:root {
  --ink:#19252f;
  --navy:#142a3c;
  --blue:#2174b4;
  --muted:#697a88;
  --line:#e1e8ee;
  --surface:#f1f7fb;
  --header-height:88px;
  --sidebar-width:250px;
  --radius:16px;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 112px;
}
body {
  margin: 0;
  color: var(--ink);
  background: #fff;
  font:
    17px/1.85 -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    "PingFang SC",
    "Microsoft YaHei",
    sans-serif;
  -webkit-font-smoothing: antialiased;
}
a {
  color: var(--blue);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}
button,
input,
select,
textarea {
  font: inherit;
}
button {
  cursor: pointer;
}
button,
a,
input,
select,
textarea {
  outline-offset: 5px;
}
button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid #328ece;
}
::selection {
  background: #cce6fa;
  color: #142a3c;
}
header {
  height: var(--header-height);
  position: fixed;
  inset: 0 0 auto;
  z-index: 30;
  display: flex;
  align-items: center;
  gap: 26px;
  padding: 0 36px;
  background: rgb(250 253 255 / .92);
  border-bottom: 1px solid rgb(210 222 232 / .65);
  backdrop-filter: blur(18px);
}
.university-mark {
  display: flex;
  align-items: center;
  flex-shrink: 0;
  padding-right: 26px;
  border-right: 1px solid #d3e0e9;
}
.neu-logo {
  display: block;
  width: 143px;
  height: auto;
}
.brand {
  color: var(--navy);
  font-size: 22px;
  font-weight: 650;
  line-height: 1.4;
  letter-spacing: -.5px;
}
.brand:hover {
  text-decoration: none;
}
.brand-sub {
  display: block;
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 1px;
  margin-top: 5px;
  color: #677d8d;
}
header nav {
  display: flex;
  align-items: center;
  gap: 30px;
  margin-left: auto;
  white-space: nowrap;
  font-size: 15px;
}
header nav a {
  position: relative;
  color: #536573;
  padding: 8px 0;
}
header nav a:hover {
  color: var(--navy);
  text-decoration: none;
}
header nav a[aria-current=page] {
  color: var(--navy);
  font-weight: 600;
}
header nav a[aria-current=page]:after {
  content: "";
  position: absolute;
  width: 18px;
  height: 3px;
  border-radius: 2px;
  background: #4794cb;
  bottom: 0;
  left: calc(50% - 9px);
}
.menu {
  display: none;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 10px;
  width: 38px;
  height: 38px;
  padding: 0;
  font-size: 19px;
  color: var(--navy);
  line-height: 1;
  flex-shrink: 0;
}
.skip {
  position: fixed;
  top: -100px;
  left: 12px;
  z-index: 100;
  padding: 12px;
  background: white;
}
.skip:focus {
  top: 6px;
}
.sidebar {
  position: fixed;
  top: var(--header-height);
  bottom: 0;
  left: 0;
  width: var(--sidebar-width);
  padding: 28px 14px;
  overflow: auto;
  overscroll-behavior: contain;
  background: #f7fafc;
  border-right: 1px solid var(--line);
  z-index: 20;
  scrollbar-width: thin;
  scrollbar-color: #d4dfe7 transparent;
}
.side-title {
  padding: 0 12px 17px;
  font-size: 13px;
  letter-spacing: 1px;
  font-weight: 650;
  color: #294255;
}
.sidebar a {
  display: block;
  margin: 3px 0;
  padding: 9px 11px;
  color: #5c6e7c;
  border-radius: 7px;
  font-size: 13px;
  line-height: 1.75;
}
.sidebar a:hover {
  background: #eaf2f7;
  color: #244e6b;
  text-decoration: none;
}
.sidebar a.active {
  color: #195d8e;
  background: #e3f0fa;
  font-weight: 600;
}
.side-label {
  margin: 27px 12px 10px;
  font-size: 11px;
  color: #7f909b;
  letter-spacing: .3px;
}
.side-bottom {
  margin: 30px 12px 0;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  font-size: 11px;
  color: #788b99;
  line-height: 1.8;
}
.nav-num {
  display: inline-block;
  width: 25px;
  font-size: 11px;
  font-variant-numeric: tabular-nums;
  color: #8aa1b1;
}
main {
  margin: var(--header-height) 205px 0 var(--sidebar-width);
  padding: 43px 54px 70px;
  min-height: calc(100vh - var(--header-height));
  max-width: 1200px;
}
.breadcrumb {
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 26px;
}
.breadcrumb a {
  color: #647f92;
}
.chapter-kicker {
  font-size: 12px;
  letter-spacing: 2px;
  color: #5688ab;
  margin-bottom: 12px;
}
h1,
h2,
h3,
h4 {
  color: var(--navy);
}
h1 {
  font-size: 38px;
  line-height: 1.4;
  letter-spacing: -1px;
  font-weight: 650;
  margin: 0 0 24px;
}
h2 {
  font-size: 27px;
  font-weight: 600;
  line-height: 1.5;
  margin: 46px 0 24px;
  padding-bottom: 13px;
  border-bottom: 1px solid var(--line);
}
h3 {
