/* ==========================================================================
   AI Smeta — Dark Theme Stylesheet
   Environmental monitoring cost estimator demo UI
   ========================================================================== */

/* --------------------------------------------------------------------------
   CSS Custom Properties
   -------------------------------------------------------------------------- */
:root {
  /* Backgrounds */
  --bg-primary: #0d1117;
  --bg-card: #161b21;
  --bg-header: #21262d;
  --bg-input: #0d1117;
  --bg-color: #0d1117;
  --card-bg: #161b21;

  /* Borders */
  --border-default: #30363d;
  --border-muted: #21262d;
  --border-color: #30363d;

  /* Accent colors */
  --accent-green: #70c360;
  --accent-green-hover: #5fb350;
  --accent-green-muted: rgba(112, 195, 96, 0.15);
  --accent-red: #f85149;
  --accent-red-muted: rgba(248, 81, 73, 0.15);
  --accent-amber: #d29922;
  --accent-amber-muted: rgba(210, 153, 34, 0.15);

  /* Primary / Secondary colors */
  --primary-color: #70c360;
  --secondary-color: #5fb350;

  /* Text */
  --text-primary: #e6edf3;
  --text-secondary: #8b949e;
  --text-muted: #484f58;

  /* Typography */
  --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Noto Sans',
    Helvetica, Arial, sans-serif;

  /* Radii */
  --radius-card: 8px;
  --radius-btn: 6px;
  --radius-sm: 4px;

  /* Shadows */
  --shadow-card: 0 1px 3px rgba(0, 0, 0, 0.3);
  --shadow-card-hover: 0 4px 12px rgba(0, 0, 0, 0.4);
  --shadow-btn: 0 1px 2px rgba(0, 0, 0, 0.2);

  /* Sizing */
  --max-width: 1200px;

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-family);
  background-color: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* --------------------------------------------------------------------------
   1. Layout
   -------------------------------------------------------------------------- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 24px;
}

header {
  padding: 32px 0 24px;
  border-bottom: 1px solid var(--border-default);
  margin-bottom: 32px;
}

header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  color: var(--text-primary);
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}

header h1 span {
  color: var(--accent-green);
}

header .subtitle {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  font-weight: 400;
}

/* --------------------------------------------------------------------------
   2. Tabs
   -------------------------------------------------------------------------- */
.tabs {
  display: flex;
  gap: 0;
  border-bottom: 1px solid var(--border-default);
  margin-bottom: 28px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
}

.tabs::-webkit-scrollbar {
  display: none;
}

.tab {
  position: relative;
  padding: 10px 20px;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  color: var(--text-secondary);
  font-family: var(--font-family);
  font-size: 0.9375rem;
  font-weight: 500;
  cursor: pointer;
  white-space: nowrap;
  transition: color var(--transition-fast), border-color var(--transition-fast);
}

.tab:hover {
  color: var(--text-primary);
}

.tab.active {
  color: var(--accent-green);
  border-bottom-color: var(--accent-green);
}

/* --------------------------------------------------------------------------
   3. Tab Content
   -------------------------------------------------------------------------- */
.tab-content {
  display: none;
}

.tab-content.active {
  display: block;
}

/* --------------------------------------------------------------------------
   4. Dropzone
   -------------------------------------------------------------------------- */
.dropzone {
  position: relative;
  min-height: 160px;
  border: 2px dashed var(--border-default);
  border-radius: var(--radius-card);
  background-color: var(--bg-card);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  padding: 32px 24px;
  cursor: pointer;
  transition: border-color var(--transition-normal),
    background-color var(--transition-normal);
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--accent-green);
  background-color: var(--accent-green-muted);
}

.dropzone .dropzone-icon {
  font-size: 2.5rem;
  color: var(--text-secondary);
  transition: color var(--transition-normal);
}

.dropzone:hover .dropzone-icon,
.dropzone.dragover .dropzone-icon {
  color: var(--accent-green);
}

.dropzone .dropzone-text {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  text-align: center;
}

.dropzone .dropzone-text strong {
  color: var(--accent-green);
}

.dropzone .dropzone-hint {
  font-size: 0.8125rem;
  color: var(--text-muted);
}

.dropzone input[type='file'] {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
}

