NG: Add all styles from Furo, modulo colors

src/crate/theme/rtd/crate/static/vendor/furo/styles/base/_index.sass

@@ -1,4 +1,4 @@
-//@import "print"
+@import "print"
 @import "screen-readers"
 @import "theme"
-//@import "typography"
+@import "typography"

src/crate/theme/rtd/crate/static/vendor/furo/styles/base/_print.sass

@@ -0,0 +1,43 @@
+// This file contains styles for managing print media.
+
+////////////////////////////////////////////////////////////////////////////////
+// Hide elements not relevant to print media.
+////////////////////////////////////////////////////////////////////////////////
+@media print
+  // Hide icon container.
+  .content-icon-container
+    display: none !important
+
+  // Hide showing header links if hovering over when printing.
+  .headerlink
+    display: none !important
+
+  // Hide mobile header.
+  .mobile-header
+    display: none !important
+
+  // Hide navigation links.
+  .related-pages
+    display: none !important
+
+////////////////////////////////////////////////////////////////////////////////
+// Tweaks related to decolorization.
+////////////////////////////////////////////////////////////////////////////////
+@media print
+  // Apply a border around code which no longer have a color background.
+  .highlight
+    border: 0.1pt solid var(--color-foreground-border)
+
+////////////////////////////////////////////////////////////////////////////////
+// Avoid page break in some relevant cases.
+////////////////////////////////////////////////////////////////////////////////
+@media print
+  ul, ol, dl, a, table, pre, blockquote
+    page-break-inside: avoid
+
+  h1, h2, h3, h4, h5, h6, img, figure, caption
+    page-break-inside: avoid
+    page-break-after: avoid
+
+  ul, ol, dl
+    page-break-before: avoid

src/crate/theme/rtd/crate/static/vendor/furo/styles/base/_theme.sass

@@ -7,9 +7,9 @@ body
   @include fonts
   @include spacing
   @include icons
-  // @include admonitions
-  // @include default-admonition(#651fff, "abstract")
-  // @include default-topic(#14B8A6, "pencil")
+  @include admonitions
+  @include default-admonition(#651fff, "abstract")
+  @include default-topic(#14B8A6, "pencil")
 
   // @include colors
 

src/crate/theme/rtd/crate/static/vendor/furo/styles/base/_typography.sass

@@ -0,0 +1,105 @@
+// This file contains the styling for making the content throughout the page,
+// including fonts, paragraphs, headings and spacing among these elements.
+
+body
+  font-family: var(--font-stack)
+pre,
+code,
+kbd,
+samp
+  font-family: var(--font-stack--monospace)
+
+// Make fonts look slightly nicer.
+body
+  -webkit-font-smoothing: antialiased
+  -moz-osx-font-smoothing: grayscale
+
+// Line height from Bootstrap 4.1
+article
+  line-height: 1.5
+
+//
+// Headings
+//
+h1,
+h2,
+h3,
+h4,
+h5,
+h6
+  line-height: 1.25
+  font-family: var(--font-stack--headings)
+  font-weight: bold
+
+  border-radius: 0.5rem
+  margin-top: 0.5rem
+  margin-bottom: 0.5rem
+  margin-left: -0.5rem
+  margin-right: -0.5rem
+  padding-left: 0.5rem
+  padding-right: 0.5rem
+
+  + p
+    margin-top: 0
+
+h1
+  font-size: 2.5em
+  margin-top: 1.75rem
+  margin-bottom: 1rem
+h2
+  font-size: 2em
+  margin-top: 1.75rem
+h3
+  font-size: 1.5em
+h4
+  font-size: 1.25em
+h5
+  font-size: 1.125em
+h6
+  font-size: 1em
+
+small
+  opacity: 75%
+  font-size: 80%
+
+// Paragraph
+p
+  margin-top: 0.5rem
+  margin-bottom: 0.75rem
+
+// Horizontal rules
+hr.docutils
+  height: 1px
+  padding: 0
+  margin: 2rem 0
+  background-color: var(--color-background-border)
+  border: 0
+
+.centered
+  text-align: center
+
+// Links
+a
+  text-decoration: underline
+
+  color: var(--color-link)
+  text-decoration-color: var(--color-link-underline)
+
+  &:visited
+    color: var(--color-link--visited)
+    text-decoration-color: var(--color-link-underline--visited)
+    &:hover
+      color: var(--color-link--visited--hover)
+      text-decoration-color: var(--color-link-underline--visited--hover)
+
+  &:hover
+    color: var(--color-link--hover)
+    text-decoration-color: var(--color-link-underline--hover)
+  &.muted-link
+    color: inherit
+    &:hover
+      color: var(--color-link--hover)
+      text-decoration-color: var(--color-link-underline--hover)
+      &:visited
+        color: var(--color-link--visited--hover)
+        text-decoration-color: var(--color-link-underline--visited--hover)

