/* Reading comfort and keyboard shortcuts.
   Themes only re-point the design tokens defined in ds.css, so every screen that uses a token follows along.
   Text size is the lab's own --lab-scale. Nothing here changes lesson content. */

/* ── themes ─────────────────────────────────────────────────────────────── */
:root[data-comfort-theme="paper"],
html[data-comfort-theme="paper"] body {
  --bg: #f3e9d2;
  --surface: #fbf5e6;
  --surface-2: #f1e6cd;
  --surface-3: #e8dbbd;
  --line: #dccfae;
  --line-strong: #a8946a;
  --ink: #2b2118;
  --ink-2: #3d2f20;
  --ink-3: #54442f;
}
:root[data-comfort-theme="calm"],
html[data-comfort-theme="calm"] body {
  --bg: #e9f0f3;
  --surface: #f6fafb;
  --surface-2: #e3edf1;
  --surface-3: #d6e4ea;
  --line: #cbdbe2;
  --line-strong: #8aa6b3;
  --ink: #10222b;
  --ink-2: #2c4350;
  --ink-3: #455d6a;
}
:root[data-comfort-theme="contrast"],
html[data-comfort-theme="contrast"] body {
  --bg: #ffffff;
  --surface: #ffffff;
  --surface-2: #f2f2f2;
  --surface-3: #e0e0e0;
  --line: #6b6b6b;
  --line-strong: #000000;
  --ink: #000000;
  --ink-2: #111111;
  --ink-3: #222222;
  --right: #0b4d1e;
  --wrong: #8f0000;
  --focus: #000000;
}
:root[data-comfort-theme="contrast"] :focus-visible {
  outline: 3px solid #000;
  outline-offset: 3px;
  box-shadow: 0 0 0 6px #fff;
}
:root[data-comfort-theme="contrast"] a:not(.btn):not(.top-link) {
  text-decoration: underline;
  text-underline-offset: 0.2em;
}
html[data-comfort-theme="paper"] body,
html[data-comfort-theme="calm"] body,
html[data-comfort-theme="contrast"] body {
  background: var(--bg);
  color: var(--ink);
}

/* ── spacing (WCAG 1.4.12 text spacing, applied to reading text only) ──── */
html[data-comfort-lh="roomy"] .lab-main :where(p, li, dd, dt, label, td, th, blockquote, figcaption, textarea) {
  line-height: 1.75;
}
html[data-comfort-lh="airy"] .lab-main :where(p, li, dd, dt, label, td, th, blockquote, figcaption, textarea) {
  line-height: 2.05;
}
html[data-comfort-ls="roomy"] .lab-main :where(p, li, dd, dt, label, td, th, blockquote, figcaption, textarea, h1, h2, h3) {
  letter-spacing: 0.035em;
  word-spacing: 0.1em;
}
html[data-comfort-ls="airy"] .lab-main :where(p, li, dd, dt, label, td, th, blockquote, figcaption, textarea, h1, h2, h3) {
  letter-spacing: 0.07em;
  word-spacing: 0.18em;
}

/* ── calm motion ────────────────────────────────────────────────────────── */
html[data-comfort-motion="calm"] *,
html[data-comfort-motion="calm"] *::before,
html[data-comfort-motion="calm"] *::after {
  animation-duration: 0.01ms !important;
  animation-iteration-count: 1 !important;
  transition-duration: 0.01ms !important;
  scroll-behavior: auto !important;
}

/* ── header button ──────────────────────────────────────────────────────── */
.lab-comfort-btn {
  display: inline-flex;
  gap: 0.4rem;
  align-items: center;
  min-height: 2.75rem;
  border: 0;
  background: transparent;
  font: inherit;
  cursor: pointer;
}
.lab-tools > .top-link.lab-comfort-btn {
  display: inline-flex;
}
/* Icon-only header buttons (search and comfort, below 1500px) keep a full-size touch and click target. */
.lab-search-btn,
.lab-comfort-btn {
  justify-content: center;
  min-width: 2.75rem;
}
/* ds.css hides header icons from 1200 to 1399px; these two buttons are icon-only there, so their icon stays. */
.lab-top .lab-tools > .top-link.lab-search-btn > .ico,
.lab-top .lab-tools > .top-link.lab-comfort-btn > .ico {
  display: inline-block;
}
@media (max-width: 1500px) {
  .lab-comfort-btn span {
    display: none;
  }
}
@media (max-width: 1199px) {
  .lab-tools > .top-link.lab-comfort-btn {
    order: 1;
  }
}

