/* Shared default theme. Contract: docs/default-theme.md. Disney is independent. */
@layer tokens, base, layout, components, utilities, states;

@layer tokens {
  :root {
    --bg: #0b0b0c;
    --surface: #161618;
    --raised: #222225;
    --line: #303034;
    --text: #f1f1f3;
    --muted: #a2a2ab;
    --accent: #9ec5ff;
    --success: #93d5ad;
    --warning: #e4c182;
    --error: #f2a5a5;
    --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
    --content-max: 60rem;
    --reading-max: 47.5rem;
    --page-gutter: 1.25rem;
    --safe-top: env(safe-area-inset-top, 0px);
    --safe-right: env(safe-area-inset-right, 0px);
    --safe-bottom: env(safe-area-inset-bottom, 0px);
    --safe-left: env(safe-area-inset-left, 0px);
    --gutter-left: max(var(--page-gutter), var(--safe-left));
    --gutter-right: max(var(--page-gutter), var(--safe-right));
    --header-row: 3.5rem;
    --header-padding: .75rem;
    --control-line: #72727c;
    --hover: #343439;
    --radius: .75rem;
  }
}

@layer base {
  :root {
    color-scheme: dark;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    font-size: 100%;
    line-height: 1.6;
    color: var(--text);
    -webkit-text-size-adjust: 100%;
    text-size-adjust: 100%;
  }
  *, *::before, *::after { box-sizing: border-box; }
  html, body { background: var(--bg); }
  body { margin: 0; min-height: 100vh; min-height: 100svh; overflow-wrap: anywhere; }
  /* The measured value handles wrapped navigation and enlarged text. */
  html:has(.header-shell) { scroll-padding-top: calc(var(--header-height, var(--header-row) + var(--header-padding) * 2 + var(--safe-top)) + 1rem); }
  ::selection { background: #35445b; color: #fff; }
  :focus-visible { outline: 2px solid var(--accent); outline-offset: 4px; }
  a { color: var(--accent); text-underline-offset: .2em; text-decoration-thickness: 1px; }
  button, input, select, textarea { font: inherit; }
  h1, h2, h3, h4, h5, h6 { margin: 1.8em 0 .6em; font-family: var(--mono); font-weight: 500; line-height: 1.25; letter-spacing: -.04em; }
  h1 { margin-top: 0; font-size: clamp(2rem, 5vw, 3rem); letter-spacing: -.045em; }
  h2 { font-size: clamp(1.5rem, 3vw, 1.9rem); }
  h3 { font-size: 1.25rem; }
  h4 { font-size: 1.1rem; }
  h5 { font-size: 1rem; }
  h6 { font-size: .9rem; }
  p, ul, ol, dl, pre, blockquote, figure, .table-wrap { margin: 0 0 1.4rem; }
  small, figcaption, caption { font-size: .875rem; color: var(--muted); }
  strong { font-weight: 650; }
  mark { background: #494027; color: #f6e2ad; padding: .1em .2em; }
  hr { margin: 2rem 0; border: 0; border-top: 1px solid var(--line); }
}

@layer layout {
  .page { width: min(calc(100% - var(--gutter-left) - var(--gutter-right)), var(--content-max)); margin-left: max(var(--gutter-left), calc((100% - var(--content-max)) / 2)); margin-right: var(--gutter-right); padding-block: 3rem calc(4rem + var(--safe-bottom)); }
  .reading { --content-max: var(--reading-max); }
  .page > header { margin-bottom: 2.5rem; }
  .section { padding-block: 2.5rem; border-top: 1px solid var(--line); }
  .section > :first-child, .markdown-body > :first-child { margin-top: 0; }
  .section > :last-child, .markdown-body > :last-child { margin-bottom: 0; }
  .columns { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 2rem; }
  .columns > * { min-width: 0; }
  .columns > * > :first-child { margin-top: 0; }
  .stack > * + * { margin-top: 1rem; }
  .actions { display: flex; flex-wrap: wrap; align-items: center; gap: .65rem; }
}

