottom: 20px; color: #607066; }
.book-chapter { padding: clamp(24px, 6vw, 64px); border: 1px solid #d6dfd4; border-radius: 20px; background: #fff; }
.book-chapter h1 { font-size: clamp(32px, 5vw, 48px); }
.chapter-intro { padding-bottom: 24px; border-bottom: 1px solid #d6dfd4; }
.book-item { padding-top: 32px; scroll-margin-top: 20px; }
.book-item h2 { font-size: 25px; }
.book-item li { margin: 8px 0; }
.book-item a, .chapter-intro a { color: #1d5b3b; overflow-wrap: anywhere; }
.chapter-nav { display: flex; justify-content: space-between; gap: 12px; margin-top: 24px; }
.site-footer { width: min(1080px, calc(100% - 32px)); margin: 0 auto; padding: 24px 0 40px; border-top: 1px solid #d6dfd4; color: #607066; font-size: 14px; }
.muted { color: #607066; }
.error { color: #a42727; }
@media (max-width: 700px) {
  .shell { padding-top: 24px; }
  .card-grid, .resource-detail { grid-template-columns: 1fr; }
  .cover { width: min(240px, 70%); }
  .section-heading { align-items: flex-start; flex-direction: column; }
  .section-heading span { text-align: left; }
  .file-list li { flex-direction: column; gap: 2px; }
}