/* --------------------------------------------------------------------------
   5. File Info
   -------------------------------------------------------------------------- */
.file-info {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background-color: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  margin-top: 12px;
}

.file-info .file-icon {
  font-size: 1.25rem;
  color: var(--accent-green);
  flex-shrink: 0;
}

.file-info .file-name {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-info .file-size {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin-left: auto;
  flex-shrink: 0;
}

.file-info .file-remove {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 1rem;
  padding: 4px;
  border-radius: var(--radius-sm);
  transition: color var(--transition-fast), background-color var(--transition-fast);
}

.file-info .file-remove:hover {
  color: var(--accent-red);
  background-color: var(--accent-red-muted);
}

/* --------------------------------------------------------------------------
   6. Buttons
   -------------------------------------------------------------------------- */
.btn-primary,
.btn-secondary,
.btn-download {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: var(--font-family);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-btn);
  cursor: pointer;
  transition: background-color var(--transition-fast),
    border-color var(--transition-fast), color var(--transition-fast),
    box-shadow var(--transition-fast), opacity var(--transition-fast);
  line-height: 1;
  white-space: nowrap;
}

/* Primary */
.btn-primary {
  padding: 10px 20px;
  background-color: var(--accent-green);
  color: #0d1117;
  border: 1px solid var(--accent-green);
  box-shadow: var(--shadow-btn);
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--accent-green-hover);
  border-color: var(--accent-green-hover);
}

.btn-primary:active:not(:disabled) {
  transform: translateY(1px);
}

/* Secondary (outline) */
.btn-secondary {
  padding: 10px 20px;
  background-color: transparent;
  color: var(--text-primary);
  border: 1px solid var(--border-default);
}

.btn-secondary:hover:not(:disabled) {
  background-color: var(--bg-card);
  border-color: var(--text-secondary);
}

.btn-secondary:active:not(:disabled) {
  transform: translateY(1px);
}

/* Download (larger accent) */
.btn-download {
  padding: 14px 28px;
  font-size: 1rem;
  background-color: var(--accent-green);
  color: #0d1117;
  border: 1px solid var(--accent-green);
  box-shadow: var(--shadow-btn);
}

.btn-download:hover:not(:disabled) {
  background-color: var(--accent-green-hover);
  border-color: var(--accent-green-hover);
}

.btn-download:active:not(:disabled) {
  transform: translateY(1px);
}

/* Disabled state — all buttons */
.btn-primary:disabled,
.btn-secondary:disabled,
.btn-download:disabled {
  opacity: 0.45;
  cursor: not-allowed;
  transform: none;
}

/* --------------------------------------------------------------------------
   7. Progress Steps
   -------------------------------------------------------------------------- */
.progress-steps {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  padding: 24px 0;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
}

.step {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  min-width: 100px;
  text-align: center;
  position: relative;
  flex: 1;
}

/* Connector line between steps */
.step:not(:last-child)::after {
  content: '';
  position: absolute;
  top: 16px;
  left: calc(50% + 20px);
  width: calc(100% - 40px);
  height: 2px;
  background-color: var(--border-default);
}

.step.done:not(:last-child)::after {
  background-color: var(--accent-green);
}

.step .step-icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.875rem;
  font-weight: 700;
  position: relative;
  z-index: 1;
  border: 2px solid var(--border-default);
  background-color: var(--bg-primary);
  color: var(--text-secondary);
  transition: all var(--transition-normal);
}

.step .step-label {
  font-size: 0.75rem;
  color: var(--text-secondary);
  font-weight: 500;
  line-height: 1.3;
}

/* Done */
.step.done .step-icon {
  background-color: var(--accent-green);
  border-color: var(--accent-green);
  color: #0d1117;
}

.step.done .step-label {
  color: var(--text-primary);
}

/* Active (pulsing) */
.step.active .step-icon {
  border-color: var(--accent-green);
  color: var(--accent-green);
  background-color: rgba(112, 195, 96, 0.15);
  animation: step-pulse 1.2s ease-in-out infinite;
}

