:root {
  color-scheme: light dark;
  --bg: oklch(1 0 0);
  --surface: oklch(0.974 0 0);
  --surface-strong: oklch(0.94 0 0);
  --ink: oklch(0.17 0.006 15);
  --muted: oklch(0.43 0.008 15);
  --line: oklch(0.86 0.004 15);
  --line-strong: oklch(0.7 0.008 15);
  --primary: oklch(0.45 0.15 0);
  --primary-hover: oklch(0.39 0.145 0);
  --primary-soft: oklch(0.96 0.025 0);
  --focus: oklch(0.55 0.17 0);
  --inverse: oklch(0.985 0 0);
  --radius-control: 0.625rem;
  --radius-panel: 0.875rem;
  --content: 76rem;
  --font: "Segoe UI Variable", "Segoe UI", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: "Cascadia Code", "SFMono-Regular", Consolas, monospace;
  font-family: var(--font);
  font-synthesis: none;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: oklch(0.115 0 0);
    --surface: oklch(0.16 0.004 15);
    --surface-strong: oklch(0.215 0.006 15);
    --ink: oklch(0.94 0.004 15);
    --muted: oklch(0.72 0.008 15);
    --line: oklch(0.3 0.008 15);
    --line-strong: oklch(0.48 0.01 15);
    --primary: oklch(0.64 0.16 0);
    --primary-hover: oklch(0.7 0.15 0);
    --primary-soft: oklch(0.22 0.035 0);
    --focus: oklch(0.72 0.15 0);
    --inverse: oklch(0.12 0 0);
  }
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-size: 1rem;
  line-height: 1.5;
  text-rendering: optimizeLegibility;
}

button,
input {
  font: inherit;
}

button {
  color: inherit;
}

button:not(:disabled),
label[for] {
  cursor: pointer;
}

button:focus-visible,
input:focus-visible,
summary:focus-visible,
a:focus-visible,
[tabindex="-1"]:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2,
h3 {
  text-wrap: balance;
}

p {
  text-wrap: pretty;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: -9999px;
  z-index: 50;
  padding: 0.65rem 0.9rem;
  border-radius: var(--radius-control);
  background: var(--ink);
  color: var(--bg);
  transition: left 160ms ease-out;
}

.skip-link:focus {
  left: 0.75rem;
}

.site-header {
  min-height: 4.25rem;
  max-width: var(--content);
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  color: var(--ink);
  font-weight: 720;
  letter-spacing: -0.02em;
  text-decoration: none;
  white-space: nowrap;
}

.brand-mark {
  width: 1.85rem;
  height: 1.85rem;
  position: relative;
  display: inline-block;
  border-radius: 0.4rem;
  background: var(--primary);
}

.brand-mark span {
  position: absolute;
  left: 0.45rem;
  width: 0.95rem;
  height: 0.18rem;
  border-radius: 999px;
  background: var(--inverse);
  transform: rotate(-32deg);
}

.brand-mark span:first-child { top: 0.65rem; }
.brand-mark span:last-child { top: 1.05rem; }

.header-actions,
.language-switch {
  display: flex;
  align-items: center;
}

.header-actions {
  gap: 1rem;
}

.local-status {
  color: var(--muted);
  font-size: 0.875rem;
}

.language-switch {
  padding: 0.2rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-control);
  background: var(--surface);
}

.language-switch button {
  min-width: 2.9rem;
  padding: 0.38rem 0.55rem;
  border: 0;
  border-radius: 0.4rem;
  background: transparent;
  font-size: 0.8125rem;
  font-weight: 700;
}

.language-switch button[aria-pressed="true"] {
  background: var(--ink);
  color: var(--bg);
}

main,
footer {
  max-width: var(--content);
  margin: 0 auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.hero {
  min-height: min(29rem, calc(100dvh - 4.25rem));
  display: grid;
  grid-template-columns: minmax(0, 1.45fr) minmax(18rem, 0.55fr);
  gap: clamp(2rem, 8vw, 7rem);
  align-items: center;
  padding-top: 3.5rem;
  padding-bottom: 3.5rem;
}

.hero-copy {
  max-width: 47rem;
}

.eyebrow,
.result-context {
  color: var(--primary);
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 700;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}

h1 {
  max-width: 20ch;
  margin-bottom: 1.5rem;
  font-size: clamp(2.75rem, 4vw, 3.6rem);
  line-height: 1.02;
  letter-spacing: -0.04em;
  font-weight: 760;
}