src/crate/theme/rtd/crate/static/vendor/furo/styles/content/_admonitions.sass

@@ -0,0 +1,77 @@
+//
+// The design here is strongly inspired by mkdocs-material.
+.admonition, .topic
+  margin: 1rem auto
+  padding: 0 0.5rem 0.5rem 0.5rem
+
+  background: var(--color-admonition-background)
+
+  border-radius: 0.2rem
+  box-shadow: 0 0.2rem 0.5rem rgba(0, 0, 0, 0.05), 0 0 0.0625rem rgba(0, 0, 0, 0.1)
+
+  font-size: var(--admonition-font-size)
+
+  overflow: hidden
+  page-break-inside: avoid
+
+  // First element should have no margin, since the title has it.
+  > :nth-child(2)
+    margin-top: 0
+
+  // Last item should have no margin, since we'll control that w/ padding
+  > :last-child
+    margin-bottom: 0
+
+.admonition p.admonition-title,
+p.topic-title
+  position: relative
+  margin: 0 -0.5rem 0.5rem
+  padding-left: 2rem
+  padding-right: .5rem
+  padding-top: .4rem
+  padding-bottom: .4rem
+
+  font-weight: 500
+  font-size: var(--admonition-title-font-size)
+  line-height: 1.3
+
+    // Our fancy icon
+  &::before
+    content: ""
+    position: absolute
+    left: 0.5rem
+    width: 1rem
+    height: 1rem
+
+// Default styles
+p.admonition-title
+  background-color: var(--color-admonition-title-background)
+  &::before
+    background-color: var(--color-admonition-title)
+    mask-image: var(--icon-admonition-default)
+    mask-repeat: no-repeat
+
+p.topic-title
+  background-color: var(--color-topic-title-background)
+  &::before
+    background-color: var(--color-topic-title)
+    mask-image: var(--icon-topic-default)
+    mask-repeat: no-repeat
+
+//
+// Variants
+//
+.admonition
+  border-left: 0.2rem solid var(--color-admonition-title)
+
+  @each $type, $value in $admonitions
+    &.#{$type}
+      border-left-color: var(--color-admonition-title--#{$type})
+      > .admonition-title
+        background-color: var(--color-admonition-title-background--#{$type})
+        &::before
+          background-color: var(--color-admonition-title--#{$type})
+          mask-image: var(--icon-#{nth($value, 2)})
+
+.admonition-todo > .admonition-title
+  text-transform: uppercase

