:root {
  --ink: #262626;
  --paper: #ffffff;
  --line: #cdcdcd;
  --highlight: #ebebeb;
  --muted: rgba(38, 38, 38, 0.18);
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: "Open Sans", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
}

.topbar {
  height: 72px;
  padding: 0 max(24px, calc((100vw - var(--max)) / 2));
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--ink);
  color: #ffffff;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  color: #ffffff;
  text-decoration: none;
}

.brand-logo {
  width: 42px;
  height: 42px;
  display: block;
  object-fit: cover;
}

.brand-title {
  font-size: 18px;
  font-weight: 800;
  letter-spacing: -0.02em;
}

.byline {
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0.01em;
}

.hero {
  min-height: calc(100vh - 72px);
  display: grid;
  place-items: center;
  padding: 80px 24px;
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  width: min(920px, 100%);
  text-align: center;
}

h1,
p {
  margin-top: 0;
}

.grade-stage {
  display: grid;
  grid-template-columns: minmax(90px, 1fr) auto minmax(90px, 1fr);
  align-items: center;
  gap: clamp(14px, 4vw, 42px);
}

.grade-column {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: clamp(24px, 4vw, 40px);
  font-weight: 800;
  letter-spacing: -0.04em;
  color: var(--muted);
  line-height: 1;
  user-select: none;
}

.grade-column-left {
  align-items: flex-end;
  text-align: right;
}

.grade-column-right {
  align-items: flex-start;
  text-align: left;
}

h1 {
  margin: 0;
  font-size: clamp(78px, 15vw, 172px);
  line-height: 0.92;
  font-weight: 800;
  letter-spacing: -0.08em;
}

.highlight {
  display: inline;
  padding: 0 0.14em 0.05em;
  background: var(--highlight);
  box-decoration-break: clone;
  -webkit-box-decoration-break: clone;
}

.intro-group {
  max-width: 580px;
  margin: 56px auto 34px;
}

.intro {
  margin: 0;
  font-size: clamp(17px, 2vw, 20px);
  line-height: 1.35;
}

.intro + .intro {
  margin-top: 4px;
}

.download-links {
  width: min(520px, 100%);
  margin: 0 auto;
  border-top: 1px solid var(--line);
}

.download-links a {
  min-height: 56px;
  padding: 0 4px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  text-decoration: none;
  font-size: 15px;
  transition: background-color 140ms ease, padding 140ms ease;
}

.download-links a:hover,
.download-links a:focus-visible {
  padding-left: 12px;
  padding-right: 12px;
  background: var(--highlight);
  outline: none;
}

.primary-link {
  font-weight: 700;
}

.secondary-link {
  font-weight: 600;
}

.footer {
  width: min(calc(100% - 48px), var(--max));
  min-height: 100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  font-size: 13px;
  font-weight: 600;
}

.footer a {
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

@media (max-width: 760px) {
  .topbar {
    height: 64px;
    padding: 0 18px;
  }

  .brand-logo {
    width: 36px;
    height: 36px;
  }

  .hero {
    min-height: calc(100vh - 64px);
    padding: 72px 20px;
  }

  .grade-stage {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  .grade-column {
    flex-direction: row;
    justify-content: center;
    gap: 16px;
    font-size: 24px;
  }

  .grade-column-left,
  .grade-column-right {
    align-items: center;
    text-align: center;
  }

  .grade-column-left {
    order: 1;
  }

  h1 {
    order: 2;
    font-size: clamp(72px, 28vw, 116px);
  }

  .grade-column-right {
    order: 3;
  }

  .intro-group {
    margin-top: 40px;
    margin-bottom: 28px;
  }

  .footer {
    width: calc(100% - 48px);
    min-height: 84px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .download-links a {
    transition: none;
  }
}