/* Casebook uses the platform's content edges and a quiet archive palette. */
:root {
  color-scheme:light;
  --bg:#f5f5ef;
  --surface:#fcfcf7;
  --ink:#292e28;
  --muted:#60665d;
  --line:#d9ddd2;
  --accent:#b54129;
  --accent-hover:#99331f;
  --on-accent:#fffaf4;
  --soft:#ebece3;
  --paper:#f5ecd8;
  --green:#426351;
  --shadow:0 15px 50px #30291309;
  font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC",sans-serif
}
:root[data-theme=dark] {
  color-scheme:dark;
  --bg:#20251f;
  --surface:#2b3129;
  --ink:#f3f2e8;
  --muted:#b9c0b2;
  --line:#454d3e;
  --accent:#f49b78;
  --accent-hover:#ffc0a4;
  --on-accent:#29251e;
  --soft:#30382c;
  --paper:#373b2f;
  --green:#a2c4ad;
  --shadow:0 15px 50px #0002
}
@media(prefers-color-scheme:dark) {
  :root:not([data-theme=light]) {
    color-scheme:dark;
    --bg:#20251f;
    --surface:#2b3129;
    --ink:#f3f2e8;
    --muted:#b9c0b2;
    --line:#454d3e;
    --accent:#f49b78;
    --accent-hover:#ffc0a4;
    --on-accent:#29251e;
    --soft:#30382c;
    --paper:#373b2f;
    --green:#a2c4ad;
    --shadow:0 15px 50px #0002
  }
}
* {
  box-sizing:border-box
}
html {
  scroll-padding-top:84px
}
body {
  margin:0;
  background:var(--bg);
  color:var(--ink);
  font-size:15px;
  line-height:1.65;
  min-height:100dvh
}
button,input {
  font:inherit;
  color:inherit
}
button {
  cursor:pointer;
  border:0
}
button,a,input {
  -webkit-tap-highlight-color:transparent;
  touch-action:manipulation
}
a {
  color:inherit;
  text-decoration:none
}
button:disabled {
  opacity:.5;
  cursor:not-allowed
}
h1,h2,h3,h4,p {
  margin:0
}
h1,h2,h3,h4 {
  line-height:1.2;
  letter-spacing:-.025em
}
p {
  color:var(--muted)
}
img {
  display:block;
  width:100%;
  object-fit:cover
}
button:focus-visible,a:focus-visible,input:focus-visible {
  outline:3px solid var(--accent);
  outline-offset:4px
}
main:focus {
  outline:none
}
.sr-only {
  position:absolute;
  width:1px;
  height:1px;
  overflow:hidden;
  clip-path:inset(50%)
}
.skip {
  position:absolute;
  top:-100px;
  left:18px;
  background:var(--surface);
  padding:12px;
  z-index:110
}
.skip:focus {
  top:12px
}
.game-header,.library,.investigation,.result {
  width:var(--ui-content-width);
  margin-inline:auto
}
.game-header {
  height:68px;
  min-height:68px;
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:20px;
  padding-block:12px;
  border-bottom:1px solid var(--line)
}
.tiny-brand {
  display:flex;
  gap:10px;
  align-items:center;
  font-size:23px;
  font-weight:700;
  line-height:1.1
}
.tiny-brand small {
  display:block;
  font-size:10px;
  font-weight:400;
  color:var(--muted);
  letter-spacing:0;
  margin-top:6px
}
.brand-glyph {
  width:38px;
  height:40px;
  display:grid;
  place-items:center;
  border:1px solid var(--accent);
  color:var(--accent);
  border-radius:8px;
  font:italic 32px Georgia,serif
}
.game-header nav {
  display:flex;
  align-items:center;
  gap:16px;
  font-size:13px
}
.library-link,.plain {
  min-height:44px;
  display:inline-flex;
  align-items:center;
  padding:10px 12px;
  background:transparent;
  border-radius:10px
}
.library-link:hover,.plain:hover {
  background:var(--soft)
}
.button {
  display:inline-flex;
  justify-content:center;
  align-items:center;
  gap:20px;
  min-height:48px;
  padding:12px 20px;
  border:1px solid var(--line);
  border-radius:10px;
