@layer reset, base, layout, components, utilities;

@layer reset {
  *, *::before, *::after { box-sizing: border-box; margin: 0; }

  html {
    color-scheme: light dark;
    text-size-adjust: 100%;
  }

  body {
    min-block-size: 100dvh;
    line-height: 1.6;
  }

  h1, h2, h3, p, li { overflow-wrap: break-word; }

  ul {
    padding: 0;
    list-style: none;
  }
}

@layer base {
  :root {
    --pg-color-surface: light-dark(oklch(98% 0.006 250), oklch(20% 0.02 255));
    --pg-color-raised: light-dark(oklch(100% 0 0), oklch(25% 0.022 255));
    --pg-color-text: light-dark(oklch(25% 0.03 255), oklch(94% 0.01 250));
    --pg-color-muted: light-dark(oklch(46% 0.03 255), oklch(76% 0.02 250));
    --pg-color-border: light-dark(oklch(85% 0.015 250), oklch(40% 0.025 255));
    --pg-color-accent: light-dark(oklch(46% 0.15 255), oklch(80% 0.11 250));
    --pg-color-reads: light-dark(oklch(42% 0.1 165), oklch(82% 0.12 165));
    --pg-color-writes: light-dark(oklch(45% 0.14 50), oklch(82% 0.12 70));
    --pg-space-xs: 0.25rem;
    --pg-space-sm: 0.5rem;
    --pg-space-md: 1rem;
    --pg-space-lg: 1.5rem;
    --pg-space-xl: 2.5rem;
    --pg-radius: 0.5rem;
    --pg-measure: 65ch;
    /* 44 CSS px, the recommended touch target */
    --pg-target: 2.75rem;
  }

  body {
    font-family: system-ui, sans-serif;
    color: var(--pg-color-text, CanvasText);
    background: var(--pg-color-surface, Canvas);
  }

  h1, h2, h3 {
    line-height: 1.2;
    text-wrap: balance;
  }

  p { text-wrap: pretty; }

  a {
    color: var(--pg-color-accent, LinkText);
    text-underline-offset: 0.15em;
  }

  :focus-visible {
    outline: 2px solid var(--pg-color-accent, Highlight);
    outline-offset: 2px;
  }
}

@layer layout {
  body {
    display: flex;
    flex-direction: column;
  }

  .pg-header, .pg-gallery, .pg-footer {
    inline-size: min(100% - 2 * var(--pg-space-md, 1rem), 70rem);
    margin-inline: auto;
  }

  .pg-header { padding-block: var(--pg-space-xl, 2.5rem) var(--pg-space-lg, 1.5rem); }

  .pg-main { flex: 1; }

  .pg-footer { padding-block: var(--pg-space-xl, 2.5rem) var(--pg-space-lg, 1.5rem); }

  .pg-cards {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 18rem), 1fr));
    gap: var(--pg-space-md, 1rem);
  }

  /* The header and footer are hidden while a tool is staged, so the stage owns the viewport. */
  .pg-stage {
    display: grid;
    grid-template-rows: auto 1fr;
    block-size: 100dvh;
  }

  .pg-stage-bar {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--pg-space-xs, 0.25rem) var(--pg-space-md, 1rem);
    padding: var(--pg-space-xs, 0.25rem) var(--pg-space-md, 1rem);
  }

  .pg-stage-view { min-block-size: 0; }
}

@layer components {
  .pg-title {
    font-size: clamp(2rem, 1.2rem + 3.5vw, 3.25rem);
    letter-spacing: -0.02em;
  }

  .pg-tagline {
    max-inline-size: var(--pg-measure, 65ch);
    margin-block-start: var(--pg-space-sm, 0.5rem);
    font-size: 1.125rem;
    color: var(--pg-color-muted, GrayText);
  }

  .pg-gallery-heading { font-size: 1.25rem; }

  .pg-status {
    margin-block-end: var(--pg-space-md, 1rem);
    color: var(--pg-color-muted, GrayText);
  }

