/* =========================================
   THEORY NOTES / ADVANCED DOMAINS STYLES
   Notes landing page = blue header
   Advanced Domains section = forced 3-column layout
   ========================================= */

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  color: #111827;
  background: #f3f4f6;
}

h1,
h2,
h3,
h4 {
  font-family: "Times New Roman", Georgia, serif;
  font-weight: 700;
}

/* ---- Theory Notes hero header ---- */

.notes-hero {
  text-align: center;
  padding: 3.5rem 2rem 3rem;
  background: linear-gradient(135deg, #1d4ed8, #2563eb);
  color: #ffffff;
}

.notes-hero h1 {
  margin: 0 0 0.5rem;
  font-size: 3.2rem;
  font-weight: 700;
  line-height: 1.15;
}

.notes-tagline {
  margin: 0 0 1.8rem;
  font-size: 1rem;
  opacity: 0.95;
  color: rgba(255, 255, 255, 0.95);
}

/* Optional alternate page hero variation */
.domain-a-hero {
  background: linear-gradient(135deg, #1d4ed8, #2563eb);
}

/* ---- Header pill navigation ---- */

.pill-nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 1rem;
}

.pill {
  display: inline-block;
  padding: 0.55rem 1.4rem;
  border-radius: 999px;
  border: 1px solid rgba(248, 250, 252, 0.55);
  background: transparent;
  color: #f9fafb;
  font-size: 0.95rem;
  font-weight: 600;
  text-decoration: none;
  transition: background-color 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}

.pill:hover {
  background-color: rgba(255, 255, 255, 0.12);
}

.pill.active {
  background-color: #ffffff;
  border-color: #ffffff;
  color: #1d4ed8;
}

/* ---- Core layout ---- */

.page-main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 3.5rem;
  font-size: 1.05rem;
  line-height: 1.6;
}

/* ---- Cards: intro, main notes, advanced domains ---- */

.notes-intro-card,
.notes-card,
.advanced-notes-card {
  background: #ffffff;
  border-radius: 20px;
  box-shadow: 0 18px 45px rgba(15, 23, 42, 0.06);
  border: 1px solid #e5e7eb;
}

.notes-intro-card {
  padding: 1.6rem 1.9rem;
  margin-bottom: 2rem;
}

.notes-card {
  padding: 1.8rem 1.9rem 1.6rem;
}

.advanced-notes-card {
  margin-top: 2rem;
  padding: 1.8rem 1.9rem 1.6rem;
}

.notes-intro-card h2,
.advanced-notes-card h2 {
  margin: 0 0 0.4rem;
}

.advanced-notes-card p {
  margin-top: 0;
  margin-bottom: 1rem;
  color: #4b5563;
}

/* ---- Two-column layout for core theory checklist ---- */

.notes-two-column {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: start;
}

.notes-two-column > div {
  min-width: 0;
}

/* ---- Green badges for section headings in Notes page ---- */

.notes-section-title {
  display: inline-block;
  margin-top: 1.6rem;
  margin-bottom: 0.6rem;
  padding: 0.25rem 0.8rem;
  border-radius: 999px;
  background: #bbf7d0;
  color: #065f46;
  font-size: 1.05rem;
  font-weight: 700;
}

.notes-two-column > div .notes-section-title:first-child {
  margin-top: 0;
}

/* ---- Topic list formatting ---- */

.notes-topic-list {
  margin: 0 0 1.2rem;
  padding-left: 1.1rem;
}

.notes-topic-list li {
  margin-bottom: 0.35rem;
  color: #374151;
  font-size: 0.97rem;
}

.notes-topic-list a {
  color: #1d4ed8;
  text-decoration: underline;
}

.notes-topic-list a:hover {
  color: #1e40af;
}

/* =========================================
   DOMAIN PAGES / GENERAL NOTES CONTENT
   ========================================= */

.breadcrumb {
  font-size: 0.95rem;
  margin: 0 0 0.6rem;
}

.breadcrumb a {
  color: #0c4a6e;
  text-decoration: none;
}

.breadcrumb a:hover {
  text-decoration: underline;
}

.notes-section {
  margin-top: 2rem;
}

.key-idea {
  background: #e9f8ee;
  border-left: 4px solid #39a36f;
  padding: 0.8rem 1rem;
  margin: 1rem 0;
  font-style: italic;
}