  background:var(--surface);
  font-size:14px;
  font-weight:650;
  line-height:1.45
}
.button span {
  font-size:20px;
  line-height:1
}
.primary {
  background:var(--accent);
  color:var(--on-accent);
  border-color:transparent
}
.primary:hover:not(:disabled) {
  background:var(--accent-hover)
}
.eyebrow {
  font-size:11px;
  font-weight:650;
  letter-spacing:.12em
}
.library-hero {
  display:grid;
  grid-template-columns:1fr 310px;
  align-items:center;
  gap:70px;
  padding:44px 0
}
.library-hero h1 {
  font-family:Georgia,"Songti SC",serif;
  font-size:clamp(36px,4.2vw,56px);
  font-weight:400;
  line-height:1.08;
  letter-spacing:-.035em;
  margin:14px 0 20px
}
.lead {
  font-size:15px;
  max-width:52ch;
  line-height:1.8
}
.resume-card {
  background:var(--paper);
  border:1px solid var(--line);
  border-radius:14px;
  padding:24px
}
.resume-card>p {
  font-size:12px
}
.resume-card>strong {
  font-size:38px;
  line-height:1.5;
  font-weight:650;
  letter-spacing:-1px
}
.resume-card>strong>span {
  font-size:20px;
  color:var(--muted)
}
.resume-card .button {
  width:100%;
  margin-top:18px;
  justify-content:space-between
}
.resume-card>small {
  display:block;
  font-size:12px;
  color:var(--muted);
  margin-top:12px
}
.collection-heading {
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:18px;
  padding-top:28px;
  border-top:1px solid var(--line);
  margin-bottom:22px
}
.collection-heading h2 {
  font-size:26px
}
.collection-heading p {
  font-size:12px
}
.difficulty-tabs {
  display:grid;
  grid-template-columns:repeat(4,minmax(0,1fr));
  gap:12px
}
.difficulty-tabs button {
  padding:18px 20px;
  min-height:80px;
  border:1px solid var(--line);
  border-radius:12px;
  background:var(--surface);
  text-align:left
}
.difficulty-tabs button[aria-pressed=true] {
  border-color:var(--accent);
  box-shadow:inset 0 0 0 1px var(--accent);
  background:var(--soft)
}
.difficulty-tabs strong {
  display:block;
  font-size:16px;
  font-weight:650
}
.difficulty-tabs small {
  display:block;
  font-size:12px;
  color:var(--muted);
  margin-top:5px
}
.library-tools {
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:20px;
  margin-top:24px
}
.case-search {
  flex:1;
  max-width:420px
}
.case-search input {
  width:100%;
  min-height:46px;
  border:1px solid var(--line);
  background:var(--surface);
  border-radius:10px;
  padding:10px 14px;
  font-size:14px
}
.case-search input::placeholder {
  color:var(--muted)
}
.filters {
  display:flex;
  gap:4px;
  flex-wrap:wrap
}
.filters button {
  min-height:44px;
  padding:10px 13px;
  background:transparent;
  border-radius:9px;
  font-size:12px
}
.filters button[aria-pressed=true] {
  background:var(--ink);
  color:var(--bg)
}
.filters span {
  margin-left:6px
}
.results-count {
  font-size:12px;
  margin-top:18px
}
.level-section {
  margin-top:26px
}
.level-heading {
  display:flex;
  align-items:baseline;
  gap:18px;
  margin-bottom:16px
}
.level-heading h3 {
  font-size:23px
}
.level-heading p {
  font-size:13px
}
.case-list {
  display:grid;
  grid-template-columns:repeat(3,minmax(0,1fr));
  gap:16px
}
.case-file {
  display:flex;
  min-width:0;
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:12px;
  border-top:3px solid var(--line)
}
.case-file:hover {
  border-color:var(--accent)
}
.case-file.is-complete {
  border-top-color:var(--green)
