/* ===== Landing Page ===== */

.hero {
  padding: var(--space-4xl) 0;
  color: white;
  text-align: center;
  margin-top: calc(-1 * var(--header-height));
  padding-top: calc(var(--header-height) + var(--space-4xl));
  min-height: 520px;
  display: flex;
  align-items: center;
}

.hero > .container {
  width: 100%;
}

.hero h1 {
  color: white;
  font-size: var(--text-5xl);
  margin-bottom: var(--space-md);
  position: relative;
  letter-spacing: -0.02em;
}

.hero p {
  color: rgba(255, 255, 255, 0.85);
  font-size: var(--text-xl);
  max-width: 600px;
  margin: 0 auto var(--space-xl);
  position: relative;
}

.hero .btn-primary {
  background: white;
  color: var(--color-primary);
  font-size: var(--text-base);
  padding: 0.875rem 2rem;
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.15);
}

.hero .btn-primary:hover {
  background: rgba(255,255,255,0.95);
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.2);
}

.hero .btn-secondary {
  border-color: rgba(255,255,255,0.5);
  color: white;
}

.hero .btn-secondary:hover {
  background: rgba(255,255,255,0.1);
  border-color: white;
}

.hero-buttons {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
}

/* Hero sub-elements */
.hero__background {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero__content {
  position: relative;
  z-index: 1;
  width: 100%;
}

.hero__actions {
  display: flex;
  gap: var(--space-md);
  justify-content: center;
  flex-wrap: wrap;
  position: relative;
}

.hero__actions .btn-secondary {
  color: white;
  border-color: white;
}

.hero__actions .btn-secondary:hover {
  background: rgba(255, 255, 255, 0.15);
  color: white;
}

/* Exam Categories */
.categories {
  padding: var(--space-3xl) 0;
}

.category {
  margin-bottom: var(--space-2xl);
}

.category__title {
  margin-bottom: var(--space-xl);
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--space-lg);
}

/* Stats bar */
.stats-bar {
  background: var(--color-surface);
  border-bottom: 1px solid var(--color-border);
  padding: var(--space-xl) 0;
}

.stats-bar__inner {
  display: flex;
  justify-content: center;
  gap: var(--space-3xl);
  flex-wrap: wrap;
}

/* Category Section */
.category-section {
  padding: var(--space-3xl) 0;
}

.category-header {
  text-align: center;
  margin-bottom: var(--space-2xl);
}

.category-header p {
  max-width: 600px;
  margin: 0 auto;
}

/* Exam Cards on Landing */
.exam-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-xl);
  display: flex;
  flex-direction: column;
  transition: all var(--transition-base);
}

.exam-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.exam-card__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-md);
}

.exam-card__series {
  font-size: var(--text-2xl);
  font-weight: var(--weight-bold);
  color: var(--color-primary);
}

.exam-card__name {
  font-size: var(--text-base);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-sm);
}

.exam-card__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  flex: 1;
  margin-bottom: var(--space-md);
}

.exam-card__meta {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-bottom: var(--space-md);
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

.exam-card__meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

/* How it works */
.how-it-works {
  background: var(--color-surface);
  padding: var(--space-3xl) 0;
}

.steps {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-2xl);
  counter-reset: step;
}

.step {
  text-align: center;
  position: relative;
}

.step__number {
  width: 56px;
  height: 56px;
  background: var(--gradient-primary);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  font-weight: var(--weight-bold);
  margin: 0 auto var(--space-md);
  box-shadow: var(--shadow-colored-primary);
}

.step__title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-sm);
}

.step__desc {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

@media (max-width: 768px) {
  .steps {
    grid-template-columns: 1fr;
    gap: var(--space-xl);
  }

  .hero {
    min-height: auto;
    padding: var(--space-2xl) 0;
    padding-top: calc(var(--header-height) + var(--space-2xl));
  }

  .stats-bar__inner {
    gap: var(--space-xl);
  }

  .exam-card:hover {
    transform: none;
  }

  .exam-card:active {
    box-shadow: var(--shadow-md);
  }

  .dashboard-stats .stat {
    padding: var(--space-md);
  }
}

/* ===== Exam Catalog ===== */

.catalog-header {
  padding: var(--space-2xl) 0;
  text-align: center;
}

.catalog-filters {
  display: flex;
  justify-content: center;
  gap: var(--space-sm);
  margin-bottom: var(--space-xl);
  flex-wrap: wrap;
}

.filter-btn {
  padding: var(--space-sm) var(--space-lg);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-full);
  background: transparent;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  color: var(--color-text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.filter-btn:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.filter-btn.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
}

.catalog-search {
  max-width: 400px;
  margin: 0 auto var(--space-xl);
  position: relative;
}

.catalog-search input {
  width: 100%;
  padding: 0.75rem var(--space-lg) 0.75rem 2.75rem;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-full);
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  transition: border-color var(--transition-fast);
}

.catalog-search input:focus {
  outline: none;
  border-color: var(--color-primary);
}

.catalog-search__icon {
  position: absolute;
  left: var(--space-md);
  top: 50%;
  transform: translateY(-50%);
  color: var(--color-text-muted);
}

/* ===== Individual Exam Page ===== */

.exam-hero {
  padding: var(--space-2xl) 0;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--space-2xl);
}

.exam-hero__badge {
  display: inline-block;
  margin-bottom: var(--space-md);
}

.exam-hero__series {
  font-size: var(--text-5xl);
  font-weight: var(--weight-bold);
  color: var(--color-primary);
  margin-bottom: var(--space-xs);
}

.exam-hero__title {
  font-size: var(--text-2xl);
  margin-bottom: var(--space-md);
}

