* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --line: rgba(0, 0, 0, 0.1);
  --muted: rgba(0, 0, 0, 0.4);
}

html {
  font-size: 16px;
}

body {
  font-family:
    'Geist', ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background: #fff;
  color: #000;
  line-height: 1.5;
}

a {
  color: inherit;
  text-decoration: none;
}

main {
  min-height: 100vh;
  max-width: 42rem;
  margin: 0 auto;
  padding: 2.5rem 1.5rem 4rem;
  display: flex;
  flex-direction: column;
}

header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 5rem;
}

h1 {
  font-size: 1.5rem;
  line-height: 2rem;
  font-weight: 700;
  letter-spacing: -0.025em;
}

.header-text p {
  margin-top: 0.5rem;
  font-size: 0.875rem;
  line-height: 1.25rem;
  color: var(--muted);
}

.download-link {
  flex-shrink: 0;
  font-size: 0.875rem;
  line-height: 1.25rem;
  color: rgba(0, 0, 0, 0.3);
  white-space: nowrap;
  transition: color 0.2s;
}

.download-link:hover {
  color: rgba(0, 0, 0, 0.6);
}

.intro {
  margin-bottom: 1.5rem;
  font-size: 0.875rem;
  line-height: 1.25rem;
  color: var(--muted);
  word-break: keep-all;
}

ul.feature-list {
  flex: 1;
  list-style: none;
  border-top: 1px solid var(--line);
}

ul.feature-list li + li {
  margin-top: 1px;
}

.feature-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem 0;
  border-bottom: 1px solid var(--line);
  transition: border-color 0.2s;
}

.feature-item:hover {
  border-color: rgba(0, 0, 0, 0.3);
}

.feature-title {
  font-size: 1rem;
  line-height: 1.5rem;
  font-weight: 500;
  color: #000;
  transition: color 0.2s;
}

.feature-item:hover .feature-title {
  color: rgba(0, 0, 0, 0.7);
}

.feature-desc {
  margin-top: 0.25rem;
  font-size: 0.875rem;
  line-height: 1.25rem;
  color: var(--muted);
  word-break: keep-all;
}

footer {
  margin-top: 5rem;
  font-size: 0.75rem;
  line-height: 1rem;
  color: rgba(0, 0, 0, 0.2);
}

.back-link {
  display: block;
  margin-bottom: 0.375rem;
  font-size: 0.75rem;
  color: rgba(0, 0, 0, 0.3);
  transition: color 0.2s;
}

.back-link:hover {
  color: rgba(0, 0, 0, 0.6);
}

.header-nav {
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.nav-link {
  font-size: 0.875rem;
  line-height: 1.25rem;
  color: rgba(0, 0, 0, 0.3);
  transition: color 0.2s;
  white-space: nowrap;
}

.nav-link:hover {
  color: rgba(0, 0, 0, 0.7);
}

.release-list {
  flex: 1;
}

.release-sticky-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: #fff;
  padding-top: 2rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--line);
  display: flex;
  align-items: baseline;
  gap: 0.75rem;
}

.release-version {
  font-size: 1rem;
  font-weight: 700;
  color: rgba(0, 0, 0, 0.6);
}

.release-date {
  font-size: 0.8125rem;
  color: var(--muted);
}

.release-changes {
  list-style: none;
}

.change-item {
  display: flex;
  align-items: baseline;
  gap: 0.625rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--line);
  font-size: 0.875rem;
  line-height: 1.4;
  color: var(--muted);
  word-break: keep-all;
}

.change-tag {
  flex-shrink: 0;
  font-size: 0.625rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  padding: 0.15rem 0.4rem;
  border-radius: 3px;
}

.tag-new { background: #e8f5e9; color: #2e7d32; }
.tag-fix { background: #fff3e0; color: #e65100; }
.tag-chg { background: #f3f3f3; color: #555; }

@media (max-width: 640px) {
  main {
    padding: 1.5rem 1rem 3rem;
  }

  header {
    margin-bottom: 3.75rem;
  }
}