:root {
  color-scheme: light;
  --bg: #FBF7F0;
  --text: #222222;
  --heading: #3A2A1A;
  --accent: #D9C5A3;
  --footer-bg: #3A2A1A;
  --footer-text: #FBF7F0;
}

* {
  box-sizing: border-box;
}

html, body {
  background-color: #FBF7F0 !important;
  color: #222222 !important;
  margin: 0;
  padding: 0;
}

body {
  font-family: system-ui, -apple-system, "Hiragino Kaku Gothic ProN", sans-serif;
  font-size: 16px;
  line-height: 1.7;
}

.lecture-banner {
  background-color: var(--accent);
  color: var(--heading);
  text-align: center;
  padding: 12px 24px;
  font-size: 0.9rem;
  font-weight: bold;
}

.container {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 24px;
}

header {
  text-align: center;
  margin-top: 3rem;
}

h1 {
  font-size: 2.5rem;
  color: var(--heading);
  letter-spacing: 0.2em;
  margin: 0;
}

section {
  margin-top: 3rem;
}

h2 {
  font-size: 1.6rem;
  color: var(--heading);
  border-bottom: 2px solid var(--accent);
  padding-bottom: 0.4rem;
  margin-bottom: 1.2rem;
}

h3 {
  font-size: 1.15rem;
  color: var(--heading);
  margin-top: 1.8rem;
  margin-bottom: 0.6rem;
}

p {
  margin: 0.6rem 0;
}

ul {
  padding-left: 1.4rem;
  margin: 0.6rem 0;
}

li {
  margin: 0.3rem 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin: 0.6rem 0 1rem;
}

th, td {
  text-align: left;
  padding: 10px 12px;
  border-bottom: 1px solid var(--accent);
}

th {
  color: var(--heading);
  font-weight: bold;
  background-color: rgba(217, 197, 163, 0.25);
}

td:last-child, th:last-child {
  text-align: right;
}

.note {
  font-size: 0.9rem;
  color: var(--heading);
  margin: 0.4rem 0;
}

footer {
  background-color: var(--footer-bg);
  color: var(--footer-text);
  text-align: center;
  padding: 24px;
  margin-top: 4rem;
  font-size: 0.85rem;
}