/* Introduction — the book's educational premise, moved from the inside cover. */
.introduction-view {
  --intro-navy: #123d78;
  --intro-deep: #0d2d5d;
  --intro-cyan: #19b9c5;
  --intro-amber: #f1b84a;
  --intro-orange: #e77b4b;
  --intro-ink: #24313a;
  --intro-muted: #65747c;
}

.introduction-page {
  min-height: 1300px;
  padding: clamp(58px, 8vw, 92px) clamp(42px, 9vw, 108px) 108px;
  font-family: var(--reading);
}

.introduction-header {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(250px, .7fr);
  align-items: end;
  padding-bottom: 38px;
  border-bottom: 2px solid var(--intro-navy);
}

.introduction-header > p,
.introduction-continuation-head > p {
  grid-column: 1 / -1;
  margin: 0 0 16px;
  color: var(--intro-cyan);
  font: 750 .72rem/1 var(--sans);
  letter-spacing: .16em;
  text-transform: uppercase;
}

.introduction-header h1 {
  max-width: 780px;
  margin: 0;
  color: var(--intro-navy);
  font: 780 clamp(3.9rem, 7.7vw, 7.2rem)/.82 var(--sans);
  letter-spacing: -.06em;
  text-transform: uppercase;
  text-wrap: balance;
}

.introduction-header h1 em {
  color: var(--intro-orange);
  font-family: var(--serif);
  font-weight: 400;
  letter-spacing: -.035em;
  text-transform: none;
}

.introduction-header > blockquote {
  margin: 0 0 5px;
  padding-left: 27px;
  border-left: 4px solid var(--intro-amber);
  color: var(--intro-muted);
  font: italic 400 1.2rem/1.55 var(--serif);
}

.introduction-lead-grid {
  display: grid;
  grid-template-columns: minmax(0, .95fr) minmax(390px, 1.05fr);
  gap: clamp(45px, 6vw, 76px);
  align-items: center;
  margin-top: 68px;
}

.introduction-prose {
  color: var(--intro-ink);
  font-size: clamp(1.12rem, calc(1.02rem + .25vw), 1.26rem);
  line-height: 1.72;
  letter-spacing: .006em;
}

.introduction-prose-wide {
  max-width: 800px;
  margin: 48px auto 0;
}

.introduction-prose p { margin: 0 0 1.18em; }
.introduction-prose strong { color: var(--intro-navy); }

.introduction-central {
  margin: 28px 0;
  padding: 27px 0 27px 29px;
  border-left: 5px solid var(--intro-amber);
  color: var(--intro-navy);
  font: italic 700 clamp(1.5rem, 2.4vw, 2.05rem)/1.34 var(--serif);
}

.intro-conditions .thinking-field { height: 460px; }
.intro-conditions figcaption { font-size: .92rem; }

.introduction-question-shift {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 24px;
  align-items: stretch;
  margin-top: 70px;
  padding: 32px;
  background: #e5f0ef;
}

.introduction-question-shift article {
  padding: 22px 26px;
  background: #fbfaf6;
}

.introduction-question-shift span {
  color: var(--intro-orange);
  font: 750 .7rem/1 var(--sans);
  letter-spacing: .14em;
  text-transform: uppercase;
}

.introduction-question-shift p {
  margin: 12px 0 0;
  color: var(--intro-navy);
  font: 700 clamp(1.25rem, 2vw, 1.7rem)/1.3 var(--reading);
}

.introduction-question-shift i {
  align-self: center;
  color: var(--intro-orange);
  font: 400 2.2rem/1 var(--serif);
  font-style: normal;
}

.introduction-continuation-head {
  display: grid;
  grid-template-columns: 1fr .7fr;
  align-items: end;
  padding-bottom: 40px;
  border-bottom: 2px solid var(--intro-navy);
}

.introduction-continuation-head h2 {
  margin: 0;
  color: var(--intro-navy);
  font: 780 clamp(3.8rem, 7vw, 6.5rem)/.82 var(--sans);
  letter-spacing: -.055em;
  text-transform: uppercase;
  text-wrap: balance;
}

.introduction-continuation-head h2 em {
  color: var(--intro-orange);
  font-family: var(--serif);
  font-weight: 400;
  text-transform: none;
}

.introduction-continuation-head blockquote {
  margin: 0;
  padding-left: 28px;
  border-left: 4px solid var(--intro-amber);
  color: var(--intro-muted);
  font: italic 400 1.22rem/1.55 var(--serif);
}

