@property --color-accent {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-accent-strong {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-body {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-editor {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-editor-gutter {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-editor-output {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-editor-text {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-focus {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-header {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-header-border {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-header-control {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-header-control-border {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-header-rgb {
  syntax: "*";
  inherits: true;
  initial-value: 0 0 0;
}

@property --color-heading {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-link {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-link-hover {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-link-underline {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-page {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-page-grid-block {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-page-grid-inline {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-panel {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-panel-border {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-panel-divider {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-panel-kicker {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-panel-rule {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-pill-border {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-success {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-success-border {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-success-ink {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-success-muted {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-text {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-toggle-text {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-ui-muted {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-ui-muted-strong {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --color-ui-subtle {
  syntax: "<color>";
  inherits: true;
  initial-value: transparent;
}

@property --font-body {
  syntax: "*";
  inherits: true;
  initial-value: 400 1px / 1 system-ui;
}

@property --font-caption {
  syntax: "*";
  inherits: true;
  initial-value: 600 1px / 1 system-ui;
}

@property --font-caption-strong {
  syntax: "*";
  inherits: true;
  initial-value: 800 1px / 1 system-ui;
}

@property --font-chip {
  syntax: "*";
  inherits: true;
  initial-value: 400 1px / 1 monospace;
}

@property --font-control {
  syntax: "*";
  inherits: true;
  initial-value: 600 1px / 1 system-ui;
}

@property --font-editor {
  syntax: "*";
  inherits: true;
  initial-value: 400 1px / 1 monospace;
}

@property --font-family-body {
  syntax: "*";
  inherits: true;
  initial-value: system-ui;
}

@property --font-family-display {
  syntax: "*";
  inherits: true;
  initial-value: serif;
}

@property --font-family-mono {
  syntax: "*";
  inherits: true;
  initial-value: monospace;
}

@property --font-heading-page {
  syntax: "*";
  inherits: true;
  initial-value: 700 1px / 1 serif;
}

@property --font-heading-panel {
  syntax: "*";
  inherits: true;
  initial-value: 700 1px / 1 serif;
}

@property --font-link {
  syntax: "*";
  inherits: true;
  initial-value: 700 1px / 1 system-ui;
}

@property --font-size-body {
  syntax: "<length>";
  inherits: true;
  initial-value: 15.68px;
}

@property --font-size-caption {
  syntax: "<length>";
  inherits: true;
  initial-value: 11.52px;
}

@property --font-size-chip {
  syntax: "<length>";
  inherits: true;
  initial-value: 12.48px;
}

@property --font-size-control {
  syntax: "<length>";
  inherits: true;
  initial-value: 13.12px;
}

@property --font-size-editor {
  syntax: "<length>";
  inherits: true;
  initial-value: 14.4px;
}

@property --font-size-heading-page {
  syntax: "<length>";
  inherits: true;
  initial-value: 32px;
}

@property --font-size-heading-panel {
  syntax: "<length>";
  inherits: true;
  initial-value: 18.4px;
}

@property --font-size-stat {
  syntax: "<length>";
  inherits: true;
  initial-value: 23.2px;
}

@property --font-size-success {
  syntax: "<length>";
  inherits: true;
  initial-value: 15.2px;
}

@property --font-size-success-detail {
  syntax: "<length>";
  inherits: true;
  initial-value: 14.08px;
}

@property --font-stat {
  syntax: "*";
  inherits: true;
  initial-value: 700 1px / 1 serif;
}

@property --font-success {
  syntax: "*";
  inherits: true;
  initial-value: 700 1px / 1 system-ui;
}

@property --font-success-detail {
  syntax: "*";
  inherits: true;
  initial-value: 400 1px / 1 system-ui;
}

@property --line-height-body {
  syntax: "<number>";
  inherits: true;
  initial-value: 1;
}

@property --line-height-editor {
  syntax: "<number>";
  inherits: true;
  initial-value: 1;
}

@property --line-height-tight {
  syntax: "<number>";
  inherits: true;
  initial-value: 1;
}

@property --line-height-title {
  syntax: "<number>";
  inherits: true;
  initial-value: 1;
}

