:root {
  --ink: #26333f;
  --muted: #667482;
  --paper: #fafbfa;
  --white: #ffffff;
  --line: #cbd4da;
  --blue: #006fb9;
  --orange: #c6532d;
  --green: #4f8f73;
  --gold: #b4951d;
  --pale-blue: #e7f2f8;
  --pale-orange: #f8ece7;
  --pale-green: #eaf3ef;
  --pale-gold: #f7f2d9;
  --reading-width: 49rem;
  --reader-body-font: Georgia, "Times New Roman", serif;
  --reader-body-size: 18px;
  --reader-body-line: 1.72;
  --reader-section-space: 4.25rem;
}

html[data-reader-theme="contemporary"] {
  --reading-width: 52rem;
  --reader-body-font: -apple-system, BlinkMacSystemFont, "Segoe UI", Arial, sans-serif;
  --reader-body-size: 17px;
  --reader-body-line: 1.68;
  --reader-section-space: 3.8rem;
}

html[data-reader-theme="compact"] {
  --reading-width: 55rem;
  --reader-body-font: "Iowan Old Style", "Palatino Linotype", Palatino, Georgia, serif;
  --reader-body-size: 16px;
  --reader-body-line: 1.58;
  --reader-section-space: 3rem;
}

.course-wrap {
  margin: 0 auto;
  max-width: 74rem;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
}

.course-site-header {
  background: var(--white);
  border-bottom: 1px solid #d8dfe2;
  color: var(--ink);
  font-family: Arial, Helvetica, sans-serif;
}

.course-header-inner {
  align-items: center;
  display: flex;
  justify-content: space-between;
  min-height: 4.25rem;
}

.course-brand,
.course-site-header nav a {
  color: var(--ink);
  text-decoration: none;
}

.course-brand {
  color: #174b67;
  font-size: 1.05rem;
  font-weight: 800;
}

.course-site-header nav {
  display: flex;
  gap: 1.5rem;
}

.course-site-header nav a {
  color: #60717b;
  font-size: .86rem;
}

.course-site-header nav a[aria-current="page"] {
  color: #174b67;
  font-weight: 750;
}

.course-home {
  font-family: Arial, Helvetica, sans-serif;
}

.course-hero {
  background: #f4f6f3;
  border-bottom: 1px solid #d8dfe2;
  color: var(--ink);
  padding: clamp(4rem, 7vw, 6rem) 0;
}

.course-hero-layout {
  align-items: center;
  display: grid;
  gap: clamp(3rem, 7vw, 6rem);
  grid-template-columns: minmax(0, 1.35fr) minmax(16rem, .65fr);
}

.course-breadcrumb,
.course-eyebrow {
  font-size: .72rem;
  font-weight: 800;
  letter-spacing: .04em;
  text-transform: uppercase;
}

.course-breadcrumb {
  color: #60717b;
  margin: 0 0 2rem;
}

.course-eyebrow {
  color: var(--orange);
  margin: 0 0 .65rem;
}

.course-hero .course-eyebrow {
  color: var(--orange);
}

.course-hero h1 {
  font-family: Georgia, "Times New Roman", serif;
  font-size: clamp(3.5rem, 7vw, 5.8rem);
  letter-spacing: -.045em;
  line-height: .96;
  margin: 0;
  max-width: 9ch;
}

.course-lead {
  color: #52636c;
  font-size: clamp(1.1rem, 2vw, 1.35rem);
  line-height: 1.5;
  margin: 1.5rem 0 0;
  max-width: 38rem;
}

.course-actions {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  gap: .8rem 1.3rem;
  margin-top: 2.2rem;
}

.course-actions a {
  color: #174b67;
  font-size: .9rem;
  font-weight: 750;
}

.course-button {
  border: 1px solid #60717b;
  border-radius: 4px;
  color: var(--ink);
  display: inline-block;
  font-size: .88rem;
  font-weight: 800;
  padding: .72rem 1rem;
  text-decoration: none;
}

.course-button-primary {
  background: #174b67;
  border-color: #174b67;
  color: var(--white) !important;
}

.course-hero-mark {
  background: var(--white);
  border: 1px solid #d2dadd;
  border-top: 5px solid #174b67;
  box-shadow: 0 1rem 2.5rem rgb(38 51 63 / 8%);
  display: grid;
  padding: 1.8rem 2rem 2rem;
}

.course-hero-mark span {
  color: #174b67;
  font: 700 clamp(3.75rem, 7vw, 5rem)/.9 Georgia, "Times New Roman", serif;
}