.step.active .step-label {
  color: var(--accent-green);
  font-weight: 600;
}

@keyframes step-pulse {
  0% {
    box-shadow: 0 0 0 0 rgba(112, 195, 96, 0.7), 0 0 8px rgba(112, 195, 96, 0.5);
    transform: scale(1);
  }
  50% {
    box-shadow: 0 0 0 12px rgba(112, 195, 96, 0), 0 0 20px rgba(112, 195, 96, 0.3);
    transform: scale(1.08);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(112, 195, 96, 0.7), 0 0 8px rgba(112, 195, 96, 0.5);
    transform: scale(1);
  }
}

/* Pending (gray) */
.step.pending .step-icon {
  border-color: var(--border-default);
  color: var(--text-muted);
  background-color: var(--bg-primary);
}

.step.pending .step-label {
  color: var(--text-muted);
}

/* --------------------------------------------------------------------------
   8. Cost Cards
   -------------------------------------------------------------------------- */
.cost-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-bottom: 24px;
}

.cost-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  padding: 20px;
  box-shadow: var(--shadow-card);
  transition: box-shadow var(--transition-normal);
}

.cost-card:hover {
  box-shadow: var(--shadow-card-hover);
}

.cost-card .cost-label {
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 8px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.cost-card .cost-value {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
}

.cost-card .cost-unit {
  font-size: 0.8125rem;
  font-weight: 400;
  color: var(--text-secondary);
  margin-left: 4px;
}

/* Total card — accent left border */
.cost-card.total {
  border-left: 3px solid var(--accent-green);
}

.cost-card.total .cost-value {
  color: var(--accent-green);
}

/* --------------------------------------------------------------------------
   9. Stats Row
   -------------------------------------------------------------------------- */
.stats-row {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  padding: 16px 0;
}

.stats-row .stat-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.stats-row .stat-label {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  font-weight: 500;
}

.stats-row .stat-value {
  font-size: 1.125rem;
  color: var(--text-primary);
  font-weight: 700;
}

/* --------------------------------------------------------------------------
   10. Accuracy Section
   -------------------------------------------------------------------------- */
.accuracy-section {
  background-color: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  padding: 24px;
  margin-bottom: 24px;
  box-shadow: var(--shadow-card);
}

.accuracy-section .accuracy-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 16px;
}

.accuracy-section .accuracy-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
}

.accuracy-bar {
  width: 100%;
  height: 12px;
  background-color: var(--bg-primary);
  border-radius: 6px;
  overflow: hidden;
  position: relative;
}

.accuracy-bar .accuracy-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent-red), var(--accent-amber), var(--accent-green));
  border-radius: 6px;
  transition: width 0.6s ease;
}

.accuracy-bar .accuracy-fill[data-level='high'] {
  background: var(--accent-green);
}

.accuracy-bar .accuracy-fill[data-level='medium'] {
  background: var(--accent-amber);
}

.accuracy-bar .accuracy-fill[data-level='low'] {
  background: var(--accent-red);
}

.verdict-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 12px;
  font-size: 0.8125rem;
  font-weight: 600;
  border-radius: 20px;
  line-height: 1.5;
}

.verdict-badge.verdict-good {
  background-color: var(--accent-green-muted);
  color: var(--accent-green);
}

.verdict-badge.verdict-fair {
  background-color: var(--accent-amber-muted);
  color: var(--accent-amber);
}

.verdict-badge.verdict-poor {
  background-color: var(--accent-red-muted);
  color: var(--accent-red);
}

/* --------------------------------------------------------------------------
   11. Data Table
   -------------------------------------------------------------------------- */
.table-wrapper {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  margin-bottom: 24px;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.875rem;
  line-height: 1.5;
}

.data-table thead th {
  background-color: var(--bg-header);
  color: var(--text-secondary);
  font-weight: 600;
  text-align: left;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border-default);
  white-space: nowrap;
  font-size: 0.8125rem;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.data-table tbody td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--border-muted);
  color: var(--text-primary);
  vertical-align: middle;
}

/* Striped rows */
.data-table tbody tr:nth-child(odd) {
  background-color: var(--bg-card);
}

