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

[hidden] {
  display: none !important;
}

:root {
  --colour-primary: #2563eb;
  --colour-primary-hover: #1d4ed8;
  --colour-primary-light: #dbeafe;
  --colour-accent: #0891b2;
  --colour-bg: #fafafa;
  --colour-bg-secondary: #f4f4f5;
  --colour-bg-tertiary: #e4e4e7;
  --colour-border: #d4d4d8;
  --colour-text: #18181b;
  --colour-text-secondary: #52525b;
  --colour-text-tertiary: #a1a1aa;
  --colour-success: #10b981;
  --colour-success-light: #d1fae5;
  --colour-warning: #f59e0b;
  --colour-warning-light: #fef3c7;
  --colour-info: #3b82f6;
  --colour-info-light: #dbeafe;
  --colour-block-bg: #ffffff;
  --colour-block-border: #e4e4e7;
  --colour-shadow: rgba(0, 0, 0, 0.08);
  --colour-diff-bg: #fef3c7;
  --colour-diff-text: #92400e;

  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 0.75rem;
  --space-lg: 1rem;
  --space-xl: 1.5rem;
  --space-2xl: 2rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --colour-bg: #0a0a0a;
    --colour-bg-secondary: #171717;
    --colour-bg-tertiary: #262626;
    --colour-border: #404040;
    --colour-text: #fafafa;
    --colour-text-secondary: #a1a1aa;
    --colour-text-tertiary: #71717a;
    --colour-block-bg: #171717;
    --colour-block-border: #262626;
    --colour-shadow: rgba(0, 0, 0, 0.5);
    --colour-primary-light: #1e3a8a;
    --colour-info-light: #1e3a8a;
    --colour-diff-bg: #422006;
    --colour-diff-text: #fde68a;
  }
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.5;
  color: var(--colour-text);
  background: var(--colour-bg);
}

a {
  color: var(--colour-primary);
  text-decoration: underline;
}

a:hover {
  color: var(--colour-primary-hover);
}

code {
  font-family: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Monaco, Consolas, monospace;
  font-size: 0.875em;
  padding: var(--space-xs);
  background: var(--colour-bg-secondary);
  border-radius: 0.25rem;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

/* Focus rings */
*:focus-visible {
  outline: 2px solid var(--colour-primary);
  outline-offset: 2px;
}

/* Skip link */
.skip-link {
  position: absolute;
  left: var(--space-sm);
  top: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--colour-primary);
  color: white;
  text-decoration: none;
  border-radius: 0.375rem;
  transform: translateY(-200%);
  transition: transform 0.15s ease;
  z-index: 100;
}

.skip-link:focus {
  transform: translateY(0);
  color: white;
}

/* Screen reader only */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border-width: 0;
}

/* Layout */
.container {
  width: 100%;
  max-width: 1400px;
  margin-inline: auto;
  padding-inline: var(--space-lg);
}

@media (min-width: 768px) {
  .container {
    padding-inline: var(--space-xl);
  }
}

/* Header */
.page-header {
  padding: var(--space-xl) 0;
  background: var(--colour-block-bg);
  border-bottom: 1px solid var(--colour-block-border);
}

.page-header h1 {
  font-family: Georgia, "Times New Roman", Times, serif;
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  margin-bottom: var(--space-sm);
}

@media (min-width: 768px) {
  .page-header h1 {
    font-size: 2.25rem;
  }
}

.lede {
  color: var(--colour-text-secondary);
  max-width: 65ch;
  margin-bottom: var(--space-lg);
}

.alert {
  padding: var(--space-md);
  border-radius: 0.375rem;
  border-left: 4px solid;
  font-size: 0.9375rem;
}

.alert-info {
  background: var(--colour-info-light);
  border-color: var(--colour-info);
  color: var(--colour-text);
}

[data-theme="dark"] .alert-info {
  color: var(--colour-text);
}

/* Controls */
.controls {
  position: sticky;
  top: 0;
  z-index: 10;
  background: var(--colour-bg);
  border-bottom: 1px solid var(--colour-border);
  padding: var(--space-md) 0;
  backdrop-filter: blur(8px);
}

.controls-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-md);
  margin-bottom: var(--space-sm);
  align-items: end;
}

@media (min-width: 768px) {
  .controls-grid {
    grid-template-columns: minmax(0, 2fr) minmax(0, 1fr) auto;
  }
}

.control {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  min-height: 0;
}

.control-toggles {
  flex-direction: row;
  flex-wrap: wrap;
  gap: var(--space-md) var(--space-lg);
  align-items: center;
  /* Align with input baseline: input is 1rem text with ~0.5rem vertical
     padding, so its content centre sits ~0.75rem from the bottom. The
     1rem-tall checkbox needs ~0.25rem below it to land its centre at the
     same vertical position. */
  padding-bottom: 0.4375rem;
}

.form-label {
  font-size: 0.875rem;
  font-weight: 500;
}

.form-hint {
  font-size: 0.8125rem;
  color: var(--colour-text-secondary);
}

.input {
  width: 100%;
  padding: var(--space-sm) var(--space-md);
  font-size: 1rem;
  line-height: 1.5;
  color: var(--colour-text);
  background: var(--colour-bg);
  border: 1px solid var(--colour-border);
  border-radius: 0.375rem;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.input:focus-visible {
  outline: none;
  border-color: var(--colour-primary);
  box-shadow: 0 0 0 3px var(--colour-primary-light);
}

select.input {
  cursor: pointer;
}

.checkbox {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  cursor: pointer;
  font-size: 0.9375rem;
}

