:root {
  color-scheme: light dark;
  --page: light-dark(#f4f1e9, #111716);
  --surface: light-dark(#fffdf8, #19201f);
  --surface-soft: light-dark(#ece8dd, #232c2a);
  --text: light-dark(#18201e, #f2f6f3);
  --muted: light-dark(#5d6965, #aebbb7);
  --line: light-dark(#d5d0c4, #35423f);
  --accent: light-dark(#176b5a, #70d0b6);
  --accent-strong: light-dark(#0d4d40, #9ae6d1);
  --warm: light-dark(#bf6b3b, #f0a779);
  --shadow: 0 22px 60px light-dark(rgba(45, 54, 50, 0.10), rgba(0, 0, 0, 0.28));
  font-family: Inter, "Hiragino Sans", "Yu Gothic", Meiryo, sans-serif;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  margin: 0;
  background:
    radial-gradient(circle at 8% 3%, light-dark(rgba(23, 107, 90, 0.12), rgba(112, 208, 182, 0.09)), transparent 33rem),
    radial-gradient(circle at 92% 30%, light-dark(rgba(191, 107, 59, 0.08), rgba(240, 167, 121, 0.06)), transparent 28rem),
    var(--page);
  color: var(--text);
  line-height: 1.7;
}

a {
  color: inherit;
}

.skip-link {
  position: absolute;
  top: -5rem;
  left: 1rem;
  z-index: 10;
  padding: 0.7rem 1rem;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
}

.skip-link:focus {
  top: 1rem;
}

.home-shell {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 28px 0 72px;
}

.site-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 0.9rem;
  font-weight: 750;
  letter-spacing: 0.02em;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  background: var(--accent);
  border-radius: 10px 10px 10px 2px;
  color: var(--page);
  font-size: 0.9rem;
}

.course-count {
  padding: 5px 11px;
  background: var(--surface-soft);
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.76rem;
  font-weight: 700;
}

.intro {
  max-width: 820px;
  padding: clamp(72px, 12vw, 136px) 0 clamp(64px, 9vw, 104px);
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--accent-strong);
  font-size: 0.76rem;
  font-weight: 800;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 0;
  font-size: clamp(3rem, 9vw, 6.6rem);
  font-weight: 760;
  letter-spacing: -0.065em;
  line-height: 0.98;
}

.intro-copy {
  max-width: 600px;
  margin: 28px 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.18rem);
}

.course-section {
  scroll-margin-top: 24px;
}

.section-heading {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 24px;
  margin-bottom: 24px;
}

.section-heading h2 {
  margin: 0;
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  letter-spacing: -0.04em;
  line-height: 1.1;
}

.section-heading > p {
  margin: 0 0 4px;
  color: var(--muted);
  font-size: 0.86rem;
}

.course-card {
  display: grid;
  grid-template-columns: minmax(300px, 0.95fr) minmax(0, 1.05fr);
  overflow: hidden;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 24px;
  box-shadow: var(--shadow);
}

.course-image {
  position: relative;
  display: block;
  min-height: 420px;
  overflow: hidden;
  background: var(--surface-soft);
}

.course-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 360ms ease;
}

.course-image:hover img,
.course-image:focus-visible img {
  transform: scale(1.025);
}

.course-status {
  position: absolute;
  top: 18px;
  left: 18px;
  padding: 6px 12px;
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  border: 1px solid color-mix(in srgb, var(--line) 75%, transparent);
  border-radius: 999px;
  backdrop-filter: blur(10px);
  font-size: 0.75rem;
  font-weight: 800;
}

.course-content {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: clamp(28px, 5vw, 58px);
}

.course-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.course-meta span {
  padding: 4px 9px;
  background: var(--surface-soft);
  border-radius: 7px;
  color: var(--muted);
  font-size: 0.75rem;
  font-weight: 700;
}

.course-content h3 {
  margin: 22px 0 12px;
  font-size: clamp(2rem, 4vw, 3.5rem);
  letter-spacing: -0.05em;
  line-height: 1.05;
}

.course-content > p {
  margin: 0;
  color: var(--muted);
}

.course-topics {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
  margin: 22px 0 32px;
  padding: 0;
  list-style: none;
  font-size: 0.84rem;
  font-weight: 700;
}

.course-topics li::before {
  content: "•";
  margin-right: 7px;
  color: var(--warm);
}

.primary-link {
  display: inline-flex;
  min-height: 48px;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-top: auto;
  padding: 10px 18px;
  background: var(--accent);
  border-radius: 12px;
  color: var(--page);
  font-weight: 800;
  text-decoration: none;
  transition: background 160ms ease, transform 160ms ease;
}

.primary-link:hover,
.primary-link:focus-visible {
  background: var(--accent-strong);
  transform: translateY(-1px);
}

.site-footer {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
  padding: 22px 0 36px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 0.8rem;
}

.site-footer p {
  margin: 0;
}

@media (max-width: 760px) {
  .home-shell {
    padding-top: 20px;
  }

  .brand > span:last-child {
    display: none;
  }

  .intro {
    padding-top: 72px;
  }

  .section-heading {
    display: block;
  }

  .section-heading > p {
    margin-top: 10px;
  }

  .course-card {
    grid-template-columns: 1fr;
  }

  .course-image {
    min-height: 250px;
    aspect-ratio: 16 / 9;
  }
}

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

  .course-image img,
  .primary-link {
    transition: none;
  }
}