.subtopic-nav {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.95rem;
  margin: 1.2rem 0 0.6rem;
}

.subtopic-nav span {
  font-weight: 600;
}

.subtopic-nav a {
  color: #0c5cb6;
  text-decoration: none;
}

.subtopic-nav a:hover {
  text-decoration: underline;
}

pre {
  background: #f8f8f8;
  padding: 1rem;
  border-radius: 8px;
  border: 1px solid #e3e3e3;
  overflow-x: auto;
  margin: 0.8rem 0 1rem;
}

pre code {
  font-size: 1.05rem;
  line-height: 1.45;
}

.next-domain-links {
  margin-top: 2.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid #e5e7eb;
}

.next-domain-links h3 {
  margin-top: 0;
}

.next-domain-links ul {
  padding-left: 1.2rem;
}

.pill-link {
  display: inline-block;
  margin-top: 0.2rem;
  padding: 0.45rem 1.3rem;
  border-radius: 999px;
  background: #0c4a6e;
  color: #ffffff;
  text-decoration: none;
  font-size: 0.95rem;
  font-weight: 600;
}

.pill-link:hover {
  background: #075985;
}

/* =========================================
   ADVANCED DOMAINS GRID
   Forced 3 columns on desktop
   ========================================= */

.advanced-domains-grid {
  display: grid !important;
  grid-template-columns: repeat(3, minmax(0, 1fr)) !important;
  gap: 1.4rem !important;
}

.domain-card {
  display: block;
  min-width: 0;
  padding: 1.05rem 1.2rem;
  border-radius: 14px;
  border: 1px solid #d1fae5;
  background: #f0fdf4;
  text-decoration: none;
  transition: transform 0.1s ease, box-shadow 0.1s ease, background 0.1s ease;
}

.domain-card h3 {
  margin: 0 0 0.35rem;
  font-size: 1.15rem;
  color: #065f46;
}

.domain-card h3 a {
  color: #065f46;
  text-decoration: none;
}

.domain-card h3 a:hover {
  text-decoration: underline;
}

.domain-card p {
  margin: 0 0 0.15rem;
  font-size: 0.95rem;
  color: #047857;
}

.domain-meta {
  display: block;
  font-size: 0.85rem;
  color: #065f46;
}

.domain-card:hover {
  background: #dcfce7;
  box-shadow: 0 10px 25px rgba(22, 163, 74, 0.15);
  transform: translateY(-1px);
}

/* ---- Expanded cards with subtopics ---- */

.domain-a-expanded,
.domain-b-expanded,
.domain-c-expanded,
.domain-d-expanded,
.domain-e-expanded,
.domain-f-expanded {
  padding: 1.5rem;
  border-radius: 12px;
  background: #e8f7ee;
  border: 1px solid #c8e8d5;
}

.domain-subtopics {
  margin-top: 1rem;
  padding-left: 1.2rem;
}

.domain-subtopics li {
  margin-bottom: 0.45rem;
}

.domain-subtopics li a {
  color: #0d7d44;
  font-weight: 600;
  text-decoration: none;
}

.domain-subtopics li a:hover {
  text-decoration: underline;
}

.next-domain-link {
  margin-top: 1rem;
  font-size: 0.9rem;
}

.next-domain-link a {
  color: #0c5cb6;
  text-decoration: none;
  font-weight: 600;
}

.next-domain-link a:hover {
  text-decoration: underline;
}

/* ---- Footer ---- */

.site-footer {
  text-align: center;
  padding: 2rem 1.5rem 2.5rem;
  color: #4b5563;
  font-size: 0.95rem;
}

.site-footer p {
  margin: 0;
  max-width: 900px;
  margin-inline: auto;
}

/* ---- Responsive layout ---- */

@media (max-width: 1000px) {
  .advanced-domains-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr)) !important;
  }
}

@media (max-width: 768px) {
  .notes-hero {
    padding: 3rem 1.2rem 2.5rem;
  }

  .notes-hero h1 {
    font-size: 2.4rem;
  }

  .page-main {
    padding: 2rem 1rem 3rem;
  }

  .notes-intro-card,
  .notes-card,
  .advanced-notes-card {
    padding-left: 1.2rem;
    padding-right: 1.2rem;
  }

  .notes-two-column {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }

  .advanced-domains-grid {
    grid-template-columns: 1fr !important;
  }
}