* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 2rem;
}
body {
  margin: 0;
  background: #fafbfc;
  color: #202733;
  font-family:
    "Source Sans 3",
    "Segoe UI",
    Arial,
    sans-serif;
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}
a {
  color: inherit;
  text-underline-offset: .2em;
}
button,
input,
select {
  font: inherit;
}
button,
a,
input,
select,
summary {
  -webkit-tap-highlight-color: transparent;
}
button,
select,
summary {
  cursor: pointer;
}
button {
  color: inherit;
}
button:disabled {
  cursor: default;
  opacity: .5;
}
a:focus-visible,
button:focus-visible,
input:focus-visible,
select:focus-visible,
summary:focus-visible {
  outline: 3px solid #3157ff;
  outline-offset: 5px;
}
h1,
h2,
h3,
p {
  margin: 0;
}
h1,
h2,
h3 {
  line-height: 1.12;
  font-weight: 600;
  letter-spacing: -.045em;
}
h1 {
  font-size: clamp(2.9rem, 5.6vw, 5rem);
}
h2 {
  font-size: clamp(2rem, 3.2vw, 3rem);
}
h3 {
  font-size: 1.45rem;
  letter-spacing: -.025em;
}
p + p {
  margin-top: 1rem;
}
button {
  border: 0;
}
svg {
  max-width: 100%;
}
[hidden] {
  display: none !important;
}
.wrap {
  max-width: 1280px;
  margin-inline: auto;
  padding-inline: 3rem;
}
.eyebrow {
  font-size: .75rem;
  font-weight: 650;
  letter-spacing: .12em;
  line-height: 1.5;
}
.muted {
  color: #56667d;
}
.lead {
  font-size: 1.3rem;
  line-height: 1.6;
  max-width: 44rem;
}
.skip {
  position: fixed;
  top: -100px;
  left: 1rem;
  z-index: 100;
  background: white;
  padding: .75rem 1rem;
}
.skip:focus {
  top: 1rem;
}
.draft-bar {
  background: #e9eef6;
  color: #425269;
  font-size: .75rem;
  text-align: center;
  padding: .32rem 1rem;
  letter-spacing: .055em;
}
.draft-bar span {
  padding-inline: .35rem;
}
.site-header {
  height: 96px;
  padding-inline: 3rem;
  max-width: 1440px;
  margin: auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 2rem;
}
.wordmark {
  display: flex;
  gap: .75rem;
  align-items: center;
  text-decoration: none;
  white-space: nowrap;
  line-height: 1.2;
  font-size: 1.25rem;
  font-weight: 600;
  letter-spacing: -.025em;
}
.wordmark svg {
  width: 38px;
  height: 36px;
  flex: none;
  color: var(--blue);
}
.wordmark b {
  font-weight: 400;
  color: var(--blue);
}
.wordmark small {
  display: block;
  font-weight: 500;
  font-size: .75rem;
  letter-spacing: .15em;
  margin-top: .45rem;
  color: #56667d;
}
.site-header nav {
  display: flex;
  gap: 2.1rem;
  align-items: center;
  font-size: .9375rem;
  font-weight: 500;
}
.site-header nav a {
  text-decoration: none;
  padding: .5rem 0;
  border-bottom: 2px solid transparent;
}
.site-header nav a:hover,
.site-header nav a[aria-current] {
  color: var(--blue);
  border-color: var(--blue);
}
.menu-toggle {
  display: none;
  background: transparent;
  padding: .65rem;
  font-size: .9375rem;
}
.button {
  display: inline-flex;
  justify-content: center;
  align-items: center;
  gap: 1.5rem;
  border: 1px solid transparent;
  border-radius: 3px;
  min-height: 50px;
  padding: .78rem 1.3rem;
  text-decoration: none;
  font-size: .9375rem;
  font-weight: 600;
  line-height: 1.4;
  transition: background .16s, transform .16s;
}
.button span {
  font-size: 1.25rem;
  font-weight: 400;
  line-height: 1;
}
.button:hover {
  transform: translateY(-2px);
}
.primary {
  background: var(--blue);
  color: #fff;
}
.primary:hover {
  background: #2a4dd8;
}
.secondary {
  border-color: #cbd2de;
  background: transparent;
  color: #202733;
}
.secondary:hover {
  background: #edf1f8;
}
.secondary.dark {
  border-color: #566172;
  color: #f5f7ff;
}
.secondary.dark:hover {
  background: #2a3341;
}
.actions {
  display: flex;
  gap: 1rem;
  flex-wrap: wrap;
}
.text-link {
  display: inline-flex;
  align-items: center;
  gap: 1.5rem;
  font-size: .9375rem;
  font-weight: 600;
  text-decoration: none;
}
.text-link:hover {
  text-decoration: underline;
}
.text-link span {
  font-size: 1.25rem;
}
.hero {
  background: #141920;
  display: grid;
  grid-template-columns: 1fr 1fr;
  max-width: 1440px;
  margin: auto;
  color: #f4f6fc;
  min-height: 680px;
}
.hero-copy {