}
.file-copy {
  width:100%;
  padding:22px;
  display:flex;
  flex-direction:column
}
.file-meta {
  display:flex;
  justify-content:space-between;
  gap:12px;
  color:var(--muted);
  font-size:10px
}
.file-copy h4 {
  font-size:22px;
  letter-spacing:-.025em;
  margin:20px 0 12px
}
.file-copy>p {
  font-size:13px;
  line-height:1.7;
  margin-bottom:24px
}
.file-bottom {
  display:flex;
  justify-content:space-between;
  gap:12px;
  align-items:center;
  margin-top:auto;
  font-size:11px
}
.file-bottom>span:first-child {
  color:var(--muted)
}
.file-bottom>span:last-child {
  font-weight:650;
  color:var(--accent)
}
.file-bottom b {
  font-size:16px;
  margin-left:5px;
  font-weight:400
}
.game-footer {
  display:flex;
  justify-content:space-between;
  gap:20px;
  font-size:12px;
  color:var(--muted);
  margin-top:42px;
  padding:26px 0;
  border-top:1px solid var(--line)
}
.complete-banner {
  background:var(--soft);
  border:1px solid var(--line);
  padding:24px;
  border-radius:12px;
  margin-top:24px
}
.complete-banner p {
  font-size:13px;
  margin-top:8px
}
.empty,.error {
  padding:64px 20px;
  text-align:center
}
.empty h3 {
  font-size:24px
}
.empty p {
  margin:16px auto 24px;
  max-width:46ch
}
.error {
  min-height:60vh
}
.error h1 {
  font-size:34px;
  margin-top:20px
}
.loading {
  padding:110px 24px;
  text-align:center;
  color:var(--muted)
}
.no-script {
  padding:40px
}
.case-topline {
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:16px;
  padding:16px 0;
  font-size:12px;
  color:var(--muted)
}
.back {
  display:inline-flex;
  align-items:center;
  min-height:44px;
  font-size:13px;
  font-weight:600
}
.back:hover {
  color:var(--accent)
}
.case-story {
  max-width:88ch;
  padding-bottom:26px
}
.case-story h1 {
  font:400 clamp(32px,3.5vw,44px)/1.15 Georgia,"Songti SC",serif;
  letter-spacing:-.025em;
  margin:10px 0 18px
}
.case-brief {
  font-size:15px;
  line-height:1.85;
  color:var(--ink)
}
.ground-rules {
  border-left:3px solid var(--green);
  background:var(--soft);
  padding:16px 20px;
  border-radius:0 10px 10px 0;
  margin-top:20px
}
.ground-rules strong {
  font-size:12px
}
.ground-rules p {
  font-size:13px;
  margin-top:6px
}
.investigation-nav {
  display:flex;
  gap:12px;
  flex-wrap:wrap;
  border-block:1px solid var(--line);
  padding-block:8px;
  margin-bottom:26px
}
.investigation-nav button {
  display:flex;
  align-items:center;
  gap:20px;
  min-height:44px;
  padding:10px 16px;
  border-radius:9px;
  background:transparent;
  font-size:13px;
  color:var(--muted)
}
.investigation-nav button:hover {
  background:var(--soft);
  color:var(--ink)
}
.case-layout {
  display:grid;
  grid-template-columns:minmax(0,1.25fr) minmax(340px,1fr);
  gap:32px;
  padding-bottom:52px
}
.case-main,.detective-desk {
  min-width:0;
  display:flex;
  flex-direction:column;
  gap:24px
}
.section-title {
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:16px
}
.section-title h2 {
  font-size:21px
}
.section-title>span {
  font-size:12px;
  color:var(--muted)
}
.helper {
  font-size:12px;
  margin-top:8px;
  line-height:1.8
}
.evidence-grid {
  display:grid;
  gap:12px;
  margin-top:18px
}
.evidence-card {
  padding:20px 22px;
  border:1px solid var(--line);
  border-radius:12px;
  background:var(--surface);
  text-align:left
}
.evidence-card:hover {