:root {
  --color-accent: #f3b56d;
  --color-accent-strong: #f0b86b;
  --color-body: #d8d2c2;
  --color-editor: #fffaf0;
  --color-editor-gutter: #eee9dc;
  --color-editor-output: #fdf8ed;
  --color-editor-text: #212821;
  --color-focus: #69b7bc;
  --color-header: #1f251f;
  --color-header-border: rgb(248 243 231 / 0.18);
  --color-header-control: rgb(248 243 231 / 0.08);
  --color-header-control-border: rgb(248 243 231 / 0.25);
  --color-header-rgb: 31 37 31;
  --color-heading: #202820;
  --color-link: #0b5f68;
  --color-link-hover: #073f45;
  --color-link-underline: rgb(11 95 104 / 0.35);
  --color-page: #e7e3d8;
  --color-page-grid-block: rgb(31 37 31 / 0.05);
  --color-page-grid-inline: rgb(31 37 31 / 0.06);
  --color-panel: #f8f3e7;
  --color-panel-border: rgb(31 37 31 / 0.2);
  --color-panel-divider: rgb(31 37 31 / 0.16);
  --color-panel-kicker: #a35622;
  --color-panel-rule: rgb(31 37 31 / 0.12);
  --color-pill-border: rgb(31 37 31 / 0.14);
  --color-success: #dcebc9;
  --color-success-border: rgb(22 57 34 / 0.18);
  --color-success-ink: #163922;
  --color-success-muted: #35543d;
  --color-text: #1f251f;
  --color-toggle-text: #4f594e;
  --color-ui-muted: #697267;
  --color-ui-muted-strong: #384238;
  --color-ui-subtle: #788073;

  --font-body: 400 var(--font-size-body) / var(--line-height-body) var(--font-family-body);
  --font-caption: 600 var(--font-size-caption) / var(--line-height-tight) var(--font-family-body);
  --font-caption-strong: 800 var(--font-size-caption) / var(--line-height-tight)
    var(--font-family-body);
  --font-chip: 400 var(--font-size-chip) / var(--line-height-body) var(--font-family-mono);
  --font-control: 600 var(--font-size-control) / var(--line-height-body) var(--font-family-body);
  --font-editor: 400 var(--font-size-editor) / var(--line-height-editor) var(--font-family-mono);
  --font-family-body: "Avenir Next", "Segoe UI", "Helvetica Neue", sans-serif;
  --font-family-display: "Georgia", "Times New Roman", serif;
  --font-family-mono: "SFMono-Regular", "Consolas", "Liberation Mono", monospace;
  --font-heading-page: 700 var(--font-size-heading-page) / var(--line-height-title)
    var(--font-family-display);
  --font-heading-panel: 700 var(--font-size-heading-panel) / var(--line-height-tight)
    var(--font-family-display);
  --font-link: 700 var(--font-size-body) / var(--line-height-body) var(--font-family-body);
  --font-size-body: 0.98rem;
  --font-size-caption: 0.72rem;
  --font-size-chip: 0.78rem;
  --font-size-control: 0.82rem;
  --font-size-editor: 0.9rem;
  --font-size-heading-page: clamp(2rem, 5vw, 4.5rem);
  --font-size-heading-panel: clamp(1.15rem, 2vw, 1.65rem);
  --font-size-stat: 1.45rem;
  --font-size-success: 0.95rem;
  --font-size-success-detail: 0.88rem;
  --font-stat: 700 var(--font-size-stat) / var(--line-height-tight) var(--font-family-display);
  --font-success: 700 var(--font-size-success) / var(--line-height-body) var(--font-family-body);
  --font-success-detail: 400 var(--font-size-success-detail) / var(--line-height-body)
    var(--font-family-body);
  --line-height-body: 1.5;
  --line-height-editor: 1.55;
  --line-height-tight: 1;
  --line-height-title: 0.92;

  background: var(--color-page);
  color: var(--color-text);
  font: var(--font-body);
  font-synthesis: none;
  /* stylelint-disable-next-line value-keyword-case */
  text-rendering: optimizeLegibility;
}