  padding: 4.7rem 1.5rem 2rem 4.5rem;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
}
.hero-copy .eyebrow {
  color: #bfc9dd;
  display: flex;
  gap: .65rem;
  align-items: center;
}
.small-rule {
  width: 25px;
  height: 2px;
  background: var(--blue-light);
}
.hero h1 {
  font-size: clamp(3.4rem, 5.5vw, 5.5rem);
  line-height: 1.045;
  letter-spacing: -.053em;
  margin: 1.65rem 0;
}
.hero h1 em {
  font-style: normal;
  color: var(--blue-light);
}
.hero-copy > p {
  color: #bfc8d8;
  font-size: 1.14rem;
  max-width: 22rem;
  margin-bottom: 2.1rem;
  line-height: 1.6;
}
.hero-copy .primary {
  background: #b2c2ff;
  color: #12204d;
}
.hero-copy .primary:hover {
  background: #ccd6ff;
}
.hero-footnote {
  margin-top: auto;
  padding-top: 3.2rem;
  display: flex;
  flex-wrap: wrap;
  gap: .5rem 2rem;
  font-size: .75rem;
  letter-spacing: .08em;
  color: #8f9cb2;
}
.hero-footnote span:last-child {
  display: none;
}
.hero-object {
  margin: 2rem 2rem 2rem .7rem;
  border: 1px solid #38404d;
  background:
    radial-gradient(
      ellipse at 60% 28%,
      #2a3546 0%,
      #1b222e 53%,
      #171d26 100%);
  position: relative;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.object-heading {
  padding: 1.4rem 1.5rem;
  display: flex;
  justify-content: space-between;
  color: #a8b6ca;
  font-size: .75rem;
  letter-spacing: .13em;
}
.model-stage {
  position: relative;
  flex: 1;
  min-height: 365px;
  overflow: hidden;
  touch-action: pan-y;
}
.model-stage canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}
.drawing-fallback {
  position: absolute;
  inset: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #b0c1ff;
}
.drawing-fallback svg {
  width: 100%;
  height: 100%;
}
.model-label {
  position: absolute;
  left: 1.5rem;
  bottom: .75rem;
  right: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  color: #9daec6;
  font-size: .75rem;
  letter-spacing: .1em;
  line-height: 1.6;
  pointer-events: none;
}
.axis-label {
  border: 1px solid #53647d;
  padding: .3rem .6rem;
  font-family: monospace;
}
.model-toolbar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: .6rem;
  padding: 1rem 1.2rem .45rem;
}
.segmented {
  display: flex;
  border: 1px solid #536074;
  border-radius: 3px;
  padding: 3px;
  background: #171e29;
}
.segmented button {
  background: transparent;
  color: #c1cbe0;
  font-size: .875rem;
  padding: .55rem .65rem;
  border-radius: 2px;
  min-height: 42px;
}
.segmented button[aria-pressed=true] {
  background: #e9edfa;
  color: #1c2949;
}
.motion-tools {
  display: flex;
  gap: .6rem;
}
.motion-tools button {
  background: transparent;
  color: #bbc8e0;
  border-bottom: 1px solid #788498;
  font-size: .875rem;
  min-height: 42px;
  padding: .35rem;
}
.model-status {
  font-size: .875rem;
  line-height: 1.5;
  color: #bbcae0;
  margin: .3rem 1.4rem .5rem;
  min-height: 2.5em;
}
.model-disclaimer {
  color: #92a2b9;
  font-size: .75rem;
  line-height: 1.5;
  margin: 0 1.4rem 1.25rem !important;
}
.method-section {
  padding-block: 5.5rem;
}
.section-intro {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 4rem;
  margin-bottom: 2.8rem;
}
.section-intro .eyebrow {
  color: #56667d;
  margin-bottom: 1rem;
}
.section-intro > p {
  max-width: 27rem;
  color: #56667d;
}
.method-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2.5rem;
  border-top: 1px solid #ced6e1;
  padding-top: 2rem;
}
.method-number {
  display: block;
  font-family: monospace;
  font-size: .875rem;
  color: var(--blue);
  margin-bottom: 1.15rem;
}
.method-grid h3 {
  margin-bottom: .75rem;
}
.method-grid p {
  color: #56667d;
  max-width: 21rem;
}
.book-band {
  background: #eaf0f8;
  padding-block: 4rem;
  border-block: 1px solid #dce4ee;
}
.book-band-inner {
  display: grid;
  grid-template-columns: .85fr 1fr;
  gap: 5rem;
  align-items: center;
}
.book-tile {
  background: #2643a7;
  color: white;
  padding: 2.5rem;
  border-left: 8px solid #173187;
  max-width: 430px;
}
.book-tile .eyebrow {
  color: #c3d0ff;
  font-size: .75rem;
}
.book-tile h2 {
  font-size: 3rem;
  margin: 3rem 0 1rem;
}
.book-tile p {
  font-size: 1rem;
  color: #cfdaff;
}
.tile-line {
  height: 1px;