  border-color:var(--accent)
}
.evidence-top {
  display:flex;
  justify-content:space-between;
  font-size:10px;
  color:var(--muted);
  letter-spacing:.08em;
  margin-bottom:10px
}
.evidence-card>strong {
  font-size:15px
}
.evidence-card>p {
  font-size:14px;
  line-height:1.8;
  margin-top:8px
}
.evidence-bottom {
  display:block;
  margin-top:14px;
  font-size:11px;
  color:var(--accent)
}
.is-read .evidence-top>span {
  color:var(--green)
}
.notebook {
  background:var(--paper);
  border:1px solid var(--line);
  border-radius:12px;
  padding:24px
}
.note-scroll {
  overflow-x:auto;
  margin-top:18px;
  padding:4px
}
.notes {
  width:100%;
  border-collapse:collapse;
  table-layout:fixed;
  font-size:11px
}
.notes th {
  font-weight:600;
  font-size:10px;
  line-height:1.5;
  padding:8px 2px;
  text-align:center;
  overflow-wrap:anywhere
}
.notes th:first-child {
  width:53px;
  text-align:left
}
.notes td {
  padding:2px
}
.note-cell {
  width:100%;
  min-height:44px;
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:5px;
  font-size:20px;
  line-height:1
}
.state-1 {
  color:var(--accent);
  background:var(--soft)
}
.state-2 {
  color:var(--green);
  font-weight:750
}
.text-button {
  background:transparent;
  color:var(--muted);
  font-size:12px;
  text-decoration:underline;
  text-underline-offset:4px;
  padding:10px 0;
  min-height:44px
}
.text-button:hover {
  color:var(--accent)
}
.hint-panel {
  border:1px solid var(--line);
  border-radius:12px;
  padding:22px;
  background:var(--surface)
}
.hint-button {
  display:flex;
  justify-content:space-between;
  gap:12px;
  background:var(--soft);
  border-radius:8px;
  width:100%;
  padding:12px 16px;
  min-height:44px;
  font-size:13px;
  margin-top:16px
}
.hint-list p {
  font-size:14px;
  padding-block:14px;
  border-bottom:1px solid var(--line)
}
.hint-list strong {
  display:block;
  font-size:11px;
  margin-bottom:6px;
  color:var(--ink)
}
.answer-panel {
  border:1px solid var(--line);
  border-radius:12px;
  background:var(--surface);
  padding:24px
}
.answer-panel>h2 {
  font-size:24px
}
.answer-panel>p {
  font-size:12px;
  margin-top:10px
}
.answer-panel>.button {
  width:100%;
  margin-top:22px;
  justify-content:space-between
}
.people {
  display:grid;
  grid-template-columns:repeat(2,minmax(0,1fr));
  gap:10px;
  margin-top:18px
}
.person {
  display:grid;
  grid-template-columns:36px 1fr;
  align-items:center;
  gap:0 10px;
  text-align:left;
  padding:13px 12px;
  border:1px solid var(--line);
  border-radius:10px;
  background:var(--surface);
  position:relative;
  min-width:0
}
.person[aria-pressed=true] {
  border-color:var(--accent);
  box-shadow:inset 0 0 0 1px var(--accent);
  background:var(--soft)
}
.person-avatar {
  display:grid;
  place-items:center;
  width:34px;
  height:34px;
  border-radius:50%;
  background:var(--soft);
  color:var(--accent);
  font:22px Georgia,serif;
  grid-row:span 2
}
.person strong {
  font-size:13px
}
.person small {
  font-size:10px;
  color:var(--muted);
  line-height:1.5;
  overflow-wrap:anywhere
}
.person-check {
  position:absolute;
  right:6px;
  top:3px;
  font-size:11px;
  color:var(--accent)
}
.case-banner {
  margin:0;
  overflow:hidden;
  border-radius:12px
}
.case-banner img {
  height:auto;
  aspect-ratio:16/9
}
.case-banner figcaption {
  font-size:11px;