.data-table tbody tr:nth-child(even) {
  background-color: var(--bg-primary);
}

.data-table tbody tr:hover {
  background-color: rgba(112, 195, 96, 0.04);
}

.data-table tbody tr:last-child td {
  border-bottom: none;
}

/* Right-align numeric columns */
.data-table .col-number {
  text-align: right;
  font-variant-numeric: tabular-nums;
}

/* Delta column coloring */
.data-table .delta-positive {
  color: var(--accent-green);
  font-weight: 600;
}

.data-table .delta-negative {
  color: var(--accent-red);
  font-weight: 600;
}

.data-table .delta-neutral {
  color: var(--text-secondary);
}

/* --------------------------------------------------------------------------
   12. Compare Grid
   -------------------------------------------------------------------------- */
.compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-bottom: 24px;
}

/* --------------------------------------------------------------------------
   13. Summary Card (Compare)
   -------------------------------------------------------------------------- */
.summary-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.summary-card .summary-header {
  padding: 16px 20px;
  background-color: var(--bg-header);
  border-bottom: 1px solid var(--border-default);
}

.summary-card .summary-filename {
  font-size: 0.9375rem;
  font-weight: 600;
  color: var(--text-primary);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.summary-card .summary-meta {
  font-size: 0.8125rem;
  color: var(--text-secondary);
  margin-top: 2px;
}

.summary-card .summary-stats {
  padding: 16px 20px;
  list-style: none;
}

.summary-card .summary-stats li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 8px 0;
  border-bottom: 1px solid var(--border-muted);
  font-size: 0.875rem;
}

.summary-card .summary-stats li:last-child {
  border-bottom: none;
}

.summary-card .summary-stats .stat-key {
  color: var(--text-secondary);
}

.summary-card .summary-stats .stat-val {
  color: var(--text-primary);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

/* --------------------------------------------------------------------------
   14. Delta Card
   -------------------------------------------------------------------------- */
.delta-card {
  background-color: var(--bg-card);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-card);
  padding: 24px;
  box-shadow: var(--shadow-card);
  margin-bottom: 24px;
}

.delta-card .delta-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.delta-card .delta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--border-muted);
  font-size: 0.875rem;
}

.delta-card .delta-row:last-child {
  border-bottom: none;
}

.delta-card .delta-label {
  color: var(--text-secondary);
}

.delta-card .delta-value {
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}

.delta-card .delta-value.positive {
  color: var(--accent-green);
}

.delta-card .delta-value.positive::before {
  content: '+';
}

.delta-card .delta-value.negative {
  color: var(--accent-red);
}

.delta-card .delta-value.zero {
  color: var(--text-secondary);
}

/* --------------------------------------------------------------------------
   16. Utility Classes
   -------------------------------------------------------------------------- */
.hidden {
  display: none !important;
}

.text-green {
  color: var(--accent-green);
}

.text-red {
  color: var(--accent-red);
}

.text-amber {
  color: var(--accent-amber);
}

.text-muted {
  color: var(--text-secondary);
}

.text-center {
  text-align: center;
}

.text-right {
  text-align: right;
}

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: 8px; }
.mt-2 { margin-top: 16px; }
.mt-3 { margin-top: 24px; }
.mt-4 { margin-top: 32px; }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: 8px; }
.mb-2 { margin-bottom: 16px; }
.mb-3 { margin-bottom: 24px; }
.mb-4 { margin-bottom: 32px; }

/* --------------------------------------------------------------------------
   17. Loading Spinner
   -------------------------------------------------------------------------- */
.spinner {
  display: inline-block;
  width: 24px;
  height: 24px;
  border: 3px solid var(--border-default);
  border-top-color: var(--accent-green);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

.spinner.spinner-sm {
  width: 16px;
  height: 16px;
  border-width: 2px;
}

.spinner.spinner-lg {
  width: 40px;
  height: 40px;
  border-width: 4px;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Centered spinner block */
.spinner-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 48px 24px;
  color: var(--text-secondary);
  font-size: 0.9375rem;
}