  background: #839ee1;
  margin: 3rem 0 1.25rem;
}
.book-tile > span:last-child {
  font-size: .75rem;
  letter-spacing: .1em;
}
.book-pitch .eyebrow {
  color: #56667d;
  margin-bottom: 1.25rem;
}
.book-pitch p {
  margin-top: 1.3rem;
}
.book-pitch .button {
  margin-top: 1.8rem;
}
.guide-section {
  padding-block: 5.5rem;
}
.section-heading {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 2rem;
  margin-bottom: 2rem;
}
.section-heading .eyebrow {
  color: #64738a;
  margin-bottom: .75rem;
}
.guide-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}
.guide-card {
  border: 1px solid #d5dce6;
  background: white;
  border-radius: 4px;
  overflow: hidden;
  transition: box-shadow .2s;
}
.guide-card:hover {
  box-shadow: 0 9px 28px #24334b0a;
}
.guide-visual {
  height: 170px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  background-color: #edf1f8;
  color: #49609b;
  background-image:
    linear-gradient(#b3bed522 1px, transparent 1px),
    linear-gradient(
      90deg,
      #b3bed522 1px,
      transparent 1px);
  background-size: 22px 22px;
}
.guide-visual.visual-1 {
  color: #9bb2ff;
  background-color: #202b41;
  background-image:
    linear-gradient(#91a3c011 1px, transparent 1px),
    linear-gradient(
      90deg,
      #91a3c011 1px,
      transparent 1px);
}
.guide-visual.visual-2 {
  background-color: #eef0ed;
  color: #536253;
}
.guide-visual svg {
  max-height: 130px;
  width: 85%;
}
.keycap {
  background: white;
  border: 1px solid #a8b7d1;
  border-bottom: 4px solid #a8b7d1;
  border-radius: 6px;
  padding: .7rem 1.25rem;
  font-size: 2rem;
  line-height: 1.3;
  box-shadow: 0 6px 12px #485f7d12;
}
.key-then {
  font-size: .875rem;
  color: #687993;
}
.keycap.enter {
  font-size: 1.7rem;
}
.card-content {
  padding: 1.5rem;
}
.card-meta {
  display: flex;
  justify-content: space-between;
  gap: .6rem;
  flex-wrap: wrap;
  font-size: .75rem;
  line-height: 1.5;
  color: #66758c;
}
.card-content h3 {
  margin: 1rem 0;
  font-size: 1.5rem;
}
.card-content h3 a {
  text-decoration: none;
}
.card-content h3 a:hover {
  text-decoration: underline;
}
.card-content p {
  color: #56667d;
  font-size: 1rem;
}
.card-content > .text-link {
  margin-top: 1.3rem;
  color: var(--blue);
}
.resource-banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 3rem;
  background: #edf1f7;
  border-top: 1px solid #d5dfe9;
  margin-bottom: 5rem;
  padding-block: 2.7rem;
}
.resource-banner .eyebrow {
  color: #56667d;
  margin-bottom: .65rem;
}
.resource-banner h2 {
  font-size: 2rem;
}
.resource-banner p {
  margin-top: .75rem;
  color: #56667d;
}
.resource-banner .button {
  flex: none;
}
footer {
  border-top: 1px solid #d4dde7;
  background: #f3f5f8;
  padding: 2.6rem 3rem 1.5rem;
}
.footer-top,
.footer-bottom {
  max-width: 1280px;
  margin: auto;
  display: flex;
  justify-content: space-between;
  gap: 2rem;
  align-items: center;
}
.footer-top > p {
  font-size: .875rem;
  color: #607086;
  max-width: 18rem;
}
.footer-top > a:last-child {
  font-size: .875rem;
  color: #4a5a72;
}
.footer-bottom {
  padding-top: 2rem;
  margin-top: 2rem;
  border-top: 1px solid #d6dde8;
  font-size: .75rem;
  color: #56667d;
  flex-wrap: wrap;
}
.breadcrumb {
  display: flex;
  gap: .7rem;
  flex-wrap: wrap;
  font-size: .875rem;
  color: #63738c;
  padding-top: 2rem;
  margin-bottom: 2.5rem;
}
.breadcrumb a {
  text-decoration: none;
}
.breadcrumb a:hover {
  text-decoration: underline;
}
.page-heading {
  padding-bottom: 3.5rem;
  padding-top: 0;
}
.page-heading > .eyebrow {
  color: #5b7199;
  margin-bottom: 1.25rem;
}
.page-heading h1 {
  margin-bottom: 1.65rem;
  max-width: 59rem;
}
.page-heading > .muted {
  margin-top: .75rem;
}
.status-label {
  display: inline-block;
  border: 1px solid #c0cada;
  color: #4d6080;
  font-size: .75rem;
  letter-spacing: .055em;
  font-weight: 600;
  border-radius: 2px;
  padding: .3rem .6rem;
  white-space: normal;
}
.book-heading-grid {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 4rem;
  align-items: center;
  margin-top: 1.75rem;
}
.subtitle {
  display: block;
  font-size: .42em;
  line-height: 1.3;
