/* ============================================================================
   Learn AI: the quiet, product-page look shared with Daily AI news
   One neutral grey ground, white tiles, system type, one blue for actions,
   generous space. Presentation only, and deliberately scoped: the History of
   AI chapter (#history-section) keeps its own dark design untouched, so no
   rule here reaches inside it.
   ========================================================================== */

.learn-ai-page {
  --minimal-ink: #1d1d1f;
  --minimal-muted: #6e6e73;
  --minimal-soft: #86868b;
  --minimal-accent: #0071e3;
  --minimal-accent-hover: #0077ed;
  --minimal-ground: #f5f5f7;
  --minimal-tile: #ffffff;
  --minimal-font: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Inter", "Helvetica Neue", Helvetica, Arial, sans-serif;

  background: var(--minimal-ground);
}

/* ---------- cover ---------- */
.learn-ai-page .learn-cover {
  max-width: 1080px;
  padding: clamp(64px, 9vw, 120px) 22px clamp(48px, 6vw, 80px);
  font-family: var(--minimal-font);
  text-align: center;
}

.learn-ai-page .learn-cover-copy {
  max-width: 820px;
  margin: 0 auto;
}

.learn-ai-page .learn-eyebrow {
  margin: 0 0 14px;
  color: var(--minimal-soft);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
  text-transform: none;
}

.learn-ai-page .learn-cover h1 {
  max-width: none;
  margin: 0;
  color: var(--minimal-ink);
  font-size: clamp(40px, 6.4vw, 72px);
  font-weight: 600;
  letter-spacing: -0.035em;
  line-height: 1.05;
}

.learn-ai-page .learn-cover-sub {
  max-width: none;
  margin: 22px auto 0;
  color: var(--minimal-muted);
  font-size: clamp(17px, 1.7vw, 21px);
  letter-spacing: -0.01em;
  line-height: 1.5;
}

/* ---------- chapter picker: three white tiles ---------- */
.learn-ai-page .learn-deck {
  gap: 20px;
  margin-top: clamp(44px, 6vw, 72px);
  text-align: left;
}

.learn-ai-page .learn-card {
  min-height: 0;
  padding: 30px 30px 32px;
  border: 0;
  border-radius: 18px;
  background: var(--minimal-tile);
  color: var(--minimal-ink);
  box-shadow: none;
  transition: box-shadow 0.3s ease, transform 0.3s ease;
}

.learn-ai-page .learn-card:hover,
.learn-ai-page .learn-card:focus-visible {
  border-color: transparent;
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.learn-ai-page .learn-card:focus-visible {
  outline: 2px solid var(--minimal-accent);
  outline-offset: 3px;
}

.learn-ai-page .learn-card-num {
  color: var(--minimal-soft);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0;
}

.learn-ai-page .learn-card-icon {
  width: 44px;
  height: 44px;
  margin-top: 28px;
  border: 0;
  border-radius: 12px;
  background: var(--minimal-ground);
  color: var(--minimal-ink);
  box-shadow: none;
}

.learn-ai-page .learn-card-icon svg {
  width: 26px;
  height: 26px;
  stroke-width: 1.8;
}

.learn-ai-page .learn-card-copy strong {
  color: var(--minimal-ink);
  font-size: clamp(21px, 2vw, 24px);
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
}

.learn-ai-page .learn-card-copy small {
  color: var(--minimal-muted);
  font-size: 15px;
  line-height: 1.4;
}

.learn-ai-page .learn-card-arrow {
  top: 26px;
  right: 26px;
  background: transparent;
  color: var(--minimal-accent);
  font-size: 17px;
  font-weight: 400;
}

.learn-ai-page .learn-card:hover .learn-card-arrow,
.learn-ai-page .learn-card:focus-visible .learn-card-arrow {
  background: transparent;
}

/* ---------- chapters 02 and 03 ---------- */
.learn-ai-page .learn-lessons {
  font-family: var(--minimal-font);
}

.learn-ai-page .learn-lessons .learn-chapter-head {
  display: block;
  max-width: 820px;
  margin: 0 auto clamp(40px, 5vw, 64px);
  padding-top: 0;
  border-top: 0;
  text-align: center;
}

.learn-ai-page .learn-lessons .learn-chapter-number {
  position: static;
  margin-bottom: 8px;
  color: var(--minimal-soft);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: 0;
  line-height: 1.2;
}

.learn-ai-page .learn-lessons .learn-section-kicker {
  margin: 0 0 10px;
  color: var(--minimal-soft);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.01em;
  text-transform: none;
}

