chore(demo): add yfm editor brand

Author: d3m1d0v

.storybook/manager.ts

@@ -0,0 +1,6 @@
+import {addons} from '@storybook/addons';
+import {themes} from './theme';
+
+addons.setConfig({
+    theme: themes.light,
+});

.storybook/theme.ts

@@ -0,0 +1,41 @@
+import {create} from '@storybook/theming';
+
+export const ThemeLight = create({
+    base: 'light',
+
+    colorPrimary: '#027bf3',
+    colorSecondary: 'rgba(2, 123, 243, 0.6)',
+
+    // Typography
+    fontBase: '"Helvetica Neue", Arial, Helvetica, sans-serif',
+    fontCode:
+        '"SF Mono", "Menlo", "Monaco", "Consolas", "Ubuntu Mono", "Liberation Mono", "DejaVu Sans Mono", "Courier New", "Courier", monospace',
+
+    // Text colors
+    textColor: 'black',
+    textInverseColor: 'black',
+
+    // Toolbar default and active colors
+    barTextColor: 'silver',
+    barSelectedColor: '#027bf3',
+    // barBg: '#027bf3',
+
+    // Form colors
+    inputBg: 'white',
+    inputBorder: 'silver',
+    inputTextColor: 'black',
+    inputBorderRadius: 4,
+
+    brandUrl: 'https://github.com/yandex-cloud/yfm-editor',
+    brandTitle: `<div style="font-size: 18px; color: #027bf3; font-weight: 600; margin-top: -6px; margin-bottom: 2px;">YFM Editor</div>
+                <div style="font-size: 14px;color: #7d7d7d;font-weight: 400;">Wysiwyg editor</div>`,
+});
+
+export const ThemeDark = create({
+    base: 'dark',
+});
+
+export const themes = {
+    light: ThemeLight,
+    dark: ThemeDark,
+};