  font-weight: 400;
  letter-spacing: -.015em;
  margin-top: 1rem;
  color: #65748a;
}
.book-heading-grid .lead {
  margin-bottom: 1rem;
}
.book-heading-grid .actions {
  margin-top: 2rem;
}
.availability {
  font-size: .875rem;
  color: #66758c;
  margin-top: 1.5rem !important;
}
.book-drawing {
  background: #e9eef6;
  padding: 1.6rem;
  color: #415d9f;
  min-width: 0;
  border: 1px solid #d2ddec;
}
.book-drawing > span {
  font-size: .75rem;
  letter-spacing: .07em;
  display: block;
  text-align: center;
}
.ruled-section {
  padding-block: 3.5rem;
  border-top: 1px solid #d5dce6;
}
.contents-list > div {
  display: grid;
  grid-template-columns: 3rem 1fr 1.2fr;
  gap: 2rem;
  padding: 1.5rem 0;
  border-top: 1px solid #d5dce6;
  align-items: center;
}
.contents-list > div > span {
  font-family: monospace;
  color: #56667d;
}
.contents-list p {
  color: #56667d;
  font-size: 1rem;
}
.two-column {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
}
.section-space {
  padding-block: 3rem 5rem;
}
.two-column p {
  margin-top: 1.3rem;
  color: #56667d;
}
.plain-panel {
  padding: 2rem;
  background: #edf1f8;
  border-top: 2px solid #7290d6;
}
.plain-panel .eyebrow {
  margin-bottom: 1rem;
}
.plain-panel h3 {
  font-size: 1.8rem;
}
.plain-panel .text-link {
  margin-top: 1.5rem;
}
.check-list {
  list-style: none;
  padding: 0;
  margin: 1.5rem 0;
}
.check-list li {
  padding: .8rem 0 .8rem 1.5rem;
  position: relative;
  border-bottom: 1px solid #d9e0ed;
  font-size: 1rem;
}
.check-list li:before {
  content: "\2713";
  position: absolute;
  left: 0;
  color: #4f6bc6;
}
.reading-note {
  background: #eef2f9;
  border-left: 3px solid var(--blue);
  padding-block: 2.3rem;
  margin-bottom: 5rem;
}
.reading-note h2 {
  font-size: 2rem;
  margin-bottom: 1rem;
}
.reading-note p {
  max-width: 55rem;
  color: #55667e;
}
.reading-note .button {
  margin-top: 1.5rem;
}
.reading-note .eyebrow {
  margin-bottom: 1rem;
}
.library-section {
  padding-bottom: 6rem;
}
.search-row {
  display: flex;
  gap: 1.5rem;
  align-items: flex-end;
  border-top: 1px solid #d5dce6;
  padding-top: 2rem;
}
.search-box {
  flex: 1;
}
.search-box span,
.filter-box {
  font-size: .875rem;
  font-weight: 600;
}
.search-box input,
select,
input[type=number] {
  display: block;
  width: 100%;
  border: 1px solid #b7c3d6;
  background: white;
  color: #29364b;
  border-radius: 3px;
  padding: .8rem 1rem;
  margin-top: .5rem;
  min-height: 50px;
}
.filter-box {
  min-width: 235px;
}
.result-count {
  font-size: .875rem;
  color: #65748b;
  margin-block: 1.3rem;
}
.empty-state {
  padding: 3rem;
  border: 1px solid #d5dce6;
  text-align: center;
}
.empty-state p {
  margin: 1rem;
}
.article-heading {
  padding-bottom: 3rem;
  border-bottom: 1px solid #dbe2ec;
}
.article-heading .eyebrow {
  color: #5b7199;
  margin-bottom: 1.2rem;
}
.dot-separator {
  margin-inline: .6rem;
}
.article-heading h1 {
  font-size: clamp(2.8rem, 5.5vw, 4.7rem);
  margin-bottom: 1.4rem;
}
.article-note {
  font-size: .875rem;
  color: #64758d;
  margin-top: 1.5rem;
}
.article-layout {
  display: grid;
  grid-template-columns: 230px minmax(0, 730px);
  gap: 4rem;
  justify-content: space-between;
  padding-block: 3.5rem 5rem;
}
.article-aside {
  align-self: start;
  position: sticky;
  top: 2rem;
}
.article-aside .eyebrow {
  color: #56667d;
  margin-bottom: 1rem;
}
.article-aside nav {
  display: flex;
  flex-direction: column;
  border-left: 1px solid #ccd5e4;
}
.article-aside nav a {
  padding: .6rem 1rem;
  text-decoration: none;
  color: #62718a;
  font-size: .9375rem;
}
.article-aside nav a:hover {
  color: var(--blue);
  background: #edf1f8;
}
.article-aside > .text-link {
  margin-top: 1.5rem;
  font-size: .875rem;
}
.reading-content section {
  margin-bottom: 3rem;
  scroll-margin-top: 2rem;
}
.reading-content h2 {
  font-size: 1.85rem;
  margin-bottom: 1.2rem;
  letter-spacing: -.03em;
}
.reading-content p {
  line-height: 1.8;
  color: #42516a;
}
.reading-content strong {
  color: #22324d;
  font-weight: 650;
}
kbd {
  display: inline-block;
  border: 1px solid #c7d0dd;
  border-bottom-width: 2px;