/* --------------------------------------------------------------------------
   18. Fade-In Animation
   -------------------------------------------------------------------------- */
.fade-in {
  animation: fadeIn 0.4s ease-out both;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Staggered fade-in for children */
.fade-in-stagger > * {
  opacity: 0;
  animation: fadeIn 0.4s ease-out both;
}

.fade-in-stagger > *:nth-child(1) { animation-delay: 0.05s; }
.fade-in-stagger > *:nth-child(2) { animation-delay: 0.10s; }
.fade-in-stagger > *:nth-child(3) { animation-delay: 0.15s; }
.fade-in-stagger > *:nth-child(4) { animation-delay: 0.20s; }
.fade-in-stagger > *:nth-child(5) { animation-delay: 0.25s; }
.fade-in-stagger > *:nth-child(6) { animation-delay: 0.30s; }
.fade-in-stagger > *:nth-child(7) { animation-delay: 0.35s; }
.fade-in-stagger > *:nth-child(8) { animation-delay: 0.40s; }

/* --------------------------------------------------------------------------
   19. Scrollbar Styling (Webkit)
   -------------------------------------------------------------------------- */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--border-default);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Firefox */
* {
  scrollbar-width: thin;
  scrollbar-color: var(--border-default) var(--bg-primary);
}

/* --------------------------------------------------------------------------
   20. Section Headings (reusable)
   -------------------------------------------------------------------------- */
.section-title {
  font-size: 1.125rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 16px;
}

.section-subtitle {
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 20px;
}

/* --------------------------------------------------------------------------
   21. Responsive Breakpoints
   -------------------------------------------------------------------------- */

/* Tablets and below — 768px */
@media (max-width: 768px) {
  .container {
    padding: 0 16px;
  }

  header {
    padding: 24px 0 16px;
    margin-bottom: 24px;
  }

  header h1 {
    font-size: 1.375rem;
  }

  /* Tabs scroll horizontally */
  .tab {
    padding: 8px 16px;
    font-size: 0.875rem;
  }

  /* Cost cards: 2 columns */
  .cost-cards {
    grid-template-columns: repeat(2, 1fr);
    gap: 12px;
  }

  .cost-card .cost-value {
    font-size: 1.25rem;
  }

  /* Compare grid stacks */
  .compare-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  /* Stats row wraps */
  .stats-row {
    gap: 16px;
  }

  /* Progress steps scroll */
  .progress-steps {
    gap: 4px;
  }

  .step {
    min-width: 80px;
  }

  .step .step-label {
    font-size: 0.6875rem;
  }

  /* Table horizontal scroll — wrapper handles it */
  .data-table {
    font-size: 0.8125rem;
  }

  .data-table thead th,
  .data-table tbody td {
    padding: 8px 12px;
  }

  /* Delta card */
  .delta-card {
    padding: 16px;
  }

  /* Button full-width on mobile */
  .btn-download {
    width: 100%;
  }
}

/* Small phones — 480px */
@media (max-width: 480px) {
  .container {
    padding: 0 12px;
  }

  header h1 {
    font-size: 1.25rem;
  }

  /* Cost cards: single column */
  .cost-cards {
    grid-template-columns: 1fr;
  }

  /* Stats vertical */
  .stats-row {
    flex-direction: column;
    gap: 12px;
  }

  .stats-row .stat-item {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }

  /* Dropzone smaller */
  .dropzone {
    min-height: 120px;
    padding: 24px 16px;
  }

  .dropzone .dropzone-icon {
    font-size: 2rem;
  }
}

/* Large desktop — wider than max-width */
@media (min-width: 1280px) {
  .container {
    padding: 0 32px;
  }
}

/* --------------------------------------------------------------------------
   22. Print Styles
   -------------------------------------------------------------------------- */
@media print {
  body {
    background: #fff;
    color: #000;
  }

  .tabs,
  .dropzone,
  .btn-primary,
  .btn-secondary,
  .btn-download,
  .progress-steps {
    display: none !important;
  }

  .tab-content {
    display: block !important;
  }

  .cost-card,
  .summary-card,
  .delta-card,
  .accuracy-section {
    box-shadow: none;
    border: 1px solid #ccc;
  }

  .data-table thead th {
    background: #eee;
  }
}