* {
  box-sizing: border-box;
}

body {
  min-inline-size: 20rem;
  min-block-size: 100svb;
  margin: 0;
  background:
    linear-gradient(90deg, var(--color-page-grid-inline) 0.0625rem, transparent 0.0625rem),
    linear-gradient(0deg, var(--color-page-grid-block) 0.0625rem, transparent 0.0625rem),
    var(--color-page);
  background-size: 1.5rem 1.5rem;
}

css-validator-controller {
  display: block;
  min-block-size: 100svb;
}

button,
input {
  font: inherit;
}

button {
  cursor: pointer;
}

.visually-hidden {
  position: absolute;
  inline-size: 0.0625rem;
  block-size: 0.0625rem;
  border: 0;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

a {
  color: var(--color-link);
  font: var(--font-link);
  text-decoration-color: var(--color-link-underline);
  text-underline-offset: 0.2em;
}

a:hover {
  color: var(--color-link-hover);
}

.app-shell {
  display: grid;
  min-block-size: 0;
  padding-block: clamp(1rem, 2vw, 1.5rem);
  padding-inline: clamp(1rem, 2vw, 1.5rem);
}

.app-header {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 1.5rem;
  margin-block: clamp(1rem, 2vw, 1.5rem) 0;
  margin-inline: clamp(1rem, 2vw, 1.5rem);
  padding-block: clamp(1rem, 2vw, 1.5rem);
  padding-inline: clamp(1rem, 2vw, 1.5rem);
  color: var(--color-panel);
  background: var(--color-header);
  border: 0.0625rem solid var(--color-header-border);
  box-shadow: 0 1.125rem 3.75rem rgb(var(--color-header-rgb) / 0.24);
}

.eyebrow,
.panel-kicker {
  margin-block: 0 0.35rem;
  margin-inline: 0;
  color: var(--color-accent-strong);
  font: var(--font-caption);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.panel-kicker {
  color: var(--color-panel-kicker);
  font: var(--font-caption);
}

h1,
h2 {
  margin: 0;
  letter-spacing: 0;
}

h1 {
  max-inline-size: 16ch;
  font: var(--font-heading-page);
}

h2 {
  color: var(--color-heading);
  font: var(--font-heading-panel);
}

.overview {
  max-inline-size: 68ch;
  margin-block: 0.85rem 0;
  margin-inline: 0;
  color: var(--color-body);
  font: var(--font-body);
}

.app-header a {
  color: var(--color-accent);
}

.header-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0.6rem;
}

.file-button,
.primary-action {
  display: inline-grid;
  min-block-size: 2.6rem;
  place-items: center;
  border: 0.0625rem solid var(--color-header-control-border);
  border-radius: 0.25rem;
  padding-block: 0;
  padding-inline: 1rem;
  font: var(--font-control);
  letter-spacing: 0.01em;
}

.file-button {
  position: relative;
  overflow: hidden;
  color: var(--color-panel);
  background: var(--color-header-control);
}

.file-button input {
  position: absolute;
  inset: 0;
  opacity: 0;
  cursor: pointer;
}

.primary-action {
  color: var(--color-header);
  background: var(--color-accent);
  border-color: var(--color-accent);
}

.file-button:hover,
.primary-action:hover {
  translate: 0 -0.0625rem;
}

.file-button:focus-within,
.primary-action:focus-visible,
.format-toggle input:focus-visible + span {
  outline: 0.1875rem solid var(--color-focus);
  outline-offset: 0.1875rem;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 0.95fr);
  gap: 1rem;
  min-block-size: 0;
}

.panel {
  display: grid;
  grid-template-rows: auto minmax(20rem, 1fr) auto;
  min-inline-size: 0;
  min-block-size: 0;
  background: var(--color-panel);
  border: 0.0625rem solid var(--color-panel-border);
  box-shadow: 0 0.625rem 1.875rem rgb(var(--color-header-rgb) / 0.12);
}

.panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  min-block-size: 5.75rem;
  padding-block: 1rem;
  padding-inline: 1rem;
  border-block-end: 0.0625rem solid var(--color-panel-divider);
}