  border-radius: 3px;
  padding: 0 .35rem;
  font-size: .9em;
  background: #f1f4f9;
}
.command-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem;
  background: #edf1f7;
  border: 1px solid #cbd6e7;
  padding: 1rem 1.3rem;
  margin: 1.4rem 0;
}
.command-strip > span {
  font-size: .875rem;
  color: #647793;
}
.command-strip code {
  font-weight: 600;
  color: #2c4daa;
}
.takeaway {
  border-left: 3px solid #627fd3;
  background: #eef2fa;
  padding: 1.3rem 1.5rem;
  margin-top: 1.75rem;
}
.takeaway > strong {
  font-size: .875rem;
}
.takeaway p {
  margin-top: .4rem;
  font-size: 1rem;
}
.source-notes {
  border-top: 1px solid #d7deea;
  padding-top: 1.8rem;
}
.source-notes h2 {
  font-size: 1.25rem;
}
.source-notes p,
.source-notes li {
  font-size: .875rem;
}
.source-notes ul {
  padding-left: 1.3rem;
}
.source-notes li {
  margin: .7rem 0;
}
.source-notes a {
  color: #3156ad;
}
.article-next {
  border-top: 1px solid #cad4e5;
  padding-top: 2rem;
}
.article-next .eyebrow {
  color: #56667d;
}
.article-next h2 {
  margin-top: .8rem;
}
.concept-demo {
  border: 1px solid #bfcde0;
  background: #f5f7fc;
  border-radius: 4px;
  overflow: hidden;
  margin: 1.5rem 0;
}
.demo-top {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: .8rem;
  background: #e7edf8;
  padding: 1rem 1.25rem;
  align-items: center;
  font-size: .875rem;
  color: #40557c;
}
.demo-grid {
  display: grid;
  grid-template-columns: 1.05fr 1fr;
  gap: 1rem;
  padding: 1.25rem;
}
.plot {
  align-self: center;
  min-width: 0;
}
.plot svg {
  width: 100%;
  display: block;
}
.demo-grid form {
  min-width: 0;
}
.demo-grid fieldset {
  border: 0;
  padding: 0;
  margin: 0 0 1rem;
}
.demo-grid legend {
  font-size: .875rem;
  font-weight: 600;
  margin-bottom: .75rem;
}
.radio-choice {
  display: flex;
  align-items: center;
  gap: .5rem;
  font-size: .875rem;
  padding: .4rem 0;
  min-height: 42px;
}
.radio-choice input {
  accent-color: var(--blue);
  width: 18px;
  height: 18px;
  flex: none;
}
.number-inputs {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.25rem;
}
.number-inputs label {
  flex: 1;
  min-width: 0;
  font-size: .875rem;
}
.number-inputs input {
  width: 100%;
  padding: .5rem .65rem;
}
.demo-grid .button {
  width: 100%;
  font-size: .875rem;
  padding: .75rem;
}
.text-button {
  display: block;
  background: transparent;
  text-decoration: underline;
  font-size: .875rem;
  color: #546993;
  padding: .75rem 0;
  text-align: left;
  min-height: 44px;
}
.demo-result {
  padding: 1.25rem;
  border-top: 1px solid #c7d3e5;
  font-size: .9375rem;
  background: #eaf0fc;
  line-height: 1.7;
}
.demo-result[data-state=error] {
  background: #fff0ed;
  color: #8c382b;
}
.demo-result[data-state=success] {
  background: #e6f0e9;
  color: #28503e;
}
.check-figure {
  border: 1px solid #cfdaea;
  padding: 1rem;
  margin-top: 1.5rem;
  color: #405d9e;
  background: #f2f5fa;
}
.resource-section {
  padding-bottom: 2rem;
}
.resource-filter {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  border-top: 1px solid #d0dbe9;
  padding-block: 1.5rem;
  margin-bottom: 1rem;
}
.resource-filter label {
  font-weight: 600;
  font-size: .9375rem;
}
.resource-filter select {
  width: auto;
  margin: 0;
  min-width: 340px;
}
.resource-filter p {
  margin-left: auto;
  color: #65748b;
  font-size: .875rem;
}
.resource-list {
  margin-bottom: 3rem;
}
.resource-card {
  display: flex;
  gap: 1.75rem;
  padding: 2rem 0;
  border-bottom: 1px solid #d8e0eb;
  align-items: flex-start;
}
.file-icon {
  width: 58px;
  min-height: 75px;
  border: 1px solid #a7b8d6;
  border-top: 4px solid #8ba2d9;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #4f69a0;
  font-size: .75rem;
  flex: none;
  border-radius: 2px;
  background: #eff3fb;
}
.resource-main {
  flex: 1;
  min-width: 0;
}
.resource-main h2 {
  font-size: 1.5rem;
  margin: .45rem 0 .7rem;
}
.resource-main p {
  font-size: 1rem;
  color: #66758b;
  max-width: 42rem;
}
.file-meta {
  font-size: .75rem;
  margin-bottom: 0;
  display: flex;
  gap: 1rem 2rem;
  flex-wrap: wrap;
  overflow-wrap: anywhere;
}
.file-meta > div {
  display: flex;
  gap: .5rem;