  padding:10px 0;
  color:var(--muted)
}
.mobile-submit {
  display:none
}
.result {
  padding:26px 0 60px
}
.result-grid {
  display:grid;
  grid-template-columns:1fr 1.15fr;
  gap:60px;
  margin-top:30px
}
.result-letter {
  padding:24px 0
}
.solved-stamp {
  display:inline-flex;
  flex-direction:column;
  gap:4px;
  color:var(--green);
  border:1px solid var(--green);
  border-radius:8px;
  padding:10px 18px;
  font-size:13px;
  letter-spacing:.08em;
  margin-bottom:26px
}
.solved-stamp small {
  font-size:10px
}
.result-letter h1 {
  font:400 46px/1.15 Georgia,"Songti SC",serif;
  margin:12px 0 24px
}
.result-answer {
  font-size:20px;
  color:var(--ink)
}
.ending {
  font-size:15px;
  margin-top:20px;
  line-height:1.85
}
.result-stats {
  display:flex;
  gap:48px;
  padding-block:24px;
  border-block:1px solid var(--line);
  margin-block:26px
}
.result-stats>span {
  display:flex;
  flex-direction:column;
  font-size:12px;
  color:var(--muted)
}
.result-stats strong {
  font-size:28px;
  color:var(--ink)
}
.result-letter>.text-button {
  display:block;
  margin-top:16px
}
.solution {
  padding:28px;
  background:var(--surface);
  border:1px solid var(--line);
  border-radius:14px
}
.solution h2 {
  font-size:24px
}
.solution-art {
  border-radius:10px;
  overflow:hidden;
  margin-bottom:24px
}
.solution-art img {
  aspect-ratio:16/9;
  height:auto
}
.solution ol {
  padding-left:22px;
  margin-block:24px
}
.solution li {
  padding:0 0 20px 10px;
  font-size:14px;
  line-height:1.85;
  color:var(--muted)
}
.solution li::marker {
  color:var(--green);
  font-weight:600
}
dialog {
  border:1px solid var(--line);
  background:var(--surface);
  color:var(--ink);
  padding:32px;
  border-radius:16px;
  max-width:min(540px,calc(100% - 32px));
  max-height:calc(100dvh - 40px);
  box-shadow:0 24px 90px #0003
}
dialog::backdrop {
  background:#13251dcc
}
dialog h2 {
  font-size:26px;
  padding-right:24px;
  margin:12px 0 20px
}
dialog h3 {
  font-size:18px;
  margin-block:18px 10px
}
dialog p {
  font-size:14px;
  line-height:1.85
}
.dialog-close {
  position:absolute;
  right:8px;
  top:8px;
  font-size:24px
}
.dialog-actions {
  display:flex;
  gap:10px;
  flex-wrap:wrap;
  margin-top:24px
}
.dialog-actions .button {
  flex:1;
  font-size:13px;
  white-space:nowrap;
  padding-inline:16px
}
.enlarged-clue {
  font:23px/1.65 Georgia,"Songti SC",serif;
  color:var(--ink);
  margin:20px 0 28px
}
.danger {
  color:var(--accent);
  margin-top:12px
}
.toast {
  position:fixed;
  bottom:22px;
  left:50%;
  transform:translate(-50%,12px);
  background:var(--ink);
  color:var(--bg);
  padding:14px 22px;
  border-radius:10px;
  font-size:13px;
  max-width:min(590px,calc(100% - 32px));
  z-index:95;
  opacity:0;
  pointer-events:none
}
.toast.visible {
  opacity:1;
  transform:translate(-50%,0)
}
@media(max-width:1000px) {
  .library-hero {
    gap:32px;
    grid-template-columns:1fr 280px
  }
  .case-list {
    grid-template-columns:repeat(2,minmax(0,1fr))
  }
  .case-layout {
    gap:24px;
    grid-template-columns:1fr 1fr
  }
  .notebook,.answer-panel {
    padding:20px
  }
  .person {
    grid-template-columns:1fr
  }
  .person-avatar {
    display:none
  }
  .difficulty-tabs button {
    padding:16px
  }
  .result-grid {
    gap:32px
  }
}
@media(max-width:740px) {
  .game-header {
    height:62px;