  font-size: 22px;
  line-height: 1.6;
  font-weight: 600;
  margin: 30px 0 17px;
}
h4 {
  font-size: 19px;
}
.lead {
  font-size: 19px;
  color: var(--muted);
  margin: 0 0 25px;
}
.toc {
  position: fixed;
  right: 25px;
  top: 137px;
  width: 157px;
  border-left: 1px solid var(--line);
  padding-left: 20px;
  font-size: 12px;
  max-height: calc(100vh - 180px);
  overflow: auto;
}
.toc > div {
  font-weight: 600;
  color: #4e697d;
  margin-bottom: 16px;
}
.toc a {
  display: block;
  line-height: 1.75;
  color: #788b99;
  margin: 14px 0;
}
.toc a:hover {
  color: var(--blue);
}
.toc .subtoc {
  padding-left: 10px;
}
.toc-download {
  border-top: 1px solid var(--line);
  padding-top: 7px;
  margin-top: 26px;
  font-weight: 400 !important;
}
.page-footer {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid var(--line);
  padding-top: 26px;
  margin-top: 64px;
  color: #7b8c99;
  font-size: 12px;
}
.page-footer a {
  color: #7b8c99;
}
.home-view {
  background: #f5f8fb;
}
.home-view:before {
  content: "";
  position: absolute;
  inset: 88px 0 auto;
  height: 720px;
  background:
    radial-gradient(
      ellipse at 29% 38%,
      #dceefa9c,
      transparent 55%);
  pointer-events: none;
}
.home-view main {
  position: relative;
  width: 100%;
  max-width: 1392px;
  margin: var(--header-height) auto 0;
  padding: 0 64px 38px;
}
.home-view .sidebar {
  display: none;
  box-shadow: 12px 15px 45px #213c571a;
}
.home-view .sidebar.open {
  display: block;
}
.home-view .toc {
  display: none;
}
.home-view .menu {
  display: block;
  order: 5;
  margin-left: 0;
}
.course-hero {
  display: grid;
  grid-template-columns: 1.25fr 1fr;
  gap: 80px;
  align-items: center;
  padding: 70px 0 67px;
}
.hero-label {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 12px;
  letter-spacing: 1.8px;
  color: #637c8e;
  margin: 0 0 29px;
}
.hero-label:before {
  content: "";
  width: 6px;
  height: 6px;
  background: #548fb6;
  border-radius: 50%;
  box-shadow: 0 0 0 4px #dbeaf6;
}
.hero-copy h1 {
  font-size: clamp(42px, 4.5vw, 66px);
  line-height: 1.32;
  letter-spacing: -2px;
  font-weight: 600;
  margin: 0;
  color: #152b3c;
}
.hero-copy h1 span {
  color: #3f779e;
}
.hero-actions {
  display: flex;
  align-items: center;
  gap: 30px;
  margin-top: 37px;
}
.hero-actions .primary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 43px;
  padding: 13px 21px;
  background: #193950;
  border-color: #193950;
  font-size: 15px;
  border-radius: 9px;
}
.hero-actions .primary:hover {
  background: #254f6b;
  border-color: #254f6b;
  transform: translateY(-2px);
}
.hero-download {
  font-size: 14px;
  color: #637e91;
}
.hero-download span {
  margin-left: 15px;
}
.experiment-entry {
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-height: 378px;
  overflow: hidden;
  border: 1px solid #243f57;
  border-radius: 23px;
  padding: 25px 29px 28px;
  background:
    radial-gradient(
      ellipse at 63% 35%,
      #1b3f5b 0,
      #102636 49%,
      #0e1d2a 100%);
  color: #edf6ff;
  box-shadow: 0 22px 45px -24px #18395399;
  transition: transform .25s, box-shadow .25s;
}
.experiment-entry:hover {
  text-decoration: none;
  transform: translateY(-4px);
  box-shadow: 0 30px 55px -24px #183953aa;
}
.experiment-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 12px;
  letter-spacing: 1.4px;
  color: #b0c4d5;
  position: relative;
  z-index: 2;
}
.entry-arrow {
  display: grid;
  place-items: center;
  width: 29px;
  height: 29px;
  border: 1px solid #607b8d66;
  border-radius: 50%;
  font-size: 16px;
  color: #b7ccdb;
}
.experiment-art {
  height: 204px;
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
}
.orb-ring {
  position: absolute;
  top: 11px;
  width: 194px;
  height: 194px;
  border: 1px solid #a6d7ff44;
  border-radius: 50%;
  background:
    radial-gradient(
      circle at 50% 0,
      #a1d6ff0d,
      transparent 66%);
  box-shadow: inset 0 0 24px #99d6ff0b, 0 0 38px #7fbffb0f;
  transform: rotate(-25deg);
}
.orb-ring:before {
  content: "";
  position: absolute;
  inset: 14px -40px;
  border: 1px solid #8dc9f257;
  border-radius: 50%;
  transform: rotate(-25deg) scaleY(.42);
  box-shadow: 0 -3px 14px #82c6ff14;
}
.orb-ring:after {
  content: "";
  position: absolute;
  top: 28px;
  left: 26px;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #d3eeff;
  box-shadow: 0 0 14px 5px #80c4ff60;