.introduction-actions {
  display: grid;
  grid-template-columns: 245px 1fr;
  gap: 34px;
  align-items: start;
  margin-top: 64px;
  padding: 28px 0;
  border-block: 1px solid #b9c7c9;
}

.introduction-actions p {
  margin: 0;
  color: #526068;
  font-size: 1.06rem;
  line-height: 1.56;
}

.introduction-actions ol {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 23px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.introduction-actions li {
  display: flex;
  align-items: baseline;
  gap: 7px;
  color: var(--intro-navy);
  font: 730 clamp(.98rem, 1.2vw, 1.1rem)/1.3 var(--sans);
}

.introduction-actions li span {
  color: var(--intro-orange);
  font-size: .62rem;
}

.introduction-principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  margin-top: 35px;
  border-top: 5px solid var(--intro-cyan);
  background: #b9cbcc;
}

.introduction-principles article {
  padding: 31px;
  background: #f7f8f4;
}

.introduction-principles span {
  color: var(--intro-orange);
  font: 750 .66rem/1 var(--sans);
  letter-spacing: .12em;
}

.introduction-principles h3 {
  min-height: 2.2em;
  margin: 14px 0 11px;
  color: var(--intro-navy);
  font: 750 clamp(1.25rem, 2vw, 1.7rem)/1.08 var(--sans);
  letter-spacing: -.025em;
}

.introduction-principles p,
.introduction-parts p,
.introduction-start p {
  margin: 0;
  color: #48575f;
  font-size: 1.04rem;
  line-height: 1.6;
}

.introduction-parts {
  margin-top: 58px;
  padding: 40px;
  background: var(--intro-deep);
  color: white;
}

.introduction-parts header span,
.introduction-start header span {
  color: var(--intro-amber);
  font: 750 .68rem/1 var(--sans);
  letter-spacing: .14em;
  text-transform: uppercase;
}

.introduction-parts header h3,
.introduction-start header h3 {
  margin: 12px 0 30px;
  color: white;
  font: 750 clamp(1.7rem, 3vw, 2.45rem)/1.08 var(--sans);
  letter-spacing: -.03em;
}

.introduction-parts > div {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 34px;
}

.introduction-parts article {
  padding-top: 18px;
  border-top: 1px solid #50729a;
}

.introduction-parts b {
  display: block;
  margin-bottom: 9px;
  color: var(--intro-cyan);
  font: 750 .78rem/1 var(--sans);
  letter-spacing: .12em;
  text-transform: uppercase;
}

.introduction-parts p { color: #d5e1eb; }

.introduction-toolkit {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr) auto;
  gap: clamp(24px, 4vw, 48px);
  align-items: center;
  margin-top: 22px;
  padding: 30px 34px;
  border: 1px solid #abc8ca;
  border-left: 7px solid var(--intro-cyan);
  background: linear-gradient(110deg, #edf7f5 0%, #fbfaf6 68%);
  color: var(--intro-ink);
  break-inside: avoid;
}

.introduction-toolkit-label {
  align-self: stretch;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding-right: 26px;
  border-right: 1px solid #b9cccd;
}

.introduction-toolkit-label span {
  color: var(--intro-orange);
  font: 750 .7rem/1.2 var(--sans);
  letter-spacing: .14em;
  text-transform: uppercase;
}

.introduction-toolkit-label b {
  color: var(--intro-navy);
  font: 780 clamp(3.5rem, 6vw, 5.3rem)/.78 var(--sans);
  letter-spacing: -.06em;
}

.introduction-toolkit-copy h3 {
  margin: 0 0 12px;
  color: var(--intro-navy);
  font-family: var(--sans);
}

.introduction-toolkit-copy h3 strong,
.introduction-toolkit-copy h3 em {
  display: block;
}

.introduction-toolkit-copy h3 strong {
  font-size: clamp(1.42rem, 2.5vw, 2rem);
  line-height: 1.08;
  letter-spacing: -.025em;
}

.introduction-toolkit-copy h3 em {
  margin-top: 6px;
  color: var(--intro-orange);
  font: 700 clamp(1.05rem, 1.7vw, 1.32rem)/1.2 var(--sans);
  font-style: normal;
}

.introduction-toolkit-copy p {
  max-width: 690px;
  margin: 0;
  color: #48575f;
  font-size: 1.04rem;
  line-height: 1.58;
}

