/** Variables */

:root {
  --colour-primary-10: #060300;
  --colour-primary-15: #150800;
  --colour-primary-20: #1f1400;
  --colour-primary-30: #3c2b00;
  --colour-primary-40: #5c4300;
  --colour-primary-50: #7f5d00;
  --colour-primary-60: #a37800;
  --colour-primary-70: #c89500;
  --colour-primary-80: #efb300;
  --colour-primary-90: #ffd98c;
  --colour-primary-95: #ffecc8;

  --colour-hyperlink-10: #000409;
  --colour-hyperlink-20: #001829;
  --colour-hyperlink-30: #00314d;
  --colour-hyperlink-40: #004d75;
  --colour-hyperlink-50: #006a9f;
  --colour-hyperlink-60: #1388c9;
  --colour-hyperlink-70: #41a8ea;
  --colour-hyperlink-80: #78c7ff;
  --colour-hyperlink-90: #bfe3ff;
  --colour-hyperlink-95: #e0f1ff;

  --colour-grey-10: oklch(0.1 0.01 84);
  --colour-grey-20: oklch(0.2 0.01 84);
  --colour-grey-30: oklch(0.3 0.01 84);
  --colour-grey-40: oklch(0.4 0.01 84);
  --colour-grey-50: oklch(0.5 0.01 84);
  --colour-grey-60: oklch(0.6 0.01 84);
  --colour-grey-70: oklch(0.7 0.01 84);
  --colour-grey-80: oklch(0.8 0.01 84);
  --colour-grey-90: oklch(0.9 0.01 84);
  --colour-grey-95: oklch(0.95 0.01 84);

  --colour-error-10: oklch(0.1 0.2 26);
  --colour-error-20: oklch(0.2 0.2 26);
  --colour-error-30: oklch(0.3 0.2 26);
  --colour-error-40: oklch(0.4 0.2 26);
  --colour-error-50: oklch(0.5 0.2 26);
  --colour-error-60: oklch(0.6 0.2 26);
  --colour-error-70: oklch(0.7 0.2 26);
  --colour-error-80: oklch(0.8 0.2 26);
  --colour-error-90: oklch(0.9 0.2 26);
  --colour-error-95: oklch(0.95 0.2 26);

  --colour-warn-10: oklch(0.1 0.2 46);
  --colour-warn-20: oklch(0.2 0.2 46);
  --colour-warn-30: oklch(0.3 0.2 46);
  --colour-warn-40: oklch(0.4 0.2 46);
  --colour-warn-50: oklch(0.5 0.2 46);
  --colour-warn-60: oklch(0.6 0.2 46);
  --colour-warn-70: oklch(0.7 0.2 46);
  --colour-warn-80: oklch(0.8 0.2 46);
  --colour-warn-90: oklch(0.9 0.2 46);
  --colour-warn-95: oklch(0.95 0.2 46);

  --colour-primary-fg: var(--colour-primary-90);
  --colour-primary-fg-accent: var(--colour-primary-80);
  --colour-primary-bg: var(--colour-primary-10);
  --colour-primary-bg-accent: var(--colour-primary-20);
  --colour-code-fg: var(--colour-primary-90);
  --colour-code-bg: var(--colour-primary-15);
  --colour-hyperlink: var(--colour-hyperlink-80);
  --colour-grey-fg: var(--colour-grey-70);
  --colour-grey-bg: var(--colour-grey-30);
  --colour-error-fg: var(--colour-error-90);
  --colour-error-bg: var(--colour-error-40);
  --colour-warn-fg: var(--colour-warn-20);
  --colour-warn-bg: var(--colour-warn-80);

  --font-size-sm: 1rem;
  --font-size-base: 1.125rem;
  --font-size-md: 1.5rem;
  --font-size-lg: 2rem;
  --font-size-xl: 3rem;

  --spacing-block-xs: 0.5rem;
  --spacing-block-sm: 1.75rem;
  --spacing-block-md: 2.5rem;
  --spacing-block-lg: 3.5rem;
  --spacing-block-xl: 5rem;
  --spacing-inline-xs: 0.25rem;
  --spacing-inline-sm: 0.5rem;
  --spacing-inline-md: 1.5rem;
  --spacing-inline-lg: 3rem;
  --spacing-inline-xl: 6rem;
}

/** Light theme */
@media (prefers-color-scheme: light) {
  :root {
    --colour-primary-fg: var(--colour-primary-20);
    --colour-primary-fg-accent: var(--colour-primary-40);
    --colour-primary-bg: var(--colour-primary-95);
    --colour-hyperlink: var(--colour-hyperlink-40);
    --colour-grey-fg: var(--colour-grey-40);
    --colour-grey-bg: var(--colour-grey-80);
    --colour-error-fg: var(--colour-error-20);
    --colour-error-bg: var(--colour-error-80);
  }
}