}
.file-meta dt {
  color: #536886;
}
.file-meta dd {
  margin: 0;
  color: #596980;
}
.resource-action {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 1rem;
  min-width: 180px;
}
.resource-action .button {
  font-size: .875rem;
  min-height: 44px;
}
.resource-action p {
  font-size: .875rem;
  color: #64758f;
  text-align: right;
}
.status-label.available {
  color: #315884;
  border-color: #bacce5;
  background: #edf3fc;
}
.compact {
  padding-inline: 2rem;
}
.compact p {
  font-size: 1rem;
}
.faq-section {
  padding-block: 1rem 5rem;
}
.faq-section > .section-heading > span {
  color: #56667d;
  font-size: .875rem;
}
.faq-section details {
  border-bottom: 1px solid #d1dbe9;
}
.faq-section summary {
  list-style: none;
  font-weight: 600;
  font-size: 1.1rem;
  padding: 1.3rem 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}
.faq-section summary::-webkit-details-marker {
  display: none;
}
.faq-section summary span {
  font-size: 1.5rem;
  color: #7286ab;
}
.faq-section details[open] summary span {
  transform: rotate(45deg);
}
.faq-section details p {
  color: #5f708a;
  max-width: 53rem;
  margin: 0 2rem 1.5rem 0;
}
.contact-placeholder {
  display: flex;
  gap: 2rem;
  border-top: 1px solid #cbd7e9;
  padding-top: 1.5rem;
  margin-top: 1.5rem;
  font-size: .9375rem;
  flex-wrap: wrap;
}
.contact-placeholder span {
  color: #56667d;
}
.error-page {
  min-height: 60vh;
  padding-top: 5rem;
}
.error-page .actions {
  margin-top: 2rem;
}
@media (min-width: 1440px) {
  .hero {
    margin-inline: auto;
    border-radius: 4px;
  }
  .site-header {
    padding-inline: 4.5rem;
  }
}
@media (max-width: 1100px) {
  .wrap {
    padding-inline: 2rem;
  }
  .site-header {
    padding-inline: 2rem;
  }
  .site-header nav {
    gap: 1.4rem;
  }
  .hero-copy {
    padding: 3.5rem 1.3rem 2rem 2rem;
  }
  .hero-object {
    margin: 1.5rem 1.5rem 1.5rem 0;
  }
  .hero h1 {
    font-size: 4.25rem;
  }
  .model-toolbar {
    justify-content: center;
  }
  .model-stage {
    min-height: 340px;
  }
  .book-band-inner {
    gap: 3rem;
  }
  .article-layout {
    grid-template-columns: 190px minmax(0, 1fr);
    gap: 2rem;
  }
  .demo-grid {
    grid-template-columns: 1fr;
  }
  .plot svg {
    max-height: 330px;
  }
  .resource-card {
    gap: 1.2rem;
  }
  .guide-grid {
    gap: 1rem;
  }
  .card-content {
    padding: 1.2rem;
  }
  .card-meta {
    font-size: .75rem;
  }
  .card-content h3 {
    font-size: 1.35rem;
  }
}
@media (max-width: 820px) {
  .site-header {
    height: 82px;
    position: relative;
  }
  .menu-toggle {
    display: flex;
    align-items: center;
    gap: .7rem;
  }
  .site-header nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #fafbfc;
    padding: 1rem 2rem 1.5rem;
    z-index: 20;
    box-shadow: 0 8px 15px #1d2e4315;
    align-items: stretch;
    gap: .25rem;
  }
  .site-header nav.is-open {
    display: flex;
    flex-direction: column;
  }
  .site-header nav a {
    padding: .7rem .5rem;
  }
  .hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }
  .hero-copy {
    padding: 3.5rem 2rem 2.3rem;
  }
  .hero h1 {
    font-size: clamp(3.25rem, 8vw, 4.8rem);
    margin: 1.3rem 0;
  }
  .hero h1 br.desktop-break {
    display: none;
  }
  .hero-copy > p {
    max-width: 28rem;
  }
  .hero-footnote {
    padding-top: 2rem;
  }
  .hero-object {
    margin: 0 2rem 2rem;
  }
  .model-stage {
    height: 420px;
    min-height: 420px;
    flex: auto;
  }
  .model-toolbar {
    justify-content: space-between;
  }
  .model-status {
    min-height: auto;
  }
  .method-section,
  .guide-section {
    padding-block: 3.5rem;
  }
  .section-intro {
    gap: 2rem;
    align-items: flex-start;
  }
  .section-intro > p {
    max-width: 22rem;
  }
  .method-grid {
    gap: 1.5rem;
  }
  .book-band-inner {
    gap: 2rem;
  }
  .book-tile {
    padding: 1.7rem;
  }
  .book-tile h2 {
    font-size: 2.3rem;
  }
  .book-pitch h2 {
    font-size: 2rem;
  }
  .guide-grid {
    grid-template-columns: 1fr;
  }
  .guide-card {
    display: grid;
    grid-template-columns: 210px 1fr;
  }
  .guide-visual {
    height: 100%;
    min-height: 225px;
  }