}
.code-mark {
  font:
    47px/1.2 ui-monospace,
    SFMono-Regular,
    Consolas,
    monospace;
  letter-spacing: -5px;
  color: #c6e8ff;
  text-shadow: 0 0 32px #97d7ff77;
  position: relative;
  margin-top: 18px;
}
.code-caption {
  position: relative;
  font:
    10px/1.5 ui-monospace,
    SFMono-Regular,
    Consolas,
    monospace;
  letter-spacing: 2px;
  color: #7d9eb7;
  margin-top: 13px;
}
.experiment-bottom {
  position: relative;
  z-index: 1;
}
.experiment-bottom strong {
  font-size: 24px;
  letter-spacing: .5px;
  font-weight: 500;
}
.experiment-bottom p {
  font-size: 12px;
  color: #91aec3;
  margin: 7px 0 0;
  letter-spacing: .3px;
}
.section-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 23px;
}
.section-heading h2 {
  font-size: 23px;
  letter-spacing: -.4px;
  font-weight: 600;
  margin: 0;
  padding: 0;
  border: 0;
}
.section-heading > a {
  font-size: 12px;
  color: #6a8091;
}
.section-heading > a span {
  margin-left: 8px;
}
#course-groups {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}
.course-group {
  padding: 27px 25px 16px;
  border-radius: var(--radius);
  background: #ffffffde;
  border: 1px solid #e8eef3;
  transition: border-color .2s, box-shadow .2s;
}
.course-group:hover {
  border-color: #c8dce9;
  box-shadow: 0 10px 25px #244b6806;
}
.group-heading {
  display: flex;
  align-items: center;
  gap: 13px;
  margin-bottom: 21px;
}
.group-number {
  display: grid;
  place-items: center;
  width: 33px;
  height: 33px;
  background: #edf5fa;
  color: #698ea7;
  border: 1px solid #e0edf5;
  border-radius: 9px;
  font:
    12px/1 ui-monospace,
    SFMono-Regular,
    monospace;
}
.group-heading h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 0;
  letter-spacing: -.4px;
}
.chapter-list {
  margin: 15px 0 30px;
}
.chapter-list > a,
.resource-list > a {
  display: flex;
  align-items: center;
  gap: 14px;
  color: #304f65;
  padding: 18px 8px;
  border-bottom: 1px solid var(--line);
  font-size: 16px;
  line-height: 1.8;
}
.chapter-list > a:hover,
.resource-list > a:hover {
  background: #f1f7fb;
  text-decoration: none;
}
.chapter-number {
  min-width: 23px;
  color: #91a5b3;
  font:
    12px/1.7 ui-monospace,
    SFMono-Regular,
    monospace;
}
.row-arrow {
  margin-left: auto;
  color: #9db1bf;
  transition: transform .2s;
}
.course-group .chapter-list {
  margin: 0;
}
.course-group .chapter-list > a {
  font-size: 13px;
  line-height: 1.65;
  padding: 15px 0;
  gap: 9px;
  border-color: #edf1f5;
  min-height: 53px;
}
.course-group .chapter-list > a:last-child {
  border: 0;
}
.course-group .chapter-list > a:hover {
  background: transparent;
  color: #1c78b7;
}
.course-group .chapter-list > a:hover .row-arrow {
  transform: translateX(3px);
}
.course-group .chapter-number {
  font-size: 10px;
  min-width: 19px;
}
.course-group .row-arrow {
  font-size: 14px;
}
.study-guide {
  margin-top: 68px;
  padding-top: 35px;
  border-top: 1px solid #dce6ee;
}
.study-guide .section-heading {
  margin-bottom: 28px;
}
.reading-steps {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  list-style: none;
  padding: 0;
  margin: 0;
  gap: 37px;
}
.reading-steps li {
  display: flex;
  align-items: flex-start;
  gap: 14px;
}
.step-number {
  font:
    11px/2.2 ui-monospace,
    SFMono-Regular,
    monospace;
  color: #85a2b8;
}
.reading-steps strong {
  font-size: 15px;
  color: #304d62;
  font-weight: 550;
}
.reading-steps p {
  font-size: 13px;
  line-height: 1.95;
  color: #7b8c98;
  margin: 9px 0 0;
}
.home-links {
  display: flex;
  gap: 30px;
  font-size: 12px;
  margin-top: 29px;
}
.home-links a {
  color: #5e7b90;
}
.home-view .page-footer {
  margin-top: 45px;
  padding-top: 24px;
}
.article-actions {
  display: flex;
  align-items: center;
  gap: 22px;
  border-bottom: 1px solid var(--line);
  padding: 0 0 17px;
  margin: 19px 0 34px;
  font-size: 13px;
}
.article-actions .print-page {
  margin-left: auto;
}
.text-button {
  background: none;
  border: 0;
  color: var(--blue);
  font-size: 13px;
  padding: 5px 8px;
  white-space: nowrap;
  border-radius: 5px;
}
.text-button:hover {
  background: #eaf3fa;
}
.text-button:disabled {
  color: #9aa9b6;
  cursor: default;
}
.compact {
  font-size: 13px;
}
.prose {
  font-size: 18px;
  line-height: 1.95;
  color: #24323c;
}
.prose p {
  margin: 23px 0;
}
.prose h2 {