    min-height:62px;
    padding-block:10px
  }
  .tiny-brand {
    font-size:21px
  }
  .game-header nav {
    gap:6px
  }
  .library-link {
    font-size:12px
  }
  .library-hero {
    grid-template-columns:1fr;
    gap:24px;
    padding-block:30px
  }
  .library-hero h1 {
    font-size:42px
  }
  .lead {
    font-size:14px
  }
  .resume-card {
    padding:20px
  }
  .resume-card>strong {
    font-size:32px
  }
  .resume-card .button {
    margin-top:12px
  }
  .difficulty-tabs {
    grid-template-columns:1fr 1fr;
    gap:10px
  }
  .difficulty-tabs button {
    min-height:74px;
    padding:14px 16px
  }
  .difficulty-tabs strong {
    font-size:15px
  }
  .difficulty-tabs small {
    font-size:11px
  }
  .collection-heading {
    padding-top:24px
  }
  .collection-heading h2 {
    font-size:24px
  }
  .collection-heading p {
    font-size:11px
  }
  .library-tools {
    flex-direction:column;
    align-items:stretch;
    gap:12px
  }
  .case-search {
    max-width:none
  }
  .filters button {
    padding-inline:12px
  }
  .level-heading {
    display:block
  }
  .level-heading p {
    margin-top:8px
  }
  .case-list {
    grid-template-columns:1fr;
    gap:14px
  }
  .file-copy {
    padding:20px
  }
  .file-copy h4 {
    font-size:23px;
    margin-top:16px
  }
  .file-copy>p {
    margin-bottom:20px
  }
  .game-footer {
    flex-direction:column;
    gap:10px
  }
  .case-topline {
    flex-wrap:wrap;
    gap:4px 12px
  }
  .case-topline>span:last-child {
    display:none
  }
  .case-story h1 {
    font-size:34px
  }
  .case-brief {
    font-size:14px
  }
  .ground-rules {
    padding:14px 16px
  }
  .investigation-nav {
    gap:0
  }
  .investigation-nav button {
    padding-inline:11px;
    font-size:12px;
    gap:10px
  }
  .case-layout {
    grid-template-columns:1fr;
    gap:24px
  }
  .notebook,.answer-panel {
    padding:22px
  }
  .people {
    grid-template-columns:1fr 1fr
  }
  .person {
    grid-template-columns:34px 1fr;
    padding:13px 10px
  }
  .person-avatar {
    display:grid
  }
  .investigation {
    padding-bottom:88px
  }
  .mobile-submit {
    position:fixed;
    bottom:0;
    left:0;
    right:0;
    z-index:50;
    display:flex;
    justify-content:space-between;
    align-items:center;
    gap:16px;
    padding:12px 18px max(12px,env(safe-area-inset-bottom));
    background:var(--surface);
    border-top:1px solid var(--line)
  }
  .mobile-submit>span {
    font-size:11px;
    max-width:44%;
    line-height:1.5;
    color:var(--muted)
  }
  .mobile-submit .button {
    font-size:12px;
    padding:12px 16px;
    flex-shrink:0
  }
  .toast {
    bottom:90px;
    font-size:12px;
    width:calc(100% - 32px)
  }
  .result-grid {
    grid-template-columns:1fr;
    gap:24px;
    margin-top:8px
  }
  .result-letter h1 {
    font-size:40px
  }
  .solution {
    padding:22px
  }
  dialog {
    padding:28px 22px
  }
  .dialog-actions .button {
    padding-inline:12px;
    font-size:12px
  }
}
@media(prefers-reduced-motion:no-preference) {
  .button,.case-file,.person {
    transition:background-color .16s,border-color .16s
  }
  .toast {
    transition:opacity .18s,transform .18s
  }
}
.tiny-brand {
  min-height:44px
}
.note-scroll-hint {
  display:none
}
@media(max-width:740px) {
  .note-scroll-hint {
    display:block;
    font-size:11px;
    margin-top:10px
  }
}