/* ============================================================
   Covered Dish — Design System
   White background, charcoal illustration aesthetic
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&family=Playfair+Display:ital,wght@0,400;0,700;1,400&display=swap');

/* === Reset & Base === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --white: #ffffff;
  --off-white: #fafaf8;
  --warm-gray-50: #f5f4f0;
  --warm-gray-100: #ebe9e3;
  --warm-gray-200: #d4d0c8;
  --warm-gray-400: #9e9888;
  --warm-gray-600: #6b6558;
  --warm-gray-800: #3d382e;
  --charcoal: #2a2520;
  --ink: #1a1714;
  --accent-warm: #8b7355;
  --accent-copper: #b87333;
  --accent-sage: #7a8b6f;
  --accent-clay: #c4703f;
  --shadow-sm: 0 1px 3px rgba(42, 37, 32, 0.06);
  --shadow-md: 0 4px 12px rgba(42, 37, 32, 0.08);
  --shadow-lg: 0 8px 30px rgba(42, 37, 32, 0.12);
  --shadow-xl: 0 16px 50px rgba(42, 37, 32, 0.15);
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-spring: 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--white);
  color: var(--charcoal);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

h1, h2, h3, h4 {
  font-family: 'Playfair Display', Georgia, serif;
  line-height: 1.2;
  color: var(--ink);
}

a { color: var(--accent-warm); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--accent-copper); }

img { max-width: 100%; height: auto; }

/* === Layout === */
.container { max-width: 1200px; margin: 0 auto; padding: 0 2rem; }
.container-narrow { max-width: 800px; margin: 0 auto; padding: 0 2rem; }

/* === Navigation === */
.nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--warm-gray-100);
  transition: var(--transition);
}
.nav.scrolled {
  box-shadow: var(--shadow-md);
}
.nav-inner {
  display: flex; align-items: center; justify-content: space-between;
  max-width: 1200px; margin: 0 auto; padding: 0.75rem 2rem;
}
.nav-logo {
  display: flex; align-items: center; gap: 0.75rem;
  font-family: 'Playfair Display', serif; font-size: 1.25rem;
  font-weight: 700; color: var(--ink);
}
.nav-logo img { height: 36px; width: 36px; object-fit: contain; }
.nav-links { display: flex; gap: 2rem; align-items: center; }
.nav-links a {
  font-size: 0.875rem; font-weight: 500; color: var(--warm-gray-600);
  letter-spacing: 0.02em; position: relative;
}
.nav-links a::after {
  content: ''; position: absolute; bottom: -4px; left: 0; width: 0;
  height: 2px; background: var(--accent-copper); transition: width var(--transition);
}
.nav-links a:hover { color: var(--ink); }
.nav-links a:hover::after { width: 100%; }

/* === Hero Section === */
.hero {
  padding: 10rem 2rem 6rem;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; inset: 0;
  background: radial-gradient(ellipse at center, transparent 40%, var(--white) 75%);
  z-index: 1;
}
.hero-content { position: relative; z-index: 2; }
.hero-logo {
  width: 140px; height: 140px;
  margin: 0 auto 2rem;
  animation: fadeInScale 1s ease-out;
  filter: drop-shadow(0 4px 12px rgba(42, 37, 32, 0.1));
}
@keyframes fadeInScale {
  from { opacity: 0; transform: scale(0.8) translateY(20px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}
.hero h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  margin-bottom: 1rem;
  animation: fadeInUp 1s ease-out 0.2s both;
}
.hero-tagline {
  font-size: 1.25rem; color: var(--warm-gray-600);
  max-width: 600px; margin: 0 auto 3rem;
  animation: fadeInUp 1s ease-out 0.4s both;
}
@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

