:root {
  color-scheme: light;
  --ink: #182e42;
  --muted: #63717d;
  --accent: #5428a6;
  --tint: #f2edf9;
  --line: #dde3e8;
  --paper: #f7f8fa;
  --success: #23694d;
  font-family: "Aptos", "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  font-synthesis: none;
}
* {
  box-sizing: border-box;
}
body {
  margin: 0;
}
button,
input,
select {
  font: inherit;
}
button,
a,
select {
  -webkit-tap-highlight-color: transparent;
}
button,
a {
  touch-action: manipulation;
}
a {
  color: inherit;
  text-underline-offset: 0.22em;
}
button {
  cursor: pointer;
}
button:disabled {
  cursor: default;
  opacity: 0.5;
}
button,
.button {
  border: 0;
  border-radius: 0.55rem;
  padding: 0.75rem 1.1rem;
  background: var(--accent);
  color: white;
  font-weight: 650;
  text-decoration: none;
}
button:hover,
.button:hover {
  filter: brightness(0.94);
}
button.secondary,
.button.secondary {
  background: white;
  color: var(--ink);
  border: 1px solid var(--line);
}
button.quiet {
  padding: 0.6rem;
  color: var(--muted);
  background: transparent;
}
:focus-visible {
  outline: 3px solid #7b54c3;
  outline-offset: 4px;
}
[tabindex="-1"]:focus {
  outline: none;
}
.sr-only,
.skip:not(:focus) {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}
.skip:focus {
  display: block;
  padding: 1rem;
}
.header {
  height: 84px;
  padding: 0 clamp(1rem, 4vw, 4rem);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  background: white;
  gap: 1rem;
}
.brand {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  text-decoration: none;
}
.brand img {
  width: 134px;
  height: 32px;
}
.brand span {
  padding-left: 1.25rem;
  border-left: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.9rem;
}
.header-actions {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}
.header select {
  border: none;
  background: transparent;
  color: var(--ink);
  padding: 0.7rem 0.25rem;
}
.work-link {
  font-size: 0.9rem;
  font-weight: 650;
}
.loading {
  margin: 4rem;
}
.overview {
  max-width: 1280px;
  margin: auto;
  padding: 3.5rem 2rem 5rem;
}
.eyebrow {
  color: var(--accent);
  font-size: 0.76rem;
  font-weight: 750;
  letter-spacing: 0.13em;
  text-transform: uppercase;
  margin: 0 0 1rem;
}
.hero {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 4rem;
  align-items: end;
  margin-bottom: 3rem;
}
h1 {
  font-size: clamp(2rem, 4.5vw, 3.7rem);
  line-height: 1.1;
  letter-spacing: -0.045em;
  margin: 0 0 1.25rem;
  font-weight: 720;
}
.intro {
  color: var(--muted);
  font-size: 1.1rem;
  line-height: 1.7;
  max-width: 38rem;
  margin: 0;
}
.start {
  border-left: 3px solid var(--accent);
  padding: 0.4rem 0 0.4rem 1.5rem;
}
.start h2 {
  font-size: 1.2rem;
  margin: 0 0 0.6rem;
}
.start p {
  color: var(--muted);
  line-height: 1.5;
  margin: 0 0 1.25rem;
}
.start .button {
  display: inline-flex;
}
.search-row {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin: 2rem 0;
}
.search-row input {
  width: min(100%, 39rem);
  padding: 1rem 1.2rem;
  border: 1px solid #c8d1d9;
  border-radius: 0.65rem;
  background: white;
}
.count {
  color: var(--muted);
  font-size: 0.9rem;
}
.group {
  margin-top: 2.25rem;
}
.group-heading {
  display: flex;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.9rem;
  align-items: baseline;
}
.group-heading h2 {
  font-size: 1.1rem;
  margin: 0;
}
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.8rem 1.5rem;
  margin-top: 0.5rem;
}
.card {
  display: flex;
  gap: 1rem;
  align-items: center;
  text-decoration: none;
  padding: 1.15rem 0;
  border-bottom: 1px solid var(--line);
}
.card:hover strong {
  color: var(--accent);
}
.card-icon {
  border-radius: 0.5rem;
  width: 2.6rem;
  height: 2.6rem;
  display: grid;
  place-items: center;
  background: white;
  border: 1px solid var(--line);
  color: var(--accent);
  flex-shrink: 0;
}