src/crate/theme/rtd/crate/static/vendor/furo/styles/content/_api.sass

@@ -0,0 +1,121 @@
+// This file stylizes the API documentation (stuff generated by autodoc). It's
+// deeply nested due to how autodoc structures the HTML without enough classes
+// to select the relevant items.
+
+// API docs!
+dl[class]:not(.option-list):not(.field-list):not(.footnote):not(.glossary):not(.simple)
+  // Tweak the spacing of all the things!
+  dd
+    margin-left: 2rem
+    > :first-child
+      margin-top: 0.125rem
+    > :last-child
+      margin-bottom: 0.75rem
+
+  // This is used for the arguments
+  .field-list
+    margin-bottom: 0.75rem
+
+    // "Headings" (like "Parameters" and "Return")
+    > dt
+      text-transform: uppercase
+      font-size: var(--font-size--small)
+
+    dd:empty
+      margin-bottom: 0.5rem
+    dd > ul
+      margin-left: -1.2rem
+      > li
+        > p:nth-child(2)
+          margin-top: 0
+        // When the last-empty-paragraph follows a paragraph, it doesn't need
+        // to augument the existing spacing.
+        > p + p:last-child:empty
+          margin-top: 0
+          margin-bottom: 0
+
+  // Colorize the elements
+  > dt
+    color: var(--color-api-overall)
+
+.sig:not(.sig-inline)
+  font-weight: bold
+
+  font-size: var(--api-font-size)
+  font-family: var(--font-stack--monospace)
+
+  margin-left: -0.25rem
+  margin-right: -0.25rem
+  padding-top: 0.25rem
+  padding-bottom: 0.25rem
+  padding-right: 0.5rem
+
+  // These are intentionally em, to properly match the font size.
+  padding-left: 3em
+  text-indent: -2.5em
+
+  border-radius: 0.25rem
+
+  background: var(--color-api-background)
+  transition: background 100ms ease-out
+
+  &:hover
+    background: var(--color-api-background-hover)
+
+  // adjust the size of the [source] link on the right.
+  a.reference
+    .viewcode-link
+      font-weight: normal
+      width: 4.25rem
+
+em.property
+  font-style: normal
+  &:first-child
+    color: var(--color-api-keyword)
+.sig-name
+  color: var(--color-api-name)
+.sig-prename
+  font-weight: normal
+  color: var(--color-api-pre-name)
+.sig-paren
+  color: var(--color-api-paren)
+.sig-param
+  font-style: normal
+
+div.versionadded,
+div.versionchanged,
+div.deprecated,
+div.versionremoved
+  border-left: 0.1875rem solid
+  border-radius: 0.125rem
+
+  padding-left: 0.75rem
+
+  p
+    margin-top: 0.125rem
+    margin-bottom: 0.125rem
+
+div.versionadded
+  border-color: var(--color-api-added-border)
+  .versionmodified
+    color: var(--color-api-added)
+
+div.versionchanged
+  border-color: var(--color-api-changed-border)
+  .versionmodified
+    color: var(--color-api-changed)
+
+div.deprecated
+  border-color: var(--color-api-deprecated-border)
+  .versionmodified
+    color: var(--color-api-deprecated)
+
+div.versionremoved
+  border-color: var(--color-api-removed-border)
+  .versionmodified
+    color: var(--color-api-removed)
+
+// Align the [docs] and [source] to the right.
+.viewcode-link, .viewcode-back
+  float: right
+  text-align: right

src/crate/theme/rtd/crate/static/vendor/furo/styles/content/_blocks.sass

@@ -0,0 +1,7 @@
+.line-block
+  margin-top: 0.5rem
+  margin-bottom: 0.75rem
+  .line-block
+    margin-top: 0rem
+    margin-bottom: 0rem
+    padding-left: 1rem

src/crate/theme/rtd/crate/static/vendor/furo/styles/content/_captions.sass

@@ -0,0 +1,19 @@
+// Captions
+article p.caption,
+table > caption,
+.code-block-caption
+  font-size: var(--font-size--small)
+  text-align: center
+
+// Caption above a TOCTree
+.toctree-wrapper.compound
+  .caption, :not(.caption) > .caption-text
+    font-size: var(--font-size--small)
+    text-transform: uppercase
+
+    text-align: initial
+    margin-bottom: 0
+
+  > ul
+    margin-top: 0
+    margin-bottom: 0