Add semantic color tokens to BaseStyles (#1880)

* Add new semantic color tokens to BaseStyles

* Remove unnecessary aliases

* Fix border typo

* Fix comments

* Rename color role normal to neutral

* Update special color names

* Add disabled colors

* Remove aliasing logic

All colors are now named directly as their aliases. The 4-part token structure only serves as a mental model but is omitted in code (it will be detailed in documentation). This makes things more consistent, reduces the number of variables in global styles, and aligns closely to Figma.

* Update snapshots

* Document custom properties on theme page

* Add changeset

* Add ref to Figma in docs and fix typos

.changeset/itchy-buttons-tan.md

@@ -0,0 +1,5 @@
+---
+'@sumup/circuit-ui': minor
+---
+
+Added semantic color tokens as CSS custom properties to the `BaseStyles`. See the [documentation](https://circuit.sumup.com/?path=/docs/features-theme--page) for details.

.storybook/components/ColorsTable.tsx

@@ -0,0 +1,108 @@
+/**
+ * Copyright 2023, SumUp Ltd.
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { useEffect, useState } from 'react';
+import { css, ThemeProvider } from '@emotion/react';
+import { light } from '@sumup/design-tokens';
+import {
+  Anchor,
+  spacing,
+  Table,
+  ToastProvider,
+  useNotificationToast,
+} from '@sumup/circuit-ui';
+
+const getCustomProperty = (property: string) => {
+  return getComputedStyle(document.documentElement).getPropertyValue(property);
+};
+
+function Copy({ property }: { property: string }) {
+  const { setToast } = useNotificationToast();
+  return (
+    <Anchor
+      css={spacing({ left: 'kilo' })}
+      size="two"
+      /* https://caniuse.com/mdn-api_clipboard_writetext */
+      onClick={() =>
+        navigator.clipboard
+          .writeText(property)
+          .then(() => setToast({ body: 'Copied!', variant: 'confirm' }))
+      }
+    >
+      Copy
+    </Anchor>
+  );
+}
+
+const getRows = (customProperties: string[][]) => {
+  return customProperties.map(([property, value]) => [
+    {
+      children: (
+        <div
+          css={css`
+            display: flex;
+          `}
+        >
+          <code>{property}</code>
+          <Copy property={property} />
+        </div>
+      ),
+    },
+    { children: <code>{value}</code> },
+    {
+      align: 'right' as const,
+      children: (
+        <span
+          css={css`
+            display: block;
+            width: auto;
+            height: 1em;
+            background: var(${property});
+            border: 1px solid var(--cui-border-normal);
+          `}
+        />
+      ),
+    },
+  ]);
+};
+
+function ColorsTable({ customProperties }: { customProperties: string[] }) {
+  const [colors, setColors] = useState<string[][]>();
+
+  useEffect(() => {
+    setColors(
+      customProperties.map((property) => [
+        property,
+        getCustomProperty(property),
+      ]),
+    );
+  }, []);
+
+  return (
+    <ThemeProvider theme={light}>
+      <ToastProvider>
+        {colors && (
+          <Table
+            condensed
+            headers={['Property name', 'Color value', 'Preview']}
+            rows={getRows(colors)}
+          />
+        )}
+      </ToastProvider>
+    </ThemeProvider>
+  );
+}
+
+export default ColorsTable;

.storybook/components/index.js

@@ -28,6 +28,7 @@ export { default as Swatch } from './Swatch';
 export { default as Type } from './Type';
 export { default as Spacing } from './Spacing';
 export { default as MediaQueriesTable } from './MediaQueriesTable';
+export { default as ColorsTable } from './ColorsTable';
 export { default as BorderWidth } from './BorderWidth';
 export { default as BorderRadius } from './BorderRadius';
 export { default as IconSize } from './IconSize';

.storybook/util/theme.js

@@ -70,7 +70,7 @@ export const components = {
   h4: withThemeProvider(Headline, {
     as: 'h4',
     size: 'four',
-    css: spacing({ top: 'giga' }),
+    css: spacing({ top: 'giga', bottom: 'mega' }),
   }),
   h5: withThemeProvider(SubHeadline, {
     as: 'h5',