.introduction-toolkit > button {
  min-width: 190px;
  padding: 15px 18px;
  border: 1px solid var(--intro-navy);
  background: var(--intro-navy);
  color: white;
  font: 750 .78rem/1.2 var(--sans);
  letter-spacing: .04em;
  text-align: left;
  cursor: pointer;
}

.introduction-toolkit > button span {
  float: right;
  color: var(--intro-amber);
  font-size: 1rem;
}

.introduction-toolkit > button:hover,
.introduction-toolkit > button:focus-visible {
  background: var(--intro-cyan);
  color: var(--intro-deep);
}

.introduction-book-map {
  width: min(920px, 100%);
  margin: 64px auto 0;
  padding: 0;
  break-inside: avoid;
}

.introduction-book-map img {
  display: block;
  width: 100%;
  height: auto;
  border: 1px solid #d8dedb;
  background: #fbfaf6;
  box-shadow: 0 22px 55px rgba(13, 45, 93, .12);
}

.introduction-book-map figcaption {
  max-width: 760px;
  margin: 20px auto 0;
  color: var(--intro-muted);
  font-size: 1rem;
  line-height: 1.55;
  text-align: center;
}

.introduction-book-map figcaption b { color: var(--intro-navy); }

.introduction-start {
  max-width: 900px;
  margin: 58px auto 0;
  padding: 42px clamp(30px, 5vw, 55px);
  border: 1px solid #b8c8ca;
  background: #fbfaf6;
}

.introduction-start header h3 {
  margin-bottom: 25px;
  color: var(--intro-navy);
}

.introduction-start-note {
  max-width: 650px;
  margin: -8px 0 28px !important;
  color: var(--intro-muted) !important;
}

.introduction-start ol {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 25px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.introduction-start li {
  padding-top: 16px;
  border-top: 3px solid var(--intro-cyan);
}

.introduction-start li > span {
  display: block;
  margin-bottom: 9px;
  color: var(--intro-orange);
  font: 750 .66rem/1 var(--sans);
  letter-spacing: .12em;
}

.introduction-start blockquote {
  margin: 35px 0 0;
  color: var(--intro-navy);
  font: italic 400 clamp(1.7rem, 3vw, 2.5rem)/1.25 var(--serif);
  text-align: center;
}

.theme-soft .introduction-page { background: #f6efe4; }
.theme-focus .introduction-page { background: #fff; }

@media (max-width: 960px) {
  .introduction-header,
  .introduction-continuation-head { grid-template-columns: 1fr; gap: 28px; }
  .introduction-lead-grid { grid-template-columns: 1fr; }
  .intro-conditions { width: min(580px, 100%); margin-inline: auto; }
  .introduction-principles { grid-template-columns: 1fr; }
  .introduction-principles h3 { min-height: 0; }
  .introduction-parts > div { grid-template-columns: 1fr; gap: 22px; }
  .introduction-toolkit { grid-template-columns: 120px minmax(0, 1fr); }
  .introduction-toolkit > button { grid-column: 2; justify-self: start; }
}

@media (max-width: 700px) {
  .introduction-page { min-height: 0; padding: 46px 22px 90px; }
  .introduction-header h1,
  .introduction-continuation-head h2 { font-size: clamp(3.2rem, 15vw, 4.6rem); line-height: .9; }
  .introduction-question-shift { grid-template-columns: 1fr; padding: 20px; }
  .introduction-question-shift i { justify-self: center; transform: rotate(90deg); }
  .introduction-actions { grid-template-columns: 1fr; gap: 20px; }
  .introduction-actions ol { display: grid; grid-template-columns: 1fr 1fr; }
  .introduction-parts { padding: 30px 23px; }
  .introduction-toolkit { grid-template-columns: 1fr; padding: 27px 23px; }
  .introduction-toolkit-label { flex-direction: row; align-items: end; padding: 0 0 18px; border-right: 0; border-bottom: 1px solid #b9cccd; }
  .introduction-toolkit-label b { font-size: 3.6rem; }
  .introduction-toolkit > button { grid-column: 1; width: 100%; }
  .introduction-book-map { margin-top: 42px; }
  .introduction-book-map figcaption { font-size: .95rem; text-align: left; }
  .introduction-start { padding: 32px 23px; }
  .introduction-start ol { grid-template-columns: 1fr; }
}

@media print {
  .introduction-page { break-after: page; }
  .introduction-question-shift,
  .introduction-principles,
  .introduction-parts,
  .introduction-toolkit,
  .introduction-start,
  .introduction-book-map,
  .intro-conditions { break-inside: avoid; }
}