.card strong {
  display: block;
  font-size: 0.98rem;
}
.card small {
  display: block;
  margin-top: 0.4rem;
  color: var(--muted);
}
.card-arrow {
  margin-left: auto;
  color: var(--muted);
}
.footnote {
  margin-top: 2.5rem;
  font-size: 0.85rem;
  color: var(--muted);
  line-height: 1.6;
}
.guide {
  display: grid;
  grid-template-columns: 272px minmax(0, 1fr);
  min-height: calc(100dvh - 84px);
}
.chapters {
  border-right: 1px solid var(--line);
  background: white;
  padding: 1.75rem 1rem;
}
.all-guides {
  display: inline-block;
  font-size: 0.9rem;
  margin: 0 0.75rem 2rem;
  color: var(--muted);
  text-decoration: none;
}
.chapters h2 {
  margin: 0 0.75rem 1rem;
  font-size: 1.2rem;
}
.chapter-menu summary {
  display: none;
}
.chapter-list {
  margin: 1.5rem 0;
  padding: 0;
  list-style: none;
}
.chapter {
  display: flex;
  align-items: start;
  gap: 0.8rem;
  padding: 0.85rem 0.75rem;
  text-decoration: none;
  border-radius: 0.5rem;
  margin-bottom: 0.25rem;
  font-size: 0.9rem;
  line-height: 1.45;
}
.chapter:hover {
  background: var(--paper);
}
.chapter[aria-current] {
  background: var(--tint);
  color: var(--accent);
  font-weight: 650;
}
.chapter-number {
  flex-shrink: 0;
  width: 1.4rem;
  font-variant-numeric: tabular-nums;
  opacity: 0.7;
}
.chapter.is-done .chapter-number {
  color: var(--success);
  opacity: 1;
}
.progress-label {
  font-size: 0.8rem;
  color: var(--muted);
  margin: 0.5rem 0.75rem;
}
progress {
  width: calc(100% - 1.5rem);
  margin: 0 0.75rem;
  height: 5px;
  accent-color: var(--accent);
}
.lesson {
  width: 100%;
  max-width: 1300px;
  margin: 0 auto;
  padding: 2rem clamp(1.25rem, 3vw, 3rem) 3rem;
}
.lesson-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 1.75rem;
}
.lesson-top .eyebrow {
  margin: 0;
}
.lesson h1 {
  font-size: clamp(1.7rem, 3vw, 2.65rem);
  max-width: 48rem;
  margin-bottom: 1rem;
}
.instruction {
  font-size: 1.05rem;
  line-height: 1.7;
  max-width: 58rem;
  margin: 0 0 1.5rem;
}
.image-card {
  background: white;
  border: 1px solid var(--line);
  border-radius: 0.8rem;
  padding: 1rem;
  margin: 0 0 1.25rem;
}
.image-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.8rem;
  font-size: 0.82rem;
  color: var(--muted);
}
.image-toolbar button {
  padding: 0.4rem 0.6rem;
  font-size: 0.82rem;
}
.screenshot {
  position: relative;
  width: 100%;
}
.screenshot img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 0.2rem;
}
.marker-links {
  display: none;
}
.hotspot {
  position: absolute;
  transform: translate(-50%, -50%);
  background: var(--accent);
  border: 3px solid white;
  box-shadow:
    0 0 0 2px var(--accent),
    0 2px 10px #2223;
  width: 32px;
  height: 32px;
  padding: 0;
  border-radius: 50%;
  display: grid;
  place-items: center;
  font-size: 0.8rem;
}
.hotspot[aria-pressed="true"] {
  background: var(--success);
  box-shadow: 0 0 0 2px var(--success);
}
.hint {
  margin: 0.9rem 0 0;
  font-size: 0.87rem;
  line-height: 1.5;
  color: var(--muted);
}
.result {
  background: #edf5f0;
  border-left: 3px solid var(--success);
  border-radius: 0 0.5rem 0.5rem 0;
  padding: 0.9rem 1rem;
  color: #23503d;
  margin: 1rem 0;
  line-height: 1.6;
}
.result strong {
  display: block;
  font-size: 0.8rem;
  margin-bottom: 0.3rem;
}
.result:empty {
  display: none;
}
.note {
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.65;
}
.lesson-footer {
  display: flex;
  gap: 0.75rem;
  align-items: center;
  justify-content: space-between;
  border-top: 1px solid var(--line);
  padding-top: 1.3rem;
  margin-top: 1.7rem;
}
.lesson-footer > div {
  display: flex;
  gap: 0.6rem;
  align-items: center;
}
.practice {
  margin: 1.2rem 0;
  border: 1px solid #d4c7ed;
  background: #faf8fe;
  border-radius: 0.8rem;
  padding: 1.25rem;
}
.practice h2 {
  font-size: 1.05rem;
  margin: 0 0 0.6rem;