  margin-top: 54px;
  font-size: 28px;
}
.prose h3 {
  margin-top: 33px;
  font-size: 23px;
}
.prose li {
  margin: 10px 0;
}
.prose a {
  overflow-wrap: anywhere;
}
.prose img {
  display: block;
  max-width: 100%;
  height: auto;
  margin: 20px auto;
}
.prose figure {
  margin: 35px 0;
  padding: 18px 0;
}
.prose figcaption {
  font-size: 14px;
  color: #738693;
  text-align: center;
}
.prose :target {
  scroll-margin-top: 115px;
}
.prose :target.csl-entry {
  background: #edf7fe;
  outline: 8px solid #edf7fe;
}
.statement {
  background: #f0f8fd;
  border-left: 3px solid #8dc5e8;
  padding: 26px 30px;
  margin: 30px 0;
  border-radius: 0 10px 10px 0;
}
.statement.remark,
.statement.modernbox {
  background: #f5f9fc;
  border-color: #bfd8e8;
}
.statement.exercise {
  background: #eff7fd;
  border-color: #75b3db;
}
.statement-title {
  display: inline;
  color: #287cab;
  font-weight: 650;
  margin-right: .45em;
}
.statement-title + p {
  display: inline;
  margin: 0;
}
.statement p:last-child {
  margin-bottom: 0;
}
.statement-title:empty {
  display: none;
}
.statement .statement-title + ul,
.statement .statement-title + ol {
  margin-top: 15px;
}
.statement .math.display {
  padding: 17px 0;
}
.prose blockquote {
  margin: 28px 0;
  background: #f4f9fd;
  border-left: 3px solid #aacfe6;
  padding: 4px 27px;
}
.math.display {
  display: block;
  max-width: 100%;
  overflow-x: auto;
  padding: 14px 0;
}
.math .katex {
  font-size: 1.12em;
}
.katex-display {
  margin: .85em 0;
}
.table-scroll {
  max-width: 100%;
  overflow: auto;
  margin: 23px 0;
}
table {
  width: 100% !important;
  border-collapse: collapse;
  font-size: 15px;
  line-height: 1.8;
}
caption {
  caption-side: top;
  text-align: left;
  color: #637d8f;
  font-size: 14px;
  padding-bottom: 12px;
}
th {
  background: #edf5fb;
  color: #375b75;
  font-weight: 600;
}
td,
th {
  border-bottom: 1px solid #e0e9f0;
  padding: 13px 15px;
  text-align: left;
  vertical-align: top;
}
td {
  overflow-wrap: anywhere;
}
tr:last-child td {
  border-bottom-color: #cfdee8;
}
pre {
  font:
    13px/1.85 ui-monospace,
    SFMono-Regular,
    Consolas,
    "Liberation Mono",
    monospace;
  overflow: auto;
  background: #f5f8fb;
  border: 1px solid #e0e9f0;
  border-radius: 9px;
  padding: 22px;
  color: #31576f;
  tab-size: 4;
}
code {
  font-family:
    ui-monospace,
    SFMono-Regular,
    Consolas,
    monospace;
  font-size: .86em;
  background: #edf4f9;
  color: #37617e;
  padding: 2px 5px;
  border-radius: 4px;
  overflow-wrap: anywhere;
}
pre code {
  padding: 0;
  background: none;
  font-size: inherit;
}
.code-tools {
  display: flex;
  justify-content: flex-end;
  gap: 15px;
  align-items: center;
  font-size: 12px;
  margin: 22px 0 -12px;
}
.csl-entry {
  font-size: 16px;
  line-height: 1.9;
  overflow-wrap: anywhere;
  margin: 25px 0;
  padding: 0 0 22px 12px;
  border-bottom: 1px solid var(--line);
}
.ref-number {
  font-weight: 600;
  color: var(--blue);
  margin-right: 6px;
}
.chapter-labs > a {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  padding: 22px;
  background: #f0f7fc;
  border: 1px solid #e0edf6;
  border-radius: 10px;
  margin: 12px 0;
}
.chapter-labs > a:hover {
  background: #e9f4fb;
  text-decoration: none;
}
.chapter-labs > a > span {
  color: #6099bf;
}
.chapter-labs > a > span:last-child {
  margin-left: auto;
}
.chapter-labs strong {
  font-weight: 550;
}
.chapter-labs p {
  font-size: 14px;
  line-height: 1.8;
  margin: 6px 0 0;
  color: #6b879a;
}
.chapter-pagination {
  display: flex;
  justify-content: space-between;
  gap: 35px;
  border-top: 1px solid var(--line);
  margin-top: 48px;
  padding-top: 25px;
  font-size: 14px;
}
.chapter-pagination a {
  max-width: 48%;
}
.chapter-pagination a:last-child {
  text-align: right;
}
.chapter-pagination small {
  display: block;
  color: #91a2af;
  font-size: 11px;
  margin-bottom: 7px;
}
.source-note {
  display: none;
}
.reading-links {
  display: grid;
  gap: 14px;
  margin: 26px 0;
}
.reading-links a {
  padding: 18px 23px;
  background: #f1f8fc;
  border-left: 3px solid #a1cee8;
  border-radius: 0 9px 9px 0;
}
.reading-links small {
  display: block;
  font-size: 14px;
  color: #738c9c;
}
.prose .sourceCode .kw {
  color: #795c9e;
}
.prose .sourceCode .st {
  color: #488176;
}
.prose .sourceCode .co {
  color: #8b9ca6;
}
.prose .sourceCode .dv,