.course-hero-mark strong {
  font-size: .95rem;
  margin-top: .75rem;
  text-transform: uppercase;
}

.course-hero-mark small {
  color: var(--muted);
  line-height: 1.45;
  margin-top: .25rem;
}

.course-hero-mark a {
  color: #174b67;
  font-size: .82rem;
  font-weight: 800;
  margin-top: 1.25rem;
}

.course-intro,
.course-files {
  background: var(--white);
  padding: 4rem 0;
}

.course-files {
  background: #e9f0f2;
}

.course-split,
.course-section-head {
  display: grid;
  gap: 3rem;
  grid-template-columns: minmax(0, 1fr) minmax(20rem, .85fr);
}

.course-home h2 {
  font: 700 clamp(2rem, 4vw, 3.15rem)/1.08 Georgia, "Times New Roman", serif;
  margin: 0;
}

.course-home h3 {
  color: #173b4c;
  font: 700 1.35rem/1.2 Georgia, "Times New Roman", serif;
  margin: .35rem 0 .7rem;
}

.course-split p,
.course-section-head > p,
.practice-list article > p:not(.course-eyebrow) {
  color: #52636c;
  font-size: 1rem;
  line-height: 1.65;
  margin-top: 0;
}

.course-chapters,
.course-practice {
  padding-bottom: 4.5rem;
  padding-top: 4.5rem;
}

.course-section-head {
  align-items: end;
  margin-bottom: 2.4rem;
}

.course-map {
  border-top: 2px solid #174b67;
  column-gap: 2.75rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  list-style: none;
  margin: 0;
  padding: 0;
}

.course-map li {
  border-bottom: 1px solid var(--line);
}

.course-map a,
.course-map li > div {
  align-items: baseline;
  color: var(--ink);
  display: grid;
  gap: 1rem;
  grid-template-columns: 2.25rem minmax(0, 1fr);
  padding: .95rem .25rem;
  text-decoration: none;
}

.course-map span {
  color: var(--orange);
  font-size: .72rem;
  font-weight: 800;
}

.course-map strong {
  font: 700 1.05rem/1.25 Georgia, "Times New Roman", serif;
}

.course-map small {
  color: var(--muted);
  font-size: .75rem;
  grid-column: 2;
  text-align: left;
}

.course-map a:hover strong {
  color: #174b67;
}

.course-map .is-forthcoming {
  opacity: .57;
}

.practice-list {
  background: var(--line);
  border: 1px solid var(--line);
  display: grid;
  gap: 1px;
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.practice-list article {
  background: var(--white);
  padding: 2rem;
}

.practice-list a {
  font-size: .88rem;
  font-weight: 800;
}

.course-footer {
  background: #202d37;
  color: #cbd6db;
  font: .78rem/1.5 Arial, Helvetica, sans-serif;
  padding: 1.5rem 0;
}

.directory-page {
  margin: 0 auto;
  max-width: 64rem;
  padding: 5rem 1.5rem;
}

.directory-header {
  border-bottom: 1px solid var(--line);
  margin-bottom: 2.5rem;
  padding-bottom: 2rem;
}

.directory-header h1 {
  font-size: clamp(2.8rem, 6vw, 5rem);
  line-height: 1;
  margin: 0;
}

.directory-header p:not(.course-eyebrow) {
  color: var(--muted);
  max-width: 42rem;
}

.directory-header > a {
  font-family: Arial, Helvetica, sans-serif;
  font-size: .85rem;
  font-weight: 750;
}

.directory-list {
  list-style: none;
  margin: 0;
  padding: 0;
}

.directory-list li {
  border-bottom: 1px solid var(--line);
  display: grid;
  gap: 1rem;
  grid-template-columns: 2.25rem minmax(0, 1fr);
  padding: .95rem 0;
}

.directory-list li > span {
  color: var(--orange);
  font: 800 .75rem/1.5 Arial, Helvetica, sans-serif;
}

.directory-list a,
.directory-list strong {
  color: var(--ink);
  font-weight: 700;
}

.directory-list small {
  color: var(--muted);
  display: block;
  font: .75rem/1.45 Arial, Helvetica, sans-serif;
  margin-top: .2rem;
}

.directory-list .is-forthcoming {
  opacity: .58;
}

.download-table {
  border-top: 1px solid var(--line);
  font-family: Arial, Helvetica, sans-serif;
}

.download-row {
  align-items: center;
  border-bottom: 1px solid var(--line);
  display: grid;
  gap: 1rem;
  grid-template-columns: minmax(0, 1fr) 10rem 11rem;
  padding: 1rem .25rem;
}