/* === Search === */
.search-section {
  max-width: 640px; margin: 0 auto 4rem;
  animation: fadeInUp 1s ease-out 0.6s both;
}
.search-box {
  position: relative;
  display: flex; align-items: center;
  background: var(--white);
  border: 2px solid var(--warm-gray-200);
  border-radius: var(--radius-xl);
  padding: 0.25rem;
  transition: var(--transition);
  box-shadow: var(--shadow-sm);
}
.search-box:focus-within {
  border-color: var(--accent-copper);
  box-shadow: var(--shadow-md), 0 0 0 4px rgba(184, 115, 51, 0.1);
}
.search-icon {
  padding: 0 0.75rem 0 1.25rem;
  color: var(--warm-gray-400);
  display: flex; align-items: center;
}
.search-input {
  flex: 1; border: none; outline: none;
  font-size: 1rem; font-family: inherit;
  padding: 0.875rem 0.5rem; background: transparent;
  color: var(--charcoal);
}
.search-input::placeholder { color: var(--warm-gray-400); }

/* === Filter Tags === */
.filter-tags {
  display: flex; flex-wrap: wrap; gap: 0.5rem;
  justify-content: center; margin-bottom: 3rem;
  animation: fadeInUp 1s ease-out 0.8s both;
}
.filter-tag {
  padding: 0.5rem 1.25rem;
  border: 1.5px solid var(--warm-gray-200);
  border-radius: 999px;
  font-size: 0.8125rem; font-weight: 500;
  color: var(--warm-gray-600);
  cursor: pointer;
  transition: var(--transition);
  background: var(--white);
}
.filter-tag:hover {
  border-color: var(--accent-copper); color: var(--accent-copper);
  transform: translateY(-1px);
}
.filter-tag.active {
  background: var(--charcoal); color: var(--white);
  border-color: var(--charcoal);
}

/* === Topic Cards Grid === */
.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
  gap: 2rem; margin-bottom: 6rem;
}
.topic-card {
  background: var(--white);
  border: 1px solid var(--warm-gray-100);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: var(--transition);
  cursor: pointer;
  position: relative;
}
.topic-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--warm-gray-200);
}
.topic-card-image {
  width: 100%; height: 220px;
  object-fit: cover;
  border-bottom: 1px solid var(--warm-gray-100);
}
.topic-card-body { padding: 1.75rem; }
.topic-card-category {
  display: inline-block;
  font-size: 0.6875rem; font-weight: 600;
  letter-spacing: 0.08em; text-transform: uppercase;
  color: var(--accent-copper);
  margin-bottom: 0.75rem;
}
.topic-card h3 {
  font-size: 1.375rem; margin-bottom: 0.75rem;
  transition: color var(--transition);
}
.topic-card:hover h3 { color: var(--accent-copper); }
.topic-card p {
  font-size: 0.9rem; color: var(--warm-gray-600);
  line-height: 1.6; margin-bottom: 1.25rem;
}
.topic-card-meta {
  display: flex; gap: 1rem; flex-wrap: wrap;
}
.topic-card-tag {
  font-size: 0.75rem; font-weight: 500;
  color: var(--warm-gray-400);
  background: var(--warm-gray-50);
  padding: 0.25rem 0.75rem;
  border-radius: 999px;
}

/* === Sub-site / Topic Detail Page === */
.topic-hero {
  padding: 9rem 2rem 4rem;
  text-align: center;
  background: linear-gradient(180deg, var(--warm-gray-50) 0%, var(--white) 100%);
}
.topic-hero h1 {
  font-size: clamp(2rem, 4vw, 3.25rem);
  margin-bottom: 1rem;
}
.topic-hero-desc {
  font-size: 1.125rem; color: var(--warm-gray-600);
  max-width: 700px; margin: 0 auto;
}