.input-panel {
  grid-template-rows: auto auto minmax(20rem, 1fr);
}

.validation-status {
  min-block-size: 0;
}

.file-chip {
  overflow: hidden;
  max-inline-size: min(22rem, 45vw);
  padding-block: 0.3rem;
  padding-inline: 0.55rem;
  color: var(--color-ui-muted-strong);
  background: var(--color-page);
  border: 0.0625rem solid var(--color-pill-border);
  border-radius: 62.4375rem;
  font: var(--font-chip);
  text-overflow: ellipsis;
  white-space: nowrap;
}

.format-toggle {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  margin: 0;
  padding-block: 0.25rem;
  padding-inline: 0.25rem;
  background: var(--color-page);
  border: 0.0625rem solid var(--color-header-border);
  border-radius: 0.375rem;
}

.format-toggle legend {
  position: absolute;
  inline-size: 0.0625rem;
  block-size: 0.0625rem;
  border: 0;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
}

.format-toggle label {
  display: block;
  cursor: pointer;
}

.format-toggle input {
  position: absolute;
  opacity: 0;
}

.format-toggle span {
  display: block;
  border-radius: 0.25rem;
  padding-block: 0.35rem;
  padding-inline: 0.65rem;
  color: var(--color-toggle-text);
  cursor: pointer;
  font: var(--font-control);
  letter-spacing: 0.01em;
}

.format-toggle input:checked + span {
  color: var(--color-panel);
  background: var(--color-heading);
}

.editor {
  display: block;
  min-inline-size: 0;
  min-block-size: 0;
}

.code-editor-host,
.cm-editor {
  block-size: 100%;
}

.cm-editor {
  color: var(--color-editor-text);
  background: var(--color-editor);
  font: var(--font-editor);
}

.cm-editor.cm-focused {
  outline: 0.1875rem solid var(--color-focus);
  outline-offset: -0.1875rem;
}

.cm-scroller {
  line-height: var(--line-height-editor);
}

.cm-content,
.cm-gutters {
  min-block-size: 100%;
}

.cm-gutters {
  color: var(--color-ui-subtle);
  background: var(--color-editor-gutter);
  border-inline-end: 0.0625rem solid var(--color-panel-rule);
}

.output-editor .cm-editor {
  background: var(--color-editor-output);
}

.success-message {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin: 0;
  padding-block: 0.85rem;
  padding-inline: 1rem;
  color: var(--color-success-ink);
  background: var(--color-success);
  border-block-end: 0.0625rem solid var(--color-success-border);
}

.success-message strong {
  font: var(--font-success);
}

.success-message span {
  color: var(--color-success-muted);
  font: var(--font-success-detail);
}

.result-stats {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 0;
  border-block-start: 0.0625rem solid var(--color-panel-divider);
}

.result-stats div {
  min-inline-size: 0;
  padding-block: 0.7rem 0.75rem;
  padding-inline: 1rem;
  border-inline-end: 0.0625rem solid var(--color-panel-rule);
}

.result-stats div:last-child {
  border-inline-end: 0;
}

.result-stats dt {
  color: var(--color-ui-muted);
  font: var(--font-caption-strong);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.result-stats dd {
  margin-block: 0.1rem 0;
  margin-inline: 0;
  color: var(--color-heading);
  font: var(--font-stat);
}

@media (width <= 56.25rem) {
  .app-shell {
    min-block-size: auto;
  }

  .app-header,
  .workspace {
    grid-template-columns: 1fr;
  }

  .header-actions {
    justify-content: flex-start;
  }

  .panel {
    min-block-size: 32rem;
  }
}

@media (width <= 38.75rem) {
  .app-shell {
    padding-block: 0.7rem;
    padding-inline: 0.7rem;
  }

  .app-header,
  .panel-header {
    padding-block: 0.85rem;
    padding-inline: 0.85rem;
  }

  .output-header {
    align-items: stretch;
    flex-direction: column;
  }

  .format-toggle {
    inline-size: 100%;
  }

  .format-toggle label {
    flex: 1;
  }

  .format-toggle span {
    text-align: center;
  }

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

  .success-message {
    align-items: flex-start;
    flex-direction: column;
    gap: 0.2rem;
  }
}