/** Base typography */

body {
  font-size: var(--font-size-base);
  color: var(--colour-primary-fg);
  font-weight: light;
  background-color: var(--colour-primary-bg);
  line-height: 1.5;

  /* Geometric Humanist stack from https://modernfontstacks.com */
  font-family:
    Avenir, Montserrat, Corbel, 'URW Gothic', source-sans-pro, sans-serif;
}

small {
  font-size: var(--font-size-sm);
}

:is(p, h1, h2, h3, h4, h5, h6, hr, img, figure, ul, ol, blockquote) {
  margin-block-start: var(--spacing-block-sm);
}

hr {
  height: 2px;
}

/** Base layout */

body {
  --body-margin-inline-start: var(--spacing-inline-lg);
  --body-margin-inline-end: var(--body-margin-inline-start);
  --body-margin-block-end: var(--spacing-block-xl);
  margin-inline: var(--body-margin-inline-start) var(--body-margin-inline-end);
  margin-block-end: var(--body-margin-block-end);
}

:is(h1, h2, h3, h4, h5, h6) {
  text-align: center;
}

img {
  margin-inline: auto;
  height: auto;
}

@media (min-width: 60rem) {
  body {
    display: grid;
    grid-template-columns:
      [grid-start media-start]
      var(--grid-margin-inline)
      [media-end content-start]
      minmax(var(--grid-max-content-width), auto)
      [content-end grid-end];
    grid-auto-rows: max-content;
    column-gap: var(--spacing-block-sm);
    max-width: var(--grid-total-width);

    --body-margin-inline-end: 6rem;
    --grid-margin-inline: 6rem;
    --grid-total-width: 48rem;
    --grid-max-content-width: calc(
      var(--grid-total-width) - var(--body-margin-inline-start) -
        var(--grid-margin-inline) - var(--spacing-block-sm) -
        var(--grid-margin-inline)
    );
  }

  :is(main, article, nav) {
    display: grid;
    grid-column: grid;
    grid-template-columns: subgrid;

    > :is(section, header, aside, form) {
      display: grid;
      grid-template-columns: subgrid;
      grid-column: grid;

      > :not(.not-grid-content) {
        grid-column: content;
      }
    }
  }

  :is(h1, h2, h3, h4, h5, h6) {
    text-align: start;
  }
}

@media (min-width: 80rem) {
  body {
    grid-template-columns:
      [grid-start media-start]
      var(--grid-margin-inline)
      [media-end content-start]
      minmax(auto, var(--grid-max-content-width))
      [content-end margin-start]
      auto
      [margin-end grid-end];

    --grid-total-width: 80rem;
    --grid-max-content-width: 40rem;
  }
}

/** Headings */

h1 {
  font-size: var(--font-size-xl);
  font-weight: 900;
  margin-block-start: 0;
}

h2 {
  font-size: var(--font-size-lg);
  font-weight: 900;
  margin-block-start: var(--spacing-block-xl);
}

h3,
h4,
h5,
h6 {
  font-size: var(--font-size-md);
  font-weight: 600;
  margin-block-start: var(--spacing-block-lg);
}

/** Hyperlinks */

a:is(:link, :visited) {
  color: var(--colour-hyperlink);
  text-decoration: underline;
  display: inline;
}

a:hover {
  text-decoration: wavy;
}

/** Definition lists */
dl {
  margin-block-start: var(--spacing-block-md);
}

dl dt {
  font-weight: bold;
}

dl dd + dt {
  margin-block-start: var(--spacing-block-md);
}

/** figcaptions */

figcaption {
  font-size: var(--font-size-sm);
  font-style: italic;
  text-align: center;
}

/** Lists */

:is(ol, ul) {
  margin-inline-start: var(--spacing-inline-lg);
}

/** Navigation bar */

nav {
  margin-block: var(--spacing-block-sm);
}

nav ul {
  grid-column: media-start / content-end;
  display: flex;
  justify-content: center;
  gap: var(--spacing-inline-md);
  list-style: none;
  margin: 0;
}

@media (min-width: 36rem) {
  nav {
    display: grid;
    grid-template-columns: subgrid;
  }

  nav ul {
    justify-content: end;
  }
}

/** Emphasis */

strong {
  font-weight: bold;
  font-style: italic;
}

/** Blog feed */

.h-feed ul {
  list-style: none;
  margin-inline: 0;
}

/** Block quotes */
blockquote {
  padding-inline-start: var(--spacing-inline-lg);
  border-inline-start: 2px solid var(--colour-primary-fg);
  font-style: italic;
}

blockquote footer {
  font-style: initial;
}

blockquote :is(b, strong) {
  font-style: italic;
  font-weight: bold;
}

blockquote :is(i, em) {
  font-style: normal;
}

/** Small caps */
.small-caps {
  font-variant: small-caps;
}

/** Pre-formatted blocks */
pre {
  border: 2px solid var(--colour-primary-fg);
  border-radius: 2px;
  background-color: var(--colour-code-bg) !important;
  margin-block-start: var(--spacing-block-sm);
  padding-inline: var(--spacing-inline-sm);
  padding-block: var(--spacing-block-xs);
}