.download-heading {
  color: var(--muted);
  font-size: .7rem;
  font-weight: 800;
  text-transform: uppercase;
}

.download-row a {
  font-size: .82rem;
  font-weight: 750;
}

.download-pending {
  color: var(--muted);
  font-size: .8rem;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--reader-body-font);
  font-size: var(--reader-body-size);
  line-height: var(--reader-body-line);
  margin: 0;
}

a {
  color: #005b98;
  text-underline-offset: 0.18em;
}

.site-header {
  align-items: center;
  background: var(--ink);
  color: var(--white);
  display: flex;
  gap: 1.2rem;
  min-height: 4.5rem;
  padding: 1rem clamp(1.25rem, 4vw, 3.75rem);
}

.site-header p {
  color: #cfdae2;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.82rem;
  margin: 0;
}

.book-name {
  color: var(--white);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 1.05rem;
  font-weight: 750;
  text-decoration: none;
}

.preview-badge {
  border: 1px solid #788793;
  border-radius: 999px;
  color: #e6edf1;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.68rem;
  margin-left: auto;
  padding: 0.25rem 0.65rem;
  text-transform: uppercase;
}

.reader-style-switcher {
  border: 1px solid #788793;
  border-radius: 4px;
  display: grid;
  grid-template-columns: repeat(3, auto);
  margin-left: auto;
  overflow: hidden;
}

.reader-style-switcher button {
  background: transparent;
  border: 0;
  border-right: 1px solid #788793;
  color: #dfe8ed;
  cursor: pointer;
  font: 700 .69rem/1 Arial, Helvetica, sans-serif;
  min-height: 2rem;
  padding: .45rem .62rem;
}

.reader-style-switcher button:last-child {
  border-right: 0;
}

.reader-style-switcher button[aria-pressed="true"] {
  background: var(--orange);
  color: var(--white);
}

.reader-style-switcher + .preview-badge {
  margin-left: 0;
}

.reader-layout {
  display: grid;
  grid-template-columns: minmax(16rem, 21rem) minmax(0, 1fr);
}

.reader-sidebar {
  background: #f0f3f4;
  border-right: 1px solid var(--line);
}

.sidebar-inner {
  max-height: calc(100vh - 4.5rem);
  overflow-y: auto;
  padding: 3rem 2rem;
  position: sticky;
  top: 0;
}

.sidebar-kicker,
.sidebar-chapter,
.nav-heading,
.download-link,
.chapter-number,
.chapter-meta,
.semantic-label,
.chapter-footer,
.chapter-list,
.source-notes-list {
  font-family: Arial, Helvetica, sans-serif;
}

.sidebar-kicker {
  color: var(--orange);
  font-size: 0.72rem;
  font-weight: 750;
  margin: 0 0 0.2rem;
  text-transform: uppercase;
}

.sidebar-chapter {
  font-size: 1.05rem;
  font-weight: 700;
  margin: 0 0 2rem;
}

.nav-heading {
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 750;
  margin: 0 0 0.8rem;
  padding-bottom: 0.55rem;
  text-transform: uppercase;
}

.reader-sidebar ol {
  list-style: none;
  margin: 0;
  padding: 0;
}

.reader-sidebar li {
  line-height: 1.35;
}

.reader-sidebar li + li {
  margin-top: 0.7rem;
}

.reader-sidebar nav a {
  color: #455761;
  display: block;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.82rem;
  text-decoration: none;
}

.reader-sidebar nav a:hover,
.reader-sidebar nav a:focus-visible {
  color: var(--orange);
  text-decoration: underline;
}

.chapter-list {
  border-bottom: 1px solid var(--line);
  margin-bottom: 1.8rem;
  padding-bottom: 1.3rem;
}

.chapter-list a {
  align-items: baseline;
  display: grid !important;
  gap: 0.65rem;
  grid-template-columns: 1.15rem 1fr;
}

.chapter-list a span {
  color: var(--orange);
  font-size: 0.72rem;
  font-weight: 750;
}

.chapter-list a[aria-current="page"] {
  color: var(--ink);
  font-weight: 750;
}

.download-link {
  border-top: 1px solid var(--line);
  display: block;
  font-size: 0.8rem;
  font-weight: 750;
  margin-top: 2rem;
  padding-top: 1rem;
}

.download-link-secondary {
  border-top: 0;
  margin-top: .7rem;
  padding-top: 0;
}

main {
  min-width: 0;
}

.chapter-header {
  background:
    linear-gradient(112deg, var(--pale-blue), var(--pale-green));
  border-bottom: 1px solid #bfd0d6;
  padding: clamp(3.5rem, 7vw, 6.5rem)
    max(2rem, calc((100% - var(--reading-width)) / 2));
}

