body.lessons-page {
  color-scheme: dark;
  margin: 0;
  background: #000;
  color: #f5f5f7;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
}
.lessons-page .site-header {
  width: min(1120px, calc(100% - 48px));
  margin: 0 auto;
  padding: 28px 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.lessons-page .brand { color: #f5f5f7; font-size: 18px; }
.lessons-page .brand-mark { width: 32px; height: 32px; border-radius: 9px; background: #f5f5f7; color: #000; font-size: 20px; transform: none; }
.lessons-back { color: #b6b6bd; text-decoration: none; font-size: 14px; white-space: nowrap; }
.lessons-back span { margin-inline-start: 7px; }
.lessons-back:hover { color: #fff; }
.lessons-main { width: min(1120px, calc(100% - 48px)); margin: 0 auto; padding-bottom: 100px; }
.lessons-hero { padding: 76px 0 80px; }
.lessons-eyebrow { color: #a3a3ad; font-size: 15px; font-weight: 600; letter-spacing: .02em; }
.lessons-hero h1 { margin: 18px 0 24px; font: 650 clamp(64px, 9vw, 112px)/1.03 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; letter-spacing: -.035em; }
.lessons-hero > p:not(.lessons-eyebrow) { max-width: 680px; color: #aaaab3; font-size: clamp(21px, 2.5vw, 28px); line-height: 1.5; letter-spacing: -.025em; }
.lessons-availability { display: block; margin-top: 24px; color: #86868f; font-size: 14px; line-height: 1.5; }
.lesson-section { margin: 0; padding-top: 30px;  }
.lesson-section + .lesson-section { margin-top: 64px; }
.lesson-section h2 { margin: 0 0 26px; font: 600 clamp(18px, 2vw, 22px)/1.3 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; letter-spacing: .08em; text-transform: uppercase; text-align: center; }
.lesson-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.lesson-section-secondary .lesson-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.lesson-card { position: relative; height: 100%; display: flex; flex-direction: column; padding: 26px 26px 42px; border: 1px solid #242428; border-radius: 22px; background: #111113; color: #f5f5f7; text-decoration: none; transition: background .2s, border-color .2s; }
.lesson-card:hover { background: #19191d; border-color: #50505a; }
.lesson-card:focus-visible, .lessons-back:focus-visible, .lessons-page .brand:focus-visible { outline: 3px solid #a9b9ff; outline-offset: 5px; }
.lesson-art { height: 138px; display: flex; align-items: center; justify-content: center; color: #bbb2f2; font-size: 78px; font-weight: 500; line-height: 1; letter-spacing: -.06em; }
.lesson-art-decimals { color: #9ec7c8; font-size: 66px; }
.lesson-art-percent { color: #ddc7a5; font-size: 86px; }
.lesson-art-logarithms { color: #aebff0; }
.lesson-art-trigonometry { color: #b5c6aa; }
.lesson-art svg { width: 160px; height: 110px; }
.lesson-fraction { display: grid; text-align: center; font-size: 38px; gap: 7px; }
.lesson-fraction > :first-child { padding: 0 12px 8px; border-bottom: 2px solid currentColor; }
.lesson-decimal-comma { color: #6d9193; }
.lesson-log { font-size: 48px; font-weight: 450; letter-spacing: -.045em; }
.lesson-log sub { font-size: 20px; position: relative; bottom: -.2em; }
.lesson-log > span { margin-inline-start: 10px; font-size: 42px; }
.lesson-card h3 { margin: 14px 0 12px; font: 600 22px/1.25 -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif; letter-spacing: -.025em; overflow-wrap: anywhere; }
.lesson-card p { margin: 0; color: #a7a7b0; font-size: 15px; line-height: 1.65; }
.lesson-card-arrow { position: absolute; right: 24px; bottom: 17px; color: #9c9ca8; font-size: 22px; }
[dir="rtl"] .lesson-card-arrow { right: auto; left: 24px; }
@media (max-width: 700px) {
  .lessons-page .site-header, .lessons-main { width: calc(100% - 40px); }
  .lessons-page .site-header { padding: 22px 0; gap: 12px; }
  .lessons-page .brand { gap: 8px; font-size: 15px; }
  .lessons-back { font-size: 12px; }
  .lessons-hero { padding: 52px 0 56px; }
  .lessons-hero h1 { font-size: clamp(54px, 12vw, 80px); }
  .lessons-hero > p:not(.lessons-eyebrow) { font-size: 21px; }
  .lesson-grid, .lesson-section-secondary .lesson-grid { grid-template-columns: minmax(0, 1fr); gap: 14px; }
  .lesson-card { display: grid; grid-template-columns: 68px minmax(0, 1fr); gap: 20px; padding: 24px 24px 50px 20px; border-radius: 18px; }
  .lesson-art { height: 90px; font-size: 50px; }
  .lesson-art-percent { font-size: 62px; }
  .lesson-art-decimals { font-size: 40px; }
  .lesson-art svg { width: 72px; height: 70px; }
  .lesson-fraction { font-size: 28px; }
  .lesson-log { font-size: 21px; }
  .lesson-log sub { font-size: 11px; }
  .lesson-log > span { display: block; margin: 7px 0 0; font-size: 25px; text-align: center; }
  .lesson-card h3 { margin: 0 0 10px; font-size: 20px; }
  .lesson-card p { font-size: 14px; }
  .lesson-section + .lesson-section { margin-top: 44px; }
}
@media (prefers-reduced-motion: reduce) { .lesson-card { transition: none; } }