.prose .sourceCode .fl {
  color: #a4704b;
}
.primary,
.secondary {
  display: inline-block;
  padding: 10px 19px;
  border: 1px solid #246d9f;
  border-radius: 8px;
  font-size: 14px;
  line-height: 1.6;
  transition: background .2s, transform .2s;
}
.primary {
  background: #246d9f;
  color: white;
}
.primary:hover {
  background: #1b5d8b;
  text-decoration: none;
}
.primary:disabled {
  opacity: .5;
  cursor: wait;
}
.secondary {
  background: #fff;
  border-color: #d6e2ea;
  color: #496a82;
}
.secondary:hover {
  background: #edf5fb;
  text-decoration: none;
}
.secondary:disabled {
  color: #a2b0bb;
  border-color: #e2e9ef;
  cursor: default;
}
.download-row {
  display: flex;
  flex-wrap: wrap;
  gap: 13px;
  margin: 30px 0;
}
.dataset-list {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 2px 18px;
}
.dataset-list > div {
  display: flex;
  align-items: center;
  gap: 15px;
  border-bottom: 1px solid var(--line);
  padding: 13px 0;
  font-size: 13px;
}
.dataset-list > div:last-child {
  border: 0;
}
.dataset-list span {
  color: #8b9daa;
  margin-left: auto;
  white-space: nowrap;
}
.dataset-list a {
  white-space: nowrap;
}
.dataset-preview {
  color: #38698a;
  border: 0;
  background: none;
  font:
    13px ui-monospace,
    SFMono-Regular,
    monospace;
  text-align: left;
  padding: 5px 0;
  overflow-wrap: anywhere;
}
.dataset-preview:hover {
  color: #137bba;
}
.program-list > a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  border-bottom: 1px solid var(--line);
  padding: 13px 0;
}
.program-list code {
  background: none;
  font-size: 13px;
}
.tag {
  color: #417795;
  background: #eaf4fb;
  font-size: 11px;
  padding: 3px 9px;
  border-radius: 5px;
  white-space: nowrap;
}
.tag.muted {
  color: #8596a2;
  background: #f1f4f6;
}
.empty-note {
  font-size: 13px;
  color: #748d9e;
}
.index-filter {
  display: flex;
  align-items: center;
  gap: 20px;
  background: #f4f8fb;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 19px 22px;
  font-size: 14px;
}
.index-filter input {
  min-width: 0;
  flex: 1;
  background: white;
  border: 1px solid #d2e0eb;
  padding: 10px 14px;
  border-radius: 7px;
}
.index-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0 35px;
  margin-top: 26px;
}
.index-grid > a {
  padding: 15px 0;
  border-bottom: 1px solid var(--line);
}
.index-grid small {
  display: block;
  color: #90a2af;
  font-size: 12px;
}
.lab-view {
  background: #f8fafc;
}
.lab-view main {
  max-width: none;
  margin-right: 0;
  padding-inline: 38px;
}
.lab-view .toc {
  display: none;
}
.lab-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
}
.lab-heading h1 {
  font-size: 34px;
  margin-bottom: 8px;
}
.small-link {
  font-size: 13px;
}
.lab-intro {
  font-size: 15px;
  color: #6a8293;
  margin: 8px 0;
}
.lab-selector {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-top: 27px;
  padding-top: 15px;
}
.lab-selector label {
  font-size: 14px;
  white-space: nowrap;
}
.lab-selector select {
  flex: 1;
  max-width: 650px;
  min-width: 0;
  background: white;
  border: 1px solid #d1dfe9;
  border-radius: 8px;
  padding: 12px 14px;
  color: #355c78;
  font-size: 14px;
}
.experiment-description {
  font-size: 14px;
  color: #7e919e;
  margin: 12px 0 26px;
}
.parameters {
  display: flex;
  gap: 30px;
  padding: 20px 23px;
  border: 1px solid #dbe9f3;
  border-radius: 12px;
  background: #ecf5fb;
  margin: 20px 0;
}
.parameters label {
  display: block;
  flex: 1;
  max-width: 330px;
  font-size: 13px;
  color: #56758a;
}
.parameters output {
  float: right;
  color: #2878ab;
  font-variant-numeric: tabular-nums;
}
.parameters input[type=range] {
  display: block;
  width: 100%;
  accent-color: #3b8cbd;
  margin: 12px 0 3px;
}
.parameters input[type=checkbox] {
  accent-color: #3b8cbd;
  margin-right: 10px;
}
.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr);
  gap: 20px;
  align-items: start;
}
.code-pane,
.output-pane {
  min-width: 0;
  overflow: hidden;
  border: 1px solid #d9e5ef;
  border-radius: 13px;
  background: #fff;
}
.pane-heading {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  min-height: 50px;
  padding: 12px 17px;
  border-bottom: 1px solid #e6edf2;
  background: #f4f8fb;
  font-size: 13px;
  color: #607f95;
}
.code-pane {
  background: #132a3b;
  border-color: #1b364a;
}
.code-pane .pane-heading {