/* === Essay Content === */
.essay-section { padding: 4rem 0; }
.essay-content h2, .essay-content h3 {
  margin: 2.5rem 0 1rem;
}
.essay-content h2 { font-size: 1.75rem; }
.essay-content h3 { font-size: 1.375rem; }
.essay-content p {
  font-size: 1.0625rem; line-height: 1.85;
  color: var(--warm-gray-800); margin-bottom: 1.5rem;
}
.essay-content ol, .essay-content ul {
  margin: 1rem 0 1.5rem 1.5rem;
  color: var(--warm-gray-800);
}
.essay-content li {
  margin-bottom: 0.5rem; line-height: 1.7;
}
.essay-content strong { color: var(--ink); }
.essay-content em { color: var(--accent-warm); font-style: italic; }

/* Inline illustration break */
.illustration-break {
  margin: 3rem auto;
  text-align: center;
  max-width: 400px;
}
.illustration-break img {
  width: 100%;
  border-radius: var(--radius-md);
  opacity: 0.9;
  transition: opacity var(--transition);
}
.illustration-break img:hover { opacity: 1; }

/* === Media Players === */
.media-section {
  padding: 3rem 0;
  border-top: 1px solid var(--warm-gray-100);
}
.media-section h2 { margin-bottom: 2rem; }
.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}
.media-card {
  background: var(--warm-gray-50);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--warm-gray-100);
}
.media-card audio, .media-card video {
  width: 100%; display: block;
}
.media-card-info {
  padding: 1rem 1.25rem;
}
.media-card-title {
  font-size: 0.875rem; font-weight: 600; color: var(--ink);
  margin-bottom: 0.25rem;
}
.media-card-type {
  font-size: 0.75rem; color: var(--warm-gray-400);
  text-transform: uppercase; letter-spacing: 0.05em;
}

/* === Interactive Quiz === */
.quiz-section { padding: 4rem 0; }
.quiz-section h2 { margin-bottom: 0.5rem; }
.quiz-subtitle {
  color: var(--warm-gray-600); margin-bottom: 2rem; font-size: 0.95rem;
}
.quiz-question {
  background: var(--warm-gray-50);
  border: 1px solid var(--warm-gray-100);
  border-radius: var(--radius-md);
  padding: 2rem;
  margin-bottom: 1.5rem;
  transition: var(--transition);
}
.quiz-question-text {
  font-family: 'Playfair Display', serif;
  font-size: 1.125rem; margin-bottom: 1.25rem; color: var(--ink);
  line-height: 1.5;
}
.quiz-question-number {
  font-size: 0.75rem; font-weight: 600; color: var(--accent-copper);
  text-transform: uppercase; letter-spacing: 0.06em;
  margin-bottom: 0.5rem;
}
.quiz-options { display: flex; flex-direction: column; gap: 0.625rem; }
.quiz-option {
  display: flex; align-items: center; gap: 0.75rem;
  padding: 0.875rem 1.25rem;
  border: 1.5px solid var(--warm-gray-200);
  border-radius: var(--radius-sm);
  cursor: pointer; font-size: 0.9375rem;
  transition: var(--transition);
  background: var(--white);
}
.quiz-option:hover {
  border-color: var(--accent-copper);
  background: rgba(184, 115, 51, 0.03);
}
.quiz-option.selected { border-color: var(--accent-copper); background: rgba(184, 115, 51, 0.06); }
.quiz-option.correct {
  border-color: var(--accent-sage); background: rgba(122, 139, 111, 0.08);
  color: #3d5a31;
}
.quiz-option.incorrect {
  border-color: #c44; background: rgba(204, 68, 68, 0.05);
  color: #993333; opacity: 0.7;
}
.quiz-option-letter {
  width: 28px; height: 28px;
  border-radius: 50%;
  background: var(--warm-gray-100);
  display: flex; align-items: center; justify-content: center;
  font-size: 0.75rem; font-weight: 600; color: var(--warm-gray-600);
  flex-shrink: 0;
}
.quiz-option.correct .quiz-option-letter { background: var(--accent-sage); color: white; }
.quiz-option.incorrect .quiz-option-letter { background: #c44; color: white; }
.quiz-feedback {
  margin-top: 0.75rem;
  padding: 0.75rem 1rem;
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  line-height: 1.5;
  display: none;
}
.quiz-feedback.show { display: block; }
.quiz-feedback.correct-feedback {
  background: rgba(122, 139, 111, 0.1);
  color: #3d5a31;
  border-left: 3px solid var(--accent-sage);
}
.quiz-feedback.incorrect-feedback {
  background: rgba(204, 68, 68, 0.06);
  color: #993333;
  border-left: 3px solid #c44;
}
.quiz-score {
  text-align: center; padding: 2rem;
  background: var(--warm-gray-50);
  border-radius: var(--radius-md);
  margin-top: 2rem;
  display: none;
}
.quiz-score.show { display: block; }
.quiz-score-number {
  font-family: 'Playfair Display', serif;
  font-size: 3rem; font-weight: 700; color: var(--accent-copper);
}
.quiz-score-label {
  font-size: 0.875rem; color: var(--warm-gray-600);
  margin-top: 0.5rem;
}