.hero-subtitle {
  max-width: 58ch;
  margin-bottom: 0;
  color: var(--muted);
  font-size: clamp(1.05rem, 1.4vw, 1.25rem);
}

.scope-note {
  align-self: end;
  margin-bottom: 1.25rem;
  padding-top: 1.25rem;
  border-top: 2px solid var(--ink);
}

.scope-note h2 {
  margin-bottom: 1.25rem;
  font-size: 1rem;
}

.scope-note dl {
  margin: 0;
}

.scope-note dl div {
  display: grid;
  grid-template-columns: minmax(6rem, 0.8fr) minmax(0, 1.2fr);
  gap: 1rem;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--line);
}

.scope-note dt {
  font-weight: 700;
}

.scope-note dd {
  margin: 0;
  color: var(--muted);
  font-size: 0.875rem;
}

.workspace,
.results {
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-panel);
  background: var(--surface);
}

.workspace {
  padding: clamp(1.25rem, 3vw, 2.25rem);
}

.workspace-heading,
.results-heading,
.export-panel,
.compare-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 1.5rem;
}

.workspace-heading h2,
.results-heading h2,
.method h2 {
  margin-bottom: 0.4rem;
  font-size: clamp(1.5rem, 2vw, 2rem);
  letter-spacing: -0.025em;
}

.workspace-heading p,
.compare-bar p,
.export-panel p,
.method p {
  margin-bottom: 0;
  color: var(--muted);
}

.text-button {
  padding: 0.25rem;
  border: 0;
  background: transparent;
  color: var(--primary);
  font-weight: 720;
  text-decoration: underline;
  text-underline-offset: 0.2em;
}

.file-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 2rem 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius-panel);
  background: var(--line);
}

.file-slot {
  min-width: 0;
  padding: clamp(1rem, 2.5vw, 1.75rem);
  background: var(--bg);
}

.slot-heading {
  display: flex;
  gap: 0.875rem;
  align-items: flex-start;
  min-height: 4.5rem;
}

.slot-letter {
  flex: 0 0 auto;
  width: 1.8rem;
  height: 1.8rem;
  display: grid;
  place-items: center;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  font-family: var(--mono);
  font-size: 0.75rem;
  font-weight: 800;
}

.slot-heading h3 {
  margin-bottom: 0.15rem;
  font-size: 1rem;
}

.slot-heading p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.875rem;
}

.drop-zone {
  min-height: 9.5rem;
  padding: 1.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  border: 1px dashed var(--line-strong);
  border-radius: var(--radius-control);
  background: var(--surface);
  text-align: center;
  transition: border-color 160ms ease-out, background 160ms ease-out, transform 160ms ease-out;
}

.drop-zone:hover,
.drop-zone.is-dragging {
  border-color: var(--primary);
  background: var(--primary-soft);
}

.drop-zone:active {
  transform: translateY(1px);
}

.drop-zone input {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  opacity: 0;
}

.drop-zone:has(input:focus-visible) {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}

.drop-main {
  font-weight: 720;
}

.drop-help,
.file-meta {
  color: var(--muted);
  font-size: 0.8125rem;
}

.file-meta {
  min-height: 2.6rem;
  margin-top: 0.85rem;
  padding: 0.6rem 0.75rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  border-radius: var(--radius-control);
  background: var(--surface);
}

.file-meta[data-empty="false"] {
  color: var(--ink);
}

.file-meta strong {
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.file-meta small {
  flex: 0 0 auto;
  color: var(--muted);
}

.compare-bar {
  padding-top: 1.25rem;
  border-top: 1px solid var(--line);
}

.primary-button,
.secondary-button {
  min-height: 2.75rem;
  padding: 0.7rem 1rem;
  border-radius: var(--radius-control);
  font-weight: 730;
  line-height: 1;
  white-space: nowrap;
  transition: background 160ms ease-out, border-color 160ms ease-out, transform 160ms ease-out;
}

.primary-button {
  border: 1px solid var(--primary);
  background: var(--primary);
  color: oklch(0.99 0 0);
}

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

.primary-button:active:not(:disabled),
.secondary-button:active,
.filter-button:active,
.summary button:active {
  transform: translateY(1px);
}

.primary-button:disabled {
  border-color: var(--line-strong);
  background: var(--surface-strong);
  color: var(--muted);
  cursor: not-allowed;
}

.secondary-button {
  border: 1px solid var(--line-strong);
  background: var(--bg);
}

