/* ==========================================================================
   FULL PRACTICE PAPERS - LANDING PAGE STYLES
   Premium mobile-first exam paper selection interface
   ========================================================================== */

/* PAGE HEADER */
.page-header {
  background: linear-gradient(135deg, #F0F4FF 0%, #FFFFFF 100%);
  padding: var(--space-2xl) 0;
  text-align: center;
  border-bottom: 1px solid var(--color-border);
}

.page-title {
  font-size: var(--text-3xl);
  color: var(--color-text-primary);
  margin-bottom: var(--space-sm);
}

.page-subtitle {
  font-size: var(--text-lg);
  color: var(--color-text-secondary);
  margin-bottom: var(--space-xl);
  max-width: 600px;
  margin-left: auto;
  margin-right: auto;
}

/* EXAM PLAN */
.exam-plan {
  background: white;
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  margin-top: var(--space-xl);
  max-width: 800px;
  margin-left: auto;
  margin-right: auto;
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
}

.plan-title {
  font-size: var(--text-xl);
  color: var(--color-text-primary);
  margin-bottom: var(--space-lg);
  text-align: center;
}

.plan-steps {
  display: flex;
  flex-direction: column;
  gap: var(--space-md);
}

.plan-step {
  display: flex;
  align-items: center;
  gap: var(--space-md);
  padding: var(--space-md);
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
}

.step-number {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  background: var(--color-primary);
  color: white;
  border-radius: var(--radius-full);
  font-weight: var(--font-weight-bold);
  font-size: var(--text-sm);
  flex-shrink: 0;
}

.step-text {
  font-size: var(--text-base);
  color: var(--color-text-primary);
  line-height: 1.5;
}

/* TIER TABS */
.tier-tabs {
  background: white;
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: var(--header-height);
  z-index: 100;
}

.tabs-wrapper {
  display: flex;
  gap: var(--space-sm);
  overflow-x: auto;
  padding: var(--space-md) 0;
  -webkit-overflow-scrolling: touch;
}

.tab-button {
  flex: 1;
  min-width: 150px;
  padding: var(--space-md) var(--space-lg);
  font-size: var(--text-base);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-secondary);
  background: transparent;
  border: 2px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: border-color var(--transition-button), 
              color var(--transition-button),
              background-color var(--transition-button),
              transform var(--transition-button),
              box-shadow var(--transition-button);
  white-space: nowrap;
  will-change: transform;
}

.tab-button:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
  transform: translateY(-1px);
  box-shadow: 0 2px 8px rgba(79, 70, 229, 0.1);
}

.tab-button:active {
  transform: scale(0.98);
}

.tab-button:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.tab-button.active {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: white;
  box-shadow: 0 2px 8px rgba(79, 70, 229, 0.2);
}

/* TIER CONTENT */
.tier-content {
  padding: var(--space-2xl) 0;
}

.tier-content.hidden {
  display: none;
}

/* PAPERS GRID */
.papers-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
}

/* PAPER CARD */
.paper-card {
  background: white;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: all var(--transition-base);
  cursor: pointer;
  position: relative;
}

.paper-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--color-primary);
}

.paper-card.completed {
  border-color: var(--color-success);
  background: linear-gradient(to bottom, white, #f0fdf4);
}

.paper-card.completed::before {
  content: '✓';
  position: absolute;
  top: var(--space-md);
  right: var(--space-md);
  width: 36px;
  height: 36px;
  background: var(--color-success);
  color: white;
  border-radius: var(--radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: var(--text-xl);
  font-weight: var(--font-weight-bold);
}

/* PAPER HEADER */
.paper-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: var(--space-lg);
}

.paper-title-group {
  flex: 1;
}

.paper-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 48px;
  height: 48px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-primary-light));
  color: white;
  border-radius: var(--radius-md);
  font-size: var(--text-xl);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-sm);
}

.paper-title {
  font-size: var(--text-2xl);
  color: var(--color-text-primary);
  margin-bottom: var(--space-xs);
}

.paper-subtitle {
  font-size: var(--text-base);
  color: var(--color-text-secondary);
}

/* PAPER DETAILS */
.paper-details {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: var(--space-md);
  margin-bottom: var(--space-lg);
  padding: var(--space-md);
  background: var(--color-bg-secondary);
  border-radius: var(--radius-md);
}

.detail-item {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.detail-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-weight: var(--font-weight-semibold);
}

.detail-value {
  font-size: var(--text-base);
  color: var(--color-text-primary);
  font-weight: var(--font-weight-semibold);
}

/* PAPER STATS */
.paper-stats {
  margin-bottom: var(--space-lg);
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-md);
}

.stat-card {
  padding: var(--space-md);
  background: var(--color-bg-tertiary);
  border-radius: var(--radius-md);
  text-align: center;
}

.stat-label {
  font-size: var(--text-xs);
  color: var(--color-text-muted);
  margin-bottom: var(--space-xs);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

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

.stat-subtext {
  font-size: var(--text-xs);
  color: var(--color-text-secondary);
  margin-top: var(--space-xs);
}

/* PAPER ACTION */
.paper-action {
  display: flex;
  gap: var(--space-md);
}

.paper-action .btn {
  flex: 1;
  justify-content: center;
}

/* EMPTY STATE */
.empty-state {
  text-align: center;
  padding: var(--space-4xl) var(--space-xl);
}

.empty-icon {
  font-size: 4rem;
  margin-bottom: var(--space-lg);
}

.empty-title {
  font-size: var(--text-2xl);
  color: var(--color-text-primary);
  margin-bottom: var(--space-sm);
}

.empty-text {
  font-size: var(--text-base);
  color: var(--color-text-secondary);
  max-width: 400px;
  margin: 0 auto;
}

/* RESPONSIVE - TABLET */
@media (min-width: 768px) {
  .page-title {
    font-size: var(--text-4xl);
  }
  
  .page-subtitle {
    font-size: var(--text-xl);
  }
  
  .plan-steps {
    flex-direction: row;
    justify-content: space-between;
  }
  
  .plan-step {
    flex-direction: column;
    text-align: center;
    flex: 1;
  }
  
  .papers-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .paper-details {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* MOBILE FIX - Ensure content visibility */
@media (max-width: 480px) {
  /* Fix tab button text truncation */
  .tab-button {
    min-width: 0 !important;
    padding: 10px 12px !important;
    font-size: 13px !important;
    white-space: normal !important;
    line-height: 1.3 !important;
  }
  
  main {
    height: auto !important;
    min-height: auto !important;
    overflow: visible !important;
  }
  
  .tier-content {
    height: auto !important;
    max-height: none !important;
    overflow: visible !important;
    opacity: 1 !important;
    visibility: visible !important;
  }
  
  .tier-content.hidden {
    display: none !important;
  }
  
  /* Force foundation visible by default */
  .tier-content[data-tier="foundation"] {
    display: block !important;
  }
  
  .tier-content[data-tier="foundation"].hidden {
    display: none !important;
  }
  
  .papers-grid {
    height: auto !important;
    max-height: none !important;
    overflow: visible !important;
    display: grid !important;
    opacity: 1 !important;
    visibility: visible !important;
  }
  
  #foundation-papers,
  #higher-papers {
    min-height: 200px !important;
  }
  
  .paper-card {
    opacity: 1 !important;
    visibility: visible !important;
    display: block !important;
    position: relative !important;
  }
  
  .container {
    height: auto !important;
    overflow: visible !important;
  }
}

/* RESPONSIVE - DESKTOP */
@media (min-width: 1024px) {
  .page-title {
    font-size: var(--text-5xl);
  }
  
  .papers-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}