  .card-content h3 {
    font-size: 1.5rem;
  }
  .card-meta {
    font-size: .75rem;
  }
  .resource-banner {
    margin-bottom: 3rem;
  }
  .resource-banner .button {
    flex-shrink: 1;
  }
  .book-heading-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .book-drawing {
    max-width: 600px;
  }
  .book-drawing svg {
    max-height: 290px;
    display: block;
    margin: auto;
  }
  .contents-list > div {
    grid-template-columns: 2rem 1fr;
    gap: 1rem;
  }
  .contents-list p {
    grid-column: 2;
  }
  .two-column {
    gap: 2rem;
  }
  .article-layout {
    grid-template-columns: 1fr;
    padding-top: 2rem;
  }
  .article-aside {
    position: static;
  }
  .article-aside nav {
    flex-direction: row;
    flex-wrap: wrap;
    border: 0;
  }
  .article-aside nav a {
    padding: .4rem .8rem .4rem 0;
    text-decoration: underline;
  }
  .article-aside > .text-link {
    display: none;
  }
  .article-heading {
    padding-bottom: 2rem;
  }
  .demo-grid {
    grid-template-columns: 1.05fr 1fr;
  }
  .resource-card {
    flex-wrap: wrap;
  }
  .resource-main {
    flex-basis: calc(100% - 90px);
  }
  .resource-action {
    margin-left: 80px;
    flex-direction: row;
    align-items: center;
    flex-wrap: wrap;
  }
  .resource-action p {
    text-align: left;
  }
  .resource-filter select {
    min-width: 0;
    width: 100%;
    order: 2;
  }
  .resource-filter p {
    margin-left: auto;
  }
  .footer-top {
    align-items: flex-start;
    flex-wrap: wrap;
    gap: 1.5rem;
  }
  .footer-bottom {
    gap: 1rem;
  }
  .faq-section {
    padding-block: 1rem 3rem;
  }
  .reading-note {
    margin-bottom: 3rem;
  }
}
@media (max-width: 540px) {
  body {
    font-size: 1rem;
  }
  .wrap {
    padding-inline: 1.25rem;
  }
  .draft-bar {
    font-size: .75rem;
  }
  .draft-extra {
    display: none;
  }
  .site-header {
    padding-inline: 1.25rem;
    gap: 1rem;
  }
  .wordmark {
    font-size: 1.05rem;
    gap: .5rem;
  }
  .wordmark svg {
    width: 30px;
  }
  .wordmark small {
    font-size: .75rem;
  }
  .hero-copy {
    padding: 2.5rem 1.25rem 2rem;
  }
  .hero h1 {
    font-size: 3.3rem;
  }
  .hero h1 > br:first-child {
    display: none;
  }
  .hero-copy > p {
    font-size: 1.05rem;
    max-width: 20rem;
  }
  .hero .actions {
    gap: .75rem;
    width: 100%;
  }
  .hero .button {
    padding: .75rem 1rem;
    font-size: .875rem;
    gap: .8rem;
  }
  .hero-object {
    margin: 0 1rem 1rem;
  }
  .object-heading {
    padding: 1rem;
  }
  .model-stage {
    height: 300px;
    min-height: 300px;
  }
  .model-toolbar {
    padding: .8rem .8rem .4rem;
    gap: .4rem;
    justify-content: center;
  }
  .segmented button {
    padding: .5rem .6rem;
    font-size: .875rem;
  }
  .motion-tools {
    width: 100%;
    justify-content: center;
  }
  .model-status,
  .model-disclaimer {
    margin-inline: 1rem;
  }
  .hero-footnote {
    font-size: .75rem;
  }
  .section-intro {
    display: block;
    margin-bottom: 2rem;
  }
  .section-intro > p {
    margin-top: 1.4rem;
    max-width: none;
  }
  .method-grid {
    grid-template-columns: 1fr;
    gap: 1.8rem;
  }
  .method-grid > div {
    position: relative;
    padding-left: 3rem;
  }
  .method-number {
    position: absolute;
    left: 0;
    top: .3rem;
  }
  .method-grid p {
    max-width: none;
  }
  .book-band {
    padding-block: 2.5rem;
  }
  .book-band-inner {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .book-tile {
    max-width: none;
  }
  .book-tile h2 {
    margin: 2rem 0 1rem;
    font-size: 2.7rem;
  }
  .tile-line {
    margin: 2rem 0 1rem;
  }
  .section-heading {
    align-items: flex-start;
    flex-direction: column;
    gap: 1rem;
  }
  .guide-card {
    display: block;
  }
  .guide-visual {
    height: 145px;
    min-height: 145px;
  }
  .card-content {
    padding: 1.4rem;
  }
  .resource-banner {
    display: block;
    padding-block: 2rem;
  }
  .resource-banner .button {
    margin-top: 1.5rem;
  }
  .page-heading h1 {
    font-size: 2.9rem;
  }
  .page-heading {
    padding-bottom: 2rem;
  }
  .breadcrumb {
    padding-top: 1.5rem;
    margin-bottom: 2rem;
