:root {
  --paper: #fbfaf7;
  --surface: #ffffff;
  --ink: #1f2933;
  --muted: #66727f;
  --line: #d7ddd7;
  --teal: #256f74;
  --teal-deep: #174a50;
  --accent: #b6523d;
  --gold: #b48a3c;
  --shadow: 0 16px 38px rgba(31, 41, 51, 0.10);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Noto Serif TC", "Microsoft JhengHei", "PingFang TC", serif;
  line-height: 1.85;
}

a { color: var(--teal); text-decoration-thickness: 1px; text-underline-offset: 4px; }
a:hover { color: var(--accent); }

.site-header {
  min-height: 520px;
  color: white;
  background-image: url("assets/book-cover.jpg");
  background-size: cover;
  background-position: center 42%;
  display: flex;
  align-items: flex-end;
}

.hero-inner {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  padding: 54px 0 68px;
}

.eyebrow {
  margin: 0 0 12px;
  text-shadow: 0 1px 10px rgba(0, 0, 0, 0.55);
  color: #f0d9a5;
  font-size: 0.92rem;
  letter-spacing: 0;
  font-weight: 700;
}

h1 {
  margin: 0;
  text-shadow: 0 2px 18px rgba(0, 0, 0, 0.42);
  font-size: 3rem;
  line-height: 1.2;
  letter-spacing: 0;
}

.hero-copy {
  max-width: 760px;
  text-shadow: 0 1px 12px rgba(0, 0, 0, 0.5);
  margin: 22px 0 0;
  color: rgba(255, 255, 255, 0.92);
  font-size: 1.12rem;
}

.topbar {
  background: var(--surface);
  border-bottom: 1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 5;
}

.topbar-inner {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
  min-height: 58px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}

.brand {
  color: var(--teal-deep);
  font-weight: 800;
  text-decoration: none;
}

.nav-link {
  color: var(--muted);
  font-size: 0.95rem;
  text-decoration: none;
}

.wrap {
  width: min(1120px, calc(100% - 40px));
  margin: 0 auto;
}

.lecture-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  padding: 44px 0 70px;
}

.lecture-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 22px 24px 24px;
  box-shadow: 0 8px 24px rgba(31, 41, 51, 0.06);
  text-decoration: none;
  color: inherit;
  min-height: 210px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.lecture-card:hover {
  border-color: rgba(37, 111, 116, 0.55);
  box-shadow: var(--shadow);
}

.lecture-no {
  color: var(--accent);
  font-weight: 800;
  font-size: 0.92rem;
}

.lecture-card h2 {
  margin: 0;
  color: var(--teal-deep);
  font-size: 1.28rem;
  line-height: 1.45;
  letter-spacing: 0;
}

.lecture-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.98rem;
}

.article-shell {
  padding: 46px 0 70px;
}

.article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  box-shadow: var(--shadow);
  padding: 46px min(7vw, 76px);
}

.article h1 {
  color: var(--teal-deep);
  font-size: 2.15rem;
  margin-bottom: 28px;
}

.article p {
  margin: 0 0 18px;
  font-size: 1.08rem;
  text-align: justify;
}

.promo {
  margin-top: 42px;
  padding: 28px 30px;
  border-top: 3px solid var(--gold);
  border-bottom: 1px solid var(--line);
  background: #f6f2e9;
}

.promo p {
  margin-bottom: 14px;
}

.promo a {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  font-weight: 800;
}

.pager {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  margin-top: 24px;
}

.pager a {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--teal-deep);
  padding: 12px 16px;
  text-decoration: none;
  font-weight: 700;
}

.pager a:hover {
  border-color: var(--teal);
  color: var(--accent);
}

.site-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  padding: 30px 0;
  font-size: 0.92rem;
}

@media (max-width: 760px) {
  .site-header { min-height: 430px; }
  h1 { font-size: 2.25rem; }
  .hero-copy { font-size: 1rem; }
  .intro-grid { grid-template-columns: 1fr; gap: 26px; padding: 34px 0 28px; }
  .lecture-grid { grid-template-columns: 1fr; padding-top: 30px; }
  .article { padding: 30px 22px; }
  .article h1 { font-size: 1.72rem; }
  .article p { font-size: 1rem; }
  .pager { flex-direction: column; }
}


.book-intro {
  background: #ffffff;
  border-bottom: 1px solid var(--line);
}

.intro-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 44px;
  padding: 44px 0 36px;
}

.intro-block h2 {
  margin: 0 0 14px;
  color: var(--teal-deep);
  font-size: 1.36rem;
  letter-spacing: 0;
}

.intro-block p {
  margin: 0;
  color: #3d4852;
  font-size: 1.04rem;
  text-align: justify;
}




.feature-block {
  border-left: 4px solid var(--gold);
  padding-left: 22px;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.nav-cta {
  background: var(--teal);
  color: #ffffff;
  border-radius: 8px;
  padding: 7px 12px;
  font-weight: 800;
}

.nav-cta:hover {
  background: var(--accent);
  color: #ffffff;
}

@media (max-width: 760px) {
  .topbar-inner {
    align-items: flex-start;
    flex-direction: column;
    padding: 12px 0;
  }

  .nav-actions {
    justify-content: flex-start;
    gap: 12px;
  }
}