  background: #1b3448;
  color: #a3c1d7;
  border-color: #355268;
}
.code-pane .pane-heading .text-button {
  color: #b6d6ed;
}
.code-pane .text-button:hover {
  background: #294a64;
}
#code-editor {
  display: block;
  width: 100%;
  height: 420px;
  resize: vertical;
  padding: 23px 19px;
  background: #142a3b;
  border: 0;
  font:
    13px/1.9 ui-monospace,
    SFMono-Regular,
    Consolas,
    "Liberation Mono",
    monospace;
  color: #c5ddef;
  caret-color: #b6e4ff;
  white-space: pre;
  overflow: auto;
  tab-size: 4;
  outline-offset: -3px;
  color-scheme: dark;
}
#code-editor::selection {
  background: #2a5778;
  color: white;
}
.run-toolbar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 16px;
  border-top: 1px solid #30495d;
  background: #193245;
}
.run-toolbar .primary {
  background: #b9def9;
  border-color: #b9def9;
  color: #12344b;
  font-weight: 550;
}
.run-toolbar .primary:hover {
  background: #d6eeff;
}
.run-toolbar .secondary {
  background: transparent;
  border-color: #4b6578;
  color: #adcadc;
}
.run-toolbar .secondary:hover {
  background: #284a63;
}
.keyboard-hint {
  margin-left: auto;
  font-size: 10px;
  color: #839fb2;
  white-space: nowrap;
}
.runtime-help {
  border-top: 1px solid #30495d;
  padding: 13px 17px;
  font-size: 12px;
  color: #9db8ca;
  line-height: 1.8;
}
.runtime-help summary {
  cursor: pointer;
}
.runtime-help p {
  margin: 14px 0;
}
.runtime-help code {
  background: #244257;
  color: #bdd6e7;
}
.run-status {
  min-height: 46px;
  padding: 14px 18px;
  border-bottom: 1px solid #edf2f6;
  color: #6e8a9d;
  font-size: 13px;
  line-height: 1.6;
}
.run-status.error {
  color: #ac594d;
  background: #fff7f4;
}
#result-output {
  padding: 0 18px 18px;
  min-height: 440px;
  max-height: 1000px;
  overflow: auto;
}
.waiting-result {
  text-align: center;
  padding: 100px 15px;
  color: #8ba2b3;
}
.result-symbol {
  font-size: 37px;
  color: #b9cddc;
}
.waiting-result h3 {
  font-size: 17px;
  font-weight: 400;
  color: #62869e;
  margin: 10px 0;
}
.waiting-result p {
  font-size: 13px;
  margin: 0;
}
.result-block {
  margin: 18px 0 30px;
  padding-bottom: 15px;
  border-bottom: 1px solid var(--line);
}
.result-block h3 {
  font-size: 16px;
  color: #446c87;
  font-weight: 500;
  margin: 12px 0;
}
.chart-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 9px;
  margin: 12px 0 7px;
}
.chart-controls label {
  display: flex;
  align-items: center;
  gap: 5px;
  min-width: 0;
  font-size: 11px;
  color: #849dad;
}
.chart-controls select {
  max-width: 120px;
  padding: 4px;
  border: 1px solid #d6e3ec;
  border-radius: 5px;
  background: white;
  color: #4e718b;
  font-size: 12px;
}
.result-chart svg {
  display: block;
  width: 100%;
  height: auto;
}
.result-block table {
  font-size: 12px;
  white-space: nowrap;
}
.result-block .table-scroll {
  max-height: 340px;
  margin: 12px 0;
}
.result-block td,
.result-block th {
  padding: 8px 10px;
}
.error-output {
  white-space: pre-wrap;
  background: #fff6f3;
  color: #a4473f;
  border-color: #f2d9d2;
  font-size: 12px;
}
#run-log {
  font-size: 12px;
  white-space: pre-wrap;
  max-height: 500px;
}
.html-result {
  width: 100%;
  height: 650px;
  border: 0;
  background: white;
}
.lab-footnote {
  font-size: 12px;
  color: #849caa;
  margin: 22px 0;
}
@media (min-width: 1800px) {
  body:not(.home-view):not(.lab-view) main {
    width: 1160px;
    margin-inline: auto;
  }
}
@media (max-width: 1390px) {
  .toc {
    display: none;
  }
  main {
    margin-right: 0;
    padding-inline: 54px;
  }
  .home-view main {
    padding-inline: 48px;
  }
  .course-hero {
    gap: 55px;
  }
  .course-group {
    padding-inline: 21px;
  }
  .group-heading {
    gap: 10px;
  }
  .group-heading h3 {
    font-size: 16px;
  }
  header {
    gap: 22px;
    padding-inline: 28px;
  }
  .neu-logo {
    width: 132px;
  }
  .university-mark {
    padding-right: 22px;
  }
}
@media (max-width: 1100px) {
  .workspace {
    grid-template-columns: 1fr;
  }
  #result-output {
    max-height: none;
    min-height: 260px;
  }
  .waiting-result {
    padding: 50px 10px;
  }
  .brand {
    font-size: 20px;
  }
  header nav {
    gap: 21px;
    font-size: 14px;
  }
  .home-view main {
    padding-inline: 36px;
  }
  .course-hero {
    gap: 35px;
    padding-top: 53px;
  }
  .hero-copy h1 {
    font-size: 48px;
  }
  .experiment-entry {
