/* Reset & Global */
* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: 'Inter', system-ui, sans-serif;
  background-color: #F8FAFC;
  color: #0F172A;
  -webkit-font-smoothing: antialiased;
}

/* Base Layout & Containers */
.app-header-inner,
.main-container {
  max-width: 1100px;
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
}

.main-container {
  padding-top: 3rem;
  padding-bottom: 4rem;
}

/* Grids */
.grid-2-col,
.summary-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

@media (min-width: 768px) {
  .grid-2-col,
  .summary-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.stats-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.25rem;
  margin-bottom: 3rem;
}

@media (min-width: 768px) {
  .stats-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

.class-names-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
}

@media (min-width: 768px) {
  .class-names-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 2rem;
}

@media (min-width: 768px) {
  .footer-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

/* Flexbox Containers */
.header-content,
.section-header-flex,
.actions-footer {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.logo-container,
.section-title,
.verification-header,
.verification-item,
.warning-header,
.flex-center-gap,
.section-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.info-banner {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  padding: 1.5rem;
  margin-top: 3rem;
  border-radius: 12px;
  background-color: #F1F5F9;
  border: 1px solid #E2E8F0;
}

.error-banner {
  display: flex;
  gap: 0.75rem;
  padding: 1rem 1.25rem;
  margin-top: 1rem;
  border-radius: 8px;
}

.flex-end {
  display: flex;
  justify-content: flex-end;
}

.tabs-container {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin-bottom: 0;
  border-bottom: 2px solid #E2E8F0;
}

.config-row {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 2rem;
}

/* Cards & Panels (The "Glass" feeling for Light Mode) */
.glass-panel {
  background: #FFFFFF;
  border: 1px solid rgba(99, 102, 241, 0.08);
  border-radius: 16px;
  box-shadow: 0 10px 30px -5px rgba(0, 0, 0, 0.02), 0 8px 15px -6px rgba(0, 0, 0, 0.02);
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

.glass-panel:hover {
  transform: translateY(-3px);
  box-shadow: 0 20px 40px -15px rgba(99, 102, 241, 0.08);
  border-color: rgba(99, 102, 241, 0.2);
}

.upload-card {
  padding: 2.5rem 2rem;
  text-align: left;
}

.summary-card,
.config-card {
  padding: 2rem;
  margin-bottom: 3rem;
}

.stat-card {
  padding: 1.5rem;
}

/* Modern EdTech Typography styling */
.font-display {
  font-family: 'Outfit', sans-serif;
}

.text-gradient {
  background: linear-gradient(135deg, #6366F1 0%, #4F46E5 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Buttons */
.btn-primary-large {
  background: linear-gradient(135deg, #6366F1 0%, #4F46E5 100%);
  color: #FFFFFF !important;
  transition: all 0.2s ease;
  border: none;
  font-weight: 600;
  box-shadow: 0 4px 14px rgba(99, 102, 241, 0.35);
  padding: 0.875rem 1.75rem;
  border-radius: 12px;
  cursor: pointer;
}

.btn-primary-large:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(99, 102, 241, 0.5);
  background: linear-gradient(135deg, #4F46E5 0%, #4338CA 100%);
}

.tab-button {
  padding: 0.75rem 1.25rem;
  font-size: 0.875rem;
  font-weight: 600;
  background: transparent;
  border: none;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  color: #64748B;
  transition: all 0.2s ease;
}

.tab-button:hover {
  color: #4F46E5;
}

.num-input {
  width: 4.5rem;
  text-align: center;
  padding: 0.5rem;
  border-radius: 8px;
  font-size: 1.125rem;
  font-weight: 600;
  border: 1px solid #CBD5E1;
  background-color: #F8FAFC;
  color: #0F172A;
}

.num-input:focus {
  outline: none;
  border-color: #6366F1;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

/* Forms & Inputs */
input[type="text"] {
  border: 1px solid #E2E8F0;
  background-color: #F8FAFC;
  padding: 0.625rem 1rem;
  border-radius: 8px;
  color: #0F172A;
  transition: all 0.2s ease;
}

input[type="text"]:focus {
  outline: none;
  border-color: #6366F1;
  background-color: #FFFFFF;
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.15);
}