.learn-ai-page .learn-lessons .learn-chapter-head h2 {
  max-width: none;
  margin: 0;
  color: var(--minimal-ink);
  font-size: clamp(36px, 5.2vw, 56px);
  font-weight: 600;
  letter-spacing: -0.03em;
  line-height: 1.07;
}

.learn-ai-page .learn-lessons .lesson-stack {
  gap: 22px;
}

/* Each lesson is one white tile: the explanation beside its picture. */
.learn-ai-page .learn-lessons .lesson-row {
  gap: clamp(28px, 4vw, 56px);
  padding: clamp(28px, 4vw, 52px);
  border-radius: 28px;
  background: var(--minimal-tile);
}

.learn-ai-page .learn-lessons .explanation-text {
  color: var(--minimal-muted);
  font-size: clamp(17px, 1.5vw, 19px);
  letter-spacing: -0.01em;
  line-height: 1.55;
}

.learn-ai-page .learn-lessons .explanation-text strong {
  color: var(--minimal-ink);
  font-weight: 600;
}

.learn-ai-page .learn-lessons .explanation-text .example {
  color: var(--minimal-soft);
  font-style: normal;
}

.learn-ai-page .learn-lessons .faq-image {
  border-radius: 18px;
  box-shadow: none;
}

.learn-ai-page .learn-lessons .button-container {
  justify-content: flex-start;
  flex-wrap: wrap;
  gap: 12px;
  padding-left: 0;
}

.learn-ai-page .learn-lessons .lesson-stack > .button-container {
  justify-content: center;
  margin: 18px 0 0;
  padding-left: 0;
}

/* Lesson links: Apple's blue pill, with no gradients or hover images. */
.learn-ai-page .learn-lessons .btn-primary {
  display: inline-flex;
  align-items: center;
  margin: 0;
  padding: 11px 21px;
  border: 0;
  border-radius: 980px;
  background: var(--minimal-accent);
  background-image: none;
  color: #ffffff;
  font-family: var(--minimal-font);
  font-size: 15px;
  font-weight: 400;
  letter-spacing: -0.01em;
  text-decoration: none;
  box-shadow: none;
  transform: none;
  transition: background-color 0.2s ease;
}

.learn-ai-page .learn-lessons .btn-primary::before,
.learn-ai-page .learn-lessons .btn-primary::after {
  content: none;
}

.learn-ai-page .learn-lessons .btn-primary:hover,
.learn-ai-page .learn-lessons .btn-primary:focus-visible {
  background: var(--minimal-accent-hover);
  color: #ffffff;
  box-shadow: none;
  transform: none;
}

.learn-ai-page .learn-lessons .btn-primary:focus-visible {
  outline: 2px solid var(--minimal-accent);
  outline-offset: 3px;
}

/* ---------- chapter switcher at the bottom ---------- */
.learn-ai-page .learn-waypoints {
  border: 0;
  background: rgba(255, 255, 255, 0.78);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  box-shadow: 0 4px 24px rgba(0, 0, 0, 0.1);
  font-family: var(--minimal-font);
}

.learn-ai-page .learn-waypoints a {
  color: var(--minimal-muted);
  font-weight: 500;
}

.learn-ai-page .learn-waypoints a:hover {
  color: var(--minimal-ink);
  background: rgba(0, 0, 0, 0.04);
}

.learn-ai-page .learn-waypoints a.is-active {
  color: var(--minimal-ink);
  background: rgba(0, 0, 0, 0.06);
}

.learn-ai-page .learn-waypoints .wp-dot {
  background: var(--minimal-soft);
}

.learn-ai-page .learn-waypoints a.is-active .wp-dot {
  background: var(--minimal-accent);
  box-shadow: none;
}

/* ---------- smaller screens ---------- */
@media (max-width: 980px) {
  .learn-ai-page .learn-card {
    padding: 20px 22px;
  }

  .learn-ai-page .learn-card-icon {
    margin-top: 0;
  }

  .learn-ai-page .learn-card-arrow {
    top: auto;
    right: auto;
  }
}

@media (max-width: 700px) {
  .learn-ai-page .learn-cover {
    padding: 48px 16px 40px;
  }

  .learn-ai-page .learn-lessons .lesson-row {
    padding: 24px 20px;
    border-radius: 22px;
  }

  .learn-ai-page .learn-lessons .button-container .btn-primary {
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  .learn-ai-page .learn-card,
  .learn-ai-page .learn-lessons .btn-primary {
    transition: none;
  }

  .learn-ai-page .learn-card:hover,
  .learn-ai-page .learn-card:focus-visible {
    transform: none;
  }
}