/* ── dialogs: comfort sheet and shortcuts ───────────────────────────────── */
.comfort-dialog,
.shortcuts-dialog {
  max-height: none;
  padding: 0;
  border: 0;
  background: var(--surface);
  color: var(--ink);
  box-shadow: var(--shadow-float);
}
.comfort-dialog::backdrop,
.shortcuts-dialog::backdrop {
  background: rgb(8 14 37 / 48%);
  backdrop-filter: blur(3px);
}
.comfort-dialog {
  width: min(27rem, 100vw);
  height: 100dvh;
  margin: 0 0 0 auto;
  border-radius: var(--r-lg) 0 0 var(--r-lg);
  overflow-y: auto;
}
.shortcuts-dialog {
  width: min(38rem, calc(100vw - 2rem));
  max-height: calc(100dvh - 2rem);
  margin: auto;
  border-radius: var(--r-lg);
  overflow-y: auto;
}
@keyframes comfort-slide {
  from {
    opacity: 0;
    transform: translateX(2rem);
  }
}
@keyframes comfort-pop {
  from {
    opacity: 0;
    transform: translateY(0.75rem) scale(0.98);
  }
}
@media (prefers-reduced-motion: no-preference) {
  html:not([data-comfort-motion="calm"]) .comfort-dialog[open] {
    animation: comfort-slide var(--dur-3, 320ms) var(--ease-out, ease-out);
  }
  html:not([data-comfort-motion="calm"]) .shortcuts-dialog[open] {
    animation: comfort-pop var(--dur-3, 320ms) var(--ease-out, ease-out);
  }
}
.comfort-sheet,
.shortcuts-sheet {
  display: grid;
  gap: var(--s-4);
  padding: var(--s-5);
}
.cm-head {
  display: flex;
  gap: var(--s-3);
  align-items: flex-start;
  justify-content: space-between;
}
.cm-head h2 {
  margin: 0;
  font-family: var(--font-display);
  font-size: 1.6rem;
  line-height: 1.15;
}
.cm-kicker {
  margin: 0 0 0.2rem;
  color: var(--ink-3);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.cm-close {
  display: grid;
  flex: none;
  place-items: center;
  width: var(--target);
  height: var(--target);
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  background: var(--surface-2);
  color: var(--ink);
  cursor: pointer;
}
.cm-close .ico {
  width: 1.1rem;
  height: 1.1rem;
}
.cm-sample {
  margin: 0;
  padding: var(--s-4);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-sm);
  background: var(--surface-2);
  font-size: calc(1.05rem * var(--lab-scale, 1));
}
html[data-comfort-lh="roomy"] .cm-sample { line-height: 1.75; }
html[data-comfort-lh="airy"] .cm-sample { line-height: 2.05; }
html[data-comfort-ls="roomy"] .cm-sample { letter-spacing: 0.035em; word-spacing: 0.1em; }
html[data-comfort-ls="airy"] .cm-sample { letter-spacing: 0.07em; word-spacing: 0.18em; }
.cm-group {
  display: grid;
  gap: var(--s-2);
  margin: 0;
  padding: 0;
  border: 0;
}
.cm-group legend {
  margin-bottom: var(--s-2);
  padding: 0;
  font-weight: 700;
}
.cm-themes {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--s-2);
}
.cm-theme {
  position: relative;
  display: grid;
  gap: 0.15rem;
  padding: var(--s-3);
  border: 2px solid var(--line);
  border-radius: var(--radius);
  background: var(--surface);
  cursor: pointer;
}
.cm-theme small {
  color: var(--ink-3);
  font-size: 0.8rem;
  line-height: 1.3;
}
.cm-theme:has(input:checked) {
  border-color: var(--brand);
  box-shadow: 0 0 0 2px var(--brand);
}
.cm-theme:has(input:focus-visible),
.cm-opt:has(input:focus-visible),
.cm-switch:has(input:focus-visible) {
  outline: 3px solid var(--focus);
  outline-offset: 2px;
}
.cm-theme input,
.cm-opt input {
  position: absolute;
  opacity: 0;
  inset: 0;
  margin: 0;
  cursor: pointer;
}
.cm-swatch {
  display: flex;
  gap: 0.25rem;
  margin-bottom: 0.25rem;
}
.cm-swatch i {
  width: 1.4rem;
  height: 1.4rem;
  border: 1px solid rgb(0 0 0 / 25%);
  border-radius: 50%;
}
[data-theme-card="default"] .cm-swatch i:nth-child(1) { background: #f8f5ef; }
[data-theme-card="default"] .cm-swatch i:nth-child(2) { background: #1d2b58; }
[data-theme-card="default"] .cm-swatch i:nth-child(3) { background: #d28b58; }
[data-theme-card="paper"] .cm-swatch i:nth-child(1) { background: #f3e9d2; }
[data-theme-card="paper"] .cm-swatch i:nth-child(2) { background: #2b2118; }
[data-theme-card="paper"] .cm-swatch i:nth-child(3) { background: #a8946a; }
[data-theme-card="calm"] .cm-swatch i:nth-child(1) { background: #e9f0f3; }
[data-theme-card="calm"] .cm-swatch i:nth-child(2) { background: #10222b; }
[data-theme-card="calm"] .cm-swatch i:nth-child(3) { background: #8aa6b3; }
[data-theme-card="contrast"] .cm-swatch i:nth-child(1) { background: #fff; }
[data-theme-card="contrast"] .cm-swatch i:nth-child(2) { background: #000; }
[data-theme-card="contrast"] .cm-swatch i:nth-child(3) { background: #6b6b6b; }
.cm-row {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: 1fr;
  gap: var(--s-2);
}
.cm-opt {
  position: relative;
  display: grid;
  place-items: center;
  min-height: var(--target);
  padding: 0.4rem 0.5rem;
  border: 2px solid var(--line);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-size: 0.9rem;
  text-align: center;
  cursor: pointer;
}
.cm-opt:has(input:checked) {
  border-color: var(--brand);
  background: var(--brand-soft);
  font-weight: 700;
}
.cm-size span:first-of-type {
  line-height: 1;
}
.cm-switches {
  gap: var(--s-2);
}
.cm-switch {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: var(--s-3);
  align-items: center;
  padding: var(--s-3);
  border: 2px solid var(--line);
  border-radius: var(--radius);
  cursor: pointer;
}
.cm-switch small {
  display: block;
  color: var(--ink-3);
  font-size: 0.82rem;
  line-height: 1.35;
}
.cm-switch input {
  width: 1.4rem;
  height: 1.4rem;
  margin: 0;
  accent-color: var(--brand);
}
.cm-switch:has(input:checked) {
  border-color: var(--brand);
  background: var(--brand-soft);
}
.cm-foot {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-2);
  justify-content: space-between;
}
.cm-note {
  margin: 0;
  color: var(--ink-3);
  font-size: 0.82rem;
}