.secondary-button:hover {
  border-color: var(--ink);
}

.workspace-error {
  margin-top: 1rem;
  padding: 0.85rem 1rem;
  border: 1px solid var(--primary);
  border-radius: var(--radius-control);
  background: var(--primary-soft);
  color: var(--ink);
  font-weight: 650;
}

.results {
  margin-top: 1.5rem;
  padding: clamp(1.25rem, 3vw, 2.25rem);
}

.result-context {
  margin-bottom: 0.25rem;
}

.recommendation {
  margin: 1.75rem 0;
  padding: 1.25rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-control);
  background: var(--bg);
}

.recommendation[data-state="hold"] {
  border-color: var(--primary);
  background: var(--primary-soft);
}

.recommendation h3 {
  margin-bottom: 0.3rem;
  font-size: 1.1rem;
}

.recommendation p {
  max-width: 70ch;
  margin-bottom: 0;
  color: var(--muted);
}

.recommendation-action {
  flex: 0 0 auto;
}

.summary {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.summary button {
  padding: 1.25rem;
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  border: 0;
  border-right: 1px solid var(--line);
  background: transparent;
  text-align: left;
}

.summary button:last-child {
  border-right: 0;
}

.summary button:hover {
  background: var(--bg);
}

.summary button.is-active {
  background: var(--ink);
  color: var(--bg);
}

.summary button.is-active span {
  color: color-mix(in oklch, var(--bg) 72%, var(--ink));
}

.summary strong {
  font-family: var(--mono);
  font-size: 1.8rem;
  line-height: 1.1;
}

.summary span {
  color: var(--muted);
  font-size: 0.8125rem;
}

.result-tools {
  margin: 1.5rem 0 1rem;
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 1.5rem;
}

.filter-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

.filter-button {
  padding: 0.48rem 0.72rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-control);
  background: var(--bg);
  font-size: 0.8125rem;
  font-weight: 680;
}

.filter-button:hover,
.filter-button.is-active {
  border-color: var(--ink);
}

.filter-button.is-active {
  background: var(--ink);
  color: var(--bg);
}

.search-field {
  width: min(100%, 19rem);
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 680;
}

.search-field input {
  width: 100%;
  min-height: 2.5rem;
  padding: 0.55rem 0.7rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-control);
  background: var(--bg);
  color: var(--ink);
}

.search-field input::placeholder {
  color: var(--muted);
  opacity: 1;
}

.result-list {
  border-top: 1px solid var(--line-strong);
}

.result-count {
  margin: 0 0 0.55rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.75rem;
}

.result-item {
  border-bottom: 1px solid var(--line);
}

.result-item summary {
  position: relative;
  padding: 1rem 2.25rem 1rem 0;
  display: grid;
  grid-template-columns: minmax(7rem, 0.7fr) minmax(0, 1.3fr) minmax(6rem, 0.55fr);
  gap: 1rem;
  align-items: center;
  list-style: none;
  cursor: pointer;
}

.result-item summary::-webkit-details-marker { display: none; }

.result-item summary::after {
  content: "+";
  position: absolute;
  right: 0.25rem;
  font-family: var(--mono);
  font-size: 1.1rem;
}

.result-item[open] summary::after { content: "−"; }

.type-label {
  width: fit-content;
  padding: 0.25rem 0.45rem;
  border: 1px solid var(--line-strong);
  border-radius: 0.4rem;
  font-size: 0.72rem;
  font-weight: 800;
}

.type-label[data-type="error"],
.type-label[data-type="risk"] {
  border-color: var(--primary);
  color: var(--primary);
}

.result-main {
  min-width: 0;
}

.result-main strong {
  display: block;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.result-main span,
.result-confidence {
  color: var(--muted);
  font-size: 0.8125rem;
}

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

.result-detail {
  padding: 0 0 1.2rem calc(7rem + 1rem);
}

.result-detail p {
  max-width: 70ch;
  margin-bottom: 1rem;
}

.detail-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.25rem;
  color: var(--muted);
  font-size: 0.8125rem;
}

.before-after {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.75rem;
}

.before-after div {
  min-width: 0;
  padding: 0.75rem;
  border-radius: var(--radius-control);
  background: var(--surface-strong);
}

.before-after span {
  display: block;
  margin-bottom: 0.25rem;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 700;
}

.before-after code {
  overflow-wrap: anywhere;
  font-family: var(--mono);
  font-size: 0.78rem;
}

.result-empty,
.no-differences {
  padding: 3rem 1rem;
  text-align: center;
}

.result-empty h3,
.no-differences h3 {
  margin-bottom: 0.4rem;
}

.result-empty p,
.no-differences p {
  max-width: 60ch;
  margin: 0 auto;
  color: var(--muted);
}