.chapter-number {
  color: var(--orange);
  font-size: 0.78rem;
  font-weight: 750;
  margin: 0 0 0.8rem;
  text-transform: uppercase;
}

.chapter-header h1 {
  font-size: clamp(2.65rem, 5vw, 4.6rem);
  line-height: 1.02;
  margin: 0;
  max-width: 13ch;
}

.chapter-deck {
  color: #36505d;
  font-size: 1.22rem;
  line-height: 1.5;
  margin: 1.5rem 0 0;
  max-width: 39rem;
}

.chapter-meta {
  color: var(--muted);
  display: flex;
  flex-wrap: wrap;
  font-size: 0.76rem;
  gap: 0.6rem 1.2rem;
  margin-top: 2rem;
}

.chapter-meta span + span::before {
  color: var(--gold);
  content: "|";
  margin-right: 1.2rem;
}

.chapter-body {
  margin: 0 auto;
  max-width: var(--reading-width);
  padding: 3.5rem 0 5rem;
}

.chapter-body h2,
.chapter-body h3 {
  scroll-margin-top: 1.5rem;
}

.chapter-body h2 {
  border-top: 1px solid var(--line);
  font-size: 1.9rem;
  line-height: 1.2;
  margin: var(--reader-section-space) 0 1.25rem;
  padding-top: 1.5rem;
}

.chapter-body h2:first-child {
  border-top: 0;
  margin-top: 0;
  padding-top: 0;
}

.chapter-body h3 {
  color: #304d5b;
  font-size: 1.28rem;
  line-height: 1.3;
  margin: 2.5rem 0 0.8rem;
}

.chapter-body p {
  margin: 0 0 1.2rem;
}

.chapter-body pre {
  max-width: 100%;
  overflow-x: auto;
  padding-bottom: .45rem;
}

html[data-reader-theme="compact"] .chapter-body p {
  margin-bottom: .92rem;
}

html[data-reader-theme="compact"] .semantic-block {
  margin-bottom: 1.55rem;
  margin-top: 1.55rem;
}

.chapter-body strong {
  color: #183a49;
}

.chapter-body li + li {
  margin-top: 0.42rem;
}

.semantic-block {
  border-left: 5px solid var(--green);
  margin: 2.2rem 0;
  padding: 1.2rem 1.4rem 0.3rem;
}

.semantic-block p:last-child {
  margin-bottom: 0.8rem;
}

.semantic-keypoint,
.semantic-casestudy {
  background: var(--pale-green);
}

.semantic-quickconcept {
  background: var(--pale-blue);
  border-color: var(--blue);
}

.semantic-warning {
  background: var(--pale-orange);
  border-color: var(--orange);
}

.semantic-sideline,
.semantic-historicalnote {
  background: var(--pale-gold);
  border-color: var(--gold);
}

.semantic-studyandlearn {
  background: #eef0f7;
  border-color: #6778a0;
}

.semantic-label {
  color: var(--muted);
  font-size: 0.68rem;
  font-weight: 750;
  margin-bottom: 0.5rem;
  text-transform: uppercase;
}

.semantic-label + p {
  margin-top: 0;
}

.table-scroll {
  margin: 2rem 0 2.4rem;
  overflow-x: auto;
}

table {
  border-collapse: collapse;
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.84rem;
  line-height: 1.45;
  min-width: 40rem;
  width: 100%;
}

th,
td {
  border-bottom: 1px solid var(--line);
  padding: 0.8rem 0.9rem;
  text-align: left;
  vertical-align: top;
}

th {
  background: var(--ink);
  color: var(--white);
  font-weight: 700;
}

tbody tr:nth-child(even) {
  background: #f0f4f5;
}

.anchored-table[id="tab:ch02-elasticity-family"] table {
  table-layout: fixed;
}

.anchored-table[id="tab:ch02-elasticity-family"] th:nth-child(1),
.anchored-table[id="tab:ch02-elasticity-family"] td:nth-child(1) {
  width: 18%;
}

.anchored-table[id="tab:ch02-elasticity-family"] th:nth-child(2),
.anchored-table[id="tab:ch02-elasticity-family"] td:nth-child(2) {
  width: 29%;
  white-space: nowrap;
}

.anchored-table[id="tab:ch02-elasticity-family"] th:nth-child(3),
.anchored-table[id="tab:ch02-elasticity-family"] td:nth-child(3) {
  width: 25%;
}