}
.practice p {
  font-size: 0.9rem;
  line-height: 1.5;
}
.practice label {
  display: inline-flex;
  gap: 0.6rem;
  align-items: center;
  margin: 0.75rem 0.75rem 0.75rem 0;
  font-size: 0.9rem;
}
.practice select {
  padding: 0.5rem;
  border: 1px solid #c5bbd8;
  border-radius: 0.3rem;
  background: white;
}
.practice input[type="checkbox"] {
  width: 1.1rem;
  height: 1.1rem;
  accent-color: var(--accent);
}
.practice table {
  width: 100%;
  border-collapse: collapse;
  background: white;
  font-size: 0.9rem;
}
.practice th,
.practice td {
  text-align: left;
  padding: 0.7rem;
  border-bottom: 1px solid var(--line);
}
.practice th {
  font-weight: 650;
  color: var(--muted);
}
.practice-output {
  color: var(--success);
  min-height: 1.4rem;
}
.answers {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
}
.completion {
  padding: 1.5rem;
  background: #edf5f0;
  border: 1px solid #cadfd1;
  border-radius: 0.8rem;
  margin-top: 1.5rem;
}
.completion h2 {
  margin: 0 0 0.75rem;
  font-size: 1.2rem;
}
.completion p {
  line-height: 1.6;
}
dialog {
  max-width: 96vw;
  width: max-content;
  max-height: 94dvh;
  border: 0;
  border-radius: 0.7rem;
  padding: 1rem;
  box-shadow: 0 12px 70px #0005;
}
dialog::backdrop {
  background: #14283dcc;
}
dialog form {
  position: sticky;
  top: 0;
  text-align: right;
  margin-bottom: 0.75rem;
}
dialog img {
  display: block;
  max-width: none;
  width: auto;
}
@media (max-width: 850px) {
  .cards {
    grid-template-columns: repeat(2, 1fr);
  }
  .hero {
    gap: 2rem;
  }
  .guide {
    grid-template-columns: 220px minmax(0, 1fr);
  }
  .lesson-footer,
  .lesson-footer > div {
    flex-wrap: wrap;
  }
}
@media (max-width: 620px) {
  .header {
    height: 72px;
    padding: 0 1rem;
    gap: 0.5rem;
  }
  .brand img {
    width: 105px;
  }
  .brand span {
    display: none;
  }
  .header-actions {
    gap: 0.65rem;
  }
  .header-actions select,
  .work-link {
    font-size: 0.8rem;
  }
  .overview {
    padding: 2rem 1.25rem 3rem;
  }
  .hero {
    grid-template-columns: 1fr;
    gap: 1.75rem;
    margin-bottom: 2rem;
  }
  .search-row {
    flex-direction: column;
    align-items: stretch;
    gap: 0.7rem;
  }
  .cards {
    grid-template-columns: 1fr;
  }
  .guide {
    display: block;
  }
  .chapters {
    border-right: none;
    border-bottom: 1px solid var(--line);
    padding: 1rem;
  }
  .all-guides {
    margin: 0 0 0.9rem;
  }
  .chapters h2 {
    display: inline;
    margin: 0 0 0 1rem;
    font-size: 1rem;
  }
  .chapter-menu summary {
    display: block;
    cursor: pointer;
    padding: 0.5rem 0;
    font-size: 0.85rem;
    color: var(--accent);
  }
  .chapter-list {
    display: block;
    margin: 0.7rem 0 0;
    padding: 0.25rem 0;
  }
  .chapter-list li {
    max-width: none;
  }
  .chapter {
    font-size: 0.8rem;
    padding: 0.6rem;
    margin: 0;
  }
  .chapters progress,
  .progress-label {
    display: none;
  }
  .lesson {
    padding: 1.5rem 1.1rem 2rem;
  }
  .lesson-top {
    margin-bottom: 1.25rem;
  }
  .image-card {
    padding: 0.7rem;
  }
  .image-toolbar {
    align-items: start;
    gap: 0.4rem;
  }
  .multiple-markers .hotspot {
    display: none;
  }
  .marker-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-top: 0.75rem;
    font-size: 0.85rem;
  }
  .hotspot {
    width: 28px;
    height: 28px;
    font-size: 0.7rem;
  }
  .lesson-footer {
    align-items: stretch;
  }
  .lesson-footer > div {
    justify-content: flex-end;
    flex: 1;
  }
  .lesson-footer button {
    font-size: 0.85rem;
    padding: 0.7rem;
  }
}
@media (prefers-reduced-motion: no-preference) {
  .lesson,
  .hero {
    animation: enter 0.2s ease-out;
  }
  @keyframes enter {
    from {
      opacity: 0.3;
      transform: translateY(5px);
    }
    to {
      opacity: 1;
      transform: none;
    }
  }
}