  .pg-card {
    position: relative;
    display: flex;
    flex-direction: column;
    gap: var(--pg-space-sm, 0.5rem);
    padding: var(--pg-space-lg, 1.5rem);
    background: var(--pg-color-raised, Canvas);
    border: 1px solid var(--pg-color-border, ButtonBorder);
    border-radius: var(--pg-radius, 0.5rem);
    transition: translate 150ms ease-out;

    &:hover {
      translate: 0 -2px;
      border-color: var(--pg-color-accent, LinkText);
    }

    /* The link's own ring is moved out to the whole card. */
    &:has(.pg-card-link:focus-visible) {
      outline: 2px solid var(--pg-color-accent, Highlight);
      outline-offset: 2px;
    }
  }

  .pg-card-head {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: var(--pg-space-xs, 0.25rem) var(--pg-space-sm, 0.5rem);
  }

  .pg-card-title { font-size: 1.25rem; }

  .pg-card-link {
    color: inherit;
    text-decoration: none;

    /* Stretches the link so the whole card is the target. */
    &::after {
      content: "";
      position: absolute;
      inset: 0;
    }

    &:focus-visible { outline: none; }
  }

  .pg-card-description {
    flex: 1;
    color: var(--pg-color-muted, GrayText);
  }

  .pg-card-tags {
    display: flex;
    flex-wrap: wrap;
    gap: var(--pg-space-xs, 0.25rem);
  }

  .pg-tag {
    padding-inline: 0.6em;
    font-size: 0.8125rem;
    color: var(--pg-color-muted, GrayText);
    border: 1px solid var(--pg-color-border, ButtonBorder);
    border-radius: 1em;
  }

  .pg-card-meta {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: var(--pg-space-xs, 0.25rem) var(--pg-space-sm, 0.5rem);
    font-size: 0.8125rem;
    color: var(--pg-color-muted, GrayText);
  }

  .pg-badge {
    padding-inline: 0.6em;
    font-size: 0.8125rem;
    font-weight: 600;
    white-space: nowrap;
    color: var(--pg-color-reads, CanvasText);
    border: 1px solid currentColor;
    border-radius: 1em;
  }

  .pg-badge-writes { color: var(--pg-color-writes, CanvasText); }

  .pg-button {
    display: inline-flex;
    align-items: center;
    min-block-size: var(--pg-target, 2.75rem);
    padding-inline: 1em;
    font-weight: 600;
    text-decoration: none;
    border: 1px solid var(--pg-color-accent, LinkText);
    border-radius: var(--pg-radius, 0.5rem);
  }

  .pg-stage-bar {
    background: var(--pg-color-raised, Canvas);
    border-block-end: 1px solid var(--pg-color-border, ButtonBorder);
  }

  /* Grows to push the links to the far edge, and wraps them below on a narrow screen. */
  .pg-stage-title {
    flex: 1 1 8rem;
    font-size: 1.125rem;

    /* Focused by script so screen readers announce the tool; it is not a control. */
    &:focus-visible { outline: none; }
  }

  .pg-stage-link {
    display: inline-flex;
    align-items: center;
    min-block-size: var(--pg-target, 2.75rem);
    font-size: 0.9375rem;
  }

  /* Tools expect a light page behind them unless they say otherwise. */
  .pg-stage-frame {
    display: block;
    inline-size: 100%;
    block-size: 100%;
    color-scheme: light;
    background: Canvas;
    border: 0;
  }

  .pg-footer {
    display: grid;
    gap: var(--pg-space-sm, 0.5rem);
    font-size: 0.9375rem;
    color: var(--pg-color-muted, GrayText);
  }
}

@layer utilities {
  /* Last layer, so the hidden attribute beats any display set above. */
  :where([hidden]) { display: none; }

  @media (prefers-reduced-motion: reduce) {
    *, *::before, *::after {
      animation-duration: 0.01ms !important;
      animation-iteration-count: 1 !important;
      transition-duration: 0.01ms !important;
      scroll-behavior: auto !important;
    }
  }
}