@layer components {
  /* Opaque sticky edge; floating state changes paint only, never dimensions. */
  .header-shell {
    position: static; top: 0; z-index: 20;
    padding: max(var(--header-padding), var(--safe-top)) var(--gutter-right) var(--header-padding) var(--gutter-left);
    background: var(--bg);
  }
  .header-shell.is-ready { position: sticky; }
  .site-header {
    max-width: var(--content-max); margin-inline: auto;
    display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: .25rem .75rem;
    min-height: var(--header-row); padding: .25rem .5rem;
    border: 1px solid transparent; border-radius: 1.5rem;
    transition: border-color 180ms ease, background-color 180ms ease, box-shadow 180ms ease;
  }
  .header-shell.is-floating .site-header {
    border-color: var(--line); background: var(--raised); box-shadow: 0 6px 24px #0004;
  }
  .site-header a { color: var(--text); text-decoration: none; }
  .brand { display: inline-flex; align-items: center; min-height: 2.75rem; font-size: 1.1rem; font-weight: 500; letter-spacing: -.06em; }
  .site-header nav { display: flex; flex-wrap: wrap; gap: .15rem; min-width: 0; }
  .site-header nav a { display: inline-flex; align-items: center; min-height: 2.75rem; padding: .5rem .65rem; border-radius: 1rem; font-size: .875rem; }
  .site-header nav a[aria-current="page"] { background: var(--hover); }
  .article-excerpt { max-width: 65ch; padding-top: 1.5rem; }
  .article-excerpt h3 { margin-top: .5rem; }
  .site-footer { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 1rem; padding-top: 1.5rem; border-top: 1px solid var(--line); color: var(--muted); font-size: .875rem; }
  /* The centered landing layout is deliberately opt-in. */
  .landing { display: grid; place-items: center; padding: var(--safe-top) var(--gutter-right) var(--safe-bottom) var(--gutter-left); }
  .landing main { min-width: 0; padding-block: 2rem; }
  .landing h1 { margin: 0; font: 500 clamp(2.5rem, 8vw, 4rem)/1 "IBM Plex Mono", var(--mono); letter-spacing: -.06em; }
  ul, ol { padding-left: 1.4rem; }
  li + li { margin-top: .35rem; }
  li > ul, li > ol { margin: .4rem 0; }
  dt { color: var(--muted); font-size: .875rem; }
  dd { margin: .15rem 0 1rem; }
  blockquote { border-left: 2px solid #61616a; padding-left: 1.25rem; color: #c2c2ca; }
  blockquote > :last-child { margin-bottom: 0; }
  code, kbd, samp { font-size: .875em; }
  code, kbd { padding: .15em .35em; border-radius: .25rem; background: var(--raised); }
  kbd { border: 1px solid #49494e; }
  pre { padding: 1.25rem; overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); background: var(--surface); line-height: 1.6; }
  pre code { padding: 0; border: 0; background: none; font-size: .8125rem; }
  .table-wrap { overflow-x: auto; border: 1px solid var(--line); border-radius: var(--radius); }
  table { width: 100%; overflow-wrap: normal; border-collapse: collapse; font-size: .875rem; }
  caption { padding: .8rem 1rem; text-align: left; }
  th, td { padding: .9rem 1rem; text-align: left; vertical-align: top; border-bottom: 1px solid var(--line); }
  th { background: var(--surface); font-weight: 600; }
  tbody tr:last-child td { border-bottom: 0; }
  img, video, svg { display: block; max-width: 100%; height: auto; }
  figure img { width: 100%; border-radius: var(--radius); }
  figcaption { margin-top: .65rem; }
  .markdown-body img { margin-block: 1.5rem; border-radius: .5rem; }
  :where(.button, button, input[type="button"], input[type="submit"], input[type="reset"]) {
    display: inline-flex; justify-content: center; align-items: center; gap: .5rem;
    min-height: 2.75rem; padding: .6rem 1rem; border: 1px solid var(--line); border-radius: var(--radius);
    background: var(--raised); color: var(--text); font-weight: 500; line-height: 1.4; text-decoration: none; cursor: pointer;
  }
  .button-primary { background: var(--text); border-color: var(--text); color: var(--bg); }
  .button-quiet { background: transparent; }
  button:disabled, input:disabled, select:disabled, textarea:disabled { opacity: .45; cursor: not-allowed; }
  button:active:not(:disabled), .button:active { transform: translateY(1px); }
  fieldset { min-width: 0; margin: 0 0 1.5rem; padding: 0; border: 0; }
  legend { margin-bottom: 1rem; padding: 0; font-weight: 600; }
  label { display: block; margin-bottom: .4rem; font-size: .875rem; }
  :where(input:not([type="hidden"], [type="checkbox"], [type="radio"], [type="range"], [type="button"], [type="submit"], [type="reset"], [type="image"], [type="color"]), select, textarea) {
    display: block; width: 100%; min-width: 0; min-height: 2.875rem; padding: .7rem .8rem;
    border: 1px solid var(--control-line); border-radius: .65rem; background: var(--surface); color: var(--text);
    /* 16px avoids automatic input zoom on iOS. */
    font-size: max(1rem, 16px);
  }
  /* Constrain the native WebKit date editor, not just its outer input box. */
  input[type="date"] { -webkit-appearance: none; appearance: none; max-width: 100%; min-inline-size: 0; text-align: left; }
  input[type="date"]::-webkit-date-and-time-value { min-width: 0; text-align: left; }
  input[type="date"]::-webkit-datetime-edit { min-width: 0; padding: 0; }
  textarea { resize: vertical; min-height: 7rem; }
  input::placeholder, textarea::placeholder { color: #85858f; opacity: 1; }
  input[readonly] { color: var(--muted); }
  input[type="range"] { min-height: 2.75rem; margin: 0; }
  input[type="color"] { min-width: 2.75rem; min-height: 2.75rem; }
  input[type="range"], progress { width: 100%; accent-color: var(--accent); }
  input[type="checkbox"], input[type="radio"] { width: 1.1rem; height: 1.1rem; margin: 0; accent-color: var(--accent); flex-shrink: 0; }
  .choice { display: flex; align-items: center; gap: .65rem; min-height: 2.75rem; margin: 0; font-size: 1rem; }
  .field { min-width: 0; margin-bottom: 1.25rem; }
  .field small { display: block; margin-top: .4rem; }
  .status { display: inline-block; font: .75rem/1.5 var(--mono); white-space: nowrap; }
  .notice { padding: 1rem 1.2rem; border-left: 2px solid currentColor; background: var(--surface); border-radius: 0 .5rem .5rem 0; }
  .notice p { margin: .25rem 0 0; color: var(--muted); }
  details { border-bottom: 1px solid var(--line); padding-block: 1rem; }
  summary { cursor: pointer; font-weight: 500; min-height: 2.75rem; padding-block: .5rem; }
  details[open] summary { margin-bottom: .75rem; }
  details > :last-child { margin-bottom: 0; }
  [popover] { inset: var(--safe-top) var(--safe-right) var(--safe-bottom) var(--safe-left); max-width: min(28rem, calc(100% - var(--gutter-left) - var(--gutter-right))); max-height: calc(100vh - var(--safe-top) - var(--safe-bottom) - 2rem); max-height: calc(100dvh - var(--safe-top) - var(--safe-bottom) - 2rem); overflow: auto; padding: 1.5rem; border: 1px solid var(--line); border-radius: 1rem; background: var(--raised); color: var(--text); box-shadow: 0 16px 64px #0008; }
  [popover]::backdrop { background: #0008; }
  [popover] > :first-child { margin-top: 0; }
}

