:root {
  --color-text: #1f2328;
  --color-text-muted: #59636e;
  --color-text-subtle: #6e7781;
  --color-border: #d8dee4;
  --color-surface: #ffffff;
  --color-surface-selected: #f0f2f4;
  --color-surface-hover: #f6f8fa;
  --color-accent: #0969da;

  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --nav-width: 15rem;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  background-color: var(--color-surface);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.5;
}

.page {
  margin: 0 auto;
  max-width: 68rem;
}

.page__header {
  padding: var(--space-6) var(--space-6) var(--space-5);
}

.page__title {
  margin: 0;
  font-size: 1.5rem;
  font-weight: 600;
}

.page__subtitle {
  margin: var(--space-1) 0 0;
  color: var(--color-text-muted);
}

.layout {
  display: grid;
  grid-template-columns: var(--nav-width) minmax(0, 1fr);
  border-top: 1px solid var(--color-border);
}

/* Release navigation */

.release-nav {
  border-right: 1px solid var(--color-border);
  padding: var(--space-4) 0;
}

.release-nav__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.release-nav__link {
  display: block;
  padding: var(--space-3) var(--space-5);
  border-left: 3px solid transparent;
  color: inherit;
  text-decoration: none;
}

.release-nav__link:hover {
  background-color: var(--color-surface-hover);
}

.release-nav__link:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: -2px;
}

.release-nav__link[aria-current="true"] {
  background-color: var(--color-surface-selected);
  border-left-color: var(--color-text);
}

.release-nav__version {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  font-weight: 600;
}

.release-nav__date {
  display: block;
  color: var(--color-text-subtle);
  font-size: 0.875rem;
}

.badge {
  border: 1px solid var(--color-border);
  border-radius: 999px;
  color: var(--color-text-muted);
  font-size: 0.625rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  padding: 0.05rem 0.4rem;
  text-transform: uppercase;
}

/* Release details */

.release-details {
  padding: var(--space-6);
}

.release-details:focus {
  outline: none;
}

.release__version {
  margin: 0;
  font-size: 1.75rem;
  font-weight: 600;
}

.release__date {
  margin: var(--space-2) 0 0;
  color: var(--color-text-subtle);
  font-size: 0.875rem;
}

.release__summary {
  margin: var(--space-4) 0 0;
  color: var(--color-text-muted);
}

.release__divider {
  border: 0;
  border-top: 1px solid var(--color-border);
  margin: var(--space-5) 0;
}

.change-group {
  margin-bottom: var(--space-6);
}

.change-group__label {
  margin: 0 0 var(--space-3);
  color: var(--color-text-muted);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.change-group__list {
  margin: 0;
  padding-left: 1.25rem;
}

.change {
  margin-bottom: var(--space-3);
}

.change__title {
  margin: 0;
}

.change__description {
  margin: var(--space-1) 0 0;
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

/* Media */

.media {
  display: grid;
  gap: var(--space-3);
  list-style: none;
  margin: var(--space-3) 0 var(--space-4);
  max-width: 34rem;
  padding: 0;
}

.media__figure {
  margin: 0;
}

.media__image,
.media__video {
  border: 1px solid var(--color-border);
  border-radius: 6px;
  display: block;
  max-width: 100%;
  height: auto;
}

.media__caption {
  color: var(--color-text-subtle);
  font-size: 0.8125rem;
  margin-top: var(--space-1);
}

/* Status messages */

.status {
  color: var(--color-text-muted);
}

.status--error {
  color: #b35900;
}

@media (max-width: 40rem) {
  .layout {
    grid-template-columns: minmax(0, 1fr);
  }

  .release-nav {
    border-right: 0;
    border-bottom: 1px solid var(--color-border);
  }

  .page__header,
  .release-details {
    padding: var(--space-5) var(--space-4);
  }

  .release-nav__link {
    padding-inline: var(--space-4);
  }
}