:root {
  color-scheme: light;
  font-family:
    ui-rounded, "SF Pro Rounded", "Avenir Next", system-ui, -apple-system,
    BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-synthesis: none;
  --ink: #15253d;
  --muted: #64748b;
  --blue: #2563eb;
  --surface: #ffffff;
  --line: #d7e0eb;
  --green: #087154;
}

* {
  box-sizing: border-box;
}

html,
body {
  min-height: 100%;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 8% 5%, rgb(37 99 235 / 8%), transparent 28rem),
    #f4f7fb;
  overscroll-behavior: none;
}

a {
  -webkit-tap-highlight-color: transparent;
}

.home-shell {
  width: min(100%, 1280px);
  margin: 0 auto;
  padding:
    max(28px, env(safe-area-inset-top))
    max(24px, env(safe-area-inset-right))
    max(34px, env(safe-area-inset-bottom))
    max(24px, env(safe-area-inset-left));
}

.home-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: clamp(42px, 7vw, 88px);
}

.grade-label {
  margin: 0 0 8px;
  color: var(--blue);
  font-size: clamp(1rem, 1.8vw, 1.25rem);
  font-weight: 850;
  letter-spacing: 0.01em;
}

h1,
h2 {
  margin: 0;
  letter-spacing: -0.04em;
}

h1 {
  font-size: clamp(2.25rem, 6vw, 5.25rem);
  line-height: 0.98;
}

.home-subtitle {
  margin: 12px 0 0;
  color: var(--muted);
  font-size: clamp(1.15rem, 2.3vw, 1.7rem);
  font-weight: 700;
}

.local-note {
  flex: 0 0 auto;
  margin: 5px 0 0;
  padding: 9px 14px;
  border: 1px solid #b9e5d5;
  border-radius: 999px;
  color: var(--green);
  background: #ecfdf5;
  font-size: clamp(0.75rem, 1.3vw, 0.92rem);
  font-weight: 750;
  white-space: nowrap;
}

.local-note span,
.module-status span {
  margin-right: 5px;
  font-size: 0.72em;
}

.chapter-heading {
  margin-bottom: 18px;
}

.chapter + .chapter {
  margin-top: clamp(42px, 6vw, 74px);
}

h2 {
  font-size: clamp(2rem, 4.5vw, 3.4rem);
  line-height: 1;
}

.module-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: clamp(16px, 2.5vw, 28px);
}

.chapter-rationale .module-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.chapter-rationale .module-card {
  grid-column: span 2;
}

.chapter-terms .module-grid {
  grid-template-columns: repeat(6, minmax(0, 1fr));
}

.chapter-terms .module-card {
  grid-column: span 2;
}

.chapter-equations .module-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.chapter-quadrilaterals .module-grid {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

.chapter-quadrilaterals .module-card {
  grid-column: auto;
}

.chapter-assignments .module-grid {
  grid-template-columns: repeat(6, minmax(0, 1fr));
}

.chapter-assignments .module-card {
  grid-column: span 2;
}

.chapter-percentages .module-grid {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.chapter-percentages .module-card {
  grid-column: auto;
}

.chapter-probability .module-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.chapter-probability .module-card {
  grid-column: auto;
}

.module-card {
  display: flex;
  min-height: clamp(220px, 28vw, 330px);
  padding: clamp(24px, 3.6vw, 44px);
  border: 1px solid var(--line);
  border-radius: clamp(24px, 3vw, 34px);
  color: inherit;
  background: rgb(255 255 255 / 94%);
  box-shadow: 0 22px 70px rgb(30 41 59 / 10%);
  flex-direction: column;
  text-decoration: none;
  touch-action: manipulation;
}

.module-status {
  align-self: flex-start;
  margin-bottom: auto;
  padding: 7px 11px;
  border-radius: 999px;
  color: var(--green);
  background: #ecfdf5;
  font-size: clamp(0.78rem, 1.3vw, 0.94rem);
  font-weight: 800;
}

.module-title {
  max-width: 18ch;
  font-size: clamp(1.5rem, 2.7vw, 2.65rem);
  font-weight: 900;
  letter-spacing: -0.035em;
  line-height: 1.04;
}

.module-subtitle {
  margin-top: 10px;
  color: var(--muted);
  font-size: clamp(1rem, 1.8vw, 1.3rem);
  font-weight: 700;
}

.module-card:focus-visible {
  outline: 5px solid rgb(37 99 235 / 32%);
  outline-offset: 5px;
}

.module-card:active {
  transform: scale(0.985);
}

noscript {
  display: block;
  margin-top: 18px;
  color: #a6384d;
  font-weight: 700;
}

@media (max-width: 720px) {
  .home-shell {
    padding-inline: 14px;
  }

  .home-header {
    display: block;
    margin-bottom: 42px;
  }

  .local-note {
    display: inline-block;
    margin-top: 14px;
  }

  .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-rationale .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-rationale .module-card {
    grid-column: auto;
  }

