.learn-page,
.learn-page h1,
.learn-page h2,
.learn-page h3,
.learn-page h4,
.learn-page .btn {
  letter-spacing: 0;
}

.learn-hero {
  padding: 76px 0 68px;
  border-bottom: 1px solid var(--border);
}

.learn-breadcrumbs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 34px;
  color: var(--faint);
  font: 12px/1.5 var(--font-mono);
}

.learn-breadcrumbs a:hover {
  color: var(--cyan);
}

.learn-hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 300px;
  gap: 68px;
  align-items: end;
}

.learn-hero h1 {
  max-width: 850px;
  margin-top: 22px;
  font-size: 64px;
  line-height: 1.02;
}

.learn-hero .lede {
  max-width: 760px;
  margin-top: 24px;
  color: var(--text-dim);
  font-size: 19px;
  line-height: 1.65;
}

.learn-source {
  border-top: 2px solid var(--cyan);
  padding-top: 18px;
}

.learn-source span {
  display: block;
  color: var(--cyan);
  font: 11px/1.4 var(--font-mono);
  text-transform: uppercase;
}

.learn-source strong {
  display: block;
  margin-top: 10px;
  font-size: 20px;
  line-height: 1.3;
}

.learn-source p {
  margin-top: 9px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.55;
}

.learn-section {
  padding: 76px 0;
}

.learn-section + .learn-section {
  border-top: 1px solid var(--border);
}

.learn-section-head {
  max-width: 760px;
}

.learn-section-head h2 {
  margin-top: 14px;
  font-size: 40px;
  line-height: 1.08;
}

.learn-section-head p {
  margin-top: 16px;
  color: var(--muted);
  line-height: 1.65;
}

.guide-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
  margin-top: 36px;
}

.guide-card {
  display: flex;
  min-height: 330px;
  flex-direction: column;
  border: 1px solid var(--border-strong);
  border-radius: 8px;
  background: var(--surface);
  padding: 25px;
}

.guide-card:nth-child(1) {
  border-top: 3px solid var(--cyan);
}

.guide-card:nth-child(2) {
  border-top: 3px solid var(--amber);
}

.guide-card:nth-child(3) {
  border-top: 3px solid var(--violet);
}

.guide-card .guide-number {
  color: var(--faint);
  font: 12px/1 var(--font-mono);
}

.guide-card h3 {
  margin-top: 28px;
  font-size: 25px;
  line-height: 1.18;
}

.guide-card p {
  margin-top: 14px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.62;
}

.guide-card a {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: auto;
  padding-top: 24px;
  color: var(--cyan);
  font: 600 12px/1.4 var(--font-mono);
}

.concept-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 42px;
  margin-top: 36px;
  border-top: 1px solid var(--border);
}

.concept-list > div {
  display: grid;
  grid-template-columns: 150px minmax(0, 1fr);
  gap: 20px;
  padding: 21px 0;
  border-bottom: 1px solid var(--border);
}

.concept-list dt {
  color: var(--text);
  font-weight: 700;
}

.concept-list dd {
  color: var(--muted);
  font-size: 14px;
  line-height: 1.55;
}

.learn-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 26px;
  margin-top: 38px;
}

.learn-principles article {
  padding-top: 18px;
  border-top: 2px solid var(--border-strong);
}

.learn-principles h3 {
  font-size: 19px;
}

.learn-principles p {
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.6;
}

.article-hero {
  padding: 66px 0 56px;
  border-bottom: 1px solid var(--border);
}

.article-hero h1 {
  max-width: 920px;
  margin-top: 18px;
  font-size: 58px;
  line-height: 1.04;
}

.article-dek {
  max-width: 780px;
  margin-top: 24px;
  color: var(--text-dim);
  font-size: 20px;
  line-height: 1.6;
}

.article-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 9px 22px;
  margin-top: 28px;
  color: var(--faint);
  font: 12px/1.5 var(--font-mono);
}

.article-shell {
  display: grid;
  grid-template-columns: 220px minmax(0, 760px);
  gap: 70px;
  justify-content: center;
  padding: 66px 0 90px;
}

.article-toc {
  position: sticky;
  top: calc(var(--nav-h) + 24px);
  align-self: start;
  border-top: 1px solid var(--border-strong);
  padding-top: 16px;
}

.article-toc strong {
  color: var(--faint);
  font: 11px/1.4 var(--font-mono);
  text-transform: uppercase;
}

.article-toc a {
  display: block;
  margin-top: 13px;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.4;
}

