Presentations: Themes & Styling
Control the visual identity of your deck with built-in themes, a custom theme builder, brand extraction, and font management.
Built-in Themes
OpenCharts ships with 20+ professionally designed themes. Each theme defines six colors (primary, accent, background, surface, text, muted text), heading and body fonts, and a light/dark mode. Click a theme card in the Theme panel to apply it instantly.
Custom Theme Builder
Create a theme that matches your brand. Open the Theme panel → Create Custom Theme.
Colors
Configure six color roles: Primary, Accent, Background, Surface, Text, and Muted Text. Each has a color picker with hex input and preset swatches.
Fonts
Choose heading and body fonts from a 1,500+ font catalog. The picker shows a live preview of each font, with search and category filtering (serif, sans-serif, display, handwriting, monospace).
Logo
Upload a logo (PNG, JPG, SVG, WEBP, max 2 MB). Choose placement: top-left, top-center, top-right, bottom-left, bottom-center, or bottom-right. The logo appears on all slides.
Light / Dark Mode
Toggle light or dark mode for the theme. This controls the default background brightness.
Brand Extraction from URL
Enter a company website URL and OpenCharts will extract brand colors, fonts, and logo automatically with Theo Brand Kit. The URL is checked against Theo's safety screen before fetching.
Extracted values are pre-filled into the custom theme builder so you can tweak before saving.
Extract Theme from Imported File
When you import a PowerPoint or PDF in the presentation wizard, OpenCharts automatically detects the visual theme of the source file — colors, fonts, and light/dark mode.
A "Theme detected from your file" banner appears in the Theme step with a preview of the extracted colors. You can:
- Use This Theme — apply the extracted theme directly to your presentation.
- Customize — open the Custom Theme Builder pre-filled with the extracted values so you can adjust colors, fonts, and add a logo before saving.
For PPTX files, extraction is instant and deterministic (read directly from the file's embedded theme). For PDFs, the AI analyzes the first few pages to detect the dominant color palette and fonts.
Theme Categories
Custom themes are organized into categories for easy browsing:
Corporate
Creative
Minimal
Bold
AI-Assisted Theming
The AI wizard can suggest a theme based on your presentation topic. During the wizard flow, describe the look you want (e.g. "modern tech startup, dark mode, blue accents") and the AI selects or generates matching colors and fonts.
You can also describe a visual style in the AI sidebar to restyle all slides at once.
Theme Tips
• Test your theme on a slide with all element types (text, image, chart, code) to ensure everything is readable.
• Use the muted text color for captions and footnotes to create visual hierarchy.
• For printed handouts, prefer light backgrounds with high-contrast text.
• Custom themes are saved to your account and available across all presentations.
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Presentations: Publishing & Export
Publish to the web with custom domains, export to PDF/PPTX/PNG, and convert from flowcharts or notes.