@layer utilities {
  .muted, .eyebrow { color: var(--muted); }
  .mono, code, pre, kbd, samp, .eyebrow, .brand { font-family: var(--mono); }
  .eyebrow { margin-bottom: .65rem; font-size: .8125rem; font-weight: 500; letter-spacing: .08em; }
  .eyebrow + :is(h1, h2, h3) { margin-top: 0; }
  .lead { max-width: 58ch; font-size: 1.125rem; color: var(--muted); }
  .align-left { text-align: left; }
  .align-center { text-align: center; }
  .align-right { text-align: right; font-variant-numeric: tabular-nums; }
}

@layer states {
  [hidden]:not([hidden="until-found"]) { display: none; }
  :where(input, select, textarea)[aria-invalid="true"] { border-color: var(--error); }
  :where(.status, .notice).success { color: var(--success); }
  :where(.status, .notice).warning { color: var(--warning); }
  :where(.status, .notice, .field small).error { color: var(--error); }
  @media (hover: hover) and (pointer: fine) {
    a:hover { color: #d2e4ff; }
    .site-header nav a:hover, button:hover:not(:disabled), .button:hover { background: var(--hover); color: var(--text); }
    .button-primary:hover:not(:disabled) { background: #d4d4d9; color: var(--bg); }
  }
  @media (max-width: 40rem) {
    .columns { grid-template-columns: minmax(0, 1fr); gap: 1.5rem; }
    .section { padding-block: 2rem; }
  }
  /* Short viewports must retain reading/focus space, including landscape zoom. */
  @media (max-height: 28rem) {
    .header-shell.is-ready { position: static; }
    html:has(.header-shell) { scroll-padding-top: 1rem; }
  }
  @media (prefers-reduced-motion: reduce) {
    .site-header { transition: none; }
    button:active:not(:disabled), .button:active { transform: none; }
  }
  @media (forced-colors: active) {
    :focus-visible { outline-color: Highlight; }
    .site-header { border-color: CanvasText; box-shadow: none; }
  }
}