.article-toc a:hover {
  color: var(--cyan);
}

.article-body {
  min-width: 0;
}

.article-body > p:first-child {
  color: var(--text-dim);
  font-size: 20px;
  line-height: 1.72;
}

.article-body h2 {
  margin-top: 58px;
  padding-top: 12px;
  border-top: 1px solid var(--border);
  font-size: 34px;
  line-height: 1.15;
}

.article-body h3 {
  margin-top: 34px;
  font-size: 22px;
  line-height: 1.25;
}

.article-body p,
.article-body li {
  color: var(--text-dim);
  font-size: 16px;
  line-height: 1.76;
}

.article-body p {
  margin-top: 18px;
}

.article-body ul,
.article-body ol {
  display: grid;
  gap: 10px;
  margin: 20px 0 0;
  padding-left: 24px;
}

.article-body a {
  color: var(--cyan);
  text-decoration: underline;
  text-decoration-color: rgba(67, 231, 243, 0.4);
  text-underline-offset: 3px;
}

.article-body code {
  border: 1px solid var(--border);
  border-radius: 4px;
  background: var(--surface-muted);
  padding: 2px 6px;
  color: var(--text);
  font-size: 0.9em;
}

.article-callout {
  margin-top: 28px;
  border-left: 3px solid var(--amber);
  background: var(--surface);
  padding: 20px 22px;
}

.article-callout strong {
  display: block;
  color: var(--amber);
  font-size: 15px;
}

.article-callout p {
  margin-top: 7px;
  font-size: 14px;
}

.process-steps {
  display: grid;
  gap: 0;
  margin-top: 28px;
  border-top: 1px solid var(--border);
}

.process-step {
  display: grid;
  grid-template-columns: 52px minmax(0, 1fr);
  gap: 18px;
  padding: 22px 0;
  border-bottom: 1px solid var(--border);
}

.process-step > span {
  color: var(--cyan);
  font: 600 12px/1.5 var(--font-mono);
}

.process-step h3 {
  margin: 0;
  font-size: 19px;
}

.process-step p {
  margin-top: 7px;
  font-size: 14px;
}

.evidence-table {
  width: 100%;
  margin-top: 24px;
  border-collapse: collapse;
  font-size: 13px;
}

.evidence-table th,
.evidence-table td {
  border-bottom: 1px solid var(--border);
  padding: 13px 10px;
  text-align: left;
  vertical-align: top;
}

.evidence-table th {
  color: var(--faint);
  font: 600 11px/1.4 var(--font-mono);
  text-transform: uppercase;
}

.evidence-table td {
  color: var(--text-dim);
}

.checklist {
  margin-top: 28px;
  border-top: 1px solid var(--border);
}

.checklist li {
  position: relative;
  padding: 15px 0 15px 30px;
  border-bottom: 1px solid var(--border);
  list-style: none;
}

.checklist li::before {
  position: absolute;
  top: 20px;
  left: 3px;
  width: 9px;
  height: 9px;
  border: 1px solid var(--cyan);
  content: "";
}

.related-guides {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
  margin-top: 28px;
}

.related-guides a {
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 18px;
  text-decoration: none;
}

.related-guides strong {
  display: block;
  color: var(--text);
  font-size: 16px;
  line-height: 1.35;
}

.related-guides span {
  display: block;
  margin-top: 7px;
  color: var(--muted);
  font-size: 12px;
  line-height: 1.5;
}

@media (max-width: 980px) {
  .learn-hero-grid,
  .article-shell {
    grid-template-columns: 1fr;
  }

  .learn-source {
    max-width: 520px;
  }

  .guide-grid,
  .learn-principles {
    grid-template-columns: 1fr;
  }

  .guide-card {
    min-height: 0;
  }

  .article-toc {
    position: static;
  }
}

@media (max-width: 700px) {
  .learn-hero,
  .article-hero {
    padding: 40px 0 44px;
  }

  .learn-hero h1,
  .article-hero h1 {
    font-size: 42px;
  }

  .learn-hero .lede,
  .article-dek,
  .article-body > p:first-child {
    font-size: 17px;
  }

  .learn-section {
    padding: 54px 0;
  }

  .concept-list,
  .related-guides {
    grid-template-columns: 1fr;
  }

  .concept-list > div {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .article-shell {
    gap: 40px;
    padding: 44px 0 64px;
  }

  .article-body h2 {
    font-size: 28px;
  }

  .evidence-table {
    display: block;
    overflow-x: auto;
  }
}