    line-height: 1.5;
  }
  .lead {
    font-size: 1.15rem;
  }
  .book-heading-grid {
    gap: 2rem;
  }
  .book-heading-grid .actions {
    gap: .7rem;
  }
  .book-heading-grid .button {
    width: 100%;
  }
  .two-column {
    grid-template-columns: 1fr;
    gap: 2rem;
  }
  .section-space {
    padding-block: 1.5rem 3rem;
  }
  .plain-panel {
    padding: 1.5rem;
  }
  .reading-note {
    padding-block: 1.7rem;
  }
  .reading-note h2 {
    font-size: 1.75rem;
  }
  .reading-note .button {
    font-size: .875rem;
  }
  .article-heading h1 {
    font-size: 2.8rem;
  }
  .article-layout {
    padding-bottom: 3rem;
    gap: 2rem;
  }
  .reading-content h2 {
    font-size: 1.65rem;
  }
  .demo-grid {
    grid-template-columns: 1fr;
    padding: 1rem;
  }
  .plot svg {
    max-height: 325px;
  }
  .demo-top {
    padding: .85rem 1rem;
    font-size: .875rem;
  }
  .demo-grid .button {
    font-size: .9375rem;
  }
  .demo-result {
    padding: 1rem;
  }
  .resource-card {
    gap: 1rem;
    padding: 1.5rem 0;
  }
  .file-icon {
    width: 45px;
    min-height: 60px;
    font-size: .75rem;
  }
  .resource-main {
    flex-basis: calc(100% - 70px);
  }
  .resource-main h2 {
    font-size: 1.3rem;
  }
  .resource-action {
    margin-left: 61px;
    gap: .6rem;
    min-width: 0;
  }
  .resource-action .status-label {
    font-size: .75rem;
  }
  .file-meta {
    display: block;
  }
  .file-meta > div {
    display: block;
    margin-top: .5rem;
  }
  .file-meta dd {
    overflow-wrap: anywhere;
  }
  .compact {
    padding-inline: 1.25rem;
  }
  .faq-section summary {
    font-size: 1rem;
  }
  .contact-placeholder {
    gap: .5rem;
    flex-direction: column;
  }
  footer {
    padding: 2rem 1.25rem 1.25rem;
  }
  .footer-top {
    display: block;
  }
  .footer-top > p {
    margin: 1.5rem 0;
  }
  .footer-bottom {
    flex-direction: column;
    align-items: flex-start;
    padding-top: 1.5rem;
    margin-top: 1.5rem;
  }
  .reading-content p {
    line-height: 1.8;
  }
  .source-notes a {
    overflow-wrap: anywhere;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *:before,
  *:after {
    animation: none !important;
    transition: none !important;
  }
  .button:hover {
    transform: none;
  }
}
@media print {
  .draft-bar,
  .site-header,
  .article-aside,
  footer,
  .model-toolbar,
  .actions {
    display: none;
  }
  .wrap {
    padding: 0;
  }
  .article-layout {
    display: block;
  }
  .reading-content {
    max-width: none;
  }
  body {
    background: white;
    color: black;
  }
  .concept-demo {
    break-inside: avoid;
  }
}
@media (max-width: 540px) {
  .search-row {
    flex-direction: column;
    align-items: stretch;
  }
  .search-box {
    width: 100%;
  }
  .filter-box {
    min-width: 0;
  }
}
h1,
h2,
h3,
p {
  overflow-wrap: break-word;
}
.hero-copy,
.book-heading-grid > div,
.book-band-inner > * {
  min-width: 0;
}
.segmented {
  max-width: 100%;
  flex-wrap: wrap;
}
.file-icon {
  overflow-wrap: anywhere;
  text-align: center;
  padding: .2rem;
}
@media (max-width: 540px) {
  .site-header {
    height: auto;
    min-height: 82px;
    padding-block: .75rem;
    flex-wrap: wrap;
    gap: .5rem;
  }
  .wordmark {
    white-space: normal;
    max-width: 100%;
  }
  .wordmark > span {
    min-width: 0;
  }
  .menu-toggle {
    margin-left: auto;
  }
  .hero {
    grid-template-columns: minmax(0, 1fr);
  }
  .hero-copy h1,
  .book-tile h2 {
    overflow-wrap: anywhere;
  }
  .book-band-inner,
  .book-heading-grid,
  .two-column,
  .guide-grid {
    grid-template-columns: minmax(0, 1fr);
  }
  .contents-list > div {
    grid-template-columns: 2rem minmax(0, 1fr);
  }
  .segmented {
    justify-content: center;
  }
  .resource-action {
    margin-left: 0;
    max-width: 100%;
  }
  .resource-action .button {
    max-width: 100%;
    gap: .6rem;
    padding: .75rem;
  }
  .keycap {
    padding: .35rem .65rem;
  }
  .guide-visual {
    gap: .5rem;
  }
  .file-icon {
    font-size: .75rem;
  }
  .hero .actions .button {
    max-width: 100%;
  }
  .book-tile {
    padding: 1.3rem;
  }
  .resource-card .file-meta {
    overflow-wrap: anywhere;
  }
}