/* === Flashcards === */
.flashcards-section { padding: 4rem 0; }
.flashcards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.25rem;
}
.flashcard {
  perspective: 1000px;
  height: 220px; cursor: pointer;
}
.flashcard-inner {
  position: relative; width: 100%; height: 100%;
  transition: transform 0.6s cubic-bezier(0.4, 0, 0.2, 1);
  transform-style: preserve-3d;
}
.flashcard.flipped .flashcard-inner { transform: rotateY(180deg); }
.flashcard-front, .flashcard-back {
  position: absolute; inset: 0;
  backface-visibility: hidden;
  border-radius: var(--radius-md);
  padding: 1.5rem;
  display: flex; flex-direction: column;
  justify-content: center; align-items: center;
  text-align: center;
  border: 1px solid var(--warm-gray-100);
}
.flashcard-front {
  background: var(--warm-gray-50);
  font-family: 'Playfair Display', serif;
  font-size: 1rem; color: var(--ink); line-height: 1.5;
}
.flashcard-back {
  background: var(--charcoal); color: var(--white);
  transform: rotateY(180deg);
  font-size: 0.875rem; line-height: 1.6;
}
.flashcard-hint {
  font-size: 0.6875rem; color: var(--warm-gray-400);
  margin-top: 0.75rem;
  font-style: italic;
}

/* === Infographic === */
.infographic-section { padding: 4rem 0; text-align: center; }
.infographic-section img {
  max-width: 100%;
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-lg);
}

/* === Footer === */
.footer {
  padding: 4rem 2rem;
  border-top: 1px solid var(--warm-gray-100);
  text-align: center;
  color: var(--warm-gray-400);
  font-size: 0.8125rem;
}
.footer-logo { width: 48px; margin-bottom: 1rem; opacity: 0.6; }
.footer a { color: var(--warm-gray-600); }

/* === Responsive === */
@media (max-width: 768px) {
  .hero { padding: 8rem 1.5rem 4rem; }
  .topics-grid { grid-template-columns: 1fr; }
  .nav-links { display: none; }
  .container, .container-narrow { padding: 0 1.25rem; }
  .quiz-question { padding: 1.25rem; }
  .flashcards-grid { grid-template-columns: 1fr; }
}

/* === Utility Animations === */
.fade-in {
  opacity: 0; transform: translateY(16px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* === Section Divider === */
.section-divider {
  width: 60px; height: 2px;
  background: var(--warm-gray-200);
  margin: 3rem auto;
}

/* Back to top */
.back-to-top {
  position: fixed; bottom: 2rem; right: 2rem;
  width: 44px; height: 44px;
  border-radius: 50%;
  background: var(--charcoal); color: var(--white);
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden;
  transition: var(--transition);
  cursor: pointer; z-index: 99;
  box-shadow: var(--shadow-md);
  border: none; font-size: 1.25rem;
}
.back-to-top.show { opacity: 1; visibility: visible; }
.back-to-top:hover { transform: translateY(-2px); box-shadow: var(--shadow-lg); }