    min-height: 356px;
    padding: 21px 25px;
  }
  .experiment-art {
    height: 195px;
  }
  #course-groups {
    gap: 14px;
  }
  .course-group {
    padding: 23px 16px 13px;
  }
  .group-heading {
    display: block;
    margin-bottom: 14px;
  }
  .group-heading h3 {
    margin-top: 13px;
  }
  .course-group .chapter-list > a {
    font-size: 12px;
  }
  .hero-actions {
    gap: 20px;
  }
  .hero-actions .primary {
    gap: 25px;
  }
}
@media (max-width: 980px) {
  :root {
    --header-height:78px;
  }
  html {
    scroll-padding-top: 100px;
  }
  header {
    padding-inline: 24px;
    gap: 19px;
  }
  .neu-logo {
    width: 119px;
  }
  .university-mark {
    padding-right: 19px;
  }
  .brand {
    font-size: 18px;
  }
  .brand-sub {
    font-size: 9px;
    letter-spacing: .5px;
  }
  header nav {
    gap: 17px;
    font-size: 13px;
  }
  .menu {
    display: block;
    order: 5;
  }
  .sidebar {
    display: none;
    width: min(85vw, 310px);
    box-shadow: 12px 15px 45px #213c571a;
  }
  .sidebar.open {
    display: block;
  }
  main {
    margin: var(--header-height) auto 0;
    width: 100%;
    max-width: 900px;
    padding: 38px 38px 60px;
  }
  .lab-view main {
    margin-left: 0;
  }
  .home-view main {
    max-width: 980px;
  }
  .home-view:before {
    top: 78px;
  }
  .hero-copy h1 {
    font-size: 43px;
    letter-spacing: -1.5px;
  }
  .course-hero {
    gap: 28px;
  }
  .hero-actions .primary {
    font-size: 14px;
    padding: 11px 17px;
    gap: 22px;
  }
  .hero-actions {
    gap: 20px;
  }
  .hero-download {
    font-size: 12px;
  }
  .hero-download span {
    margin-left: 6px;
  }
  .experiment-entry {
    min-height: 340px;
  }
  .experiment-bottom strong {
    font-size: 21px;
  }
  .experiment-bottom p {
    font-size: 11px;
  }
  .experiment-art {
    height: 182px;
  }
  .orb-ring {
    width: 175px;
    height: 175px;
  }
  .reading-steps {
    gap: 24px;
  }
  .reading-steps li {
    gap: 10px;
  }
}
@media (max-width: 760px) {
  header {
    gap: 15px;
    padding-inline: 20px;
  }
  .neu-logo {
    width: 116px;
  }
  .university-mark {
    padding-right: 16px;
  }
  .brand {
    font-size: 18px;
    flex: 1;
  }
  header nav {
    display: none;
  }
  .menu {
    margin-left: auto;
  }
  .home-view main {
    padding: 0 24px 30px;
  }
  .course-hero {
    grid-template-columns: 1fr;
    gap: 37px;
    padding: 46px 0 43px;
  }
  .hero-copy h1 {
    font-size: 52px;
    line-height: 1.3;
    letter-spacing: -1.8px;
  }
  .hero-label {
    margin-bottom: 21px;
    font-size: 11px;
  }
  .hero-actions {
    margin-top: 27px;
    gap: 27px;
  }
  .hero-actions .primary {
    padding: 12px 18px;
    gap: 36px;
  }
  .hero-download {
    font-size: 13px;
  }
  .experiment-entry {
    min-height: 250px;
    padding: 22px 24px;
    justify-content: space-between;
  }
  .experiment-art {
    position: absolute;
    right: 17px;
    top: 16px;
    width: 195px;
    height: 220px;
    opacity: .8;
  }
  .experiment-top {
    justify-content: space-between;
  }
  .experiment-top > span:first-child {
    font-size: 11px;
  }
  .experiment-bottom {
    margin-top: 114px;
    max-width: 260px;
  }
  .experiment-bottom strong {
    font-size: 23px;
  }
  .experiment-bottom p {
    font-size: 11px;
  }
  .section-heading {
    gap: 12px;
    margin-bottom: 18px;
  }
  .section-heading h2 {
    font-size: 21px;
  }
  .section-heading > a {
    font-size: 11px;
  }
  .section-heading > a span {
    margin-left: 2px;
  }
  #course-groups {
    grid-template-columns: 1fr;
    gap: 15px;
  }
  .course-group {
    padding: 22px 23px 13px;
  }
  .group-heading {
    display: flex;
    gap: 12px;
    margin-bottom: 10px;
  }
  .group-heading h3 {
    font-size: 17px;
    margin: 0;
  }
  .course-group .chapter-list > a {
    font-size: 14px;
    min-height: 53px;
    padding-block: 14px;
    gap: 13px;
  }
  .course-group .chapter-number {
    font-size: 11px;
  }
  .study-guide {
    margin-top: 40px;
    padding-top: 29px;
  }
  .reading-steps {
    grid-template-columns: 1fr;
    gap: 24px;
  }
  .reading-steps li {
    gap: 17px;
  }
  .reading-steps strong {
    font-size: 15px;
  }
  .reading-steps p {
    font-size: 13px;
    margin-top: 5px;
  }
  .home-links {
    gap: 24px;
    flex-wrap: wrap;
  }
  .home-view .page-footer {
    margin-top: 35px;
