:root {
  --bg: #f3ebd8;
  --bg-strong: #e6d4af;
  --surface: rgba(255, 250, 240, 0.76);
  --surface-strong: rgba(255, 248, 232, 0.94);
  --ink: #2d241b;
  --muted: #665a4a;
  --accent: #ab4e2b;
  --accent-dark: #81371d;
  --line: rgba(67, 46, 26, 0.16);
  --success: #336b4d;
  --danger: #8c2f2f;
  --shadow: 0 22px 70px rgba(64, 40, 18, 0.14);
  --radius: 24px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: "Trebuchet MS", "Gill Sans", sans-serif;
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.6), transparent 28%),
    radial-gradient(circle at right 20%, rgba(171, 78, 43, 0.14), transparent 18%),
    linear-gradient(135deg, #efe3c7 0%, #f5eedf 46%, #e7cfa9 100%);
}

body::before,
body::after {
  content: "";
  position: fixed;
  inset: auto;
  pointer-events: none;
  z-index: 0;
}

body::before {
  width: 28rem;
  height: 28rem;
  top: -8rem;
  right: -8rem;
  border-radius: 50%;
  background: rgba(113, 56, 34, 0.1);
  filter: blur(8px);
}

body::after {
  width: 22rem;
  height: 22rem;
  bottom: -7rem;
  left: -6rem;
  border-radius: 50%;
  background: rgba(34, 74, 58, 0.12);
  filter: blur(12px);
}

.page-shell {
  position: relative;
  z-index: 1;
  width: min(1180px, calc(100% - 2rem));
  margin: 0 auto;
  padding: 2rem 0 4rem;
}

.hero,
.section,
.stats-grid,
.quiz-shell {
  animation: rise 620ms ease both;
}

.hero {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(280px, 0.75fr);
  gap: 1.25rem;
  align-items: stretch;
  margin-bottom: 1.5rem;
}

.hero-copy,
.hero-panel,
.section,
.stat-card,
.topic-card,
.flashcard,
.quiz-item,
.check-card {
  border: 1px solid var(--line);
  box-shadow: var(--shadow);
  backdrop-filter: blur(10px);
}

.hero-copy,
.hero-panel {
  padding: 2rem;
  border-radius: calc(var(--radius) + 6px);
  background: linear-gradient(180deg, var(--surface-strong), rgba(255, 247, 228, 0.82));
}

.eyebrow {
  margin: 0 0 0.6rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.76rem;
  color: var(--accent-dark);
}

h1,
h2,
h3 {
  margin: 0;
  font-family: Baskerville, "Palatino Linotype", "Book Antiqua", serif;
  line-height: 1.02;
}

h1 {
  font-size: clamp(2.8rem, 6vw, 5.3rem);
  max-width: 10ch;
}

h2 {
  font-size: clamp(1.8rem, 4vw, 3rem);
}

h3 {
  font-size: 1.35rem;
  margin-bottom: 0.75rem;
}

.lead,
p,
li {
  font-size: 1.02rem;
  line-height: 1.6;
}

.lead {
  max-width: 58ch;
  color: var(--muted);
  margin: 1rem 0 1.5rem;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
}

.button,
.chip,
.flashcard-toggle,
.answer-button {
  border: 0;
  border-radius: 999px;
  font: inherit;
  cursor: pointer;
  transition: transform 180ms ease, background-color 180ms ease, color 180ms ease,
    box-shadow 180ms ease;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.8rem;
  padding: 0 1.2rem;
  text-decoration: none;
}

.button:hover,
.chip:hover,
.flashcard:hover,
.answer-button:hover {
  transform: translateY(-2px);
}

.button-primary {
  background: var(--accent);
  color: #fff5eb;
}

.button-secondary {
  background: rgba(85, 57, 34, 0.1);
  color: var(--ink);
}

.focus-list,
.check-card ul {
  margin: 1rem 0 0;
  padding-left: 1.1rem;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.stat-card {
  display: grid;
  gap: 0.35rem;
  padding: 1.3rem 1.35rem;
  border-radius: 20px;
  background: rgba(255, 248, 236, 0.68);
}

.stat-number {
  font-family: Baskerville, "Palatino Linotype", serif;
  font-size: 2.7rem;
  color: var(--accent-dark);
}

.stat-label {
  color: var(--muted);
}

.section {
  margin-top: 1rem;
  padding: 1.8rem;
  border-radius: calc(var(--radius) + 2px);
  background: rgba(255, 249, 239, 0.7);
}

.section-heading {
  display: grid;
  gap: 0.35rem;
  margin-bottom: 1.5rem;
}

.topic-grid,
.checklist-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.topic-card,
.check-card {
  padding: 1.25rem;
  border-radius: 22px;
  background: rgba(255, 252, 245, 0.82);
}