/** Code blocks */
code {
  border: 2px solid var(--colour-primary-fg);
  border-radius: 2px;
  padding-inline: var(--spacing-inline-xs);
  color: var(--colour-code-fg);
  background-color: var(--colour-code-bg);
  font-size: var(--font-size-sm);
}
pre code {
  border: none;
  border-radius: none;
  padding: none;
}

/* verse */
.verse {
  span {
    display: block;
  }
}
.verse--hanging-indents {
  span + span:not(.not-hanging) {
    margin-inline-start: var(--spacing-inline-md);
  }
}

/* block-comment */
block-comment {
  display: grid;
  grid-template-columns: subgrid;
  grid-column: grid;

  > * {
    grid-column: content;
  }

  > blockquote:last-of-type {
    padding-block: var(--spacing-block-sm);
    padding-inline: var(--spacing-inline-md);
    overflow-y: scroll;
    border: 2px solid var(--colour-primary-fg);
    --colour-scroll-shadow: color-mix(
      in srgb,
      var(--colour-primary-fg),
      transparent 20%
    );

    background:
      linear-gradient(var(--colour-primary-bg) 30%, transparent) center top,
      linear-gradient(transparent, var(--colour-primary-bg) 70%) center bottom,
      radial-gradient(
          farthest-side at 50% 0,
          var(--colour-scroll-shadow),
          transparent
        )
        center top,
      radial-gradient(
          farthest-side at 50% 100%,
          var(--colour-scroll-shadow),
          transparent
        )
        center bottom;
    background-repeat: no-repeat;
    background-size:
      100% 2rem,
      100% 2rem,
      100% 1rem,
      100% 1rem;
    background-attachment: local, local, scroll, scroll;

    > :first-child {
      margin-block-start: 0;
    }
  }
}

@media (min-width: 80rem) {
  block-comment > blockquote:last-of-type {
    grid-column: margin;
    max-height: 67vh;
  }
}

/* forms */
form {
  margin-inline: auto;
  max-width: max-content;

  :is(button, fieldset, input, label, object, output, select, textarea, img) {
    display: block;
  }

  label {
    margin-block-end: var(--spacing-block-xs);
  }

  * + :is(label, input[type='submit'], button) {
    margin-block-start: var(--spacing-block-md);
  }

  :is(input[type='submit'], input[type='button'], button) {
    padding-inline: var(--spacing-inline-sm);
    max-width: max-content;
    &:not(dialog *) {
      margin-inline-start: auto;
    }
  }

  :is(input[type='email'], input[type='text'], select) {
    max-width: 100%;
    width: 16rem;
  }

  textarea {
    max-width: 100%;
    width: 40rem;
  }
}

/* dialogs */

dialog {
  background: var(--colour-primary-bg-accent);
  border: 2px solid var(--colour-primary-fg-accent);
  bottom: auto;
  color: var(--colour-primary-fg);
  left: calc(0.5 * (100vw - min(90vw, 36rem)));
  margin: 0;
  padding-block: var(--spacing-block-sm);
  padding-inline: var(--spacing-inline-sm);
  text-align: center;
  top: auto;
  width: min(90vw, 36rem);
}

@media (min-width: 80rem) {
  dialog {
    left: calc(
      var(--body-margin-inline-start) + var(--grid-margin-inline) + 2 *
        var(--spacing-inline-md)
    );
  }
}

/* utilities */
:is(
  .para-spacing-tight:is(p, h1, h2, h3, h4, h5, h6, hr, img, figure, ul, ol),
  .para-spacing-tight :is(p, h1, h2, h3, h4, h5, h6, hr, img, figure, ul, ol)
) {
  margin-block-start: var(--spacing-block-xs);
}

.error {
  background: var(--colour-error-bg);
  border: 2px solid var(--colour-error-fg);
  color: var(--colour-error-fg);
  padding-block: var(--spacing--block-sm);
  padding-inline: var(--spacing-inline-sm);
}

.warn {
  background: var(--colour-warn-bg);
  border: 2px solid var(--colour-warn-fg);
  color: var(--colour-warn-fg);
  padding-block: var(--spacing--block-sm);
  padding-inline: var(--spacing-inline-sm);
  --colour-hyperlink: var(--colour-hyperlink-40);
}