  .chapter-terms .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-terms .module-card {
    grid-column: auto;
  }

  .chapter-equations .module-grid {
    grid-template-columns: 1fr;
    width: 100%;
  }

  .chapter-quadrilaterals .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-assignments .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-assignments .module-card {
    grid-column: auto;
  }

  .chapter-percentages .module-grid {
    grid-template-columns: 1fr;
  }

  .chapter-probability .module-grid {
    grid-template-columns: 1fr;
  }

  .module-card {
    min-height: 210px;
  }
}

@media (min-width: 721px) and (max-width: 1040px) {
  .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-rationale .module-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .chapter-rationale .module-card {
    grid-column: span 2;
  }

  .chapter-terms .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-terms .module-card {
    grid-column: auto;
  }

  .chapter-equations .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-assignments .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-assignments .module-card {
    grid-column: auto;
  }

  .chapter-percentages .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-percentages .module-card:nth-child(5) {
    grid-column: span 2;
  }

  .chapter-probability .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-probability .module-card {
    grid-column: auto;
  }

}

@media (orientation: landscape) and (min-width: 900px) and (max-width: 1500px) {
  .home-shell {
    padding-top: max(24px, env(safe-area-inset-top));
    padding-bottom: max(22px, env(safe-area-inset-bottom));
  }

  .home-header {
    margin-bottom: 20px;
  }

  h1 {
    font-size: clamp(2.1rem, 4vw, 3.4rem);
  }

  .home-subtitle {
    margin-top: 7px;
    font-size: clamp(1rem, 1.6vw, 1.35rem);
  }

  .chapter-heading {
    margin-bottom: 12px;
  }

  .grade-label {
    margin-bottom: 4px;
    font-size: clamp(0.92rem, 1.2vw, 1.05rem);
  }

  h2 {
    font-size: clamp(1.8rem, 2.8vw, 2.45rem);
  }

  .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    grid-auto-rows: 1fr;
    gap: clamp(14px, 1.8vw, 22px);
  }

  .chapter-rationale .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
    grid-auto-rows: 1fr;
  }

  .chapter-terms .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .chapter-assignments .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .chapter-percentages .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .chapter-percentages .module-card {
    grid-column: span 2;
  }

  .chapter-equations .module-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .chapter-equations .module-card {
    grid-column: span 2;
  }

  .chapter-equations .module-card:nth-child(4) {
    grid-column: span 2;
  }

  .module-card {
    grid-column: span 2;
    min-height: clamp(218px, 22vh, 232px);
    padding: clamp(16px, 1.7vw, 24px);
    border-radius: clamp(20px, 2.2vw, 28px);
  }

  .module-card:nth-child(4) {
    grid-column: 1 / span 2;
  }

  .module-card:nth-child(5) {
    grid-column: 3 / span 2;
  }

  .module-card:nth-child(6) {
    grid-column: 5 / span 2;
  }

  .chapter-percentages .module-card:nth-child(n) {
    grid-column: span 2;
  }

  .chapter-percentages .module-card:nth-child(4) {
    grid-column: 2 / span 2;
  }

  .chapter-percentages .module-card:nth-child(5) {
    grid-column: 4 / span 2;
  }

  .chapter-probability .module-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .chapter-probability .module-card {
    grid-column: auto;
  }

  .chapter-probability .module-card:nth-child(3) {
    grid-column: auto;
  }

  .chapter-rationale .module-card {
    grid-column: span 2;
  }

  .chapter-terms .module-card {
    grid-column: span 2;
  }

  .chapter-assignments .module-card {
    grid-column: span 2;
  }

  .module-status {
    margin-bottom: clamp(11px, 1.4vw, 16px);
    padding: 6px 10px;
    font-size: clamp(0.76rem, 1.05vw, 0.88rem);
  }

  .module-title {
    max-width: none;
    font-size: clamp(1.2rem, 1.9vw, 1.7rem);
    line-height: 1.08;
  }

  .module-subtitle {
    margin-top: 7px;
    font-size: clamp(0.94rem, 1.35vw, 1.12rem);
  }
}

@media (orientation: landscape) and (min-width: 1501px) {
  .chapter-rationale .module-grid {
    grid-template-columns: repeat(6, minmax(0, 1fr));
  }

  .chapter-rationale .module-card {
    grid-column: span 2;
  }

}

@media (prefers-reduced-motion: no-preference) {
  .module-card {
    transition:
      border-color 140ms ease,
      box-shadow 140ms ease,
      transform 90ms ease;
  }

  .module-card:hover {
    border-color: #aebed0;
    box-shadow: 0 26px 80px rgb(30 41 59 / 14%);
  }
}

.ausberlinos-backlink { margin: 0 0 18px; font: 500 14px/1.5 system-ui, sans-serif; }
.ausberlinos-backlink a { display: inline-flex; align-items: center; min-height: 44px; color: inherit; text-underline-offset: 4px; }
.ausberlinos-backlink a:focus-visible { outline: 2px solid currentColor; outline-offset: 4px; }