.timeline-track {
  display: grid;
  gap: 0.8rem;
}

.timeline-item {
  position: relative;
  display: grid;
  grid-template-columns: 120px minmax(0, 1fr);
  gap: 1rem;
  padding: 1rem 1rem 1rem 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: 100px;
  top: 0.2rem;
  bottom: -0.2rem;
  width: 2px;
  background: rgba(171, 78, 43, 0.28);
}

.timeline-item:last-child::before {
  bottom: 50%;
}

.timeline-year {
  position: relative;
  font-family: Baskerville, "Palatino Linotype", serif;
  font-size: 1.9rem;
  color: var(--accent-dark);
  padding-right: 1rem;
}

.timeline-year::after {
  content: "";
  position: absolute;
  right: 0;
  top: 0.6rem;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 6px rgba(171, 78, 43, 0.14);
}

.timeline-body {
  background: rgba(255, 252, 245, 0.72);
  border: 1px solid var(--line);
  border-radius: 18px;
  padding: 1rem 1.1rem;
}

.toolbar {
  display: grid;
  gap: 0.8rem;
  margin-bottom: 1rem;
}

.chip-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
}

.chip {
  padding: 0.65rem 1rem;
  background: rgba(100, 64, 39, 0.09);
  color: var(--ink);
}

.chip.is-active {
  background: var(--accent-dark);
  color: #fff6ea;
}

.toolbar-hint {
  margin: 0;
  color: var(--muted);
}

.flashcard-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
}

.flashcard {
  position: relative;
  min-height: 250px;
  padding: 1.1rem;
  border-radius: 24px;
  background:
    linear-gradient(180deg, rgba(255, 250, 241, 0.95), rgba(248, 237, 217, 0.92));
  overflow: hidden;
}

.flashcard::after {
  content: "";
  position: absolute;
  inset: auto -15% -30% auto;
  width: 9rem;
  height: 9rem;
  border-radius: 50%;
  background: rgba(171, 78, 43, 0.08);
}

.flashcard-inner {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 0.8rem;
  height: 100%;
}

.flashcard-tag {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  padding: 0.32rem 0.65rem;
  border-radius: 999px;
  background: rgba(51, 107, 77, 0.12);
  color: var(--success);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.flashcard-title {
  font-size: 1.28rem;
}

.flashcard-answer {
  display: none;
  color: var(--muted);
}

.flashcard.is-flipped .flashcard-answer {
  display: block;
}

.flashcard.is-flipped .flashcard-question {
  display: none;
}

.flashcard-toggle {
  align-self: end;
  justify-self: start;
  padding: 0.65rem 0.95rem;
  background: rgba(85, 57, 34, 0.1);
  color: var(--ink);
}

.quiz-shell {
  display: grid;
  gap: 1rem;
}

.quiz-status {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 1.1rem;
  border-radius: 18px;
  background: rgba(255, 249, 238, 0.78);
  border: 1px solid var(--line);
}

.status-label,
.status-value {
  margin: 0;
}

.status-label {
  color: var(--muted);
}

.status-value {
  font-size: 1.6rem;
  font-family: Baskerville, "Palatino Linotype", serif;
}

.quiz-list {
  display: grid;
  gap: 0.9rem;
}

.quiz-item {
  padding: 1.2rem;
  border-radius: 20px;
  background: rgba(255, 252, 246, 0.84);
}

.quiz-question {
  margin: 0 0 0.85rem;
  font-size: 1.1rem;
}

.answer-list {
  display: grid;
  gap: 0.6rem;
}

.answer-button {
  text-align: left;
  width: 100%;
  padding: 0.8rem 1rem;
  background: rgba(96, 72, 43, 0.08);
  color: var(--ink);
}

.answer-button.correct {
  background: rgba(51, 107, 77, 0.16);
  color: var(--success);
}

.answer-button.incorrect {
  background: rgba(140, 47, 47, 0.14);
  color: var(--danger);
}

.answer-button:disabled {
  cursor: default;
  opacity: 1;
}

.quiz-feedback {
  margin: 0.75rem 0 0;
  color: var(--muted);
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@media (max-width: 960px) {
  .hero,
  .topic-grid,
  .checklist-grid,
  .flashcard-grid,
  .stats-grid {
    grid-template-columns: 1fr 1fr;
  }

  .hero {
    grid-template-columns: 1fr;
  }

  .flashcard-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 700px) {
  .page-shell {
    width: min(100% - 1rem, 1180px);
    padding-top: 1rem;
  }

  .stats-grid,
  .topic-grid,
  .checklist-grid,
  .flashcard-grid {
    grid-template-columns: 1fr;
  }

  .section,
  .hero-copy,
  .hero-panel {
    padding: 1.2rem;
  }

  .timeline-item {
    grid-template-columns: 1fr;
    padding-right: 0;
  }

  .timeline-item::before {
    left: 0.3rem;
    top: 2.45rem;
  }

  .timeline-year {
    padding-left: 1.5rem;
  }

  .timeline-year::after {
    left: 0;
    right: auto;
  }

  .quiz-status {
    align-items: flex-start;
    flex-direction: column;
  }
}