.exam-hero__purpose {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  max-width: 700px;
}

/* Topic section */
.topic-section {
  margin-bottom: var(--space-lg);
}

.topic-header {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  margin-bottom: var(--space-md);
}

.topic-title {
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
}

.topic-weight {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.subtopic-list {
  list-style: none;
  padding: 0;
}

.subtopic-item {
  display: flex;
  align-items: flex-start;
  gap: var(--space-sm);
  padding: var(--space-sm) 0;
  border-bottom: 1px solid var(--color-border-light);
  color: var(--color-text-secondary);
  font-size: var(--text-sm);
}

.subtopic-item:last-child {
  border-bottom: none;
}

/* Concept card */
.concept-card {
  background: var(--color-primary-bg);
  border: 1px solid transparent;
  border-radius: var(--radius-lg);
  padding: var(--space-md) var(--space-lg);
  margin-bottom: var(--space-sm);
  cursor: pointer;
  transition: all var(--transition-fast);
}

.concept-card:hover {
  border-color: var(--color-primary);
}

.concept-card__title {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--color-primary);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.concept-card__body {
  display: none;
  margin-top: var(--space-md);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
  line-height: var(--leading-relaxed);
}

.concept-card.expanded .concept-card__body {
  display: block;
  animation: fadeSlideUp 0.3s ease;
}

.concept-card .keyword {
  background: rgba(26, 86, 219, 0.1);
  color: var(--color-primary);
  padding: 0.1em 0.3em;
  border-radius: var(--radius-sm);
  font-weight: var(--weight-medium);
}

/* Donut chart container */
.donut-chart-container {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xl);
  padding: var(--space-xl) 0;
}

.donut-chart {
  width: 200px;
  height: 200px;
}

.donut-legend {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
}

.donut-legend__item {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: var(--text-sm);
  color: var(--color-text-secondary);
}

.donut-legend__color {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  flex-shrink: 0;
}

@media (max-width: 640px) {
  .donut-chart-container {
    flex-direction: column;
  }
}

/* ===== Pathway Page ===== */

.pathway-container {
  padding: var(--space-2xl) 0;
}

.pathway-diagram {
  position: relative;
  min-height: 600px;
  overflow-x: auto;
}

.pathway-node {
  position: absolute;
  background: var(--color-surface);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-md) var(--space-lg);
  text-align: center;
  cursor: pointer;
  transition: all var(--transition-base);
  z-index: 1;
  min-width: 120px;
}

.pathway-node:hover {
  transform: scale(1.05);
  box-shadow: var(--shadow-lg);
  z-index: 2;
}

.pathway-node.entry { border-color: var(--color-entry); }
.pathway-node.representative { border-color: var(--color-representative); }
.pathway-node.principal { border-color: var(--color-principal); }

.pathway-node.highlighted {
  box-shadow: 0 0 0 3px var(--color-primary), var(--shadow-lg);
}

.pathway-node__label {
  font-size: var(--text-sm);
  font-weight: var(--weight-bold);
}

.pathway-node__name {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

/* Career tracks */
.pathway-tracks {
  display: flex;
  gap: var(--space-md);
  flex-wrap: wrap;
  margin-bottom: var(--space-xl);
}

.track-btn {
  padding: var(--space-sm) var(--space-md);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-full);
  background: transparent;
  font-family: var(--font-sans);
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  cursor: pointer;
  transition: all var(--transition-fast);
  color: var(--color-text-secondary);
}

.track-btn:hover, .track-btn.active {
  border-color: var(--color-primary);
  color: var(--color-primary);
  background: var(--color-primary-bg);
}

/* ===== Progress Dashboard ===== */

.dashboard-header {
  padding: var(--space-2xl) 0;
  text-align: center;
}

.dashboard-stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-md);
  margin-bottom: var(--space-2xl);
}

.dashboard-stats .stat {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
}

/* Study streak heatmap */
.heatmap {
  margin: var(--space-xl) 0;
}

.heatmap__grid {
  display: grid;
  grid-template-columns: repeat(52, 1fr);
  gap: 3px;
}

.heatmap__cell {
  aspect-ratio: 1;
  border-radius: 2px;
  background: var(--color-border-light);
}

.heatmap__cell.level-1 { background: var(--color-accent-bg); }
.heatmap__cell.level-2 { background: #6ee7b7; }
.heatmap__cell.level-3 { background: var(--color-accent); }
.heatmap__cell.level-4 { background: var(--color-accent-dark); }

/* Exam progress grid */
.exam-progress-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: var(--space-lg);
}

.exam-progress-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-xl);
  padding: var(--space-lg);
  display: flex;
  align-items: center;
  gap: var(--space-md);
  transition: all var(--transition-base);
}

.exam-progress-card:hover {
  box-shadow: var(--shadow-md);
}

.exam-progress-card__ring {
  flex-shrink: 0;
}

.exam-progress-card__info {
  flex: 1;
  min-width: 0;
}

.exam-progress-card__title {
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  margin-bottom: var(--space-xs);
}

.exam-progress-card__meta {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
}

@media (max-width: 768px) {
  .dashboard-stats {
    grid-template-columns: repeat(2, 1fr);
  }

  .heatmap__grid {
    grid-template-columns: repeat(26, 1fr);
  }
}

/* ===== About Page ===== */

.about-section {
  padding: var(--space-2xl) 0;
}

.about-section h2 {
  margin-bottom: var(--space-md);
}

.disclaimer-box {
  background: var(--color-warning-bg);
  border: 1px solid var(--color-warning);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin-bottom: var(--space-xl);
}

.disclaimer-box p {
  color: var(--color-text);
  margin-bottom: 0;
}