.export-panel {
  margin-top: 2rem;
  padding: 1.5rem;
  border-radius: var(--radius-panel);
  background: var(--ink);
  color: var(--bg);
}

.export-panel h3 {
  margin-bottom: 0.3rem;
}

.export-panel p {
  max-width: 58ch;
  color: color-mix(in oklch, var(--bg) 72%, var(--ink));
}

.export-actions {
  display: flex;
  gap: 0.65rem;
}

.export-panel .secondary-button {
  border-color: color-mix(in oklch, var(--bg) 52%, var(--ink));
  background: transparent;
  color: var(--bg);
}

.method {
  display: grid;
  grid-template-columns: minmax(0, 0.8fr) minmax(20rem, 1.2fr);
  gap: clamp(2rem, 8vw, 7rem);
  padding-top: 5.5rem;
  padding-bottom: 5.5rem;
}

.method details {
  align-self: start;
  border-top: 2px solid var(--ink);
  border-bottom: 1px solid var(--line);
}

.method summary {
  padding: 1rem 2rem 1rem 0;
  position: relative;
  font-weight: 740;
  cursor: pointer;
}

.method summary::marker { color: var(--primary); }

.details-copy {
  padding: 0 0 1rem;
}

.details-copy p {
  margin-bottom: 0.75rem;
}

footer {
  min-height: 6.5rem;
  padding-top: 1.5rem;
  padding-bottom: 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.8125rem;
}

footer p { margin-bottom: 0; }

.loading-state {
  display: grid;
  gap: 0.75rem;
  padding: 1rem 0;
}

.loading-state div {
  height: 4rem;
  border-radius: var(--radius-control);
  background: var(--surface-strong);
}

@media (prefers-reduced-motion: no-preference) {
  .loading-state div {
    background: linear-gradient(90deg, var(--surface-strong), var(--bg), var(--surface-strong));
    background-size: 220% 100%;
    animation: shimmer 1.25s ease-in-out infinite;
  }

  @keyframes shimmer {
    to { background-position: -220% 0; }
  }
}

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

[hidden] { display: none !important; }

@media (max-width: 767px) {
  html { scroll-behavior: auto; }

  .site-header {
    min-height: 4rem;
    padding: 0 1rem;
  }

  .brand { font-size: 0.9rem; }
  .brand-mark { width: 1.65rem; height: 1.65rem; }
  .brand-mark span { left: 0.4rem; width: 0.85rem; }
  .brand-mark span:first-child { top: 0.58rem; }
  .brand-mark span:last-child { top: 0.94rem; }
  .local-status { display: none; }
  .header-actions { gap: 0.5rem; }

  main,
  footer {
    padding-left: 1rem;
    padding-right: 1rem;
  }

  .hero {
    min-height: auto;
    grid-template-columns: 1fr;
    gap: 2.5rem;
    padding-top: 3.5rem;
    padding-bottom: 3rem;
  }

  h1 {
    max-width: 12ch;
    font-size: clamp(2.35rem, 11vw, 3.5rem);
  }

  .scope-note { margin-bottom: 0; }

  .workspace,
  .results { padding: 1rem; }

  .workspace-heading,
  .results-heading,
  .recommendation,
  .export-panel,
  .compare-bar,
  .result-tools,
  footer {
    align-items: stretch;
    flex-direction: column;
  }

  .workspace-heading .text-button { align-self: flex-start; }

  .file-grid {
    grid-template-columns: 1fr;
    margin: 1.5rem 0;
  }

  .compare-bar .primary-button,
  .export-actions .primary-button,
  .export-actions .secondary-button {
    width: 100%;
  }

  .summary {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .summary button:nth-child(2) { border-right: 0; }
  .summary button:nth-child(-n+2) { border-bottom: 1px solid var(--line); }

  .search-field { width: 100%; }

  .result-item summary {
    grid-template-columns: minmax(6.8rem, auto) minmax(0, 1fr);
    gap: 0.7rem;
  }

  .result-confidence {
    grid-column: 2;
    text-align: left;
  }

  .result-detail { padding-left: 0; }
  .before-after { grid-template-columns: 1fr; }

  .export-actions {
    display: grid;
    grid-template-columns: 1fr;
  }

  .method {
    grid-template-columns: 1fr;
    gap: 2rem;
    padding-top: 4rem;
    padding-bottom: 4rem;
  }

  footer { justify-content: center; }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}