.checkbox input[type="checkbox"] {
  width: 1rem;
  height: 1rem;
  cursor: pointer;
  accent-color: var(--colour-primary);
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  font-size: 0.9375rem;
  font-weight: 500;
  background: transparent;
  color: var(--colour-text);
  border: 1px solid var(--colour-border);
  border-radius: 0.375rem;
  transition: all 0.15s ease;
}

.btn:hover {
  background: var(--colour-bg-secondary);
}

.btn-ghost {
  border-color: transparent;
}

.btn-ghost:hover {
  background: var(--colour-bg-secondary);
}

.result-count {
  font-size: 0.875rem;
  color: var(--colour-text-secondary);
}

/* Main */
.main-content {
  padding-top: var(--space-lg);
  padding-bottom: var(--space-2xl);
}

.mobile-hint {
  font-size: 0.875rem;
  color: var(--colour-text-secondary);
  margin-bottom: var(--space-sm);
  padding: var(--space-sm) var(--space-md);
  background: var(--colour-bg-secondary);
  border-radius: 0.375rem;
}

@media (min-width: 900px) {
  .mobile-hint {
    display: none;
  }
}

/* Table wrapper for horizontal scrolling */
.table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  background: var(--colour-block-bg);
  border: 1px solid var(--colour-block-border);
  border-radius: 0.5rem;
  box-shadow: 0 1px 3px var(--colour-shadow);
}

.table-wrap:focus-visible {
  outline: 2px solid var(--colour-primary);
  outline-offset: 2px;
}

.emoji-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  font-size: 0.9375rem;
}

.emoji-table thead th {
  position: sticky;
  top: 0;
  background: var(--colour-bg-secondary);
  text-align: left;
  font-weight: 600;
  padding: var(--space-md);
  border-bottom: 2px solid var(--colour-border);
  white-space: nowrap;
  z-index: 2;
}

.th-sub {
  display: block;
  font-weight: 400;
  font-size: 0.75rem;
  color: var(--colour-text-secondary);
  margin-top: 2px;
}

.emoji-table tbody td,
.emoji-table tbody th {
  padding: var(--space-sm) var(--space-md);
  border-bottom: 1px solid var(--colour-border);
  vertical-align: middle;
  background: var(--colour-block-bg);
}

.emoji-table tbody tr:hover td,
.emoji-table tbody tr:hover th {
  background: var(--colour-bg-secondary);
}

.emoji-table tbody tr:last-child td,
.emoji-table tbody tr:last-child th {
  border-bottom: none;
}

/* Sticky emoji column on mobile */
.col-emoji,
.emoji-table tbody th.cell-emoji {
  position: sticky;
  left: 0;
  z-index: 1;
  background: var(--colour-block-bg);
  border-right: 1px solid var(--colour-border);
}

.emoji-table thead .col-emoji {
  z-index: 3;
  background: var(--colour-bg-secondary);
}

.emoji-table tbody tr:hover th.cell-emoji {
  background: var(--colour-bg-secondary);
}

.cell-emoji {
  font-size: 1.75rem;
  line-height: 1;
  text-align: center;
  font-weight: normal;
  min-width: 3rem;
}

.cell-cp {
  font-family: ui-monospace, "SF Mono", Menlo, Monaco, Consolas, monospace;
  font-size: 0.8125rem;
  color: var(--colour-text-secondary);
  white-space: nowrap;
}

body:not(.show-codepoint) .col-cp,
body:not(.show-codepoint) .cell-cp {
  display: none;
}

.cell-cat,
.col-cat {
  display: none;
}

.col-platform {
  min-width: 14rem;
}

.cell-platform {
  min-width: 14rem;
}

.cell-platform.diff {
  background: var(--colour-diff-bg) !important;
  color: var(--colour-diff-text);
  font-weight: 500;
}

.emoji-table tbody tr:hover .cell-platform.diff {
  background: var(--colour-diff-bg) !important;
}

.note-icon {
  display: inline-block;
  margin-left: var(--space-xs);
  width: 1rem;
  height: 1rem;
  line-height: 1rem;
  text-align: center;
  border-radius: 50%;
  background: var(--colour-text-tertiary);
  color: var(--colour-block-bg);
  font-size: 0.6875rem;
  font-weight: 700;
  cursor: help;
  vertical-align: middle;
}

.loading {
  padding: var(--space-2xl);
  text-align: center;
  color: var(--colour-text-secondary);
}

.empty-row {
  padding: var(--space-2xl);
  text-align: center;
  color: var(--colour-text-secondary);
}

/* Footer */
.page-footer {
  padding: var(--space-xl) 0;
  border-top: 1px solid var(--colour-border);
  font-size: 0.875rem;
  color: var(--colour-text-secondary);
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
  }
}

/* Print: drop sticky behaviour so table flows naturally */
@media print {
  .controls,
  .skip-link,
  .mobile-hint,
  .page-footer {
    display: none;
  }
  .table-wrap {
    overflow: visible;
    border: none;
    box-shadow: none;
  }
  .emoji-table thead th,
  .col-emoji,
  .cell-emoji {
    position: static;
  }
}