/* Privacy Badge */
.privacy-badge {
  display: none;
}

@media (min-width: 768px) {
  .privacy-badge {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 0.875rem;
    border-radius: 20px;
    font-size: 0.75rem;
    white-space: nowrap;
    background-color: #EEF2FF;
    color: #4F46E5;
    border: 1px solid rgba(99, 102, 241, 0.15);
    font-weight: 500;
  }
}

/* Tables & Lists */
.table-container {
  overflow-x: auto;
  border: 1px solid #E2E8F0;
  border-radius: 12px;
}

.table-scroll {
  overflow-x: auto;
  max-height: 500px;
  border-radius: 0 0 12px 12px;
}

.data-table {
  width: 100%;
  text-align: left;
  border-collapse: collapse;
  background-color: #FFFFFF;
}

.data-table th {
  background-color: #F8FAFC;
  color: #475569;
  font-weight: 600;
  text-transform: uppercase;
  font-size: 0.75rem;
  letter-spacing: 0.05em;
  border-bottom: 1px solid #E2E8F0;
  padding: 0.875rem 1rem;
}

.data-table td {
  padding: 0.875rem 1rem;
  border-bottom: 1px solid #F1F5F9;
  color: #334155;
}

.data-table tbody tr:hover {
  background-color: #FAF5FF;
}

/* Badges / Pills */
.pill {
  display: inline-flex;
  align-items: center;
  padding: 0.25rem 0.75rem;
  border-radius: 9999px;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

/* Spacing Helpers */
.mb-3 { margin-bottom: 0.75rem; }
.mb-6 { margin-bottom: 1.5rem; }
.mt-2 { margin-top: 0.5rem; }
.mt-4 { margin-top: 1rem; }

.app-footer {
  margin-top: 8rem;
  padding-top: 3rem;
  border-top: 1px solid #E2E8F0;
}

.hidden { display: none; }
@media (min-width: 768px) {
  .md\\:flex { display: flex; }
}

/* Utility Helper Classes */
.flex { display: flex; }
.items-center { align-items: center; }
.justify-center { justify-content: center; }
.text-sm { font-size: 0.875rem; }
.text-xs { font-size: 0.75rem; }
.w-8 { width: 2rem; }
.h-8 { height: 2rem; }
.rounded-md { border-radius: 6px; }
.px-3 { padding-left: 0.75rem; padding-right: 0.75rem; }
.py-2 { padding-top: 0.5rem; padding-bottom: 0.5rem; }
.py-1\\.5 { padding-top: 0.375rem; padding-bottom: 0.375rem; }
.gap-1\\.5 { gap: 0.375rem; }
.gap-2 { gap: 0.5rem; }
.cursor-pointer { cursor: pointer; }
.font-medium { font-weight: 500; }
.flex-wrap { flex-wrap: wrap; }
.border-b { border-bottom: 1px solid #E2E8F0; }
.text-left { text-align: left; }
.text-center { text-align: center; }
.w-full { width: 100%; }

/* Custom enhancements for the Modern EdTech theme */
.app-header {
  border-bottom: 1px solid #E2E8F0;
  background-color: #FFFFFF;
}
.header-tagline {
  margin-top: 1rem;
  max-width: 36rem;
  font-size: 1.125rem;
  color: #475569;
  line-height: 1.6;
}
.section-intro-text {
  font-size: 1rem;
  color: #64748B;
  margin-top: 0.25rem;
  margin-bottom: 1.5rem;
}
.btn-secondary {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border-radius: 8px;
  border: 1px solid #CBD5E1;
  background-color: #FFFFFF;
  color: #334155;
  font-weight: 500;
  font-size: 0.875rem;
  cursor: pointer;
  transition: all 0.2s ease;
}
.btn-secondary:hover {
  background-color: #F8FAFC;
  border-color: #94A3B8;
  color: #0F172A;
}