/* ── reading ruler ──────────────────────────────────────────────────────── */
.comfort-ruler {
  position: fixed;
  inset: 0;
  z-index: 800;
  pointer-events: none;
}
.cr-shade {
  position: absolute;
  right: 0;
  left: 0;
  background: rgb(8 14 37 / 46%);
}
.cr-above {
  top: 0;
  height: var(--cr-top, 40vh);
  border-bottom: 2px solid var(--accent);
}
.cr-below {
  top: var(--cr-bottom, 50vh);
  bottom: 0;
  border-top: 2px solid var(--accent);
}
@media print {
  .comfort-ruler,
  .go-hint {
    display: none !important;
  }
}

/* ── shortcuts ──────────────────────────────────────────────────────────── */
.shortcuts-sheet h3 {
  margin: 0;
  font-size: 0.95rem;
  color: var(--ink-3);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.sc-list {
  display: grid;
  gap: 0.35rem;
  margin: 0;
}
.sc-go {
  grid-template-columns: 1fr 1fr;
  column-gap: var(--s-5);
}
.sc-row {
  display: flex;
  gap: var(--s-3);
  align-items: center;
}
.sc-row dt {
  display: flex;
  flex: none;
  gap: 0.3rem;
  align-items: center;
  min-width: 4.4rem;
  color: var(--ink-3);
  font-size: 0.75rem;
}
.sc-row dd {
  margin: 0;
}
kbd {
  display: inline-block;
  min-width: 1.6rem;
  padding: 0.1rem 0.45rem;
  border: 1px solid var(--line-strong);
  border-bottom-width: 3px;
  border-radius: 6px;
  background: var(--surface-2);
  color: var(--ink);
  font: 700 0.85rem/1.4 var(--font);
  text-align: center;
}
.go-hint {
  position: fixed;
  right: 50%;
  bottom: var(--s-4);
  z-index: 900;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 0.9rem;
  align-items: center;
  justify-content: center;
  width: min(44rem, calc(100vw - 1.5rem));
  padding: var(--s-3) var(--s-4);
  border-radius: var(--r-lg);
  background: var(--brand-deep);
  color: #fff;
  font-size: 0.9rem;
  transform: translateX(50%);
  box-shadow: var(--shadow-float);
}
.go-hint kbd {
  background: #fff;
  color: var(--brand-deep);
  border-color: #fff;
}
@media (max-width: 560px) {
  .sc-go {
    grid-template-columns: 1fr;
  }
  .cm-themes {
    grid-template-columns: 1fr;
  }
}