.anchored-table[id="tab:ch02-elasticity-family"] th:nth-child(4),
.anchored-table[id="tab:ch02-elasticity-family"] td:nth-child(4) {
  width: 28%;
}

.anchored-table[id="tab:ch02-elasticity-family"] td:not(:nth-child(2)) {
  overflow-wrap: anywhere;
}

@media (max-width: 640px) {
  .anchored-table[id="tab:ch02-elasticity-family"] table {
    min-width: 44rem;
  }
}

.chapter-figure {
  border-bottom: 1px solid var(--line);
  border-top: 1px solid var(--line);
  margin: 2.8rem 0 3.2rem;
  padding: 1.5rem 0 1.15rem;
}

.chapter-figure > p:first-child {
  margin: 0;
}

.chapter-figure img {
  display: block;
  height: auto;
  margin: 0 auto;
  max-height: 34rem;
  max-width: 100%;
  width: auto;
}

.chapter-figure > p:last-child {
  color: var(--muted);
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.82rem;
  line-height: 1.55;
  margin: 1rem 0 0;
}

.katex-display {
  margin: 1.7rem 0;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.15rem 0;
}

.source-notes-list {
  color: #465965;
  font-size: 0.82rem;
  line-height: 1.55;
}

.source-notes-list ol {
  padding-left: 1.5rem;
}

.source-notes-list li {
  margin-bottom: 1rem;
}

.footnote-ref {
  font-family: Arial, Helvetica, sans-serif;
  font-size: 0.72em;
  font-weight: 700;
}

.footnote-backref {
  margin-left: 0.25rem;
  text-decoration: none;
}

.chapter-footer {
  border-top: 1px solid var(--line);
  color: var(--muted);
  display: flex;
  font-size: 0.76rem;
  justify-content: space-between;
  margin: 0 auto;
  max-width: var(--reading-width);
  padding: 1.5rem 0 3rem;
}

.chapter-footer p {
  margin: 0;
}

@media (max-width: 980px) {
  .course-hero-layout,
  .course-split,
  .course-section-head {
    grid-template-columns: 1fr;
  }

  .course-hero-mark {
    max-width: 26rem;
  }

  .reader-layout {
    display: block;
  }

  .site-header {
    flex-wrap: wrap;
  }

  .reader-sidebar {
    border-bottom: 1px solid var(--line);
    border-right: 0;
  }

  .sidebar-inner {
    max-height: none;
    padding: 1.25rem max(1.25rem, calc((100% - var(--reading-width)) / 2));
    position: static;
  }

  .sidebar-kicker,
  .reader-sidebar nav {
    display: none;
  }

  .sidebar-chapter,
  .download-link {
    display: inline-block;
    margin: 0;
  }

  .download-link {
    border: 0;
    float: right;
    padding: 0;
  }

  .chapter-body,
  .chapter-footer {
    margin-left: 1.5rem;
    margin-right: 1.5rem;
  }
}

@media (max-width: 640px) {
  .course-header-inner {
    align-items: flex-start;
    flex-direction: column;
    gap: .3rem;
    justify-content: center;
    padding-bottom: .8rem;
    padding-top: .8rem;
  }

  .course-site-header nav {
    gap: 1rem;
  }

  .course-hero h1 {
    font-size: 3.7rem;
  }

  .course-map a,
  .course-map li > div {
    grid-template-columns: 2rem minmax(0, 1fr);
  }

  .course-map {
    grid-template-columns: 1fr;
  }

  .practice-list {
    grid-template-columns: 1fr;
  }

  .download-row {
    align-items: start;
    grid-template-columns: 1fr;
  }

  .download-heading {
    display: none;
  }

  body {
    font-size: 17px;
  }

  .site-header {
    align-items: flex-start;
    display: block;
  }

  .reader-style-switcher {
    margin: .8rem 0 0;
    width: 100%;
  }

  .reader-style-switcher button {
    min-height: 2.35rem;
  }

  .site-header p {
    margin-top: 0.15rem;
  }

  .preview-badge {
    display: inline-block;
    margin: 0.7rem 0 0;
  }

  .chapter-header {
    padding: 3rem 1.5rem;
  }

  .chapter-header h1 {
    font-size: 2.8rem;
  }

  .chapter-meta span + span::before {
    content: none;
    margin: 0;
  }

  .chapter-body h2 {
    font-size: 1.65rem;
  }

  .chapter-footer {
    display: block;
  }

  .chapter-footer p + p {
    margin-top: 0.35rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
}