  }
  .page-footer {
    display: block;
    margin-top: 44px;
  }
  .page-footer a {
    display: inline-block;
    margin-top: 8px;
  }
  main,
  .lab-view main {
    padding: 29px 23px 50px;
  }
  .breadcrumb {
    font-size: 12px;
    margin-bottom: 22px;
  }
  h1 {
    font-size: 30px;
  }
  h2 {
    font-size: 25px;
  }
  .lead {
    font-size: 17px;
  }
  .prose {
    font-size: 17px;
    line-height: 1.95;
  }
  .prose h2 {
    font-size: 25px;
  }
  .prose h3 {
    font-size: 21px;
  }
  .prose ul,
  .prose ol {
    padding-left: 24px;
  }
  .statement {
    padding: 21px 21px;
    margin: 26px 0;
  }
  .prose table {
    min-width: 520px;
  }
  .prose figure {
    padding: 8px 0;
  }
  .article-actions {
    gap: 13px;
    flex-wrap: wrap;
  }
  .chapter-pagination {
    gap: 15px;
  }
  .chapter-labs > a {
    gap: 13px;
    padding: 18px;
  }
  .csl-entry {
    font-size: 15px;
  }
  .index-grid {
    grid-template-columns: 1fr;
  }
  .index-filter {
    display: block;
    padding: 17px;
  }
  .index-filter input {
    display: block;
    width: 100%;
    margin-top: 9px;
  }
  .dataset-list {
    padding-inline: 12px;
  }
  .dataset-list > div {
    gap: 10px;
    font-size: 12px;
  }
  .dataset-preview,
  .program-list code {
    font-size: 12px;
  }
  .download-row .primary,
  .download-row .secondary {
    font-size: 13px;
  }
  .lab-heading {
    display: block;
  }
  .lab-heading h1 {
    font-size: 30px;
  }
  .lab-heading .small-link {
    display: inline-block;
    margin-bottom: 8px;
  }
  .lab-intro {
    font-size: 14px;
  }
  .lab-selector {
    display: block;
    margin-top: 21px;
    padding-top: 10px;
  }
  .lab-selector label {
    display: block;
    margin-bottom: 8px;
  }
  .lab-selector select {
    width: 100%;
    max-width: none;
    font-size: 13px;
  }
  .experiment-description {
    font-size: 13px;
  }
  .parameters {
    gap: 20px;
    flex-wrap: wrap;
    padding: 18px;
  }
  .parameters label {
    min-width: 150px;
    max-width: none;
  }
  .keyboard-hint {
    display: none;
  }
  #code-editor {
    height: 355px;
    font-size: 12px;
    padding: 18px 15px;
  }
  .run-toolbar {
    gap: 10px;
    padding: 13px;
  }
  .run-toolbar .primary,
  .run-toolbar .secondary {
    padding: 9px 13px;
    font-size: 12px;
  }
  .pane-heading {
    font-size: 12px;
  }
  .runtime-help {
    font-size: 12px;
  }
  .run-status {
    font-size: 12px;
  }
  .result-block .table-scroll {
    margin-inline: 0;
  }
}
@media (max-width: 420px) {
  header {
    gap: 12px;
    padding-inline: 16px;
  }
  .university-mark {
    padding-right: 12px;
  }
  .neu-logo {
    width: 94px;
  }
  .brand {
    font-size: 16px;
  }
  .brand-sub {
    font-size: 8px;
    letter-spacing: .2px;
  }
  .menu {
    width: 32px;
    height: 34px;
    font-size: 17px;
  }
  .home-view main {
    padding-inline: 22px;
  }
  .hero-copy h1 {
    font-size: 45px;
  }
  .hero-actions {
    gap: 24px;
  }
  .experiment-art {
    right: 0;
    width: 170px;
    opacity: .7;
  }
  .orb-ring {
    width: 160px;
    height: 160px;
    top: 12px;
  }
  .code-mark {
    font-size: 39px;
    margin-top: -2px;
  }
  .experiment-bottom strong {
    font-size: 22px;
  }
  .experiment-entry {
    padding: 20px;
  }
  .experiment-top .entry-arrow {
    width: 27px;
    height: 27px;
  }
  .course-group {
    padding-inline: 20px;
  }
  .section-heading > a {
    font-size: 10px;
  }
  .home-links {
    gap: 21px;
  }
  .program-list code {
    overflow-wrap: anywhere;
    word-break: break-word;
  }
  .article-actions {
    font-size: 12px;
  }
  .text-button {
    font-size: 12px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  * {
    transition: none !important;
  }
}
@media print {
  header,
  .sidebar,
  .toc,
  .menu,
  .article-actions,
  .page-footer,
  .lab-panel {
    display: none !important;
  }
  main,
  .lab-view main,
  .home-view main {
    margin: 0;
    padding: 0;
    max-width: none;
    width: auto;
  }
  body,
  .home-view {
    background: white;
    color: black;
  }
  .home-view:before {
    display: none;
  }
  h2 {
    break-after: avoid;
  }
  .statement {
    break-inside: avoid;
    background: #fff !important;
    border-left-color: #b1c7d4 !important;
  }
  .experiment-entry {
    box-shadow: none;
  }
  .course-group {
    break-inside: avoid;
  }
}